2,424 research outputs found
Marijuana Business Attorneys and the Professional Deference Standard
Imagine that you practice as an attorney in the State of Arkansas. A client solicits your advice about opening a marijuana dispensary or cultivation center. The client might want you to assist him in filing a dispensary application with the State. On the other hand, she might want you to negotiate a commercial lease or to provide services to ensure compliance with municipal zoning laws. Although Arkansas voters approved a constitutional amendment permitting medical marijuana sales, you provide a clear warning to your client: possessing, manufacturing, selling, and distributing marijuana remains a federal crime. After these precautions, however, you proceed to business as usual, providing a routine legal service just as you would for any other client
The high frequency flexural ultrasonic transducer for transmitting and receiving ultrasound in air
Flexural ultrasonic transducers are robust and low cost sensors that are typically used in industry for distance ranging, proximity sensing and flow measurement. The operating frequencies of currently available commercial flexural ultrasonic transducers are usually below 50 kHz. Higher operating frequencies would be particularly beneficial for measurement accuracy and detection sensitivity. In this paper, design principles of High Frequency Flexural Ultrasonic Transducers (HiFFUTs), guided by the classical plate theory and finite element analysis, are reported. The results show that the diameter of the piezoelectric disc element attached to the flexing plate of the HiFFUT has a significant influence on the transducer's resonant frequency, and that an optimal diameter for a HiFFUT transmitter alone is different from that for a pitch-catch ultrasonic system consisting of both a HiFFUT transmitter and a receiver. By adopting an optimal piezoelectric diameter, the HiFFUT pitch-catch system can produce an ultrasonic signal amplitude greater than that of a non-optimised system by an order of magnitude. The performance of a prototype HiFFUT is characterised through electrical impedance analysis, laser Doppler vibrometry, and pressure-field microphone measurement, before the performance of two new HiFFUTs in a pitch-catch configuration is compared with that of commercial transducers. The prototype HiFFUT can operate efficiently at a frequency of 102.1 kHz as either a transmitter or a receiver, with comparable output amplitude, wider bandwidth, and higher directivity than commercially available transducers of similar construction
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Adoption of managerial innovations: effect of adoption rationales on the adoption process
The aim of the research is to explore the complex phenomenon of the adoption of managerial innovations by organisations, with an attempt to identify relationships between various elements of this process. Four case studies were compiled using interview data from selected managers. The data provided a means of subjecting the rationales that Sturdy (2004) posited for the adoption of managerial innovations to empirical inquiry. The study also seeks to explore how the identified rationales may relate to two main characteristics of the subsequent adoption process, namely, the timing of adoption in the life cycle of the innovation and how long the adoption process takes. To our knowledge, this study represents the first empirical exploration of the adoption rationales posited by Sturdy and their subsequent impact on the adoption process. The findings of the study will be of value to academics interested studying the adoption of managerial innovations and also practising managers who must make adoption decisions and manage the adoption process. It is recognised that the study is exploratory in nature and suggestions for further research are proposed
On reduction of differential inclusions and Lyapunov stability
In this paper, locally Lipschitz, regular functions are utilized to identify
and remove infeasible directions from set-valued maps that define differential
inclusions. The resulting reduced set-valued map is point-wise smaller (in the
sense of set containment) than the original set-valued map. The corresponding
reduced differential inclusion, defined by the reduced set-valued map, is
utilized to develop a generalized notion of a derivative for locally Lipschitz
candidate Lyapunov functions in the direction(s) of a set-valued map. The
developed generalized derivative yields less conservative statements of
Lyapunov stability theorems, invariance theorems, invariance-like results, and
Matrosov theorems for differential inclusions. Included illustrative examples
demonstrate the utility of the developed theory
Radiative Hydrodynamic Simulations of HD209458b: Temporal Variability
We present a new approach for simulating the atmospheric dynamics of the
close-in giant planet HD209458b that allows for the decoupling of radiative and
thermal energies, direct stellar heating of the interior, and the solution of
the full 3D Navier Stokes equations. Simulations reveal two distinct
temperature inversions (increasing temperature with decreasing pressure) at the
sub-stellar point due to the combined effects of opacity and dynamical flow
structure and exhibit instabilities leading to changing velocities and
temperatures on the nightside for a range of viscosities. Imposed on the
quasi-static background, temperature variations of up to 15% are seen near the
terminators and the location of the coldest spot is seen to vary by more than
20 degrees, occasionally appearing west of the anti-solar point. Our new
approach introduces four major improvements to our previous methods including
simultaneously solving both the thermal energy and radiative equations in both
the optical and infrared, incorporating updated opacities, including a more
accurate treatment of stellar energy deposition that incorporates the opacity
relevant for higher energy stellar photons, and the addition of explicit
turbulent viscosity.Comment: Accepted for publication in Ap
Maori economic development - Glimpses from statistical sources
This draft book chapter provide an overview of Maori economic development during the past 150 years, drawing on readily available statistical and historical sources. The path of Maori economic development that we have traced through statistical evidence is one of ongoing change and adaptation, as well as one of substantial increase in material standards of living, albeit with periods of significant setback.Maori economic development
Venting in the comparative study of flexural ultrasonic transducers to improve resilience at elevated environmental pressure levels
