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    Posts made by moaaz

    • Cyberian Mobile Application Launched!

      We are happy to announced that Android application has been launched. You can download as following link.
      Download Link Available.

      posted in Announcements
      M
      moaaz
    • RE: How to Copy Quiz and Paste or direct Google Search - VU Quiz

      Chrome extension link activate now you can download from below link

      VU Quiz Extension

      posted in Virtual University
      M
      moaaz
    • RE: CS311 Quiz 2 Solution and Discussion

      XML Quiz
      For each question, choose the best choice out of the given choices.

      1. What does XML stand for?
        A. X-Markup Language
        B. eXtra Modern Link
        C. Example Markup Language
        D. eXtensible Markup Language

      2. XML’s goal is to replace HTML
        A. True
        B. False

      3. What does DTD stand for?
        A. Direct Type Definition
        B. Document Type Definition
        C. Document Type Declaration

      4. Is this a correct XML document?
        <?xml version=”1.0”?>
        <to>Students</to>
        <from>Teacher</from>
        <heading>Reminder</heading>
        <body>We are at Software Park, Thailand</body>
        A. Yes
        B. No

      5. Which statement is true?
        A. All XML elements must have a closing tag
        B. All XML documents must have a DTD or an XML schema
        C. All XML elements must be lowercase
        D. All of the statements are true

      6. Which statement is true?
        A. XML tags are case sensitive
        B. XML elements must be properly nested
        C. XML documents must have the root element
        D. All the statements are true

      7. XML preserves white spaces
        A. True
        B. False

      8. Is this a correct XML document?
        <?xml version=”1.0”?>
        <note>
        <to age=19>Students</to>
        <from>Teacher</from>
        </note>

      A. No
      B. Yes

      1. XML elements cannot be empty
        A. True
        B. False

      2. Which is not a correct name for an XML element?
        A. <Note>
        B. <h1>
        C. <1dollar>
        D. All 3 names are incorrect

      3. Which is not a correct name for an XML element?
        A. <age>
        B. <first name>
        C. <NAME>
        D. All 3 names are incorrect

      4. Which is not a correct name for an XML element?
        A. <xmldocument>
        B. <document>
        C. <doc>

      5. For the XML parser to ignore a certain section of your XML document, which syntax is correct?
        A. <xml:CDATA[ Text to be ignored]>
        B. <CDATA>Text to be ignored</CDATA>
        C. <![CDATA[ Text to be ignored ]]>

      6. XML is a subset of SGML
        A. True
        B. False

      7. XML attributes must be in double quotes
        A. True
        B. False

      8. XML attributes must be assigned values
        A. True
        B. False

      9. The Document Type Definition must be stored in an external file
        A. True
        B. False

      10. What can XML do?
        A. The standard for automating data exchange between systems
        B. The standard for displaying data on the Web
        C. The standard for a cross-platform programming language

      11. Which is false?
        A. XML is used to describe only structured data
        B. XML is used to only on the Internet
        C. XML is used to represent only simple data
        D. All of the above

      12. Which of the following comments are not well formed?
        A. <!-- define <source> -->
        B. <!-- define <source> -->
        C. <!-- declaration — 10.27.2004 -->
        D. <!— this is a valid comment -->

      13. Provided that the file x.dtd has the following contents. Which of the xml files are valid?
        <!ELEMENT test (a, b)>
        <!ELEMENT a ANY>
        <!ELEMENT b (#PCDATA | c)*>
        <!ELEMENT c EMPTY>
        <!ATTLIST c valid (true | false) #IMPLIED>

      a. <?xml version=”1.0” encoding=”ISO-8859-1”?>
      <!DOCTYPE test SYSTEM “x.dtd”>
      <test>
      <a/>
      <b>text<c valid=”true”/></b>
      </test>

      b. <?xml version=”1.0” encoding=”ISO-8859-1”?>
      <!DOCTYPE test SYSTEM “x.dtd”>
      <test>
      <a>Element <a>can</a>
      contain <anything/></a>
      </test>

      c. <?xml version=”1.0” encoding=”ISO-8859-1”?>
      <!DOCTYPE a SYSTEM “x.dtd”>
      <b>Sample</b>

