Solid ultra-cold neutron detectors consisting of a neutron converter layer and a silicon pin-diode were tested at Institute Laue Langevin. Two kinds of converter, LiF and LiOH, were used, and their critical velocities covered the range from 0.8 to 5.0m/s by adjusting the isotopic fraction of 6Li in Li. All tested detectors measured the UCN below their critical velocities down to 1.5m/s without a clear cutoff feature at their critical velocities. It is an abnormal absorption of UCN. It was also observed that the detector efficiencies of all tested detectors approach together in the UCN region, 4–6m/s, in spite of the variety of critical velocity and thickness of converters.

The first ultracold-neutron (UCN) production in superfluid helium placed in a spallation neutron source is carried out. A UCN density of 0.7 UCN/cm(3), which can be used in experiments, is achieved for a proton-beam power of 78 W and a He-II temperature of 1.2 K. The present new UCN source is not limited by Liouville's theorem and extraction losses, which were serious problems in the previous sources. The present source has the possibility of extremely high-density UCN production compared with previous UCN sources.

Although the target cells for the bone marrow (BM) and peripheral blood (PB) micronucleus tests are the same, erythroblasts, the PB method offers important advantages over the BM method. We propose a protocol for the shortterm peripheral blood micronucleus test. This assay is intended primarily for the identification of a wide variety of chemical clastogens and spindle poisons, and secondarily for risk assessment. The recommended experiment size, seemingly small, has adequate detection power. Experimental results obtained from Collaborative Study Group for the Micronucleus Test (CSGMT) studies and data collected from a survey of the literature provided the basis of the proposed protocol. Our protocol, designed for mice, includes the following features. (i) The maximum tolerated dose (MTD) is determined experimentally with a small number of animals treated i.p. or per os (or by other routes, if called for) in a dose-finding test, which can be conducted simultaneously with tests for finding both number of treatments and optimal sampling time. (ii) At least three groups of five mice (at least four effective animals per group), males or females, are given i.p, or per os doses of, for example, the MTD, 1/2 MTD and 1/4 MTD once, twice or more, 24 h apart. (iii) Peripheral blood samples are taken before treatment (the 0 time control) and twice at 48 and 72 h for a single treatment, once between 24 and 36 h after the second treatment for double treatments, or once 24 h after the final treatment for multiple dosing. Or, if an optimal sample time is established in a preliminary test, samples are taken at that time, (iv) Samples are stained with acridine orange, and 2000 immature erythrocytes per animal are examined. (v) The combined data of 0 time samples are the negative control. When statistical analysis shows that the negative control is out of the historical control range or experimental results are equivocal, a repeat test is needed.

The Tohoku Bubble Chamber has the distinctions of being the last built, and of having carried out the last bubble chamber exposure in the western world (1990). It was designed as a large volume freon chamber with high resolution holography throughout, and carried out two successful neutrino exposures in 1985 and 1987. We present here a brief description on this chamber.

Collocated observations from microwave radiometer and wind profiler are used in a pilot study during the monsoon period to derive information on the thermodynamics and winds and association with rainfall characteristics. These instruments were operated throughout the monsoon season of 2015. Continuous vertical profiles of winds, temperature and humidity show significant promise for understanding the low-level jet, its periodicity and its association with moisture transport, clouds and precipitation embedded within the monsoon large-scale convection. Observations showed mutually beneficial in explaining variability that are part of the low frequency oscillations and the diurnal variability during monsoon. These observations highlight the importance of locally driven convective systems, in the presence of weak moisture transport over the area. The episodic moisture convergence showed a periodicity of 9 days which matches with the subsequent convection and precipitation and thermodynamic regimes. Inferences from the diurnal cycle of moisture transport and the convective activity, relationship with the low-level jet characteristics and thermodynamics are also illustrated.

The study of muon properties and decays played a crucial role in the early years of particle physics and contributed over decades to build and consolidate the Standard Model. At present, searches for muon decays beyond the Standard Model are performed by exploiting intense beams of muons, and plans exist to upgrade the present facilities or build new ones, which would open new prospects for the quest of new physics in this sector. In this paper I review the present status of the search for muon decays beyond the Standard Model, with a special attention to the most conventional muon lepton flavor violation experiments, but also considering more exotic scenarios and future outlooks.

