Observation of Momentum Space Josephson Effects in Weakly Coupled Bose-Einstein Condensates.

The momentum space Josephson effect describes the supercurrent flow between weakly coupled Bose-Einstein condensates (BECs) at two discrete momentum states. Here, we experimentally observe this exotic phenomenon using a BEC with Raman-induced spin-orbit coupling, where the tunneling between two local band minima is implemented by the momentum kick of an additional optical lattice. A sudden quench of the Raman detuning induces coherent spin-momentum oscillations of the BEC, which is analogous to the ac Josephson effect. We observe both plasma and regular Josephson oscillations in different parameter regimes. The experimental results agree well with the theoretical model and numerical simulation and showcase the important role of nonlinear interactions. We also show that the measurement of the Josephson plasma frequency gives the Bogoliubov zero quasimomentum gap, which determines the mass of the corresponding pseudo-Goldstone mode, a long-sought phenomenon in particle physics. The observation of momentum space Josephson physics offers an exciting platform for quantum simulation and sensing utilizing momentum states as a synthetic degree.

Quantum gas mixtures and dual-species atom interferometry in space.

The capability to reach ultracold atomic temperatures in compact instruments has recently been extended into space1,2. Ultracold temperatures amplify quantum effects, whereas free fall allows further cooling and longer interactions time with gravity-the final force without a quantum description. On Earth, these devices have produced macroscopic quantum phenomena such as Bose-Einstein condensates (BECs), superfluidity, and strongly interacting quantum gases3. Terrestrial quantum sensors interfering the superposition of two ultracold atomic isotopes have tested the universality of free fall (UFF), a core tenet of Einstein's classical gravitational theory, at the 10-12 level4. In space, cooling the elements needed to explore the rich physics of strong interactions or perform quantum tests of the UFF has remained elusive. Here, using upgraded hardware of the multiuser Cold Atom Lab (CAL) instrument aboard the International Space Station (ISS), we report, to our knowledge, the first simultaneous production of a dual-species BEC in space (formed from 87Rb and 41K), observation of interspecies interactions, as well as the production of 39K ultracold gases. Operating a single laser at a 'magic wavelength' at which Rabi rates of simultaneously applied Bragg pulses are equal, we have further achieved the first spaceborne demonstration of simultaneous atom interferometry with two atomic species (87Rb and 41K). These results are an important step towards quantum tests of UFF in space and will allow scientists to investigate aspects of few-body physics, quantum chemistry and fundamental physics in new regimes without the perturbing asymmetry of gravity.

The current role of surgery in the treatment of cardiac metastases from malignant melanoma: an educational presentation

Abstract A 71 year-old male with a history of multiple excisions of an initial Clark's level V melanoma of the breast followed by combined radiation and interferon treatment, as well as a recurrence, 3 years later, of a BRAF-positive tumor of the shoulder, with subsequent therapy with dabrafenib and trametinib, presented again with progressive intracardiac masses causing significant right ventricular outflow obstruction. Additionally, the patient complained of dyspnea and fatigue on exertion, thus he was scheduled for surgical resection.

The Current Role of Surgery in the Treatment of Cardiac Metastases from Malignant Melanoma: an Educational Presentation.

A 71 year-old male with a history of multiple excisions of an initial Clark's level V melanoma of the breast followed by combined radiation and interferon treatment, as well as a recurrence, 3 years later, of a BRAF-positive tumor of the shoulder, with subsequent therapy with dabrafenib and trametinib, presented again with progressive intracardiac masses causing significant right ventricular outflow obstruction. Additionally, the patient complained of dyspnea and fatigue on exertion, thus he was scheduled for surgical resection.

Experimental realization of a non-magnetic one-way spin switch.

