Corporate profitability and the dynamics of competition in emerging markets: a time series analysis

The paper presents time-series analyses of corporate profitability in seven leading developing countries (DCs) using the common methodology of the persistence of profitability (PP) studies and systematically compares the results with those for advanced countries (ACs). Surprisingly, both short- and long-term persistence of profitability for DCs are found to be lower than those for ACs. The paper concentrates on economic explanations for these findings. It also reports the results on the persistence of the two components of profitability - capital-output ratios and profit margins. These too raise important general issues of economic interpretation for PP studies which are outlinedCompetition, profitability, persistence, emerging markets

Experimental Performance of Reinforced and Pretensioned Precast Concrete Bent Caps

The use of precast bridge substructures provides the benefits of rapid construction, reduction of traffic disruption, increased worker safety, and increased controlled conditions within the precast plants. The Texas Department of Transportation is seeking to take a step further in the advancement of precast bent caps by implementing the use of pretensioned concrete bent caps to improve strength and serviceability in their standard bent cap bridges. The objective of this research is to provide a comparison between the performance of precast reinforced and precast pretensioned concrete bent caps. This research also focuses on construction techniques and connection details to develop serviceable recommendations for precast pretensioned bent cap specifications to be implemented by TxDOT engineers in standard bridges. An alternative connection that does not require the use of grout is investigated at the request of TxDOT engineers. Effective end region detailing to resist bursting stresses at the time of prestressing transfer is also investigated. Testing is conducted at the Texas A&M University High Bay Structural and Materials Testing Laboratory. The experimental test setup consists of a specimen subassembly representative of a TxDOT prototype bridge with load configurations capable of recreating demands in the field and also testing the specimen to failure. Material property tests are performed to calculate the expected strengths of the specimens and predict behaviors during testing. Multiple load patterns are applied to the specimens to study their behavior during bridge demands along with joint, maximum achievable moments, and failure demands. Visual observations of the damage progression are presented for each load pattern. Results from testing are analyzed to discuss the constructability and performance of the specimens in light of previous literature, to compare the results between the reinforced and pretensioned specimens, and to discuss the hierarchy of failure mechanisms. The experimental results show a superior performance of the pretensioned bent cap in comparison to the reinforced concrete bent cap. The pretensioned bent cap exhibits delayed initial cracking, smaller average crack widths and an improved ability to reduce cracks after load removal. The pocket connection performs satisfactorily for both specimens. The end-region detailing for the pretensioned specimen is efficient in controlling bursting stress cracks during the release of strands. Recommendations for field implementation include the use of the side strand configuration, the use of shrinkage admixtures for the pocket concrete, secure hold down of the pocket during construction, and the use of plastic shims and vent holes for the construction of the bedding layer

ANGLE OF ATTACK DETERMINATION USING INERTIAL NAVIGATION SYSTEM DATA FROM FLIGHT TESTS

Engineers and pilots rely on mechanical flow angle vanes on air data probes to determine the angle of attack of the aircraft in flight. These probes, however, are costly, come with inherent measurement errors, affect the flight characteristics of the aircraft, and are potentially dangerous in envelope expansion flights. Advances in the accuracy, usability, and affordability of inertial navigation systems allow for angle of attack to be determined accurately without direct measurement of the airflow around the aircraft. Utilizing an algorithm developed from aircraft equations of motion, a post-flight data review is completed as the first step in proving the low cost feasibility of utilizing inertial navigation data for such analysis. Flight tests were conducted with the UTSI Cessna 210 research aircraft to calibrate an angle of attack flow angle vane and obtain inertial navigation data from a commercial INS system in typical flight scenarios. The results of the angle of attack algorithm are compared to the measured angle of attack flow angle vane. Discussed in this thesis are the feasibility and potential applications of angle of attack determination from inertial data

Experimental Performance of Reinforced and Pretensioned Precast Concrete Bent Caps