      1. How can you declare in a DTD that the element x contains either the element a or the element b, but not both of them
        a) <!ELEMENT x a|b>
        b) <!ELEMENT x (a|b)>
        c) <!ELEMENT x (a?, b?)>
        d) It is not possible to declare in a DTD that one element contains either the element a or the element b, but not both of them

      2. How can you declare in a DTD that the element x contains the element a, or the element b, or both of them in the sequence a b.
        a) <!ELEMENT x a|b>
        b) <!ELEMENT x (a|b)>
        c) <!ELEMENT x (a?, b?)>
        d) None of the declarations above does solve the problem.

      3. How can you declare in a DTD that the empty element x has either the attribute a or the attribute b (or both of them). The attributes contain any value.
        a) <!ELEMENT x EMTPY>
        <!ATTLIST (a|b) CDATA #REQUIRED>

      b) <!ELEMENT x EMPTY>
      <!ATTLIST a CDATA #REQUIRED>
      <!ATTLIST b CDATA #REQUIRED>

      c) <!ELEMENT x EMPTY>
      <!ATTLIST a CDATA #REQUIRED
      b CDATA #REQUIRED>

      d) It is not possible to make the presence of one attribute depend on another attribute

      1. How can you in a DTD declare that the element x contains both attributes a and b and that the order of them has to be ab? The attributes can contain any value
        a) <!ELEMENT x EMPTY>
        <!ATTLIST (a,b) CDATA #REQUIRED>

      b) <!ELEMENT x EMPTY>
      <!ATTLIST a CDATA #REQUIRED>
      <!ATTLIST b CDATA #REQUIRED>

      c) <!ELEMENT x EMPTY>
      <!ATTLIST a CDATA #REQUIRED>
      b CDATA #REQUIRED>

      d) It is not possible to specify the order of attributes in a DTD. The order of attributes does not matter in XML.

      e) It is not possible to specify the order of attributes in a DTD. The order of attributes can be specified only in an XML schema.

      Valid names of elements and attributes start with a letter, an underscore or a colon, the following allowed characters are letters, numeric characters, colon, underscore, dot and hyphen (minus). Names which start with “xml” (in any case) are reserverd for W3C. The colon has a special meaning with namespaces and should not be used with any other semantic.

      posted in CS311 - Introduction to Web Services Development
      M
      moaaz
    • RE: CS311 Quiz 2 Solution and Discussion
      1. Which method does SAX use for processing XML documents?

      a) Event Based
      b) DocumentHandler
      c) Document
      d) Tree based

      Answer : a

      1. Which method does DOM use for processing XML documents?

      a) Event Based
      b) DocumentHandler
      c) Document
      d) Tree based

      Answer : d

      1. Which interfaces are part of the SAX2 API?

      a) ContentHandler, ErrorHandler, DTDHandler, EntityResolver
      b) DocumentHandler, ErrorHandler, DTDHandler, EntityHandler
      c) DocumentHandler, Errorhandler, DTDHandler, SchemaHandler
      d) DocumentHandler, Errorhandler, DTDHandler, EntityResolver

      Answer : a

      1. Which is the best description of the “characters()” method?

      a) a method of DOM API to insert character data in the XML document
      b) a method of the SAX ContentHandler interface to receive notification
      of the presence of character data
      c) a method of the DOM interface to replace the entity reference
      with the character data
      d) None of these.

      Answer : b

      1. An XML document to be processed is very large. The application extracts a small portion of the information from the document. Memory and speed may be constraints. Which method or methods are most appropriate for this situation?

      a) Use SAX
      b) Use DOM
      c) Extract the necessary information and process using XSLT.
      d) Use a schema-based approach.

      Answers : a

      1. When you construct an XML using a DOM enabled Parser, the same parser should be used to process back
        the XML document when the process involves legacy applications, otherwise it is not necessary to do so.

      a) Not really
      b) Yes, whenver the process is between legacy conectivity this is better.
      c) You can use SAX enabled parser to fill this gap.
      d) This statement is not a correct one, because DOM is constructed using IDL.

