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We present a unique matter-wave interferometer whose phase scales with the cube of the time the atom spends in the interferometer. Our scheme is based on a full-loop Stern-Gerlach interferometer incorporating four magnetic field gradient pulses to create a state-dependent force. In contrast to typical atom interferometers that make use of laser light for the splitting and recombination of the wave packets, this realization uses no light and can therefore serve as a high-precision surface probe at very close distances.

Magnetic-film atom chip with 10 µm period lattices of microtraps for quantum information science with Rydberg atoms.

We describe the fabrication and construction of a setup for creating lattices of magnetic microtraps for ultracold atoms on an atom chip. The lattice is defined by lithographic patterning of a permanent magnetic film. Patterned magnetic-film atom chips enable a large variety of trapping geometries over a wide range of length scales. We demonstrate an atom chip with a lattice constant of 10 µm, suitable for experiments in quantum information science employing the interaction between atoms in highly excited Rydberg energy levels. The active trapping region contains lattice regions with square and hexagonal symmetry, with the two regions joined at an interface. A structure of macroscopic wires, cutout of a silver foil, was mounted under the atom chip in order to load ultracold (87)Rb atoms into the microtraps. We demonstrate loading of atoms into the square and hexagonal lattice sections simultaneously and show resolved imaging of individual lattice sites. Magnetic-film lattices on atom chips provide a versatile platform for experiments with ultracold atoms, in particular for quantum information science and quantum simulation.

Coupling between internal spin dynamics and external degrees of freedom in the presence of colored noise.

We observe asymmetric transition rates between Zeeman levels (spin flips) of magnetically trapped atoms. The asymmetry strongly depends on the spectral shape of an applied noise. This effect follows from the interplay between the internal states of the atoms and their external degrees of freedom, where different trapped levels experience different potentials. Such insight may prove useful for controlling atomic states by the introduction of noise, as well as provide a better understanding of the effect of noise on the coherent operation of quantum systems.

Retroreflecting polarization spectroscopy enabling miniaturization.

We describe and characterize alternative configurations for Doppler-free polarization spectroscopy. The suggested apparatus enables complete pump/probe beam overlap and allows substantial miniaturization. Its utility and performance for narrow linewidth, high-stability frequency locking is discussed for the /5S(1/2)F=2>-->/5P(3/2)F(')>D(2) transition in (87)Rb.

Long-range order in electronic transport through disordered metal films.

Ultracold atom magnetic field microscopy enables the probing of current flow patterns in planar structures with unprecedented sensitivity. In polycrystalline metal (gold) films, we observed long-range correlations forming organized patterns oriented at +/-45 degrees relative to the mean current flow, even at room temperature and at length scales larger than the diffusion length or the grain size by several orders of magnitude. The preference to form patterns at these angles is a direct consequence of universal scattering properties at defects. The observed amplitude of the current direction fluctuations scales inversely to that expected from the relative thickness variations, the grain size, and the defect concentration, all determined independently by standard methods. Ultracold atom magnetometry thus enables new insight into the interplay between disorder and transport.

Using time-reversal symmetry for sensitive incoherent matter-wave Sagnac interferometry.

We present a theory of the transmission of guided matter-waves through Sagnac interferometers. Interferometer configurations with only one input and one output port have a property similar to the phase rigidity observed in the transmission through Aharonov-Bohm interferometers in coherent mesoscopic electronics. This property enables their operation with incoherent matter-wave sources. High rotation sensitivity is predicted for high finesse configurations.

Atom fiber for omnidirectional guiding of cold neutral atoms.

We present an omnidirectional matter waveguide on an atom chip. The guide is based on a combination of two current-carrying wires and a bias field pointing perpendicular to the chip surface. Thermal atoms are guided for more than two complete turns along a 25-mm-long spiral path (with curve radii as short as 200 microm) at various atom-surface distances (35-450 microm). An extension of the scheme for the guiding of Bose-Einstein condensates is outlined.

Trapping and manipulating neutral atoms with electrostatic fields.

We report on experiments with cold thermal (7)Li atoms confined in combined magnetic and electric potentials. A novel type of three-dimensional trap was formed by modulating a magnetic guide using electrostatic fields. We observed atoms trapped in a string of up to six individual such traps, a controlled transport of an atomic cloud over a distance of 400 microm, and a dynamic splitting of a single trap into a double well potential. Applications for quantum information processing are discussed.

Controlling cold atoms using nanofabricated surfaces: atom chips

Atoms can be trapped and guided using nanofabricated wires on surfaces, achieving the scales required by quantum information proposals. These atom chips form the basis for robust and widespread applications of cold atoms ranging from atom optics to fundamental questions in mesoscopic physics, and possibly quantum information systems.

Beam splitter for guided atoms.

We have designed and experimentally studied a simple beam splitter for guided atoms realized with a current carrying Y-shaped wire nanofabricated on a surface (atom chip). Such a Y-configuration beam splitter has many advantages compared to conventional designs based on tunneling, especially that it will enable robust beam splitting. This and other similar designs can be integrated into more sophisticated surface-mounted atom optical devices at the mesoscopic scale.

Experience with mitomycin in the treatment of non-small cell lung cancer.

