Microbial survival after isoelectric solubilization and precipitation of fish protein

Protein wasted by the disposal of fish processing byproducts may be recovered using isoelectric solubilization and precipitation. The protein is dissolved by extreme pH shifts and recovered via precipitation and centrifugation. Microbial safety throughout this process had not yet been evaluated; therefore, the purpose of this study was to determine if Listeria innocua and Escherichia coli would survive extreme pH shifts during the protein recovery process. Fresh rainbow trout were headed, gutted, and minced and then inoculated with 109 CFU/g E. coli ATCC 25922 or filleted and minced and then inoculated with 109 cfu/g of L. innocua. The fish was homogenized and brought to the target pH of 2.0, 3.0, 11.5 or 12.5 by the addition of concentrated hydrochloric acid or sodium hydroxide to solubilize the muscle proteins. The homogenate was blended at 4°C for 10 min and centrifuged to separate the lipid and insoluble components (bones, skin, insoluble protein, etc.) from the protein solution. The lipid and insoluble components were removed and the protein solution was subjected to a second pH shift (pH 5.5) resulting in protein precipitation. Centrifugation was applied to separate the precipitated proteins from the water. Each constituent (i.e., lipid, insoluble components, protein, and water) was analyzed for bacterial content using non-selective growth media and selective media. The sums of the surviving bacteria in these fractions were compared to the initial inoculum. For L. innocua there were no significant differences in recovery on growth or selective media (P \u3e 0.05); implying both acidic and basic conditions have an all-or-nothing bactericidal effect on the gram-positive species. The greatest overall microbial reduction occurred when the pH was shifted to 2.0: a total of 3-log reduction in microbes. Compared to the initial inoculum level in the trout filets, there was a 4-log reduction of Listeria cells in recovered protein. For E. coli, the greatest total microbial reduction occurred when the pH was shifted to 12.5 (P \u3c 0.05): a 4.4-log reduction of cells on growth media and a 6.0-log reduction of cells on selective media. Compared to the initial inoculum level in the minced trout, there was a 4.7-log reduction of E. coli cells in recovered protein on selective media. There was significant (P \u3c 0.05) injury sustained by cells exposed to alkaline treatment (pH 11.5 and 12.5) in all fractions except the insoluble fraction at pH 11.5. Increasing the exposure time or the pH, or using a weak organic acid in lieu of a strong acid for Listeria, may result in greater bacterial reductions in the recovered protein

The Walkout

This short essay explores the author\u27s memories of participating in a school walkout to protest gun violence

Comparative Analysis between Vaccine Hesitancy and Rural vs Non-Rural Counties in the South-East Region

Throughout the United States (U.S) there is a variety of people who are hesitant to get the COVID vaccine. Research was collected on April 14,2021 by the Center of Disease Control and Prevention, at a county level for each state. The data depicted this by showing different levels of vaccine hesitancy: “strongly hesitant,” “hesitant,” and “unsure.” Participants could choose between five options: “definitely get a vaccine,” “probably get a vaccine,” “unsure,” “probably not get a vaccine,” and “definitely not get a vaccine” . Strongly hesitant included those who only responded they would “definitely not” get the vaccine. We decided with this information to only use the “Strongly hesitant” variable for our data. We used this data to look at the South-east region of the United States, specifically Georgia, Florida, South Carolina, Alabama, and Tennessee. Overall, the purpose of our study is to determine whether there is a difference between vaccine hesitancy and a county being rural vs. non-rural. Using the U.S Department of Agriculture definition of rural, 500 people or less is considered rural per square mile and anything more than 500 people per square mile is considered non-rural. Then we will identify the counties that are rural and the amount of vaccine hesitancy and the non-rural with their vaccine hesitancy. We will be using our data to make statistical graphs to identify the different sizes of rural and non-rural areas. Using this data, we will compare both data of vaccine hesitancy to see if there is a difference between the levels of hesitancy in rural vs. non-rural counties. In conclusion, we expect our data to show that there is a difference in the vaccine hesitancy and of a county being defined as rural or non-rural. This study can help improve our understanding of each county and be able to identify more relationships between health decisions in each county

Theoretical Accuracy for ESTL Bit Error Rate Tests

"Bit error rate" [BER] for the purposes of this paper is the fraction of binary bits which are inverted by passage through a communication system. BER can be measured for a block of sample bits by comparing a received block with the transmitted block and counting the erroneous bits. Bit Error Rate [BER] tests are the most common type of test used by the ESTL for evaluating system-level performance. The resolution of the test is obvious: the measurement cannot be resolved more finely than 1/N, the number of bits tested. The tolerance is not. This paper examines the measurement accuracy of the bit error rate test. It is intended that this information will be useful in analyzing data taken in the ESTL. This paper is divided into four sections and follows a logically ordered presentation, with results developed before they are evaluated. However, first-time readers will derive the greatest benefit from this paper by skipping the lengthy section devoted to analysis, and treating it as reference material. The analysis performed in this paper is based on a Probability Density Function [PDF] which is developed with greater detail in a past paper, Theoretical Accuracy for ESTL Probability of Acquisition Tests, EV4-98-609