      Answer : d

      1. When Processing Instructions are a part of your parsing process, DOM should be used,
        since SAX cannot be used to detect a Processing Instruction in a document.

      a)true
      b)false

      Answer : a

      1. Consider a system which is memory & speed constraint. The application is to process XML documents,
        sort the contents and mail them to a higher configuration machine for transformation. Which is the best approach?

      a) Use platform native language to process the docuements
      b) Use DOM based approach.
      c) Using SAX based approach is the best.
      d) DOM and SAX must be used in this context.

      Answer : b

      1. When receiving documents from a non-trusted agent, the best way to process the documents is:

      a) Use SAX
      b) Use DOM
      c) Both can be used here.
      d) Both can be used but validity is an issue here.

      Answer: d

      1. In DOM, the Document interface is the only interface that allows you to create other DOM document components.

      a)true
      b)false

      Answer: a

      1. XSLT is essentially a tool for translating what kind of documents?

      a) XML
      b) PDF
      c) DOM
      d) RTF

      Answers: a

      1. Use of SAX based parser is most likely to be used in which of the following scenarios?

      a) You want to process the document in a sequential order only.
      b) The documents is very large.
      c) When there is no need to validate XML documents.
      d) The parser implements only SAX based approach.

      Answers: a, b

      1. DOM can be used to process HTML documents.

      a)true
      b)false

      Answer: a

      1. What error types does the SAX2 ErrorHandler interface handle?

      a) informational, warning, fatal-error
      b) warning, error, fatal-error
      c) warning, error
      d) informational, warning, error, fatal-error

      Answer: b

      1. A DOM-based parser should be used for which of the following situations?

      a) Need to modify the XML document directly
      b) Performance and/or memory is an issue
      c) Need to have random access to the components of the XML document
      d) Only need to process the XML document sequentially

      Answer: a, c

      posted in CS311 - Introduction to Web Services Development
      M
      moaaz
    • RE: BIO202 Gdb1 Solution and discussion

      In the two families of nucleic acids, ribonucleic acid (RNA) and deoxyribonucleic acid (DNA), the sequence of nucleotides in the DNA or RNA codes for the structure of proteins synthesized in the cell. The nucleotide adenosine triphosphate (ATP) supplies the driving force of many metabolic processes. Several nucleotides are coenzymes; they act with enzymes to speed up (catalyze) biochemical reactions.

      The nitrogen-containing bases of nearly all nucleotides are derivatives of three heterocyclic compounds: pyrimidine, purine, and pyridine. The most common nitrogen bases are the pyrimidines (cytosine, thymine, and uracil), the purines (adenine and guanine), and the pyridine nicotinamide.

      The nucleotides are of great importance to living organisms, as they are the building blocks of nucleic acids, the substances that control all hereditary characteristics.

      posted in BIO202 – BIOCHEMISTRY-1
      M
      moaaz
    • RE: ECO603 GDB.1 Solution and Discussion

      There is an urgent need for policy makers to adopt a cautious perspective when dealing with the recent revival of protectionism. The changing policy context of global competition requires that emphasis be placed on facilitating broad-based innovation. This is in sharp contrast to the current and past industrial policies that were based on import substitution and sector-picking. This paper briefly outlines Pakistan’s experience with industrial policy over the past 6 decades, and shows how protectionist industrial and trade policy regimes are ineffective with respect to equipping Pakistan to compete globally. The paper also outlines global best practices with reference to designing an enabling industrial policy and suggests policy reforms that are appropriate in the political and global context of Pakistan. There also exist contrary views about the scope and composition of industrial policy even within the government functionaries. There is a dire need for a shared vision and deeper consensus building. Thus this paper aims to highlight the radical contrast in perspectives that exists between the current policy of the ministry of industries and a policy conducive to a prosperous Pakistan.

      Source

      posted in ECO603 - International Economics
      M
      moaaz
    • RE: FIN704 GDB2 Solution and discussion

      Accounts Receivable Management
      How to prepare a good Accounts Receivable policy

      Accounts receivable management incorporates is all about ensuring that customers pay their invoices. Good receivables management helps prevent overdue payment or non-payment. It is therefore a quick and effective way to strengthen the company’s financial or liquidity position. This Wiki explains the importance of receivables management, the benefits and how to prepare a good receivables process.