The use of precast bridge substructures provides the benefits of rapid construction, reduction of traffic disruption, increased worker safety, and increased controlled conditions within the precast plants. The Texas Department of Transportation is seeking to take a step further in the advancement of precast bent caps by implementing the use of pretensioned concrete bent caps to improve strength and serviceability in their standard bent cap bridges. The objective of this research is to provide a comparison between the performance of precast reinforced and precast pretensioned concrete bent caps. This research also focuses on construction techniques and connection details to develop serviceable recommendations for precast pretensioned bent cap specifications to be implemented by TxDOT engineers in standard bridges. An alternative connection that does not require the use of grout is investigated at the request of TxDOT engineers. Effective end region detailing to resist bursting stresses at the time of prestressing transfer is also investigated. Testing is conducted at the Texas A&M University High Bay Structural and Materials Testing Laboratory. The experimental test setup consists of a specimen subassembly representative of a TxDOT prototype bridge with load configurations capable of recreating demands in the field and also testing the specimen to failure. Material property tests are performed to calculate the expected strengths of the specimens and predict behaviors during testing. Multiple load patterns are applied to the specimens to study their behavior during bridge demands along with joint, maximum achievable moments, and failure demands. Visual observations of the damage progression are presented for each load pattern. Results from testing are analyzed to discuss the constructability and performance of the specimens in light of previous literature, to compare the results between the reinforced and pretensioned specimens, and to discuss the hierarchy of failure mechanisms. The experimental results show a superior performance of the pretensioned bent cap in comparison to the reinforced concrete bent cap. The pretensioned bent cap exhibits delayed initial cracking, smaller average crack widths and an improved ability to reduce cracks after load removal. The pocket connection performs satisfactorily for both specimens. The end-region detailing for the pretensioned specimen is efficient in controlling bursting stress cracks during the release of strands. Recommendations for field implementation include the use of the side strand configuration, the use of shrinkage admixtures for the pocket concrete, secure hold down of the pocket during construction, and the use of plastic shims and vent holes for the construction of the bedding layer

Chronic toxicity of inhaled thymol in lungs and respiratory tracts in mouse model.

Epinephrine HFA (Primatene® Mist) is a newly formulated asthma metered dose inhaler developed to replace the previous Primatene® Mist CFC. The formulation of Epinephrine HFA contains thymol, a substance recognized to be safe by the FDA. Although the content of thymol contained in Epinephrine HFA is much lower compared to many common foods and medications available, there are no known nonclinical data about the chronic toxicity of thymol through inhalation. Two sequential 6-month studies of identical design were conducted to assess the chronic toxicity of inhaled thymol in mice. Four treatment groups, (a) Air; (b) vehicle control; (c) Article-1 (thymol 0.1%); and (d) Article-2 (thymol 0.5%) were assessed in 128 mice for 26 weeks. The mice were sacrificed at the end of the treatment period and a histopathologic evaluation was performed with respect to lungs, bronchial lymph nodes, nasal passages/nasopharynx, and trachea. Forty-five pathologic assessment parameters (PAPs) were evaluated. In total, 5591 data points from 487 mouse organs were assessed. Chronic toxicity index was calculated for 16 PAPs that had multiple histopathologic abnormal observations. The t tests were conducted for these 16 PAPs (Articles-1 and 2 versus Air and vehicle control, respectively), and all P-values were greater than .05 indicating no significant differences between all treatment groups. An evaluation was also conducted for 25 PAPs that had only a very small number of pathologic abnormalities. No significant differences for chronic toxicity were found when comparing mice under long-term repeated exposure of high doses of inhaled thymol and mice that inhaled no thymol

Pharmacokinetic study of thymol after intravenous injection and high-dose inhalation in mouse model.