Controlling magnetism through non-magnetic means is highly desirable for future electronic devices, as such means typically have ultra-low power requirements and can provide coherent control. In recent years, great experimental progress has been made in the field of electrical manipulation of magnetism in numerous material systems. These studies generally do not consider the directionality of the applied non-magnetic potentials and/or magnetism switching. Here, we theoretically conceive and experimentally demonstrate a non-magnetic one-way spin switch device using a spin-orbit coupled Bose-Einstein condensate subjected to a moving spin-independent repulsive dipole potential. The physical foundation of this unidirectional device is based on the breakdown of Galilean invariance in the presence of spin-orbit coupling. Such a one-way spin switch opens an avenue for designing quantum devices with unique functionalities and may facilitate further experimental investigations of other one-way spintronic and atomtronic devices.

Momentum-Space Josephson Effects.

The Josephson effect is a prominent phenomenon of quantum supercurrents that has been widely studied in superconductors and superfluids. Typical Josephson junctions consist of two real-space superconductors (superfluids) coupled through a weak tunneling barrier. Here we propose a momentum-space Josephson junction in a spin-orbit coupled Bose-Einstein condensate, where states with two different momenta are coupled through Raman-assisted tunneling. We show that Josephson currents can be induced not only by applying the equivalent of "voltages," but also by tuning tunneling phases. Such tunneling-phase-driven Josephson junctions in momentum space are characterized through both full mean field analysis and a concise two-level model, demonstrating the important role of interactions between atoms. Our scheme provides a platform for experimentally realizing momentum-space Josephson junctions and exploring their applications in quantum-mechanical circuits.

Oxygenation Status in Chronic Leg Ulcer After Topical Hemoglobin Application May Act as a Surrogate Marker to Find the Best Treatment Strategy and to Avoid Ineffective Conservative Long-term Therapy.

PURPOSE: Chronic leg ulcers can be a challenge to treat and long-term therapy a significant cost factor in western public health budgets. Objective wound assessment assays enabling selection of appropriate wound therapy regimes would be desirable. Oxygenation status in ulcer tissue has obtained increased attention as a relevant factor in wound healing. To increase oxygenation in wounds, a topical hemoglobin spray was developed. Although favorable results have been noted, the link between clinical efficacy and the mode of action has not been demonstrated. The aims were to determine if changes in tissue oxygenation can be measured after topical application of hemoglobin on chronic wounds and to evaluate the findings in terms of therapy strategies. PROCEDURES: Photoacoustic imaging was used to measure the local oxygen saturation (StO2) in leg ulcers before and after hemoglobin spray treatment. Sclerosis of the leg ulcers was histopathologically graded and the change in wound size was documented in a follow-up examination. RESULTS: Measuring 49 patients, an increase in StO2 after topical hemoglobin application from on average 66.1 to 71 % (p = 0.017) after 20 min was observed. Depending on the increase in StO2 (>10 % or <10 %) patients were stratified into a Responder and a Non-Responder group. Wound size significantly decreased in the Responder Group (p = 0.001), while no significant difference in the Non-Responder group (p = 0.950) was noted. CONCLUSION: Our findings suggest that the likelihood of wound healing under conservative therapy can be predicted by measuring changes in StO2 after topical hemoglobin application. This assay may reduce treatment time and costs by avoiding ineffective conservative long-term therapy. TRIAL REGISTRATION: German Clinical Trials Register: DRKS00005993.

Dicke-type phase transition in a spin-orbit-coupled Bose-Einstein condensate.

Spin-orbit-coupled Bose-Einstein condensates (BECs) provide a powerful tool to investigate interesting gauge field-related phenomena. Here we study the ground state properties of such a system and show that it can be mapped to the well-known Dicke model in quantum optics, which describes the interactions between an ensemble of atoms and an optical field. A central prediction of the Dicke model is a quantum phase transition between a superradiant phase and a normal phase. We detect this transition in a spin-orbit-coupled BEC by measuring various physical quantities across the phase transition. These quantities include the spin polarization, the relative occupation of the nearly degenerate single-particle states, the quantity analogous to the photon field occupation and the period of a collective oscillation (quadrupole mode). The applicability of the Dicke model to spin-orbit-coupled BECs may lead to interesting applications in quantum optics and quantum information science.

Wound management with compression therapy and topical hemoglobin solution in a patient with Budd-Chiari Syndrome.

