Consumer expenditure on food away from home in the United States has grown substantially in recent decades. Changes in the food service system, increased complexity of family structure, and the food policies made by government agencies have continued to influence the marketing, distribution, retailing, and demand for food products and the food industry. This study explores consumption behavior on food away from home (FAFH) and determines the differentiated impacts of economic and demographic variables on FAFH by type of meal and by type of facility among different household types. Each of the two systems of expenditures is estimated with two alternative econometric procedures to accommodate censoring in the dependent variables: the trivariate Tobit estimator and the multivariate sample selection estimator. Data for this study come from the 2008 and 2009 Consumer Expenditure Surveys, the most recent U.S. national household expenditure surveys conducted by the Bureau of Labor Statistics. Joint statistical significance of error correlations among equations justifies estimation of the sample selection systems. The opposite marginal effects on probabilities and expenditure levels of some variables highlight the advantage of the sample selection system over the Tobit system. Segmentation of the sample by household types is also justified with formal statistical tests. The empirical results indicate that the effects of demographic and socioeconomic factors on FAFH consumption vary by type of meal and by type of facility. Income, work hours, race, education, geographical region, and household composition are important factors. Food stamps have no impact on FAFH for married couples without children and single parenthood has conflicting effects on probabilities and conditional levels of expenditures.

<p>Synthetic biology reprograms organisms to perform non-native functions for beneficial reasons. An important practice in synthetic biology is the ability to edit DNA to change a base pair, disrupt a gene, or insert a new DNA sequence. DNA edits are commonly made with the help of homologous recombination, which inserts new DNA flanked by sequences homologous to the target region. To increase homologous recombination efficiency, a double stranded break is needed in the middle of the target sequence. Common methods to induce double stranded breaks use nucleases, enzymes that cleave ribonucleotides (DNA and RNA). The most common nucleases are restriction enzymes, which recognize a short, fixed, palindromic DNA sequence (4-8 base pairs). Because of the short and fixed nature of the recognition sites, restriction enzymes do not make good candidates to edit large chromosomal DNA. Alternatively, scientists have turned to programmable endonucleases which recognize user-defined DNA sequences, often times much larger than the recognition sites of restriction enzymes (15-25 base pairs). Programmable endonucleases such as CRISPR-based systems and prokaryotic Argonautes are found throughout the prokaryotic kingdom and may differ significantly in activity and specificity. To compare activity levels among endonuclease enzymes, activity assays are needed. These assays must clearly delineate dynamic activity levels of different endonucleases and work with a wide variety of enzymes. Ideally, the activity assay will also function as a positive selection screen, allowing modifications to the enzymes via directed evolution. Here, we develop an <i>in vivo</i> assay for programmable endonuclease activity that can also serve as a positive selection screen using two plasmids, a lethal plasmid to cause cell death and a rescue plasmid to rescue cell growth. The lethal plasmid houses the homing endonuclease, I-SceI, which causes a deadly double-stranded break at an 18 base pair sequence inserted into an engineered <i>E. coli</i> genome. The rescue plasmid encodes for a chosen endonuclease designed to target and cleave the lethal plasmid, thereby preventing cell death. With this, cell growth is directly linked to programmable endonuclease activity. Three endonucleases were tested, SpCas9, eSpCas9, and xCas9, displaying recovered growth of 49.3%, 26.1%, and 16.4% respectively. These values translate to kinetic enzymatic activity and are congruent with current literature findings as reported values find WT-SpCas9 to have the fastest kinetics cleaving around 95% of substrate within 15 seconds, followed closely by eSpCas9 cleaving 75% of substrate within 15 seconds and finally trailed by xCas9 cleaving 20% of substrate in about 30 seconds. The differences between each endonuclease’s activity is exacerbated in our <i>in vivo</i> system when compared to similar <i>in vitro</i> methods with much lower resolution. Therefore, slight differences in activity between endonucleases within the first few minutes in an <i>in vitro</i> assay may be a few percentages different whereas in our <i>in vivo</i> assay, these differences in activity result in a more amplified signal. With the ability to display the dynamic response of enzymes, this assay can be used to compare activity levels between endonucleases, give insight into their kinetics, and serve as a positive selection screen for use in directed evolution applications. </p>