The classical form of a flexural ultrasonic transducer is a piezoelectric ceramic disc bonded to a circular metallic membrane. This ceramic induces vibration modes of the membrane for the generation and detection of ultrasound. The transducer has been popular for proximity sensing and metrology, particularly for industrial applications at ambient pressures around 1 bar. The classical flexural ultrasonic transducer is not designed for operation at elevated pressures, such as those associated with natural gas transportation or petrochemical processes. It is reliant on a rear seal which forms an internal air cavity, making the transducer susceptible to deformation through pressure imbalance. The application potential of the classical transducer is therefore severely limited. In this study, a venting strategy which balances the pressure between the internal transducer structure and the external environment is studied through experimental methods including electrical impedance analysis and pitch-catch ultrasound measurement. The vented transducer is compared with a commercial equivalent in air towards 90 bar. Venting is shown to be viable for a new generation of low cost and robust industrial ultrasonic transducers, suitable for operation at high environmental pressure levels
Concerted hydrogen atom exchange between three HF molecules
We have investigated the termolecular reaction involving concerted hydrogen exchange between three HF molecules, with particular emphasis on the effects of correlation at the various stationary points along the reaction. Using an extended basis, we have located the geometries of the stable hydrogen-bonded trimer, which is of C(sub 3h) symmetry, and the transition state for hydrogen exchange, which is of D(sub 3h) symmetry. The energies of the exchange reation were then evaluated at the correlated level, using a large atomic natural orbital basis and correlating all valence electrons. Several correlation treatments were used, namely, configration interaction with single and double excitations, coupled-pair functional, and coupled-cluster methods. We are thus able to measure the effect of accounting for size-extensivity. Zero-point corrections to the correlated level energetics were determined using analytic second derivative techniques at the SCF level. Our best calculations, which include the effects of connected triple excitations in the coupled-cluster procedure, indicate that the trimer is bound by 9 +/- 1 kcal/mol relative to three separate monomers, in excellent agreement with previous estimates. The barrier to concerted hydrogen exchange is 15 kcal/mol above the trimer, or only 4.7 kcal/mol above three separated monomers. Thus the barrier to hydrogen exchange between HF molecules via this termolecular process is very low
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The synthesis of prostaglandin analogues
A route was devised which led to the synthesis of 11-deoxyhomoprostacyclin(I), an analogue of prostacyclin (or PGI2) (III). A novel synthetic route to 11-deoxyprostaglandins of the E and F series was also developed.
Natural PGI2 (III) is unstable due to the lability of the enol ether moiety to hydrolysis, but has desirable biological properties, with potential therapeutic applications in the treatment or control of thrombosis. It was hoped that the analogue (I), in which the enol ether moiety has been split up by an extra methylene group, would exhibit similar biological properties. The 11-deoxy analogue(I) was chosen as the initial target since these molecules are easier to synthesise than their 11-hydroxylated counter parts and still exhibit interesting biological properties. The route was devised, however, to be sufficiently flexible so as to allow subsequent synthesis of the 11-hydroxylated analogue(II).
The key step was an organocuprate conjugate addition enolate alkylation reaction. Using various alkylating agents such as allyl bromide or 2-methoxyallyl bromide, gave intermediates which were further functionalised to give the key bicyclic pyran type system. This was then converted by known procedures to the target(I).
An interesting degradative oxidation of one of the intermediates on activated manganese dioxide led to the lactone (IV). This was converted by known procedures to the Corey Lactone an intermediate in the synthesis of ll-deoxy E and F prostaglandins thus constituting a new formal synthesis of these compounds
Doctor of Philosophy
dissertationThe primary cause of chronic myelogenous leukemia (CML) is the presence of the Philadelphia chromosome, resulting in the oncoprotein Bcr-Abl. The constitutive tyrosine kinase activity of Bcr-Abl, localized intracellularly in the cytoplasm, activates numerous oncogenic signaling pathways. Conversely, Bcr-Abl trapped in the cell nucleus induces apoptosis. This work is aimed at turning the oncogenic Bcr-Abl signaling into apoptotic signaling through redirecting Bcr-Abl, found only in the cancerous cells, to the nucleus. First, this work validated that Bcr-Abl could be directed to the nucleus with nuclear localization signals, and that nuclear Bcr-Abl does induce apoptosis. Ectopic expression of a nuclear localized Bcr-Abl construct in CML cells activated apoptotic signaling. Next, this worked focused on the design and isolation of Bcr-Abl binding domains. The first approach was the rational design of the Bcr-Abl coiled-coil domain which led to identification of mutations that could be made to enhance the oligomerization properties with Bcr-Abl. A nuclear translocation assay was then developed for studying protein interactions inside a live cell, and confirmed the modifications to the coiled-coil domain improved the binding to the wild-type coiled-coil domain representative of Bcr-Abl. In addition to the application to translocating Bcr-Abl iv to the nucleus, the improved oligomerization domain (CCmut2) was found to function as an inhibitor of Bcr-Abl. A second generation modification to the Bcr-Abl coiled-coil domain, CCmut3, was found to exhibit even greater binding than CCmut2 and also inhibited Bcr-Abl. As an alternative binding approach we used the intracellular antibody capture (IAC) methodology to isolate single domain antibodies (iDabs). Two Bcr-Abl regions with potential implications in the cytoplasmic retention of Bcr-Abl were targeted in the iDabs screens, the actin binding domain and Dbl homology/Pleckstrin homology domains. These screens produced ABI7, and when co-expressed with Bcr-Abl, caused a redistribution of the normal Bcr-Abl localization pattern. Both CCmut3 and ABI7 were tested for their ability to translocate Bcr-Abl into the nucleus and together were found to efficiently redirect Bcr-Abl to the nucleus. The culmination of this work is an established method to efficiently redirect Bcr-Abl from the cytoplasm into the nucleus where it is known to induce apoptosis
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