BACKGROUND: Although the underlying primary cause of chronic wounds may vary, a common etiology of this is a hypoxic or ischemic status of the affected tissue of the lower extremities. In particular, for rare diseases associated with disturbed blood flow a correlation between cause and effect is often diagnosed inappropriately. As a consequence, chronic wounds may develop and persist for years. MAIN OBSERVATIONS: We present a case of a patient with chronic venous insufficiency due to an occlusion of the inferior caval vein. Initially, a Budd-Chiari syndrome was diagnosed which is a thrombotic obstruction of the hepatic venous outflow. In addition, the patient developed an obstruction of the inferior caval vein and subsequently a chronic venous insufficiency. As a consequence, chronic leg ulcers developed with a history of more than 7 years. Various wound care approaches were performed without success in wound closure. Finally, a combination of compression therapy and topical application of a hemoglobin solution successfully led to fast and persistent wound closure. CONCLUSIONS: Chronic ulcers of the lower limb such as venous leg ulcers, even for patients with rare disorders like Budd-Chiari syndrome, are associated with oxygen supply disturbances resulting in a hypoxic status of the affected tissue. Therefore, an adequate oxygen supply to chronic wounds plays a pivotal role in successful wound healing. Compression therapy in combination with enhancement of the local oxygen supply by topically applied hemoglobin showed marked improvement of wound healing in the presented patient.

Clinical results of the application of a hemoglobin spray to promote healing of chronic wounds.

A new technological approach for supplying hypoxic chronic wounds with oxygen is a moist wound treatment with aqueous solutions containing tissue compatible oxygen binders. This facilitates diffusion of oxygen, necessary for the healing process, from the surroundings (room air through an open-porous wound padding) into the ulcerous tissue. A product that is still in development is a spray which contains hemoglobin obtained from domestic pigs. Clinical investigations (a clinical trial, treatment observations and single patient uses) are presented, which were performed to create clinical data regarding efficiency and safety of this product. All data have shown that the application of the hemoglobin spray promoted wound healing in all analyzed cases.Data from a clinical study in Mexico and subsequent therapy observations revealed that in 39 out of 42 patients (93%) the treated wounds were healed. 9 patients from a series of therapy observations in Monterrey (Mexico) showed similar observations. All treated wounds were closed. Single patient uses carried out in Witten (Germany; 6 wounds from 8 (75%)) and Prague (Czech Republic; 5 wounds from 5 (100%) were healed) further support these results: The application of hemoglobin spray can promote healing of chronic wounds. Within the framework of the clinical investigation, the treatment observations, and the individual healing experiments the hemoglobin spray was applied more than 2,000 times onto chronic wounds of 82 patients. In all cases, the spray was well tolerated and there were no adverse event that might have been an adverse reaction to the hemoglobin spray.

Influence of different promoters on the expression pattern of mutated human alpha-synuclein in transgenic mice.

Two missense mutations (A53T and A30P) in the gene encoding the presynaptic protein alpha-synuclein (asyn) are associated with rare, dominantly inherited forms of Parkinson's disease (PD) and its accumulation in Lewy bodies and Lewy neurites. As an initial step in investigating the role of asyn in the pathogenesis of PD, we have generated C57BL/6 transgenic mice overexpressing the doubly mutated human asyn under the control of three different promoters; the chicken beta-actin (chbetaactin), the mouse tyrosine hydroxylase 9.6 kb (msTH) and the mouse prion protein (msprp). In this study we compared the regional and cellular expression pattern of the transgenic protein in the brain and peripheral organs of various transgenic mouse lines. Western blot analysis and immunohistochemistry consistently showed that all three promoters successfully drive the expression of the transgene. The msprp promoter was found to give the highest level of transgene expression. All promoters directed the expression into the brain and specific neuron types. However, the promoters differed with respect to (i) the expression pattern in peripheral organs, (ii) the number and (iii) the regional distribution of expressing cells in the brain. Furthermore, remarkable line-to-line variation of expression patterns was observed in mouse lines carrying the same construct. Future studies will analyze how the variations in transgene expression affect the pathogenesis in the animals.