Quantum State Engineering of a Hubbard System with Ultracold Fermions

Accessing new regimes in quantum simulation requires the development of new techniques for quantum state preparation. We demonstrate the quantum state engineering of a strongly correlated many-body state of the two-component repulsive Fermi-Hubbard model on a square lattice. Our scheme makes use of an ultralow entropy doublon band insulator created through entropy redistribution. After isolating the band insulator, we change the underlying potential to expand it into a half-filled system. The final many-body state realized shows strong antiferromagnetic correlations and a temperature below the exchange energy. We observe an increase in entropy, which we find is likely caused by the many-body physics in the last step of the scheme. This technique is promising for low-temperature studies of cold-atom-based lattice models.

Treatment of SEC62 over-expressing tumors by Thapsigargin and Trifluoperazine

Treatment with analogues of the SERCA-inhibitor Thapsigargin is a promising new approach for a wide variety of cancer entities. However, our previous studies on various tumor cells suggested resistance of SEC62 over-expressing tumors to this treatment. Therefore, we proposed the novel concept that e.g. lung-, prostate-, and thyroid-cancer patients should be tested for SEC62 over-expression, and developed a novel therapeutic strategy for a combinatorial treatment of SEC62 over-expressing tumors. The latter was based on the observations that treatment of SEC62 over-expressing tumor cells with SEC62-targeting siRNAs showed less resistance to Thapsigargin as well as a reduction in migratory potential and that the siRNA effects can be mimicked by the Calmodulin antagonist Trifluoperazine. Therefore, the combinatorial treatment of SEC62 over-expressing tumors was proposed to involve Thapsigargin and Trifluoperazine. Here, we addressed the impact of Thapsigargin and Trifluoperazine in separate and combined treatments of heterotopic tumors, induced by inoculation of human hypopharyngeal squamous cell carcinoma (FaDu)-cells into the mouse flank. Seeding of the tumor cells and/or their growth rate were significantly reduced by all three treatments, suggesting Trifluoperazine is a small molecule to be considered for future therapeutic strategies for patients, suffering from Sec62-overproducing tumors.

Effect of 3q oncogenes SEC62 and SOX2 on lymphatic metastasis and clinical outcome of head and neck squamous cell carcinomas

Chromosome 3q26 amplification represents a frequent alteration in head and neck squamous cell carcinomas (HNSCCs). Overexpression of 3q26 encoded genes SEC62 and SOX2 was detected in various cancers, including HNSCCs, indicating their potential function as oncogenes. In our study, we elucidated the function of SEC62 and SOX2 in HNSCC patients, with a main focus on their effect on lymphatic metastasis and patient survival. We analyzed SEC62 and SOX2 expression in tissue specimens from 65 HNSCC patients and 29 patients with cervical cancer of unknown primary (CUP); a higher SEC62 and lower SOX2 expression was observed in the lymph node metastases from HNSCC patients compared with the respective primary tumor. Lymph node metastases from CUP patients showed higher SEC62 and lower SOX2 expression compared with lymph node metastases from HNSCC patients. When proceeding from the N1 to the N3 stage, SEC62 expression in the lymph node metastases showed an increase and SOX2 expression showed a decrease. Moreover, both genes showed a highly significant relevance as prognostic biomarkers, with the worst prognosis for patients with high SEC62 and low SOX2 expression levels. In functional analyses, knockdown of SEC62 resulted in an inhibition of HNSCC cell migration while, conversely, SEC62 and SOX2 overexpression stimulated cell migration. Taken together, our study showed that the expression of the 3q oncogenes SEC62 and SOX2 affects lymphatic metastasis and cell migration in HNSCC and CUP patients and has a high prognostic relevance in these diseases.

Abstract P6-09-10: Provider characteristics and receipt of oncotype Dx testing in women diagnosed with early stage breast cancer using SEER-Medicare data

Background: Oncotype DX (ODX) genomic testing to evaluate recurrence risk and benefit of adjuvant chemotherapy in patients with ER-positive, node-negative breast cancers was approved for Medicare reimbursement in 2006. We previously examined patient-level factors associated with utilization of ODX testing from 2005-2009 in the SEER-Medicare population; ODX testing occurred most frequently in patients with ER+, node negative disease, with 80% of all tests occurring in patients aged 66-75. In our current study, we examined potential provider factors associated with patient-level ODX testing from 2008 to 2012.

