The use of site-directed mutagenesis to study GPCRs

G protein coupled receptors (GPCRs) are highly flexible and dynamic proteins, which are able to interact with diverse ligands, effectors, and regulatory proteins. Site-directed mutagenesis (SDM) is a powerful tool for providing insight into how these proteins actually work, both in its own right and when used in conjunction with information provided by other techniques such as crystallography or molecular modelling. Mutagenesis has been used to identify and characterise a myriad of functionally important residues, motifs and domains within the GPCR architecture, and to identify aspects of similarity and differences between the major families of GPCRs. This chapter presents the necessary information for undertaking informative SDM of these proteins. Whilst this is relevant to protein structure/function studies in -general, specific pitfalls and protocols suited to investigating GPCRs in particular will be highlighted.

Vector solitons with locked and precessing states of polarization

We demonstrate experimentally new families of vector solitons with locked and precessing states of polarization for fundamental and multipulse soliton operations in a carbon nanotube mode-locked fiber laser with anomalous dispersion laser cavity.

Appropriate wage rate and estimate of labour availability for a public works based safety net in Cambodia

Employment generating public works (EGPW) are an important part of Royal Government of Cambodia’s (RGC’s) strategy being developed through Council for Agriculture and Rural Development (CARD) to develop a comprehensive social safety net (SSN) to provide a measure of protection from shocks for the poor and vulnerable and to contribute to poverty alleviation through short-term unskilled employment.

Mesoporous silicas as versatile supports to tune the palladium-catalyzed selective aerobic oxidation of allylic alcohols

Surfactant templating offers a simple route to synthesize high-surface area silicas with ordered, tunable mesopore architectures. The use of these materials as versatile catalyst supports for palladium nanoparticles has been explored in the aerobic selective oxidation (selox) of allylic alcohols under mild conditions. Families of Pd/mesoporous silicas, synthesized through incipient wetness impregnation of SBA-15, SBA-16, and KIT-6, have been characterized by using nitrogen porosimetry, CO chemisorption, diffuse reflection infrared Fourier transform spectroscopy, X-ray diffraction, X-ray photoelectron spectroscopy, X-ray absorption spectroscopy, and high-resolution TEM and benchmarked in liquid phase allylic alcohol selox against a Pd/amorphous SiO2 standard. The transition from amorphous to two-dimensional parallel and three-dimensional interpenetrating porous silica networks conferred significant selox rate enhancements associated with higher surface densities of active palladium oxide sites. Dissolved oxygen was essential for insitu stabilization of palladium oxide, and thus maintenance of high activity on-stream, whereas selectivity to the desired aldehyde selox product over competing hydrogenolysis pathways was directed by using palladium metal. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

The rise and fall of diasporic bonds in Japanese-Peruvian “Return” migration

Two decades after Japanese-Peruvians and other South Americans of Japanese descent began to migrate back to Japan, the return-migration phenomenon has ended. Induced by the Japanese government in the name of shared ethnicity, Japanese policymakers now largely regard return migration as a failed policy. It failed because return-migrants did not, in the view of policy- makers, assimilate, integrate, or “make it” in Japan as expected. Thus, once-imagined ethnic bonds ceased to exist in Japan. However, ethnic bonds sustained themselves well outside Japan. The Japanese-Peruvian community in Peru has thrived and maintained continuous ties with Japan. What explains the rise and fall of diasporic ethnic bonds? Drawing on my ethnographic research in Japanese-Peruvian communities in Peru and Japan, I found that diasporic ethnic bonds are cultivated or weakened depending upon where diasporic populations are located in relation to their ancestral homeland, and how such ties are utilized, for what, and by whom.

On Averaging Null Sequences of Real-Valued Functions

If ξ is a countable ordinal and (fk) a sequence of real-valued functions we define the repeated averages of order ξ of (fk). By using a partition theorem of Nash-Williams for families of finite subsets of positive integers it is proved that if ξ is a countable ordinal then every sequence (fk) of real-valued functions has a subsequence (f'k) such that either every sequence of repeated averages of order ξ of (f'k) converges uniformly to zero or no sequence of repeated averages of order ξ of (f'k) converges uniformly to zero. By the aid of this result we obtain some results stronger than Mazur’s theorem.