Over the last two decades, the use of professional designations as selection criteria has increased. In order to develop selection criteria, recruiters assess candidates from both job and organizational perspectives (Kristof-Brown 2000). No research exists that examines the degree to which organizational objectives, rooted in considerations that are not job-specific, may be affecting the increase in demand for these designations. This research attempts to close that gap by exploring the relationships among organizational objectives, the design of selection criteria, and the use of voluntary professional designations. The study explores the degree to which organizations use voluntary professional designations to assess person-organization (P-O) fit in environments emphasizing two objectives related to superior firm performance: the acquisition of competencies related to sustainable competitive advantages (SCAs) (Barney 1991; Porter 1985), and the development of characteristics associated with a high performance workplace culture (Huselid and Becker 1997). It also explores the extent to which a needs-supplies selection perspective is related to conceptualizations of P-O fit that are separate from notions of person-job (P-J) fit (Kristof 1996). Data were obtained from a sample of 292 HR professionals, representing a cross section of industries, who completed a Web-based survey. Confirmatory factor analysis revealed the presence of positive and significant relationships between each of three organizational contingencies (i.e., a needs-supplies perspective, a high performance workplace system culture, the desire to acquire competencies perceived to be sustainable competitive advantages) and the construct of P-O fit. Perceptions that the competencies were inimitable had the strongest relationship to P-O fit. As well, a positive and significant relationship was found between the construct of P-O fit and the use of a professional designation. However, study results also indicated that only two dimensions of SCA were positively and significantly related to the use of a professional designation: perceptions that the competencies represented by the designation are rare, and perceptions that they add long-term value.

Over the last two decades, the use of professional designations as selection criteria has increased. In order to develop selection criteria, recruiters assess candidates from both job and organizational perspectives (Kristof-Brown 2000). No research exists that examines the degree to which organizational objectives, rooted in considerations that are not job-specific, may be affecting the increase in demand for these designations. This research attempts to close that gap by exploring the relationships among organizational objectives, the design of selection criteria, and the use of voluntary professional designations. The study explores the degree to which organizations use voluntary professional designations to assess person-organization (P-O) fit in environments emphasizing two objectives related to superior firm performance: the acquisition of competencies related to sustainable competitive advantages (SCAs) (Barney 1991; Porter 1985), and the development of characteristics associated with a high performance workplace culture (Huselid and Becker 1997). It also explores the extent to which a needs-supplies selection perspective is related to conceptualizations of P-O fit that are separate from notions of person-job (P-J) fit (Kristof 1996). Data were obtained from a sample of 292 HR professionals, representing a cross section of industries, who completed a Web-based survey. Confirmatory factor analysis revealed the presence of positive and significant relationships between each of three organizational contingencies (i.e., a needs-supplies perspective, a high performance workplace system culture, the desire to acquire competencies perceived to be sustainable competitive advantages) and the construct of P-O fit. Perceptions that the competencies were inimitable had the strongest relationship to P-O fit. As well, a positive and significant relationship was found between the construct of P-O fit and the use of a professional designation. However, study results also indicated that only two dimensions of SCA were positively and significantly related to the use of a professional designation: perceptions that the competencies represented by the designation are rare, and perceptions that they add long-term value.

Hepatitis C virus (HCV) is a worldwide spread pathogen infecting up to 3 % of the human population. Nowadays, research of new drugs against this virus is focused on the individual steps in its life cycle, including the translation initiation. In the case of HCV translation initiation is dependent on the internal ribosome entry site (IRES). Besides of components of the translational machinery also other components of the cell, so called IRES trans-acting factors (ITAF), contribute to its proper progress. This work continues in previous research of our laboratory focused on searching for new ITAF. In order to search for potential ITAF increasing HCV IRES activity new recombinant plasmid vectors and reference strains were prepared and selection conditions of the selection system were optimized. The differences in the growth characteristics of the reference strains were analyzed and quantified under selective and non-selective conditions. A set of pilot high efficiency transformations of the yeast strain pJ69-4A carrying bicistronic construct with HCV IRES were conducted using human expression cDNA library in order to optimize the efficiency of transformation and selection conditions and to attempt to identify new ITAF. Several dozens of randomly selected clones from these transformations obtained under...