Methods: Using a retrospective cohort design, we identified all individuals who had a SEER diagnosis of breast cancer from 2008-2011 and were enrolled in fee-for-service Medicare parts A and B for one year before and one year after diagnosis. We limited our analysis to individuals who had surgical resection of their breast tumor within 4 months of diagnosis and had a breast tumor which was ER+, invasive, and non-metastatic to capture the eligible patient population. Using Medicare claims data linked with the AMA physician dataset (which includes AMA members and non-members), we identified physician characteristics of the primary breast surgeon and medical oncologist including specialty, gender, years in practice, case volume, utilization of chemotherapy, and whether they serve rural populations. For patients with an ODX test, we used the identification on the claim to link to the performing provider. We examined the associations between provider characteristics and patient receipt of ODX testing using unadjusted and adjusted logistic regression models. Adjusted models included patient demographic and clinical characteristics.

Results: We identified 24,463 eligible breast cancer patients who received their care from 3172 primary surgeons and 2475 medical oncologists. Of 4124 ODX tests ordered for patients in the study, 70% were ordered by the assigned medical oncologist and 16% were ordered by the breast surgeon. In multivariable regression models, multiple physician characteristics were associated with receipt of ODX testing including having an assigned medical oncologist (OR 2.77, 95% CI 2.00-3.82), having a surgeon with a specialty of surgical oncology (OR 1.20, 95% CI 1.09-1.31), having a female medical oncologist (OR 1.10 95% CI 1.02-1.20). Having a medical oncologist with ≥5 years in practice was associated with lower odds of testing (OR 0.83 95% CI 0.76-0.92). Breast surgery performed at an academic hospital was associated with higher odds of ODX testing (OR 1.11 95% CI 1.02-1.20).

Conclusion: The majority of ODX testing for indicated breast cancer patients is ordered by medical oncologists, though surgeons and physicians of other specialties also order the tests in practice. Physician characteristics including gender and time in practice appear to affect a patient's likelihood of receiving ODX testing, creating opportunities for targeting interventions to help women with breast cancer receive optimal care.

Citation Format: Dinan MA, Wilson LE, Greiner M, Pollack CE. Provider characteristics and receipt of oncotype Dx testing in women diagnosed with early stage breast cancer using SEER-Medicare data [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P6-09-10.

Atom-by-atom assembly of defect-free one-dimensional cold atom arrays

The realization of large-scale fully controllable quantum systems is an exciting frontier in modern physical science. We use atom-by-atom assembly to implement a platform for the deterministic preparation of regular one-dimensional arrays of individually controlled cold atoms. In our approach, a measurement and feedback procedure eliminates the entropy associated with probabilistic trap occupation and results in defect-free arrays of more than 50 atoms in less than 400 milliseconds. The technique is based on fast, real-time control of 100 optical tweezers, which we use to arrange atoms in desired geometric patterns and to maintain these configurations by replacing lost atoms with surplus atoms from a reservoir. This bottom-up approach may enable controlled engineering of scalable many-body systems for quantum information processing, quantum simulations, and precision measurements.

Transient receptor potential melastatin 4 channel contributes to migration of androgen-insensitive prostate cancer cells

Impaired Ca²⁺ signaling in prostate cancer contributes to several cancer hallmarks, such as enhanced proliferation and migration and a decreased ability to induce apoptosis. Na⁺ influx via transient receptor potential melastatin 4 channel (TRPM4) can reduce store-operated Ca²⁺ entry (SOCE) by decreasing the driving force for Ca²⁺. In patients with prostate cancer, gene expression of TRPM4 is elevated. Recently, TRPM4 was identified as a cancer driver gene in androgen-insensitive prostate cancer.

