Dark State Optical Lattice with a Subwavelength Spatial Structure.

We report on the experimental realization of a conservative optical lattice for cold atoms with a subwavelength spatial structure. The potential is based on the nonlinear optical response of three-level atoms in laser-dressed dark states, which is not constrained by the diffraction limit of the light generating the potential. The lattice consists of a one-dimensional array of ultranarrow barriers with widths less than 10 nm, well below the wavelength of the lattice light, physically realizing a Kronig-Penney potential. We study the band structure and dissipation of this lattice and find good agreement with theoretical predictions. Even on resonance, the observed lifetimes of atoms trapped in the lattice are as long as 44 ms, nearly 10^{5} times the excited state lifetime, and could be further improved with more laser intensity. The potential is readily generalizable to higher dimensions and different geometries, allowing, for example, nearly perfect box traps, narrow tunnel junctions for atomtronics applications, and dynamically generated lattices with subwavelength spacings.

Nanoscale "Dark State" Optical Potentials for Cold Atoms.

We discuss the generation of subwavelength optical barriers on the scale of tens of nanometers, as conservative optical potentials for cold atoms. These arise from nonadiabatic corrections to Born-Oppenheimer potentials from dressed "dark states" in atomic Λ configurations. We illustrate the concepts with a double layer potential for atoms obtained from inserting an optical subwavelength barrier into a well generated by an off-resonant optical lattice, and discuss bound states of pairs of atoms interacting via magnetic dipolar interactions. The subwavelength optical barriers represent an optical "Kronig-Penney" potential. We present a detailed study of the band structure in optical Kronig-Penney potentials, including decoherence from spontaneous emission and atom loss to open "bright" channels.

Differentiation between used motor oils on the basis of their IR spectra with application of the correlation method.

Two brands of motor oils (Elf and Castrol) that had been used for various periods of time were examined. The aim was to differentiate these samples (of varying degree of use) on the basis of their infrared spectra, for criminalistic purposes. The correlation method was used. It was found that the FTIR method is capable of providing sufficiently detailed information if some specific fragments of spectra are examined. Hence, it can be concluded that the investigation procedure proposed is adequate.

[Gallbladder carcinoma--results of treatment]. / Rak pecherzyka zólciowego--wyniki leczenia.

One-hundred patients treated for gallbladder carcinoma in the years 1970-1986 are described. They accounted for 2.63% of all patients treated surgically for diseases of the gallbladder and bile ducts. Coexistence of carcinoma and cholelithiasis was found in 76% of cases. In 64 cases only exploratory laparotomy was done and biopsy was done for histological examination, since the progression of the tumour precluded any radical operation. In 15 cases cholecystectomy was done and in the remaining 21 patients palliative procedures were done. In the perioperative period 17 patients died. Information on the length of survival time was obtained in 43 cases. It was longest in cases in which the degree of progression of the tumour was classified into stages I and II after Nevin. Six patients are alive 7 months to 8 years after the operation. The authors think that the methods for improvement of the results of surgical treatment should be sought in prevention of this carcinoma that is early surgical treatment of cholelithiasis.

The sensitivity of the respiratory center and some circulatory and subjective responses after nalorphine and naloxone injections.

In five volunteers the sensitivity of the respiratory centre to carbon dioxide after naloxone and nalorphine injections was studied using "double blind" method and increments of doses. Alterations in the respiratory centre sensitivity were reflected by changes in respiratory minute volume, which was measured before and after drug injections, as well as after carbon dioxide stimulation. Comparison of results and their statistical verification showed that nalorphine alone causes respiratory depression and carbon dioxide stimulation is, beside the weak initial action, almost ineffective. Naloxone causes very small, if at all, respiratory depression and the respiratory centre answers efficiently to carbon dioxide stimulation.