Thymol is generally recognized as a safe substance by the FDA and has been widely used in the pharmaceutical, food, and cosmetic industries. Pharmacokinetic (PK) studies of thymol have been previously conducted for oral administration, but there has been no PK study for inhalation administration or intravenous (IV) injection. This study aims at exploring and comparing the inhalation and IV PK profile of thymol in a mouse model. The inhalation PK for mouse model was corrected with fur/skin absorption. Thirty-two male CD-1 mice were randomized into two study arms, Arm-A for intravenous (n = 16) and Arm-B for inhalation (n = 16). The amount of thymol in the mouse serum was measured for Arm-A and for Arm-B at the highest dose. Furthermore, 48 mice were utilized for fur/skin absorption of thymol. In total, 320 mouse serum samples for thymol were analyzed by LC/MS method. After inhalation, the peak concentration of thymol in mouse serum was 42.3 ng/mL (Cmax ) and occurred at 2 minutes (tmax ). The AUC of the inhaled thymol at 0-60 minutes (AUC0-60) was 464 ng/mL/min. From 10-60 minutes post-dose, the PK inhalation curve appeared to be higher than that for the IV injection. This is likely attributed to the effect of absorption of thymol through the fur/skin of mice. After an adjustment by fur/skin absorption, the PK profile for net inhalation closely matched the two-compartment model. In fact, the bioavailability for the net inhalation of thymol was 74% and 77% relative to that for IV injection per AUC0-60min and AUC0-infinite, respectively

Variability of Temperature and Salinity in the Middle Atlantic Bight and Gulf of Maine

Monitoring of the waters of the Middle Atlantic Bight and Gulf of Maine has been conducted by the MARMAP Ships of Opportunity Program since the early 1970's. Presented in this atlas are portrayals of the temporal and spatial patterns of surface and bottom temperature and surface salinity for these areas during the period 1978-1990. These patterns are shown in the form of time-space diagrams for single-year and multiyear (base period) time frames. Each base period figure shows thirteen-year (1978-1990) mean conditions, sample variance in the form of standard deviations of the measured values, and data locations. Each single-year figure displays annual conditions, sampling locations, and departures of annual conditions from the thirteen-year means, expressed as algebraic anomalies and standardized anomalies. (PDF file contains 112 pages.

Material Issues in Layered Forming

A brief overview of key issues in layered thermal processing is given. Incremental sintering and layered fusion ofpowder and molten droplets are discussed. The criteria for remelting the solid substrate are derivedfrom a one dimensional heat transfer model. Temperature gradients which occur during solidification and subsequent cooling. are responsible for the build up of internal stresses which can be estimated through establishing an elastic beam model. The difficulties as well as opportunities regarding the generation of multi-layer multi-material structures are also described in this article.Mechanical Engineerin

'Encore' Red Raspberry

'Encore' is a new red raspberry developed by Cornell University at the New York State Agricultural Experiment Station in Geneva, New York. 'Encore' is outstanding for its consistent performance over many years of testing. 'Encore' is a late season red raspberry cultivar developed for growers interested in increasing their late season production. Specifically, it has excellent winter hardiness in zone 5, very good plant production and vigor, and commercial yields of large size fruit that peak in production late in the harvest season. 'Encore' is adapted to upick, retail, and wholesale markets. Its firm fruit withstand handling and packing to produce an attractive pack for resale. 'Encore' has potential to become a leading red raspberry cultivar in the East Coast and Great Lakes regions

Synthetic control of a fitness tradeoff in yeast nitrogen metabolism

Background: Microbial communities are involved in many processes relevant to industrial and medical biotechnology, such as the formation of biofilms, lignocellulosic degradation, and hydrogen production. The manipulation of synthetic and natural microbial communities and their underlying ecological parameters, such as fitness, evolvability, and variation, is an increasingly important area of research for synthetic biology. Results: Here, we explored how synthetic control of an endogenous circuit can be used to regulate a tradeoff between fitness in resource abundant and resource limited environments in a population of Saccharomyces cerevisiae. We found that noise in the expression of a key enzyme in ammonia assimilation, Gdh1p, mediated a tradeoff between growth in low nitrogen environments and stress resistance in high ammonia environments. We implemented synthetic control of an endogenous Gdh1p regulatory network to construct an engineered strain in which the fitness of the population was tunable in response to an exogenously-added small molecule across a range of ammonia environments. Conclusion: The ability to tune fitness and biological tradeoffs will be important components of future efforts to engineer microbial communities