We investigated TRPM4 protein expression in cancer tissue samples from 20 patients with prostate cancer. We found elevated TRPM4 protein levels in prostatic intraepithelial neoplasia (PIN) and prostate cancer tissue compared to healthy tissue. In primary human prostate epithelial cells (hPEC) from healthy tissue and in the androgen-insensitive prostate cancer cell lines DU145 and PC3, TRPM4 mediated large Na⁺ currents. We demonstrated significantly increased SOCE after siRNA targeting of TRPM4 in hPEC and DU145 cells. In addition, knockdown of TRPM4 reduced migration but not proliferation of DU145 and PC3 cells. Taken together, our data identify TRPM4 as a regulator of SOCE in hPEC and DU145 cells, demonstrate a role for TRPM4 in cancer cell migration and suggest that TRPM4 is a promising potential therapeutic target.

Quantum thermalization through entanglement in an isolated many-body system

Statistical mechanics relies on the maximization of entropy in a system at thermal equilibrium. However, an isolated quantum many-body system initialized in a pure state remains pure during Schrödinger evolution, and in this sense it has static, zero entropy. We experimentally studied the emergence of statistical mechanics in a quantum state and observed the fundamental role of quantum entanglement in facilitating this emergence. Microscopy of an evolving quantum system indicates that the full quantum state remains pure, whereas thermalization occurs on a local scale. We directly measured entanglement entropy, which assumes the role of the thermal entropy in thermalization. The entanglement creates local entropy that validates the use of statistical physics for local observables. Our measurements are consistent with the eigenstate thermalization hypothesis.

Identification of SEC62 as a potential marker for 3q amplification and cellular migration in dysplastic cervical lesions

Background

Chromosome 3 amplification affecting the 3q26 region is a common genomic alteration in cervical cancer, typically marking the transition of precancerous intraepithelial lesions to an invasive phenotype. Though potential 3q encoded target genes of this amplification have been identified, a functional correlation of potential oncogenic function is still missing. In this study, we investigated copy number changes and the expression level of SEC62 encoded at 3q26.2 as a new potential 3q oncogene in dysplastic cervical lesions and analyzed its role in cervical cancer cell biology.

Methods

Expression levels of Sec62 and vimentin were analyzed in liquid based cytology specimens from 107 women with varying grades of cervical dysplasia ranging from normal cases to cancer by immunofluorescence cytology. Additionally, a subset of 20 representative cases was used for FISH analyses targeting SEC62. To further explore the functional role of Sec62 in cervical cancer, HeLa cells were transfected with a SEC62 plasmid or SEC62 siRNA and analyzed for their proliferation and migration potential using real-time monitoring and trans-well systems as well as changes in the expression of EMT markers.

Results

FISH analyses of the swabbed cells showed a rising number of SEC62 gains and amplifications correlating to the grade of dysplasia with the highest incidence in high grade squamous intraepithelial lesions and squamous cell carcinomas. When analyzing the expression level of Sec62 and vimentin, we found a gradually increasing expression level of both proteins according to the severity of the dysplasia. In functional analyses, SEC62 silencing inhibited and SEC62 overexpression stimulated the migration of HeLa cells with only marginal effects on cell proliferation, the expression level of EMT markers and the cytoskeleton structure.

Conclusions

Our study suggests SEC62 as a target gene of 3q26 amplification and a stimulator of cellular migration in dysplastic cervical lesions. Hence, SEC62 could serve as a potential marker for 3q amplification, providing useful information about the dignity and biology of dysplastic cervical lesions.

Electronic supplementary material

The online version of this article (doi:10.1186/s12885-016-2739-6) contains supplementary material, which is available to authorized users.

Ultra-precise holographic beam shaping for microscopic quantum control

High-resolution addressing of individual ultracold atoms, trapped ions or solid state emitters allows for exquisite control in quantum optics experiments. This becomes possible through large aperture magnifying optics that project microscopic light patterns with diffraction limited performance. We use programmable amplitude holograms generated on a digital micromirror device to create arbitrary microscopic beam shapes with full phase and amplitude control. The system self-corrects for aberrations of up to several λ and reduces them to λ/50, leading to light patterns with a precision on the 10^-4 level. We demonstrate aberration-compensated beam shaping in an optical lattice experiment and perform single-site addressing in a quantum gas microscope for ⁸⁷Rb.

