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For a long time therapeutic agents that interact with opioid receptors have been used in antidiarrheal therapy. The action of the opioid active substances on motility and transit have already been characterized; however, their effects on myenteric reflexes and their possible luminal action have not yet been investigated. Loperamide, fedotozine and β-casomorphin-4, as well as the casomorphin-analogue β-CM-4027, are, or have been, suggested as therapeutic agents and were studied in the isolated rat ileum for their effect on the ascending reflex pathway. β-CM-4027 > fedotozine > loperamide > β-casomorphin-4 caused a concentration-dependent inhibition of the ascending contractile reflex response with an IC50of 1.4×10–7M, 1.5×10–6M, 4.1×10–6M and 4.5×10–6M respectively. At the same time as the oral contractile reflex response was inhibited, all four opioid agonists (CM-4027 > β-casomorphin-4 > fedotozine > loperamide) increased the latency of the reflex response. Both effects were blocked by naloxone, indicating the involvement of opioid receptors. These results demonstrate that opioid-active drugs and substances modify the peristaltic reflex by reducing the efficacy of the reflex response and modulating the timing of the reflex pathway. In a second series of experiments, luminal application of opioid-active drugs was compared with serosal application. β-casomorphine-4 caused a concentration-dependent inhibition of the oral reflex response with an IC50of 3×10–3M which was 750 times higher than after serosal application. In contrast, a stable and highly selective kappa opioid agonist (U-50,488), which caused potent inhibition upon serosal application (IC50: 2.3×10–7M), showed no inhibitory effect after luminal application up to a concentration of 10–2M. Thus casomorphins could have a local effect on the gut wall with no need for systemic absorption. This might be used for a possible therapeutic application.

The energy and time distributions of the decay X-rays of excited, metastable, molecular (dµHe)*-resonances were measured. The comparison of the observed energy spectra with calculated ones suggests that decay from the rotational state J= 1 dominates at the investigated conditions. The muon transfer rates from ground state deuterium to the helium isotopes 3He and 4He at low temperatures were determined from the time distributions of these spectra. Additionally, the temperature dependence of the muon transfer rate was clearly established in deuterium / 4He mixtures.

The transfer reaction of negative muons from muonic protium to 3and 4in binary and triple gas mixtures was studied. In the binary mixtures the transfer rates to the two helium isotopes were determined from the time distribution of the 7-keV X-rays of the intermediate muonic molecule (pµHe)*. The experimental transfer rate to 4is in good agreement with theoretical predictions, whereas the rate to 3is a factor 2 to 3 smaller than the predicted ones. Radiative branching ratios of the (pµHe)8 molecular decay were obtained. Muon transfer from excited states of muonic protium gives the main contribution to the total intensity of the µHe Lyman series in the binary mixtures. Values of q1sHeare determined.

Abstract: Muon transfer from hydrogen isotopes to helium is of importance in muon-catalyzed fusion and serves as a unique tool for the direct observation of the mesomolecular ion (pµHe)*. During two data-taking runs in 1994 and 1995 at PSI, measurements of the transfer from protium to helium were carried out using CCD's and Ge-diodes as independent X-ray detectors to obtain information on the time distribution and intensity of the 7 keV decay X-ray of the mesomolecular ion. Dual1H2 +4 He and triple1H2 + Ne +3,4He gas mixtures at low temperatures were investigated to extract transfer rates. Protium of high purity was available. For the first time a transfer rate from muonic protium to3He was measured. A general survey of our measurements and preliminary analysis is presented.

Abstract: Preliminary results are reported for an experiment at TRIUMF where a time-of-flight technique was tested for measuring the energy dependence of the rate for muon-catalyzed dt fusion. Muonic tritium atoms were created following transfer of negative muons from muonic protium in a layer of solid hydrogen (protium) containing a small fraction of tritium. The atoms escaped from the solid layer via the Ramsauer-Townsend mechanism, traversed a drift region of 18 mm, and then struck an adjacent layer of deuterium, where the muonic atom could form a molecular system. The time of detection of a fusion product (neutron or alpha) following muon arrival is dependent upon the energy of the muonic tritium atom as it traverses the drift region. By comparison of the time distribution of fusion events with a prediction based on the theoretical energy dependence of the rate, the strength of resonant formation can in principle be determined. The results extracted so far are discussed and the limitations of the method are examined.