On a Class of Generalized Elliptic-type Integrals

The aim of this paper is to study a generalized form of elliptic-type integrals which unify and extend various families of elliptic-type integrals studied recently by several authors. In a recent communication [1] we have obtained recurrence relations and asymptotic formula for this generalized elliptic-type integral. Here we shall obtain some more results which are single and multiple integral formulae, differentiation formula, fractional integral and approximations for this class of generalized elliptic-type integrals.

Polynomials of Pellian Type and Continued Fractions

We investigate infinite families of integral quadratic polynomials {fk (X)} k∈N and show that, for a fixed k ∈ N and arbitrary X ∈ N, the period length of the simple continued fraction expansion of √fk (X) is constant. Furthermore, we show that the period lengths of √fk (X) go to infinity with k. For each member of the families involved, we show how to determine, in an easy fashion, the fundamental unit of the underlying quadratic field. We also demonstrate how the simple continued fraction ex- pansion of √fk (X) is related to that of √C, where √fk (X) = ak*X^2 +bk*X + C. This continues work in [1]–[4].

On Hankel Transform of Generalized Mathieu Series

Mathematics Subject Classification: Primary 33E20, 44A10; Secondary 33C10, 33C20, 44A20

Multipulse vector solitons with precessing states of polarization

We demonstrate experimentally new families of vector solitons with the precessing states of polarization for multipulse soliton operations in a carbon nanotube mode-locked fiber laser with anomalous dispersion laser cavity. © 2013 OSA.

An automated method for the determination of electroreception thresholds in weakly electric fish

Weakly electric fish produce a dual function electric signal that makes them ideal models for the study of sensory computation and signal evolution. This signal, the electric organ discharge (EOD), is used for communication and navigation. In some families of gymnotiform electric fish, the EOD is a dynamic signal that increases in amplitude during social interactions. Amplitude increase could facilitate communication by increasing the likelihood of being sensed by others or by impressing prospective mates or rivals. Conversely, by increasing its signal amplitude a fish might increase its sensitivity to objects by lowering its electrolocation detection threshold. To determine how EOD modulations elicited in the social context affect electrolocation, I developed an automated and fast method for measuring electroreception thresholds using a classical conditioning paradigm. This method employs a moving shelter tube, which these fish occupy at rest during the day, paired with an electrical stimulus. A custom built and programmed robotic system presents the electrical stimulus to the fish, slides the shelter tube requiring them to follow, and records video of their movements. I trained the electric fish of the genus Sternopygus was trained to respond to a resistive stimulus on this apparatus in 2 days. The motion detection algorithm correctly identifies the responses 91% of the time, with a false positive rate of only 4%. This system allows for a large number of trials, decreasing the amount of time needed to determine behavioral electroreception thresholds. This novel method enables the evaluation the evolutionary interplay between two conflicting sensory forces, social communication and navigation.

The use of the Dade County student assistance profile in the identification of at -risk students at a minority senior high school

Current high school completion rates in Dade County and across the nation are considered to be unacceptable. This has led to the development of student assistance profiles to aid in the early identification of students considered to be at risk to allow for some form of intervention. The purpose of this research was to examine the current Dade County Public Schools profile as applied to one specific high school in which most of the students are Hispanic (mostly of Mexican descent) and Black (African-Americans, as well as recent Haitian immigrants). Additionally, the effectiveness of the alternative intervention program provided at this high school--a school within a school--were evaluated. School records of the 1992 in-coming ninth grade class became the initial data base. The individual student records of this cohort were then examined over a four-year period until their expected date or graduation. The DCPS profile used to identify potential dropouts from this group was evaluated, using chi-square and multivariate analysis, to determine its overall effectiveness, as well as the effectiveness of the individual indicators which comprise the profile. The Student Assistance Profile was found to an effective predictor, but it over-identified students from this cohort, particularly minorities, to the extent that it became largely ineffective, especially considering the limited resources available for intervention. The intervention program was found to be ineffective in reducing the dropout rate. Further analysis of the individual indicators used in the DCPS profile as they applied to this school population resulted in the development of an improved profile. By reducing the number of indicators to those found to be most highly associated with failure to graduate--academic performance and absences--a simpler student assistance profile was developed which appears to be better suited to high schools with similar demographics and budget restraints. ^