External Wireless Communication System Status for POIWG

No abstract availabl

Assessing the credibility of organized volunteer crisis mappers

Thesis (M.C.P.)--Massachusetts Institute of Technology, Department of Urban Studies and Planning, 2013.This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.Cataloged from student-submitted PDF version of thesis. "September 2013."Includes bibliographical references (pages 36-38).In the past decade humanitarian crises have been occurring with increasing frequency. As of 2013 the United Nations Office for the Coordination of Humanitarian Affairs (UN OCHA) is involved in 27 countries, monitoring the response to natural disasters or violent conflict (Where we work n.d.). Over the same period the internet has seen a deluge of new, interactive website and tools. Social media sites that allow users to share their own content with a digital community have led to an explosion of user-generated content online. Meanwhile, internet-based mapping tools, such as Google Maps, make it easy for almost anyone to make maps online. These developments converge in the form of a recent trend: volunteer crisis mapping. Since 2008 individuals have started making maps and collecting spatial data related to humanitarian crises -both violent conflicts and natural disasters. While the role of social media and web-mapping in humanitarian responses has been praised for creating a participatory space in humanitarian responses, the people volunteering to do the crisis mapping remain largely unexplored. Drawing from the neogeography literature which explores the impact amateur mappers in general, this paper seeks to define who the volunteer crisis mappers are, and how they are forming institutional connections to the 'formal' humanitarian sector.by Elizabeth Resor.M.C.P

Jitter Controller Software

Sinusoidal jitter is produced by simply modulating a clock frequency sinusoidally with a given frequency and amplitude. But this can be expressed as phase jitter, frequency jitter, or cycle-to-cycle jitter, rms or peak, absolute units, or normalized to the base clock frequency. Jitter using other waveforms requires calculating and downloading these waveforms to an arbitrary waveform generator, and helping the user manage relationships among phase jitter crest factor, frequency jitter crest factor, and cycle-to-cycle jitter (CCJ) crest factor. Software was developed for managing these relationships, automatically configuring the generator, and saving test results documentation. Tighter management of clock jitter and jitter sensitivity is required by new codes that further extend the already high performance of space communication links, completely correcting symbol error rates higher than 10 percent, and therefore typically requiring demodulation and symbol synchronization hardware to operating at signal-to-noise ratios of less than one. To accomplish this, greater demands are also made on transmitter performance, and measurement techniques are needed to confirm performance. It was discovered early that sinusoidal jitter can be stepped on a grid such that one can connect points by constant phase jitter, constant frequency jitter, or constant cycle-cycle jitter. The tool automates adherence to a grid while also allowing adjustments off-grid. Also, the jitter can be set by the user on any dimension and the others are calculated. The calculations are all recorded, allowing the data to be rapidly plotted or re-plotted against different interpretations just by changing pointers to columns. A key advantage is taking data on a carefully controlled grid, which allowed a single data set to be post-analyzed many different ways. Another innovation was building a software tool to provide very tight coupling between the generator and the recorded data product, and the operator's worksheet. Together, these allowed the operator to sweep the jitter stimulus quickly along any of three dimensions and focus on the response of the system under test (response was jitter transfer ratio, or performance degradation to the symbol or codeword error rate). Additionally, managing multi-tone and noise waveforms automated a tedious manual process, and provided almost instantaneous decision- making control over test flow. The code was written in LabVIEW, and calls Agilent instrument drivers to write to the generator hardware

Brave spirits on new paths : toward a globally relevant paradigm of Indigenous entrepreneurship research

This is the first study in a series aimed at strengthening research in the emerging field of Indigenous entrepreneurship. A literature survey revealed two dominant themes: the need to reconcile tradition with innovation and the need to understand how Indigenous world-views and values impact upon enterprise. Four relevant theoretical contexts guided an empirical investigation employing depth interviews with 40 selected opinion leaders representing two cultures: Indigenous Australian and American Indian. Data evaluation culminated in the formal articulation of a paradigm for Indigenous entrepreneurship research. Discussion focused on utility of the paradigm and future research directions.<br /

Brave spirits on new paths : toward a globally relevant paradigm of indigenous entrepreneurship research

This is the first study in a series aimed at strengthening research in the emerging field of Indigenous entrepreneurship. A literature survey revealed two dominant themes: the need to reconcile tradition with innovation and the need to understand how Indigenous world-views and values impact upon enterprise. Four relevant theoretical contexts guided an empirical investigation employing depth interviews with 40 selected opinion leaders representing two cultures: Indigenous Australian and American Indian. Data evaluation culminated in the formal articulation of a paradigm for Indigenous entrepreneurship research. Discussion focused on utility of the paradigm and future research directions.<br /

Experimental Applications of Automatic Test Markup Language (ATML)

The authors describe challenging use-cases for Automatic Test Markup Language (ATML), and evaluate solutions. The first case uses ATML Test Results to deliver active features to support test procedure development and test flow, and bridging mixed software development environments. The second case examines adding attributes to Systems Modelling Language (SysML) to create a linkage for deriving information from a model to fill in an ATML document set. Both cases are outside the original concept of operations for ATML but are typical when integrating large heterogeneous systems with modular contributions from multiple disciplines