      The importance of receivables management
      What is the benefit?
      Preparing good receivables management
      Which systems will you require?
      Automating receivables management
      

      The importance of receivables management

      Every company wants to buy low and sell high. But they can lose everything with poor receivables management during the last phase of the sales process (payment). Over half of all bankruptcies can be attributed to poor receivables management, which demonstrates its importance. Receivables management involves much more than reminding customers to pay. It is also about identifying the reason for non-payment. Perhaps a product or service was not delivered? Or there was an administrative error in the invoice? Good receivables management is a comprehensive process consisting of:

      Determining the customer’s credit rating in advance
      Frequently scanning and monitoring customers for credit risks
      Maintaining customer relations
      Detecting late payments in due time
      Detecting complaints in due time
      Reducing the total balance outstanding (DSO)
      Preventing any bad debt in receivables outstanding
      

      What is the benefit?

      Good receivables management directly contributes to a company’s profit because it reduces bad debt. The company also has a better cash flow and higher available liquidity for use in investments or acquisitions. Furthermore, good receivables management boosts a company’s professional image.
      Preparing good receivables management

      In principle, good receivables management involves two steps. Firstly, you determine your strategy and then you specify the appropriate procedures.
      Step 1. Determine the strategy

      Which customers do you accept and under which conditions?
      Which customers do you monitor?
      Who should no longer be accepted, and when is the exit?
      

      Step 2. Prepare appropriate procedures

      What is your invoicing process like?
      What is your invoice like?
      When do you remind a customer by phone?
      When do you remind a customer in writing?
      What does the reminder look like?
      When do you engage a debt collection agency?
      When will you start legal proceedings?
      What is the role of your employees in this respect? Will you choose outsourcing or in-house management?
      

      Which systems will you require?

      Companies use different applications and systems to limit the risks and update the data. These can help you set up and design your receivables management.

      Acceptance system. Based on credit information, you determine whether a new customer is accepted or not. This may be a manual or automated process.
      Monitoring system. This system checks the entire portfolio for continuous insight into existing customers and suppliers. This is essential, particularly with regard to chain parties.
      Invoicing system. Invoices may be sent manually or automated (sometimes as a digital invoice) and reminders must be logically aligned.
      Bookkeeping system. All receivables and payables are booked in this system, which provides insight into the cash flow and receivables risk.
      CRM system. The Customer Relationship Management (CRM) system lists information relating to agreements, contact and contracts with customers. Complaints can also be processed in this system to improve insight into the background of non-payment. 
      

      Automating receivables management

      Automating receivables management allows you to link all the above systems. This improves workflow efficiency and provides better insight by generating cash flow and customer reports. Automatically linking credit information reduces the percentage of non-paying new customers. By automatically integrating the debt collections in the process, the percentage of non-paying existing customers also falls.

      Source

      posted in FIN704 - Managerial Accounting
      M
      moaaz
    • RE: ZOO506 GDB1 Solution and discussion

      Diseases and parasites play a major role in most ecosystem dynamics; yet, they have received relatively little attention in ecological modelling [1–3]. Traditionally, ecologists have mostly considered disease outbreaks as disturbances rather than as an integral part of the ecosystem dynamics [4]. However, there is mounting evidence that diseases and parasites play a vital role in the stability and dynamics of most ecosystems [5–9].

      In this paper we will consider the effects of a disease that specifically infects juvenile individuals and subsequently prevents the infected individual from producing offspring. The work is inspired by the interaction between the tape worm Ligula intestinalis and its cyprinid fish host species roach (Rutilis rutilis). The parasite has a complex life cycle, involving three host species. The final host species of the parasite are fish eating birds, such as cormorant (Phalacrocorax carbo), grey herron (Ardea cinerea), and great crested grebe (Podiceps cristatus) [10]. In this final host the parasite completes its sexual cycle and produces eggs, which are shed to the water via the faeces of the birds. The larvae of the parasite are eaten by copepods, which in turn are a primary food source for the juvenile fish. After a fish is infected, the parasite settles and grows in the host gut system and may obtain a staggering weight of up to half the host weight [11]. Surprisingly, the physical condition of such a fish-parasite combination can be not noticeably different from uninfected individuals [12]. However, the consequences for the infected fish are severe, as the parasites supress gonad development and consequently prevent the individual from maturing. Even infection with a single parasite can act to sterilize the infected fish [12]. Furthermore, the parasite might induce behavioural changes, such as directing the infected fish to move to the littoral zone, where it can be caught more easily by the fish eating birds and thus complete the parasite life cycle [13,14].

