342 research outputs found

    Selecting and Hiring Engineers at the ABC Plant

    Get PDF
    Hiring is one of the most important duties of a manager, especially within an engineering or technical organization. Beyond the obvious reasons for selecting the proper candidate for the job, the gravity of the hiring process lies in the fact that a mistake in this area is often costly and not easily corrected. Mistakes tend to be even more costly for the ABC Plant. All positions require the ability to obtain and maintain a government security clearance. The duration of investigative activities for initial security clearances range from 3 to 6 months from initiation to completion. During this time period, and depending on their work assignment, the effectiveness of the newly hired engineer is often impeded by their lack of a security clearance. They are unable to access critical information and locations in the facility to perform their intended job function. This cost of hiring new engineers is incurred by the organization on top of the inefficiencies typical of new employee that is learning their role in a new position. If they are unable to acquire or maintain their security clearance, the engineer is not a viable option for employment and the selection and hiring process must start over again at the expense to the ABC Plant. The hiring process at the ABC Plant is generally sound, but there is room for improvement. Senior Management and Human Resources at the ABC Plant should consider increasing the amount of training around the hiring process so that Technical Managers are more confident in their ability to select the best candidate for the position. The ABC Plant needs to have an increased emphasis on the behavior of leadership impact and making a positive impact on other engineers in the organization when they screen candidates during the hiring process. In addition, the company could benefit from encouraging the existing staff to increase their leadership potential by leading small projects or becoming a mentor for a less experienced engineer. Finally, the culture at the ABC Plant is unique compared to other engineering firms. Candidates should be made aware of the mission of the facility as a manufacturer of components as opposed to design. Designs are created and controlled by a separate entity from the ABC Plant and an engineer that desires control over all aspects of the engineering process may not be a good fit for the organization

    Effect of Urea and Distillers Inclusion in Dry- Rolled Corn Based Diets on Heifer Performance and Carcass Characteristics

    Get PDF
    Crossbred heifers (n=96, BW = 810 ± 20) were utilized to evaluate the effects of increasing wet distillers grains plus solubles and urea inclusion in a dry rolled corn based finishing diet on performance and carcass characteristics. Heifers were individually fed using a calan gate system with a 2 × 2 factorial arrangement of treatments. Factors included distillers inclusion at either 10 or 20% of diet DM and urea inclusion at either 0.2 or 1.4% of diet DM. Th ere was no difference for final body weight, average daily gain, and feed conversion on a live or carcass adjusted basis for either urea or distillers inclusion in the diet. Dry matter intake was reduced with increased urea inclusion; however, distillers inclusion did not influence intake. Added distillers and urea in the diet had minimal impact on performance suggesting supplemental urea in a dry rolled corn based finishing diets is of minimal benefit when feeding at least 10% distillers grains

    Fiber-optic-based laser vapor screen flow visualization system for aerodynamic research in larger scale subsonic and transonic wind tunnels

    Get PDF
    Laser vapor screen (LVS) flow visualization systems that are fiber-optic based were developed and installed for aerodynamic research in the Langley 8-Foot Transonic Pressure Tunnel and the Langley 7- by 10-Foot High Speed Tunnel. Fiber optics are used to deliver the laser beam through the plenum shell that surrounds the test section of each facility and to the light-sheet-generating optics positioned in the ceiling window of the test section. Water is injected into the wind tunnel diffuser section to increase the relative humidity and promote condensation of the water vapor in the flow field about the model. The condensed water vapor is then illuminated with an intense sheet of laser light to reveal features of the flow field. The plenum shells are optically sealed; therefore, video-based systems are used to observe and document the flow field. Operational experience shows that the fiber-optic-based systems provide safe, reliable, and high-quality off-surface flow visualization in smaller and larger scale subsonic and transonic wind tunnels. The design, the installation, and the application of the Langley Research Center (LaRC) LVS flow visualization systems in larger scale wind tunnels are highlighted. The efficiency of the fiber optic LVS systems and their insensitivity to wind tunnel vibration, the tunnel operating temperature and pressure variations, and the airborne contaminants are discussed

    Effect of Urea and Distillers Inclusion in Dry- Rolled Corn Based Diets on Heifer Performance and Carcass Characteristics

    Get PDF
    Crossbred heifers (n=96, BW = 810 ± 20) were utilized to evaluate the effects of increasing wet distillers grains plus solubles and urea inclusion in a dry rolled corn based finishing diet on performance and carcass characteristics. Heifers were individually fed using a calan gate system with a 2 × 2 factorial arrangement of treatments. Factors included distillers inclusion at either 10 or 20% of diet DM and urea inclusion at either 0.2 or 1.4% of diet DM. Th ere was no difference for final body weight, average daily gain, and feed conversion on a live or carcass adjusted basis for either urea or distillers inclusion in the diet. Dry matter intake was reduced with increased urea inclusion; however, distillers inclusion did not influence intake. Added distillers and urea in the diet had minimal impact on performance suggesting supplemental urea in a dry rolled corn based finishing diets is of minimal benefit when feeding at least 10% distillers grains

