Majorana modes in driven-dissipative atomic superfluids with a zero Chern number

We investigate dissipation-induced p-wave paired states of fermions in two dimensions and show the existence of spatially separated Majorana zero modes in a phase with vanishing Chern number. We construct an explicit and natural model of a dissipative vortex that traps a single of these modes, and establish its topological origin by mapping the problem to a chiral one-dimensional wire where we observe a nonequilibrium topological phase transition characterized by an abrupt change of a topological invariant (winding number). We show that the existence of a single Majorana zero mode in the vortex core is intimately tied to the dissipative nature of our model. Engineered dissipation opens up possibilities for experimentally realizing such states with no Hamiltonian counterpart.

Placement of an aortomonoiliac stent graft without femorofemoral revascularization in endovascular aneurysm repair: a case report

Introduction

Endovascular aortic repair, if technically feasible, is the treatment of choice for patients with a contained ruptured aortic aneurysm who are unfit for open surgery.

Case presentation

We report the case of an 80-year-old Caucasian man who presented with an unusually configured, symptomatic infrarenal aortic aneurysm. His aneurysm showed an erosion of the fourth lumbar vertebra and a severely arteriosclerotic pelvic axis. A high thigh amputation of his right leg had been performed 15 months previously. On his right side, occlusion of his external iliac artery, common femoral artery, and deep femoral artery had occurred. His aneurysm was treated by a left-sided aortomonoiliac stent graft without femorofemoral revascularization, resulting in occlusions of both internal iliac arteries. No ischemic symptoms appeared, although perfusion of his right side was maintained only over epigastric collaterals.

Conclusions

The placement of aortomonoiliac stent grafts for endovascular treatment of infrarenal aortic aneurysms without contralateral revascularization is a feasible treatment option in isolated cases. In this report, access problems and revascularization options in endovascular aneurysm repair are discussed.

Effective continuous systemic therapy of severe plaque-type psoriasis is accompanied by amelioration of biomarkers of cardiovascular risk: results of a prospective longitudinal observational study

BACKGROUND

Severe psoriasis is associated with significant cardiovascular mortality.

OBJECTIVES

We investigated the effects of continuous systemic therapy on the cardiovascular risk of patients with severe plaque-type psoriasis.

METHODS

A total of 42 consecutive patients receiving systemic treatment for their severe plaque-type psoriasis were included. The clinical course was monitored over 24 weeks. Initially as well as after 12 and 24 weeks, oral glucose tolerance tests were performed along with comprehensive laboratory monitoring.

RESULTS

Responding patients, defined as a Psoriasis Area and Severity Index (PASI)-50 response, showed correlations between the PASI and high-sensitive C-reactive protein (r = 0.45, P = 0.03) as well as with vascular endothelial growth factor (r = 0.76, P = 0.007). The adipokine resistin was positively and the potentially cardio-protective adiponectin was negatively correlated with the PASI (r = 0.50, P = 0.02 and r = -0.56, P = 0.007, respectively). Oral glucose tolerance tests yielded a correlation between the PASI and plasma levels for C-peptide (r = 0.73, P = 0.02) at t = 120 min in patients with a pathological Homeostasis Model Assessment (>2.5), indicating that the state of peripheral insulin resistance is driven at least in part by the severity of the psoriatic inflammation. Correlations between the change of adipokine levels and change in PASI were more pronounced among patients with better clinical improvement (PASI-75 vs. PASI-50).

CONCLUSIONS

We document an amelioration of biomarkers of cardiovascular risk in patients with severe plaque-type psoriasis responding to continuous systemic therapy. The impact on the patients'metabolic state was found to be better if the psoriatic inflammation was controlled for longer. Future studies need to compare the cardioprotective effects of different treatment modalities, based on hard clinical endpoints.

Dissipation-induced d-wave pairing of fermionic atoms in an optical lattice

We show how dissipative dynamics can give rise to pairing for two-component fermions on a lattice. In particular, we construct a parent Liouvillian operator so that a BCS-type state of a given symmetry, e.g., a d-wave state, is reached for arbitrary initial states in the absence of conservative forces. The system-bath couplings describe single-particle, number-conserving and quasilocal processes. The pairing mechanism crucially relies on Fermi statistics. We show how such Liouvillians can be realized via reservoir engineering with cold atoms representing a driven dissipative dynamics.

Graph-matching-based computed tomography angiography in peripheral arterial occlusive disease

The objective of this study is to compare a graph-matching-based software and a conventional tool for postprocessing of computed tomography angiography (CTA) in correlation with the gold standard digital subtraction angiography. Sensitivity, specificity, accuracy, and interobserver agreement increased from 80.3% to 92.9%, from 69.1% to 92.4%, from 73.5% to 92.8%, and from 0.45 to 0.96, respectively, using the graph-matching-based technique. Graph-matching-based CTA increases sensitivity, specificity, accuracy, and interobserver agreement in comparison to a conventional bone elimination tool in the assessment of peripheral arterial occlusive disease.

Observability of quantum criticality and a continuous supersolid in atomic gases

We analyze the Bose-Hubbard model with a three-body hard-core constraint by mapping the system to a theory of two coupled bosonic degrees of freedom. We find striking features that could be observable in experiments, including a quantum Ising critical point on the transition from atomic to dimer superfluidity at unit filling, and a continuous supersolid phase for strongly bound dimers.

Atomic color superfluid via three-body loss

Large three-body loss rates in a three-component Fermi gas confined in an optical lattice can dynamically prevent atoms from tunneling so as to occupy a lattice site with three atoms. This effective constraint not only suppresses the occurrence of actual loss events, but stabilizes BCS-pairing phases by suppressing the formation of trions. We study the effect of the constraint on the many-body physics using bosonization and density matrix renormalization group techniques, and also investigate the full dissipative dynamics including loss for the example of 6Li.