      Also the consequences of the parasite infection on the host population dynamics can be extensive. A well-documented case are the recurrent Ligula parasite outbreaks in the roach population of lake Slapton Ley [11,15,16]. The roach population in this lake shows a tendency to build-up a so-called stunted population. In this population state, small juvenile individuals are very numerous. This causes exploitation competition amongst juveniles to be so fierce, that individual growth rate substantially slows down, effectively preventing juveniles from reaching the size necessary for maturation [16,17].

      In this stunted population situation, the Ligula parasite can cause a large epidemic, reaching a prevalence of more than 70% of all juveniles being infected [11]. This in turn seems to act to relieve the stuntedness in the juvenile population, causing a reduction in the juvenile population size, with a subsequent acceleration in juvenile growth and maturation, accompanied by a strong reduction of the parasite prevalence. However, hereafter, the stuntedness in the host population slowly rebuilds, after which a second epidemic of the parasite can occur. In the case of the Slapton Ley dataset, such recurrent epidemics were recorded three times, spanning a total period of 31 years [11].

      In this paper we will study a mathematical model to investigate the interplay between ecological population dynamics of a potentially stunted population and a disease. Furthermore, we will study the interaction between the disease and a natural predator of the host. In the Ligula–Roach system there are several predators on Roach, including Northern Pike (Esox Lucius) and European Perch (Perca fluvitilis). Often, such predator species are of commercial or recreational interest for fisherman, and stunting of the prey species can greatly affect predator numbers or predator quality. Here, we will study the potential indirect influence of a prey disease on the predator species. For the ecological baseline, we will use a model that we have introduced before for the dynamics of a structured prey population and a predator that attacks adult prey [18,19]. In this model a stunted juvenile prey population can build up due to a maturation bottleneck, and it has a parameter region of bistability between a stunted and non-stunted equilibrium state [19]. To this system we will add a disease that specifically infects juvenile individuals, and that acts to sterilize these individuals and prevents maturation. In this way we can study the indirect interaction between a predator and a disease, that both attack the same host species, but each targeting a different host life stage. For mathematical simplicity, we model a disease that spreads through direct contact. This differs from the parasite infection in the Ligula-Roach system, where the parasite has to pass through two additional host stages. Our simplified model would roughly correspond to a constancy assumption in the copepod and bird populations. Furthermore, we do not explicitly account for individual parasite load, but instead we only distinguish between infected and uninfected individuals.

      Our main objective in this paper is to study the effects of a disease that infects and sterilizes juvenile individuals on the population dynamics of its host species. In particular, we will focus on a system where the host population is in a stunted population state, which is strongly dominated by juvenile individuals and where individual growth rate and maturation are strongly reduced. We will map the dynamic consequences of introducing such a disease in a stunted host population state. It will turn out that these consequences strongly depend on the ability of infected juveniles to compete with uninfected conspecifics. We will discuss the biological implications of our results.

      Source

      posted in ZOO506 - Applied Entomology and Pest Management
      M
      moaaz
    • RE: ZOO506 GDB1 Solution and discussion