The effects of a mitotic arrestant, IKP‐104, which has an antitumor activity, on the in vitro., polymerization and depolymerization of rat brain microtubules were investigated. IKP‐104 inhibited microtubule polymerization at concentrations greater than 0.71 × 10‐6M.,a nd its IC50 value was determined to be 1.31 × 10‐6 M by probit analysis. Fifty‐two percent of pre‐polymerized microtubules depolymerized at 1.31 × 10‐6M IKP‐104. Electron micrographs of microtubules taken immediately after treatment with 1 × 10‐3M IKP‐104 revealed a fraying of microtubule ends into elongated coil‐like filaments, which were composed of 2 or 3 protofilaments. When microtubule protein treated with 1 × 10‐3M IKP‐104 was cleaved by trypsin, fragments of 41,36, 34, 23,21,19 and 16 kilodaltons (kDa) derived from a‐tubulin were produced. In particular, the 19, 23 and 34 kDa fragments were characteristically observed in the trypsin cleavage of microtubules treated with IKP‐104, and these fragments were not observed with untreated microtubules. The effects of IKP‐104 on microtubule protein mentioned above were mostly similar to those of vinblastine (VLB) and we suggest that IKP‐104 bound to the site or sites near “VLB‐binding site or sites” of α‐tubulin subunit, resulting in induction of conformational changes.

We have used the Fermilab 30-in. bubble-chamber-hybrid spectrometer to study neutral-strange-particle production in the interactions of 200-GeV/c protons and pi+ and K+ mesons with nuclei of gold, silver, and magnesium. Average multiplicities and inclusive cross sections for K0 and LAMBDA are measured, and a power law is found to give a good description of their A dependence. The exponent characterizing the A dependence is consistent with being the same for K0 and LAMBDA-production, and also the same for proton and pi+ beams. Average K0 and LAMBDA-multiplicities, as well as their ratio, have been measured as functions of the numbers of projectile collisions-nu(p) and secondary collisions-nu(s), in the nucleus, and indicate that rescattering contributes significantly to enhancement of LAMBDA-production but not to K0 production. The properties of events with multiple K0's or LAMBDA's also corroborate this conclusion. K0 rapidities are in the central region and decrease gently with increasing nu(p), while LAMBDA-rapidities are in the target-fragmentation region and are independent of nu(p). K0 and LAMBDA-multiplicities increase with the rapidity loss of the projectile, but their rapidities do not.

Structure-activity relationships and in vitro evaluation of eye irritation potential of salicylates in rabbits were studied. The primary eye irritation potential of ten salicylates was evaluated according to Draize method. The effects of chemicals on model protein and lipid were investigated in vitro. The effects of chemicals on the protein could be detected by the production of aggregates of human serum gamma-globulin (HSG) and a good correlation was obtained between the ability of salicylates to produce aggregation of HSG and the potential of corneal irritation. The effects on the lipid could be detected by the adhesion potential of chemicals on lipid membrane and a linear correlation was not obtained between the adhesionary effects of salicylates on lipid membrane and the potential eye irritation. The corneal irritation and protein aggregation potential of salicylates were correlated with the acid dissociation constant more closely than octanol/water partition coefficient. The destruction of alpha-helix of proteins in corneal surface by salicylates were observed from the nondestructive structural analysis of corneal surface by Fourier Transform (FT)-IR spectroscopy. These results suggest that eye irritation caused by salicylates are mainly the results of denaturation of proteins in ocular tissue and that the effects on protein depend on the dissociation potential of molecules.

The effects of IKP-104, a 4(1-H)-pyridinone derivative, on the mitotic profile and cytoskeletal microtubule dynamics of cultured B16 melanoma cells were examined in order to investigate the mechanism of its antitumor activity. The exposure to IKP-104 caused accumulation of cells in abnormal metaphase with chromosomes scattered within the cytoplasm and induced polyploid and multinucleate cells as detected by differential staining microscopy with brilliant blue R and safranin O. An immunofluorescence study with monoclonal anti-alpha-tubulin antibody revealed that IKP-104 diminished cytoskeletal microtubules of both interphase and mitotic cells, resulting in induction of a few fragments resembling "microtubular bundles" induced by vinblastine (VLB). These results indicated that IKP-104 arrests cells in the mitotic phase by inhibition of polymerization and induction of depolymerization of cytoskeletal microtubules, similarly to VLB.

Rat red blood cells were used as an in vitro method to evaluate the eye irritation potential of chemicals in rabbits. The results using 116 chemicals of various categories including medicines, pesticides, detergents and solvents were analyzed for the prediction of possibility of eye irritation potentials. Eye irritation of chemicals was examined according to Draize method and chemicals were classified into three categories, (1) non or mild irritants, (2) moderate or severe irritants and (3) strong or corrosive irritants, based on the recovery of damages. The in vitro method consisted of two methods detecting the effects of chemicals mainly on protein and lipid in the membrane, which were evaluated by the induction of methemoglobin and hemolysis, respectively. Non- or mild irritants induced neither methemoglobin formation nor hemolysis. Most of moderate or severe irritants induced hemolysis, however, the potentials were low. Strong or corrosive irritants had high potentials for the induction of methemoglobin. The multivariate estimation by the above two in vitro data sets were 77.6% predictive of the in vivo classification.

