Palladium-Catalyzed Asymmetric Conjugate Addition of Arylboronic Acids to Five-, Six-, and Seven-Membered β-Substituted Cyclic Enones: Enantioselective Construction of All-Carbon Quaternary Stereocenters

The first enantioselective Pd-catalyzed construction of all-carbon quaternary stereocenters via 1,4-addition of arylboronic acids to β-substituted cyclic enones is reported. Reaction of a wide range of arylboronic acids and cyclic enones using a catalyst prepared from Pd(OCOCF_3)_2 and a chiral pyridinooxazoline ligand yields enantioenriched products bearing benzylic stereocenters. Notably, this transformation is tolerant to air and moisture, providing a practical and operationally simple method of synthesizing enantioenriched all-carbon quaternary stereocenters

Key Administrative Decisions in the History of the Seventh-day Adventist Education in Bermuda

Problem. In 1993, during the celebration of fifty years of continuous Christian education in Bermuda, it became strikingly evident that the Seventh-day Adventist Church had no single literary, historical compilation of SDA education in the country. This research can help to fill this information void. Method. Seven key administrative decisions have been identified as being of paramount importance in influencing the manner in which SDA education has developed in Bermuda: (1) the initial decision to found an SDA school, (2) the relocation of the school to the Sandringham property, (3) the expansion from eight grades to twelve, (4) the choices made between an American and a British curriculum, (5) the decisions concerning the best use of limited land, (6) the selection of a financial plan for operating the school, and (7) decision-making processes involved in selecting successive principals. This research covers the period from the year 1943 through 1997, the period of continuous SDA education in Bermuda. The scope of this research excludes any schools which may have existed before 1943. The intent of this research is not to provide a complete historical record of the period, but to examine certain key administrative decisions and their effects on the development of SDA education in Bermuda. Results. These key administrative decisions have been important for the evangelistic thrust of the SDA Church in Bermuda and for training workers for both the Church and the broader community. They have enabled Bermudian students to have the convenience and financial benefits of acquiring more of their education at home, have made the teaching process easier for the mostly American trained staff, and have facilitated the transfer of students\u27 academic credits between Bermuda Institute and American schools. These decisions have raised the quality of education and accommodated a growing student population by constructing buildings on the limited open land spaces. They have enabled the Bermuda Conference to operate the school for the most part without recurring deficits but have contributed to a rapid turnover of principals. Conclusions. The SDA school in Bermuda has grown from humble beginnings to a respected and competitive institution due largely to certain key decisions made by successive administrators and administrating committees

Polydimethylsiloxane Substrates for passive UHFRFID Sensors

PDMS has previously shown to be a suitable substrate for UHF-RFID strain sensor tags due to their elastomer characteristics. However, PDMS has further properties such as polymer swelling which could be utilized in gas sensing. Macroporous PDMS sponges have been proposed as suitable substrates for passive gas sensors. Porous sponges were fabricated using sugar templates and their absorption capacity was investigated along with standard PDMS elastomers. Possible applications could include food package and air quality monitoring

Skin-Mounted RFID Sensing Tattoos for Assistive Technologies

UHF RFID technology is presented that can facilitate new passive assistive technologies. Tongue control for human computer interfaces is first discussed where a tag is attached to the hard palate of the mouth and the tag turn-on power is observed to vary in response to tongue proximity. Secondly, a stretchable tag is fabricated from Lycra fabric that contains conducting silver fibres. The application of strain to the elastic tag again causes the required power at the reader to activate the tag to vary in proportion. This elastic tag is proposed as a temporary skin mounted strain gauge that could detect muscle twitch in the face or neck of an otherwise physically incapacitated person. Either design might be applied to the steering function of a powered wheelchair, or to facilitate the control of a computer mouse. Better than 3dB isolation is achieved in the tongue switching case and approximately 0.25dBm per percentage stretch is observed for the strain gauge

The Economic Value of Sharks

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A Companion of the Sunfish

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The Color Changes in Lizards

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