      Parasite: Living place of one organism into another organism called host. Parasite depend on its host for persist. It cannot live without host because it almost never kill the host but it can spread disease. Their size is smaller than their host but their reproduction rate is faster than the host. Different parasites can effect humans in different ways and cause disease like malaria. Parasite work the host’s staff to fuel its life cycle.
      Two types of parasites:
      Endow parasite:
      The parasite live inside the parasite for example tapeworm, flatworm etc.the parasite also depend on third organism called vector.
      Ectoparasite:
      The parasite that lives outside the body called ectoparasite.
      Predator:
      The interaction between two organisms called predation. One is predator and other is prey. Flow of energy from one to another.
      Types of predation:
      1 Carnivory
      2 Herbivory
      3 Mutualism
      . Parasitism
      4 carnivory
      carnivorous predarors kill and eat their prey. it involve the large animals like lion or tiger.
      Parasitism:
      It is the form of predation where the host provides necessary nutrients for the survival and reproduction of parasite.
      Herbivory
      herbivores using up the autographs such as plants and photosynthetic like algae.
      Mutualism:
      Interaction between two organisms in which host supply the nutrition for another speices.in this case the host not harmed.

      posted in ZOO506 - Applied Entomology and Pest Management
      M
      moaaz
    • CS706 Assignment 4 Solution and Discussion

      Video Presentation of Academic Research Paper
      For the presentation activity, students are required to record their video while presenting academic research paper slides, then put recorded video and slides in a zip file and upload it on VU-LMS. Therefore, each student is required to prepare PPTs of his/her academic research paper and then record his/her video while presenting the slides. Following are the guidelines in this regard:
      PPT Slides:

      1. Prepare presentation slides related to your academic research paper.
      2. There must not be more than 20 slides in your PPT file.
      3. First slide should contain student-ID, student-name, topic and course-name.
      4. Your presentation should describe the problem statement, methodology and conclusion.
      5. Save your presentation slides in .ppt or .pptx format.
        Video Recording:
      6. You have to formally present the slides with proper dress code and have to record the video of your presentation.
      7. You can use any video recording facility such as web cam, camera, mobile phone etc. for recording of your presentation (Download link of the tutorial “Tips for Recording Videos” is provided in the assignment package).
      8. The total time for recording should not exceed 10 minutes.
      9. After recording your video, you have to convert it in “.3gp” format using any video conversion tool to reduce the size of the video file. (Download link of the tutorial “Video Compression” is provided in the assignment package).
      10. After converting the video in .3gp format, review your file to verify that audio and video are playing properly.
      11. Install VLC media player to view your compressed video before uploading on VU-LMS. You can download VLC from http://www.videolan.org/vlc/download-windows.html.
      12. It is preferable to use English in your presentation in case of reluctance you can also use Urdu language.
      13. Note that you will record your presentation standing in front of camera.
      14. Students writing academic paper in group should submit presentation individually with their own video recording.
        Submission:
      15. Compress your video file and presentation file using any compression tool like WinZip or WinRAR.
      16. Upload the compressed file (.zip or .rar) on VU-LMS. Make sure that its size should not exceed 30 MB.

      Note: It is not required to show PPT slides in the recorded video.

      Tips for Recording Videos:
      http://vulms.vu.edu.pk/Courses/CS701/Downloads/Tips for Recording Videos.mp4

      Video Compression:
      http://vulms.vu.edu.pk/Courses/CS701/Downloads/Video Compression.mp4

      posted in CS706 - Software Quality Assurance
      M
      moaaz
    • RE: CS609 GDB1 Solution and discussion

      @zaasmi said in CS609 GDB1 Solution and discussion:

      By increasing the surface area of hard disk there is an increase of data storage. Do you think whether there is any negative impact of increasing surface area as well?

      Yes, by increasing the surface area of hard disk there is an increase of data storage negative impact of increasing surface area as well As a greater amount of magnetic media can reside on the hard surface of the disk also because the surface area of the disk is increased by increasing the number of platters.
      Increasing the surface area clearly increases the amount of data that can reside on the disk as more magnetic media no resides on disk but it might have some drawbacks like increased seek time in case only one disk platter is being used.

      posted in CS609 - System Programming
      M
      moaaz
    • RE: BIO204 GDB1 Solution and discussion

      Freeze drying

      Freeze drying (lyophilization) is a dehydration process which allows water to sublimate directly from solid phase to vapour phase at and below the freezing temperature of the material. Sub-atmospheric pressure (< 40 Pa) is maintained in most freeze-drying operations and the condensed water is immediately removed (Pikal, 2007). Freeze drying has been for decades one of the most preferred preservation methods for culture collection maintenance (Morgan et al., 2006). Due to high viability losses, an initial bacterial load of greater than 107 viable cells/mL has been recommended to ensure sufficient cells survive the freeze-drying process, thereby giving better success in storage, reconstitution and propagation (Bozoglu et al., 1987).

