Tastes elicit innate behaviors critical for directing animals to ingest nutritious substances and reject toxic compounds, but the neural basis of these behaviors is not understood. Here, we use a ...neural silencing screen to identify neurons required for a simple Drosophila taste behavior and characterize a neural population that controls a specific subprogram of this behavior. By silencing and activating subsets of the defined cell population, we identify the neurons involved in the taste behavior as a pair of motor neurons located in the subesophageal ganglion (SOG). The motor neurons are activated by sugar stimulation of gustatory neurons and inhibited by bitter compounds; however, experiments utilizing split-GFP detect no direct connections between the motor neurons and primary sensory neurons, indicating that further study will be necessary to elucidate the circuitry bridging these populations. Combined, these results provide a general strategy and a valuable starting point for future taste circuit analysis.
Salt taste, the taste of sodium chloride (NaCl), is mechanistically one of the most complex and puzzling among basic tastes. Sodium has essential functions in the body but causes harm in excess. ...Thus, animals use salt taste to ingest the right amount of salt, which fluctuates by physiological needs: typically, attraction to low salt concentrations and rejection of high salt. This concentration-valence relationship is universally observed in terrestrial animals, and research has revealed complex peripheral codes for NaCl involving multiple taste pathways of opposing valence. Sodium-dependent and -independent pathways mediate attraction and aversion to NaCl, respectively. Gustatory sensors and cells that transduce NaCl have been uncovered, along with downstream signal transduction and neurotransmission mechanisms. However, much remains unknown. This article reviews classical and recent advances in our understanding of the molecular and cellular mechanisms underlying salt taste in mammals and insects and discusses perspectives on human salt taste.
Medicine and the Humanities Gordon, Michael
Canadian journal of bioethics,
06/2023, Volume:
6, Issue:
2
Journal Article
Peer reviewed
Open access
In the earliest writing of stories, physicians and illnesses often played an important role. Some of the renowned scholars in the Jewish tradition, like Moses Maimonides was a philosopher, a prolific ...writer, and a physician. A few of the world-famous authors include: François Rabelais (1483-1553), Anton Chekhov (1860-1904), Arthur Conan Doyle (1859-1930), Oliver Sacks (1933-2015) and the contemporary Abraham Verghese (1955-), to name just a few. The connection between medicine and the humanities appears to have diminished in some domains due partially to the focus on the scientific advances in medicine and the diminished focus on the humanities, especially in higher education. This I suggest, is a problem for medicine.
Kevorkian’s Legacy Gordon, Michael
Canadian journal of bioethics,
06/2023, Volume:
6, Issue:
2
Journal Article
Peer reviewed
Open access
This history of the modern introduction of assisted suicide in North America follow a tortuous course, with complete rejection of the idea, to implementation in many of its jurisdictions. North ...America was not a leader in this approach to end-of-life care, with the Netherlands and Belgium playing that role. Tracing the path from a felonious and ethically anathematic place in North American society it was resurrected into a legally and ethically acceptable practice over a period of two decades. The historical course of PAS (Physician Assisted Suicide) and MAID (Medical Assistance in Dying) in many ways mimicked the evolution of other major changes in our view of the world, and like assisted suicide, experienced almost universal rejection and ultimately the embrace of those people and institutions that initially rejected the ideas first expressed by thoughtful and heroic persons. Galileo Galilei was one of the icons of science and discovery: he was almost burned at the stake during the Inquisition only to be “resurrected” to his place in the pantheon of great thinkers – but it took almost four hundred years to reach that pinnacle. We must be very careful how we interpret new ideas and thoughts about the process we apply and the consequences if we reject them.
The Blessings of Books Gordon, Michael
Canadian journal of bioethics,
06/2023, Volume:
6, Issue:
1
Journal Article
Peer reviewed
Open access
The attack on the written word is not new. It has happened many times through history, especially in modern times as the availability of books has grown so rapidly. It is most often in authoritarian ...regimes that books are deemed a potential threat, and the elimination of this threat a means to maintain control of a potentially rebellious population. Probably the most heinous of book banning and burnings occurred during Nazi rule, prior to and during the Second World War. To witness, recently, in the United States the ugly head book banning and their removal from libraries is a sad commentary on the state of some senior politicians, including Governors and Judicial leaders. Fortunately, there is vigorous opposition to these efforts and notable successes in the quest for universal access to the world of books.
Most of us would agree with the almost trite saying that “life is a journey”. Of course it is, unless it ends tragically at birth, and even then it is a very short journey. All of us can describe how ...we got from one stage in life to another, whether personal, family, education or career. Many journeys seem to be in an almost straight line while others meander from one place to another, changing direction and alternating goals, sometimes zigging back and forth. I have had many wonderful journeys in my life; the choice to change career aspirations from engineering to medicine, the choice the study in medicine in Scotland, the choice to focus on geriatrics and then the choice to branch out into medical ethics to add more depth to clinical medicine. The early undergraduate study of philosophy planted the seed that eventually grew into my completing a Master’s in Medical Ethics; and then expanding my teaching and practice to include palliative care and end of life-decision-making, to most recently participating in the assessment of those requesting medical assistance in dying (MAID in Canada).
Metals that are active catalysts for methane (Ni, Pt, Pd), when dissolved in inactive low–melting temperature metals (In, Ga, Sn, Pb), produce stable molten metal alloy catalysts for pyrolysis of ...methane into hydrogen and carbon. All solid catalysts previously used for this reaction have been deactivated by carbon deposition. In the molten alloy system, the insoluble carbon floats to the surface where it can be skimmed off. A 27% Ni–73% Bi alloy achieved 95% methane conversion at 1065°C in a 1.1-meter bubble column and produced pure hydrogen without CO₂ or other by-products. Calculations show that the active metals in the molten alloys are atomically dispersed and negatively charged. There is a correlation between the amount of charge on the atoms and their catalytic activity.
UK constitution after Brexit - Status of referendums - Use and reception of referendums in the UK - Absence of definitive constitutional framework - Complex legal nature of 'advisory' and 'binding' ...referendums - Deeper constitutional impact on concepts in the political constitution - Regular and irregular authority - Parliamentary and popular sovereignty - Representative and direct democracy - Possibility of reform - A potential UK Referendums Act - Difficulties with an overarching statutory framework - Limitations of continued constitutional accommodation of referendums.
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