    Multi-ingredient pre-workout supplements, safety implications, and performance outcomes: a brief review

    Get PDF
    In recent years, a new class of dietary supplements called multi-ingredient pre-workout supplements (MIPS) has increased in popularity. These supplements are intended to be taken prior to exercise and typically contain a blend of ingredients such as caffeine, creatine, beta-alanine, amino acids, and nitric oxide agents, the combination of which may elicit a synergistic effect on acute exercise performance and subsequent training adaptations compared to single ingredients alone. Therefore, the purpose of this article was to review the theoretical rationale and available scientific evidence assessing the potential ergogenic value of acute and chronic ingestion of MIPS, to address potential safety concerns surrounding MIPS supplementation, and to highlight potential areas for future research. Though direct comparisons between formulations of MIPS or between a MIPS and a single ingredient are challenging and often impossible due to the widespread use of “proprietary blends” that do not disclose specific amounts of ingredients in a given formulation, a substantial body of evidence suggests that the acute pre-exercise consumption of MIPS may positively influence muscular endurance and subjective mood, though mixed results have been reported regarding the acute effect of MIPS on force and power production. The chronic consumption of MIPS in conjunction with a periodized resistance training program appears to augment beneficial changes in body composition through increased lean mass accretion. However, the impact of long-term MIPS supplementation on force production, muscular endurance, aerobic performance, and subjective measures is less clear. MIPS ingestion appears to be relatively safe, though most studies that have assessed the safety of MIPS are relatively short (less than eight weeks) and thus more information is needed regarding the safety of long-term supplementation. As with any dietary supplement, the use of MIPS carries implications for the athlete, as many formulations may intentionally contain banned substances as ingredients or unintentionally as contaminants. We suggest that athletes thoroughly investigate the ingredients present in a given MIPS prior to consumption. In conclusion, it appears that multi-ingredient pre-workout supplements have promise as an ergogenic aid for active individuals, though further information is required regarding long-term efficacy and safety in a wider variety of populations

    Advances in restoration ecology: rising to the challenges of the coming decades

    Get PDF
    Simultaneous environmental changes challenge biodiversity persistence and human wellbeing. The science and practice of restoration ecology, in collaboration with other disciplines, can contribute to overcoming these challenges. This endeavor requires a solid conceptual foundation based in empirical research which confronts, tests and influences theoretical developments. We review conceptual developments in restoration ecology over the last 30 years. We frame our review in the context of changing restoration goals which reflect increased societal awareness of the scale of environmental degradation and the recognition that inter-disciplinary approaches are needed to tackle environmental problems. Restoration ecology now encompasses facilitative interactions and network dynamics, trophic cascades, and above- and below ground linkages. It operates in a non-equilibrium, alternative states framework, at the landscape scale, and in response to changing environmental, economic and social conditions. Progress has been marked by conceptual advances in the fields of trait-environment relationships, community assembly, and understanding the links between biodiversity and ecosystem functioning. Conceptual and practical advances have been enhanced by applying evolving technologies, including treatments to increase seed germination and overcome recruitment bottlenecks, high throughput DNA sequencing to elucidate soil community structure and function, and advances in satellite technology and GPS tracking to monitor habitat use. The synthesis of these technologies with systematic reviews of context dependencies in restoration success, model based analyses and consideration of complex socio-ecological systems will allow generalizations to inform evidence based interventions. Ongoing challenges include setting realistic, socially acceptable goals for restoration under changing environmental conditions, and prioritizing actions in an increasingly space-competitive world. Ethical questions also surround the use of genetically modified material, translocations, taxon substitutions, and de-extinction, in restoration ecology. Addressing these issues, as the Ecological Society of America looks to its next century, will require current and future generations of researchers and practitioners, including economists, engineers, philosophers, landscape architects, social scientists and restoration ecologists, to work together with communities and governments to rise to the environmental challenges of the coming decades

    Cyclic Rhamnosylated Elongation Factor P Establishes Antibiotic Resistance in \u3cem\u3ePseudomonas aeruginosa\u3c/em\u3e