Novel analytical methodologies for the monitoring of traditional and non-traditional pollutants in different environmental compartments of South Florida

Routine monitoring of environmental pollution demands simplicity and speed without sacrificing sensitivity or accuracy. The development and application of sensitive, fast and easy to implement analytical methodologies for detecting emerging and traditional water and airborne contaminants in South Florida is presented. A novel method was developed for quantification of the herbicide glyphosate based on lyophilization followed by derivatization and simultaneous detection by fluorescence and mass spectrometry. Samples were analyzed from water canals that will hydrate estuarine wetlands of Biscayne National Park, detecting inputs of glyphosate from both aquatic usage and agricultural runoff from farms. A second study describes a set of fast, automated LC-MS/MS protocols for the analysis of dioctyl sulfosuccinate (DOSS) and 2-butoxyethanol, two components of Corexit®. Around 1.8 million gallons of those dispersant formulations were used in the response efforts for the Gulf of Mexico oil spill in 2010. The methods presented here allow the trace-level detection of these compounds in seawater, crude oil and commercial dispersants formulations. In addition, two methodologies were developed for the analysis of well-known pollutants, namely Polycyclic Aromatic Hydrocarbons (PAHs) and airborne particulate matter (APM). PAHs are ubiquitous environmental contaminants and some are potent carcinogens. Traditional GC-MS analysis is labor-intensive and consumes large amounts of toxic solvents. My study provides an alternative automated SPE-LC-APPI-MS/MS analysis with minimal sample preparation and a lower solvent consumption. The system can inject, extract, clean, separate and detect 28 PAHs and 15 families of alkylated PAHs in 28 minutes. The methodology was tested with environmental samples from Miami. Airborne Particulate Matter is a mixture of particles of chemical and biological origin. Assessment of its elemental composition is critical for the protection of sensitive ecosystems and public health. The APM collected from Port Everglades between 2005 and 2010 was analyzed by ICP-MS after acid digestion of filters. The most abundant elements were Fe and Al, followed by Cu, V and Zn. Enrichment factors show that hazardous elements (Cd, Pb, As, Co, Ni and Cr) are introduced by anthropogenic activities. Data suggest that the major sources of APM were an electricity plant, road dust, industrial emissions and marine vessels.

Environmental analysis of polar herbicides in complex organic-rich matrices by high performance liquid chromatography atmospheric pressure ionization mass spectrometry (HPLC-API-MS)

A comprehensive forensic investigation of sensitive ecosystems in the Everglades Area is presented. Assessing the background levels of contamination in these ecosystems represents a vital resource to build up forensic evidence required to enforce future environmental crimes within the studied areas. This investigation presents the development and validation of a fractionation and isolation method for two families of herbicides commonly applied in the vicinity of the study area, including phenoxy acids like 2,4-D, MCPA, and silvex; as well as the most common triazine-based herbicides like atrazine, prometyne, simazine and related metabolites like DIA and DEA. Accelerated solvent extraction (ASE) and solid phase extraction (SPE) were used to isolate the analytes from abiotic matrices containing large amounts of organic material. Atmospheric-pressure ionization (API) with electrospray ionization in negative mode (ESP-), and Chemical Ionization in the positive mode (APCI+) were used to perform the characterization of the herbicides of interest.

What are the effects of the 6 +1 Writing Traits on the Attitudes and Writing Skills of Fifth Grade ELLs?

In the Bahamas, ELLs consist mainly of Haitian descent students. Unfortunately, this demographic of students continuously score below their Bahamian counterparts in Creative Writing. This research examined the affects the 6 + 1 Writing Traits assessment had on the attitudes and writing abilities of fifteen, fifth grade, Haitian descent students.