      At commercial scale, operational and capital costs of freeze drying are very high. The freeze-drying process operates in batch mode and requires long drying times and large drying units to achieve mass production. Even so, freeze drying is currently the only drying method used at commercial scale for production of starter cultures intended for use as primary acid producers in dairy fermentations.

      It is reported that the majority of bacterial death occurring during freeze drying happens during the freezing stage before the drying (sublimation) process commences. A slow freezing rate leads to higher bacterial death in the subsequent sublimation stage (Uzunova-Doneva and Donev, 2002). Rapid freezing, with formation of smaller ice crystals, favours better bacterial survival. On the other hand, formation of large ice crystals during slow freezing causes structural and physiological injury to the bacterial cells and causes damage to cell membranes that cannot be repaired upon subsequent drying or rehydration (Gardiner et al., 2000).

      Many studies have exploited the addition of ‘protectant’ substances to enhance survival, and have investigated the use of low-cost food ingredients as protectants rather than substances such as glycine betaine (Cleland et al., 2004). Recent examples include work by Jagannath et al. (2010), who studied the survival of various probiotic bacteria after freeze drying. The survival obtained ranged from 67% to 70% depending on bacterial species. Zamora et al. (2006) compared the survival of twelve strains of lactic acid bacteria after freeze drying and reported a range from 3.3% to 100% depending on the bacterial type and protectant type used. For example, the survival of four strains of Lactococcus garviae was reported to be 100% when non-fat skim milk was used as the protectant (Zamora et al., 2006). Reddy et al. (2009) studied survival of three probiotic lactic acid bacteria with eleven different protectants (at various solids concentrations), and suggested that these protected not only the viability of the probiotic lactic acid bacteria but also their functional properties.

      posted in BIO204 - Principles of Biochemical Engineering
      M
      moaaz
    • RE: BT504 GDB1 Solution and discussion

      A nanopore is a nano-scale hole. In its devices, Oxford Nanopore passes an ionic current through nanopores and measures the changes in current as biological molecules pass through the nanopore or near it. The information about the change in current can be used to identify that molecule.

      Holes can be created by proteins puncturing membranes (biological nanopores) or in solid materials (solid-state nanopores).

      posted in BT504 - Genomics and Proteomics
      M
      moaaz
    • RE: BT504 GDB1 Solution and discussion

      85f20f13-db01-441e-bfc0-fb56fedd85af-image.png

      posted in BT504 - Genomics and Proteomics
      M
      moaaz
    • RE: BT504 GDB1 Solution and discussion

      A protein nanopore is set in an electrically resistant polymer membrane. An ionic current is passed through the nanopore by setting a voltage across this membrane. If an analyte passes through the pore or near its aperture, this event creates a characteristic disruption in current (as shown in the diagram below). Measurement of that current makes it possible to identify the molecule in question.

      posted in BT504 - Genomics and Proteomics
      M
      moaaz
    • RE: BIO601 GDB1 Solution and discussion

      Methods for Protein Analysis

      1. Protein Separation Methods
      2. Western Blotting
      3. Protein Identification Methods
        3A. Edman degradation
        3B. Mass spectrometry

      However, and perhaps remarkably, if as shown above we digest samples of ourprotein with as few as two or three different endoproteases with different
      specificities, we can usually use the resulting digestion patterns (again, analyzedby mass spectrometry to provide highly accurate determination of the fragmentmolecular weights) to produce a unique identification of our unknown protein:Again, mass spectrometry is uniquely well-suited for such analyses because itcan yield very accurate determinations of molecular weights from very even verysmall amounts of fragments resulting from the digestion of a particular protein.Techniques have now been developed by which proteins separated in two-dimensional gels can be digested within the gels and then injected directly into amass spectrometer for analysis of the resulting fragments.

      posted in BIO601 - Proteomics
      M
      moaaz