    Get PDF
    Elongation factor P (EF-P) is a ubiquitous bacterial protein that is required for the synthesis of poly-proline motifs during translation. In Escherichia coli and Salmonella enterica, the posttranslational β-lysylation of Lys34 by the PoxA protein is critical for EF-P activity. PoxA is absent from many bacterial species such as Pseudomonas aeruginosa, prompting a search for alternative EF-P posttranslation modification pathways. Structural analyses of P. aeruginosa EF-P revealed the attachment of a single cyclic rhamnose moiety to an Arg residue at a position equivalent to that at which β-Lys is attached to E. coli EF-P. Analysis of the genomes of organisms that both lack poxA and encode an Arg32-containing EF-P revealed a highly conserved glycosyltransferase (EarP) encoded at a position adjacent to efp. EF-P proteins isolated from P. aeruginosa ΔearP, or from a ΔrmlC::acc1 strain deficient in dTDP-l-rhamnose biosynthesis, were unmodified. In vitro assays confirmed the ability of EarP to use dTDP-l-rhamnose as a substrate for the posttranslational glycosylation of EF-P. The role of rhamnosylated EF-P in translational control was investigated in P. aeruginosa using a Pro4-green fluorescent protein (Pro4GFP) in vivo reporter assay, and the fluorescence was significantly reduced in Δefp, ΔearP, and ΔrmlC::acc1 strains. ΔrmlC::acc1, ΔearP, and Δefp strains also displayed significant increases in their sensitivities to a range of antibiotics, including ertapenem, polymyxin B, cefotaxim, and piperacillin. Taken together, our findings indicate that posttranslational rhamnosylation of EF-P plays a key role in P. aeruginosa gene expression and survival

    An Analysis of Private School Closings

    Get PDF
    We add to the small literature on private school supply by exploring exits of K-12 private schools. We find that the closure of private schools is not an infrequent event, and use national survey data from the National Center for Education Statistics to study closures of private schools. We assume that the probability of an exit is a function of excess supply of private schools over the demand, as well as the school's characteristics such as age, size, and religious affiliation. Our empirical results generally support the implications of the model. Working Paper 07-0

    Identification and quantification of protein S-nitrosation by nitrite in the mouse heart during ischemia.

    Get PDF
    Nitrate (NO3-) and nitrite (NO2-) are known to be cardioprotective and to alter energy metabolism in vivo NO3- action results from its conversion to NO2- by salivary bacteria, but the mechanism(s) by which NO2- affects metabolism remains obscure. NO2- may act by S-nitrosating protein thiols, thereby altering protein activity. But how this occurs, and the functional importance of S-nitrosation sites across the mammalian proteome, remain largely uncharacterized. Here we analyzed protein thiols within mouse hearts in vivo using quantitative proteomics to determine S-nitrosation site occupancy. We extended the thiol-redox proteomic technique, isotope-coded affinity tag labeling, to quantify the extent of NO2--dependent S-nitrosation of proteins thiols in vivo Using this approach, called SNOxICAT (S-nitrosothiol redox isotope-coded affinity tag), we found that exposure to NO2- under normoxic conditions or exposure to ischemia alone results in minimal S-nitrosation of protein thiols. However, exposure to NO2- in conjunction with ischemia led to extensive S-nitrosation of protein thiols across all cellular compartments. Several mitochondrial protein thiols exposed to the mitochondrial matrix were selectively S-nitrosated under these conditions, potentially contributing to the beneficial effects of NO2- on mitochondrial metabolism. The permeability of the mitochondrial inner membrane to HNO2, but not to NO2-, combined with the lack of S-nitrosation during anoxia alone or by NO2- during normoxia places constraints on how S-nitrosation occurs in vivo and on its mechanisms of cardioprotection and modulation of energy metabolism. Quantifying S-nitrosated protein thiols now allows determination of modified cysteines across the proteome and identification of those most likely responsible for the functional consequences of NO2- exposure

    Considering Intra-individual Genetic Heterogeneity to Understand Biodiversity

    Get PDF
    In this chapter, I am concerned with the concept of Intra-individual Genetic Hetereogeneity (IGH) and its potential influence on biodiversity estimates. Definitions of biological individuality are often indirectly dependent on genetic sampling -and vice versa. Genetic sampling typically focuses on a particular locus or set of loci, found in the the mitochondrial, chloroplast or nuclear genome. If ecological function or evolutionary individuality can be defined on the level of multiple divergent genomes, as I shall argue is the case in IGH, our current genetic sampling strategies and analytic approaches may miss out on relevant biodiversity. Now that more and more examples of IGH are available, it is becoming possible to investigate the positive and negative effects of IGH on the functioning and evolution of multicellular individuals more systematically. I consider some examples and argue that studying diversity through the lens of IGH facilitates thinking not in terms of units, but in terms of interactions between biological entities. This, in turn, enables a fresh take on the ecological and evolutionary significance of biological diversity
    • …
    corecore