Graph-matching based CTA

Separating bone, calcification, and vessels in computer tomography angiography (CTA) allows for a detailed diagnosis of vessel stenosis. This paper presents a new, graph-based technique that solves this difficult problem with high accuracy. The approach requires one native data set and one that is contrast enhanced. On each data set, an attributed level-graph is derived and both graphs are matched by dynamic programming to differentiate between bone, on one hand side, and vessel/calcification on the other hand side. Lumen and calcified regions are then separated by a profile technique. Evaluation is based on data from vessels of pelvis and lower extremities of elderly patients. Due to substantial calcification and motion of patients between and during the acquisitions, the underlying approach is tested on a class of difficult cases. Analysis requires 3-5 min on a Pentium IV 3 GHz for a 700 MByte data set. Among 37 patients, our approach correctly identifies all three components in 80% of cases correctly compared to visual control. Critical inconsistencies with visual inspection were found in 6% of all cases; 70% of these inconsistencies are due to small vessels that have 1) a diameter near the resolution of the CT and 2) are passing next to bony structures. All other remaining deviations are found in an incorrect handling of the iliac artery since the slice thickness is near the diameter of this vessel and since the orientation is not in cranio-caudal direction. Increasing resolution is thus expected to solve many the aforementioned difficulties.

Treatment monitoring with 18F-FDG PET in metastatic thymoma after 90Y-Dotatoc and selective internal radiation treatment (SIRT)

A 39 years old male patient with a history of an unresectable thymoma and synchronous liver metastases was referred tor our position. The patient had been originally treated with systemic chemotherapy followed by imatinib (Glivec) and sunitinib (Sutent). Since the therapeutic response was unsatisfactory, a gallium-68 ((68)Ga)-Dotatoc-positron emission tomography (PET) was performed and demonstrated an enhanced SSTR 2 expression in the primary tumor but not in the liver metastases. Three cycles of yttrium-90 ((90)Y)-Dotatoc were then administered. Outcome after treatment was monitored by (18)F-FDG-PET and CT and showed a response only of the primary tumor. Selective internal radiation treatment (SIRT) with (90)Y microspheres was then applied for the liver metastases. (18)F-FDG uptake showed that metabolism in the liver metastases decreased after SIRT. MRI of the liver demonstrated a decrease in vascularization and a modest decrease in tumor volume. Therefore, surgical resection of the primary thymoma was initiated.

Stabilization of the p-wave superfluid state in an optical lattice

It is hard to stabilize the p-wave superfluid state of cold atomic gas in free space due to inelastic collisional losses. We consider the p-wave Feshbach resonance in an optical lattice, and show that it is possible to have a stable p-wave superfluid state where the multiatom collisional loss is suppressed through the quantum Zeno effect. We derive the effective Hamiltonian for this system, and calculate its phase diagram in a one-dimensional optical lattice. The results show rich phase transitions between the p-wave superfluid state and different types of insulator states induced either by interaction or by dissipation.

Atomic three-body loss as a dynamical three-body interaction

We discuss how large three-body loss of atoms in an optical lattice can give rise to effective hard-core three-body interactions. For bosons, in addition to the usual atomic superfluid, a dimer superfluid can then be observed for attractive two-body interactions. The nonequilibrium dynamics of preparation and stability of these phases are studied in 1D by combining time-dependent density matrix renormalization group techniques with a quantum trajectories method.

SNPs upstream of the minimal promoter control IL-2 expression and are candidates for the autoimmune disease-susceptibility locus Aod2/Idd3/Eae3

IL-2, a T-cell growth and differentiation factor, plays an important role in immune homeostasis. Previously, we identified IL2 as a candidate for Aod2, a quantitative trait locus (QTL) controlling susceptibility to autoimmune ovarian dysgenesis (AOD) induced by day 3 neonatal thymectomy. Here, we report the identification of single-nucleotide polymorphisms (SNPs) in a region upstream of the minimal IL2 promoter (-2.8 kb to -300 bp), which distinguish AOD-susceptible A/J and AOD-resistant C57BL/6J (B6/J) mice. Six of the SNPs (-1010 C --> T, -962 C --> T, -926/-925 Delta Delta --> AC, -921 T --> C, -914 T --> C and -674 G --> A) contribute to the enhanced transcriptional activity of the extended B6/J promoter relative to A/J. Importantly, the -1010 SNP resides within a canonical AP-1-binding motif with the C --> T transition at this site abrogating AP-1 binding. Moreover, these SNPs segregate with differential production of IL-2 by CD4(+) T cells as well as susceptibility alleles at Idd3 and Eae3, QTL controlling insulin-dependent diabetes mellitus and experimental allergic encephalomyelitis. These are the first SNPs identified within the extended murine IL2 promoter that control differential IL-2 transcription in CD4(+) T cells, and, as such, they are not only candidates for Aod2, but are also candidates for a shared autoimmune disease-susceptibility locus underlying Idd3 and Eae3.

Intensity inversion between main and satellite lines in atomic photoionization

The 1s photoionization of atomic Li was studied by photoelectron spectroscopy in the photon energy region between 85 and 140 eV for the ground state and the three lowest excited configurations Li(*) 1s(2)nl, nl=2p, 3s, 3p. The importance of electron correlations was investigated by comparing the multielectron transitions, so-called shake-up and conjugate shake-up satellites, and the direct process, so-called main lines. The relative intensity of the satellites increases with the level of initial excitation of the Li atom. The shake-up process dominates for states with an n=3 valence electron and the satellites become stronger than the main lines. This spectacular effect can be explained by the spatial overlap of the initial and final state wave functions. Surprisingly, the spatial overlap affects shake-up and conjugate shake-up lines in the same way.