A quantitative structure-activity relationship (QSAR) approach has been applied to the analysis of the relation between the structural features of chemicals and the primary eye irritation in rabbits. One hundred thirty one heterogeneous chemicals including medicals, pesticides, detergents and organic solvents were used in this study. The eye irritation ratings were made in three classes on the basis of the recovery time of corneal and conjunctival damages. Thirty six descriptors were used to describe the molecules. To correlate eye irritation ratings with the descriptors, a QSAR model was formulated by the adaptive least-squares method. A three-class discrimination was made as follows; class I included 23 chemicals which induced the damages recovering within 24 hr, class II included 64 chemicals which induced the damages persisting for more than 24 hr but recovering within 21 days, class III included 44 chemicals which induced the damages not recovering within 21 days. The discriminant function included 18 descriptors. The accuracy in classifying the chemicals was 86.3% in the recognition and 74.0% in the leave-one-out prediction. These results suggest that QSAR analysis is valuable to predict the primary eye irritation of chemicals.

Antitumor activities of IKP‐104, a 4(1 H )‐pyrizinone derivative, were investigated with cultured tumor cell lines and implanted tumors in mice. IKP‐104 inhibited the growth of cultured murine tumor cell lines (L1210 leukemia, Lewis lung carcinoma and B16 melanoma) and human tumor cell lines (K562 leukemia and HeLa cervical carcinoma). It also had antitumor effects on implanted murine ascitic tumors (L1210 leukemia and sarcoma 180) and a murine solid tumor (Lewis lung carcinoma). IKP‐104 could be classified as a phase‐dependent cytostatic drug based on the mode of growth inhibition of cultured B16 melanoma cells compared with those of several other antitumor agents. The effect of IKP‐104 on the cell cycle traverse of cultured B16 melanoma cells was estimated by morphological and flow cytometric analyses. Cells accumulated in the mitotic phase, and abortive mitosis or polyploidy or multinucleation was induced from 6 h after exposure to IKP‐104. Based on these results, IKP‐104 is expected to be useful for the treatment of tumors, and its mode of action seemed to be similar to that of metaphase arrestants such as colchicine or vinca alkaloids.

We have used the Fermilab 30-in. bubble chamber--hybrid spectrometer to study the rapidities of ``produced particles'' in the interactions of 200-GeV/c protons and ${\ensuremath{\pi}}^{+}$ and ${K}^{+}$ mesons with nuclei of gold, silver, and magnesium. The average rapidity decreases linearly with the number of projectile collisions ${\ensuremath{\nu}}_{p}$ (up to ${\ensuremath{\nu}}_{p}$=5) with no A dependence and little beam dependence. The ratio R of normalized rapidity distributions for hadron-nucleus to hadron-proton interactions shows a plateau in the central region, and becomes much larger in the target region. However, the increase is significantly less than has been reported in previous experiments. As a function of ${\ensuremath{\nu}}_{p}$, the ratio R rises linearly in the target region, more gently in the central region, and decreases slowly in the projectile region, in all cases with no A dependence. Some discrepancies with a previous experiment are observed in the central region. Long-range rapidity correlations are observed in hadron-nucleus events, but not in hadron-proton events. For the former, it is shown that the correlations exist only for those events with multiple projectile collisions, as expected in the multichain dual parton model.

We examine the negative $3\ensuremath{\pi}$ final state produced in association with ${\ensuremath{\Delta}}^{++}(1232)$ in the reaction $\ensuremath{\gamma}p\ensuremath{\rightarrow}{\ensuremath{\Delta}}^{++}{\ensuremath{\pi}}^{+}{\ensuremath{\pi}}^{\ensuremath{-}}{\ensuremath{\pi}}^{\ensuremath{-}}$ at an incident photon energy of 19.3 GeV. The most prominent enhancement in the $3\ensuremath{\pi}$ spectrum occurs at a mass and with a width consistent with the parameters of the ${a}_{2}(1320)$. This identification is confirmed by the various angular distributions. The ${a}_{2}$ production cross section, corrected for efficiencies and alternate ${a}_{2}$ decay modes, is 0.45\ifmmode\pm\else\textpm\fi{}0.05 \ensuremath{\mu}b.

A high resolution holographic freon bubble chamber has been constructed for a high energy neutrino experiment at Fermilab. The chamber has a volume of 1150 l filled with a heavy liquid (freon) and has high resolution holographic optics. A muon detector system has been installed to measure high energy muons scattered from the neutrino interactions. Some systematic studies have been done to optimize bubble chamber operation with holographic photography. Results of these studies are presented along with a description of the hybrid bubble chamber system.