Mitomycin has proven to be among the most active drugs available for the single-agent treatment of non-small cell lung cancer (NSCLC). In combination with vinca alkaloids and cisplatin, mitomycin can produce response rates greater than or equal to 50% in properly selected patients. In our experience, such responses were achieved using moderate doses (7 or 8 mg/m2) of mitomycin, which also resulted in fewer hematologic and other toxicities. Delivery of MVP (mitomycin/vinca alkaloid/cisplatin) to 150 patients with stages III and IV NSCLC during the last decade showed maximal response was achieved after two or three cycles of therapy. A comparative analysis of results reported using MVP regimens suggests that high response rates are associated with greater dose-intensive use of cisplatin and lesser dose-intensive use of mitomycin. Although the role of MVP in the treatment of advanced NSCLC is unclear, use of mitomycin-containing regimens as part of a multidisciplinary approach to stage IIIA NSCLC has yielded high response rates and has successfully downstaged patients prior to surgery. Randomized clinical trials will be required to validate these findings, but the focus of future research should be on discovering new agents with greater activity and on developing new approaches wherein these agents can be delivered with maximum efficacy and minimum toxicity.

Multidisciplinary management of non-small cell lung cancer in the community.

A community-based, multidisciplinary approach, incorporating chemotherapy may provide benefit to patients with non-small cell lung cancer. Drug-induced cytoreduction may make it possible to perform surgery on patients hitherto inoperable, and may facilitate radiotherapy in other patients with regionally advanced disease. Several criteria must be met before the institution of this approach. The drugs selected must be effective in a majority of patients and toxic side effects must be within tolerable limits; candidates must be screened carefully with regard to age, stage, histology, performance status, past medical history, and they should be able to understand the potential risks involved. Importantly, support must be obtained from referring physicians, surgeons, and radiation therapists.

Office screening for urinary tract infections in infancy.

A retrospective report of the experience of nine years of simplified office screening for infantile urinary tract infection (UTI) is compared with the more invasive and stringent methodology widely considered necessary. Urine samples were obtained from 1313 infants of two years or less. In 27 of these infants UTI was diagnosed and the data analysed from 24 cases. Nine infants were completely asymptomatic, while the rest had non-specific symptoms. Radiological investigations were carried out in all the infants with UTI. Urine samples were obtained without any specific precleansing of the perineum, and the criteria for diagnosing UTI were two consecutive positive cultures. The results were statistically similar to studies in which there was pre-cleansing, and in which the criteria were three consecutive positive cultures.

The role of chemotherapy in non-small cell lung cancer: the community perspective.

In the past decade, several drugs have been identified that possess activity in treating non-small cell lung cancer (NSCLC). The combination of mitomycin C, vinblastine, and cisplatin (MVP) was studied in 56 previously untreated patients with advanced NSCLC in Bridgeport Hospital from 1981 to 1984. In a selected patient population, 73% of 52 evaluable patients had complete (four patients) or partial (34 patients) responses. Response rate was 88% in epidermoid carcinoma, 70% in adenocarcinoma, and 50% in undifferentiated carcinoma. Median survival was 10 months in responding patients v 4 months in nonresponders. Performance status was the most important factor predictive of prolonged survival. MVP cannot be recommended for patients with poor performance status but may offer worthwhile palliation to patients with advanced NSCLC. Active drug combinations must now be studied as part of a multidisciplinary approach to the primary management of patients with clinically localized NSCLC.

Increased rates of polypeptide chain elongation in placental explants from human diabetics.

Average rates of polypeptide chain elongation were determined in placental explants of first trimester and term placentas from both normal and diabetic human pregnancies. Average ribosome half-transit times were determined by measuring the kinetics of transfer of labeled polypeptides from polysomal-bound to released polypeptides. The average half-transit time decreases from 75 sec per ribosome in first trimester explants to 56 sec per ribosome in term placentas. The average polypeptide molecular weights synthesized by explants from first trimester and in term are 49,300 and 49,600, respectively, which are not significantly different. The average elongation rates for first trimester and term placental explants are 172 and 231 amino acids per minute per ribosome, respectively, which are significantly different. Moreover, the average polypeptide molecular weight synthesized by term placentas from diabetic pregnancies is 48,200, while the average ribosome half-transit time is 40 sec. Thus, ribosomes from explants of term placenta from diabetics move along the average message at a much higher speed than do ribosomes in normal term tissue. The assembly rate of amino acid into polypeptide in explant of placenta of diabetic mothers is 314 amino acids per minute, which is significantly faster than 231 amino acids per minute in normal term tissue. These findings indicate that during placental development and in diabetic pregnancy there is a large change in the actual rates at which amino acids are added to the nascent polypeptide chain--i.e., the rates in polypeptide chain elongation. Therefore, translation-level regulation of protein synthesis in placenta plays a significant part in the magnitude of the response to developmental and other physiological stimulations.

The in vitro synthesis and secretion of alkaline phosphatase from first trimester human decidua.

We studied the in vitro synthesis and secretion of alkaline phosphatase by human first trimester decidual tissue incubated in organ culture. Decidua synthesizes two different alkaline phosphatase isoenzymes; heat stable and heat labile. decidual tissue maintains a constant pool of alkaline phosphatases. The synthesis of alkaline phosphatase may be the driving force for its secretion. The de novo synthesis and secretion rate of alkaline phosphatases were also investigated. The higher specific radioactivities of the secreted enzymes than those found in the tissue may suggest that newly synthesized alkaline phosphatase is preferentially released. The intracellular distribution of the alkaline phosphatase isoenzymes was compared as well. The characteristics of the two isoenzymes are different in human decidua of maternal origin from those previously reported in the human placenta originating from embryonic stem cells.

The synthesis and secretion of human placental lactogen (hPL) in cultured term placenta.

We studied the in vitro synthesis and secretion of hPL by human term placental tissue incubated in organ culture. Placental tissue maintains a constant pool of hPL. The synthesis of hPL may be the driving force for its secretion. The de novo synthesis and secretion rates of hPL were also investigated. The higher specific radioactivities of the secreted hPL than those found in the tissue may suggest that newly synthesized hPL is preferentially released. The intracellular distribution of hPL was also compared.