Abstract: Muon transfer from the ground state of muonic deuterium to a helium atom proceeds mainly via the formation of a muonic molecule in an excited state. A large number of decay X rays (sim 6.8 keV) from these (dµHe)* molecules were observed for the4He as well as for the3He case. The time distributions of these X rays allow the determination of the ground state transfer rate. The simultaneous employment of Ge/Si-detectors and CCDs for the same target conditions allows the determination of the branching ratio of radiative to nonradiative decay for the first time.

Abstract: Several experiments performed by our group in recent years have put into evidence the complex structure of the time distributions of the muonic X-rays following transfer from muonic hydrogen isotopes to heavier elements. Simulations have shown that a substantial fraction of the µp atoms in the ground state have epithermal energies. Therefore, an energy dependence of the transfer rate seems a reasonable assumption for the explanation of the complex time structure.

Abstract: To investigate the energy dependence of muon transfer to oxygen, we performed measurements in gaseous mixtures of hydrogen and oxygen. The time distributions of the muonic oxygen X-rays showed the same structure as the one observed earlier in H2+SO2 mixtures. In the delayed part of these distributions, one can distinguish a short-time and a long-time component. From the latter, we deduced the transfer rates from thermalized muonic protium, respectively deuterium, to oxygen. The short-time component can be interpreted as being due to muon transfer from epithermal muonic hydrogen atoms. The time parameters are characteristic for the deceleration process as well as for energy-dependent transfer rates. With results of recent research on the formation and the thermalization of muonic hydrogen, we performed Monte Carlo simulations in order to test the hypothesis of an energy-dependent transfer rate.

Abstract: Negative muons were trapped in gaseous mixtures of hydrogen and oxygen. The time distributions of the muonic oxygen X-rays showed a clear deviation from a single exponential structure. From these time distributions we evaluated the transfer rate from thermalized muonic hydrogen atoms to oxygen. In order to test the hypothesis of an energy-dependent transfer rate to oxygen we performed Monte Carlo simulations of the thermalization and the transfer process. We report on the present status of our investigations.

The yields of muonic x rays of the Lyman series of nitrogen, neon and argon have been analysed to determine capture ratios A(Z1,Z2) in about thirty gaseous mixtures under different experimental conditions. In addition, capture ratios A(Z,H) have been determined in hydrogen mixtures by taking into account transfer processes from muonic hydrogen to elements Z. The influence of the spectral flux density of the muons on capture ratios has been analysed. Our per-atom ratios form a coherent set and confirm the value A(Ar,Ne) = 1. 262(10).

Discusses `sick-building syndrome,' caused in people who work in buildings where air is circulated through a central heating and air-conditioning system and windows don't open. Symptoms; Causes; Germs; Making buildings better.

In 1977 the United States Army presented a lengthy, supposedly comprehensive report on its biological warfare (BW) testing program of the 1950s and 1960s to a Senate subcommittee. Although the report did not indicate the scale or number of field tests, it did show which disease-causing organisms were used, and when they were—forty-four projects in all. These revelations cast a long shadow of doubt on the Army's claims about its current research program. Technically, this nation is out of the BW business.

Steven Newmaster had been cleared, but fresh inquiry concludes he likely made up data.

The high-profile paper contains manipulated images, senior author acknowledges.

Inspectors faulted analyses of clinical trial samples by Hoau-Yan Wang for drug developer Cassava Sciences.

Whistleblowers and former lab members suggest a star neuroscientist routinely manipulated data, compromising a planned NIH stroke trial and key Alzheimer's research.

Co-developer of biotech's drug couldn't supply original data.

Amyloid-clearing antibody lecanemab faces key FDA hearing in June.

Antibody slows cognitive decline, but deaths, brain bleeds, and swelling mar results.

Matthew Schrag confronts a mentor after their joint work is flagged on the PubPeer website.

A neuroscience image sleuth finds signs of fabrication in scores of Alzheimer's articles, threatening a reigning theory of the disease.

Report sees "insufficient evidence" of misconduct.

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