Applicability and feasibility of systematic review for performing evidence-based risk assessment in food and feed safety

Food and feed safety risk assessment uses multi-parameter models to evaluate the likelihood of adverse events associated with exposure to hazards in human health, plant health, animal health, animal welfare, and the environment. Systematic review and meta-analysis are established methods for answering questions in health care, and can be implemented to minimize biases in food and feed safety risk assessment. However, no methodological frameworks exist for refining risk assessment multi-parameter models into questions suitable for systematic review, and use of meta-analysis to estimate all parameters required by a risk model may not be always feasible. This paper describes novel approaches for determining question suitability and for prioritizing questions for systematic review in this area. Risk assessment questions that aim to estimate a parameter are likely to be suitable for systematic review. Such questions can be structured by their "key elements" [e.g., for intervention questions, the population(s), intervention(s), comparator(s), and outcome(s)]. Prioritization of questions to be addressed by systematic review relies on the likely impact and related uncertainty of individual parameters in the risk model. This approach to planning and prioritizing systematic review seems to have useful implications for producing evidence-based food and feed safety risk assessment.

Measuring entanglement entropy in a quantum many-body system

Entanglement is one of the most intriguing features of quantum mechanics. It describes non-local correlations between quantum objects, and is at the heart of quantum information sciences. Entanglement is now being studied in diverse fields ranging from condensed matter to quantum gravity. However, measuring entanglement remains a challenge. This is especially so in systems of interacting delocalized particles, for which a direct experimental measurement of spatial entanglement has been elusive. Here, we measure entanglement in such a system of itinerant particles using quantum interference of many-body twins. Making use of our single-site-resolved control of ultracold bosonic atoms in optical lattices, we prepare two identical copies of a many-body state and interfere them. This enables us to directly measure quantum purity, Rényi entanglement entropy, and mutual information. These experiments pave the way for using entanglement to characterize quantum phases and dynamics of strongly correlated many-body systems.

Co-chaperone Specificity in Gating of the Polypeptide Conducting Channel in the Membrane of the Human Endoplasmic Reticulum

In mammalian cells, signal peptide-dependent protein transport into the endoplasmic reticulum (ER) is mediated by a dynamic polypeptide-conducting channel, the heterotrimeric Sec61 complex. Previous work has characterized the Sec61 complex as a potential ER Ca(2+) leak channel in HeLa cells and identified ER lumenal molecular chaperone immunoglobulin heavy-chain-binding protein (BiP) as limiting Ca(2+) leakage via the open Sec61 channel by facilitating channel closing. This BiP activity involves binding of BiP to the ER lumenal loop 7 of Sec61α in the vicinity of tyrosine 344. Of note, the Y344H mutation destroys the BiP binding site and causes pancreatic β-cell apoptosis and diabetes in mice. Here, we systematically depleted HeLa cells of the BiP co-chaperones by siRNA-mediated gene silencing and used live cell Ca(2+) imaging to monitor the effects on ER Ca(2+) leakage. Depletion of either one of the ER lumenal BiP co-chaperones, ERj3 and ERj6, but not the ER membrane-resident co-chaperones (such as Sec63 protein, which assists BiP in Sec61 channel opening) led to increased Ca(2+) leakage via Sec6 complex, thereby phenocopying the effect of BiP depletion. Thus, BiP facilitates Sec61 channel closure (i.e. limits ER Ca(2+) leakage) via the Sec61 channel with the help of ERj3 and ERj6. Interestingly, deletion of ERj6 causes pancreatic β-cell failure and diabetes in mice and humans. We suggest that co-chaperone-controlled gating of the Sec61 channel by BiP is particularly important for cells, which are highly active in protein secretion, and that breakdown of this regulatory mechanism can cause apoptosis and disease.

Site-resolved imaging of fermionic ^{6}Li in an optical lattice

We demonstrate site-resolved imaging of individual fermionic ^{6}Li atoms in a single layer of a 3D optical lattice. To preserve the density distribution during fluorescence imaging, we simultaneously cool the atoms with 3D Raman sideband cooling. This laser cooling technique, demonstrated here for the first time for ^{6}Li atoms, also provides a pathway to rapid low-entropy filling of an optical lattice. We are able to determine the occupation of individual lattice sites with a fidelity >95%, enabling direct, local measurement of particle correlations in Fermi lattice systems. This ability will be instrumental for creating and investigating low-temperature phases of the Fermi-Hubbard model, including antiferromagnets and d-wave superfluidity.

Stringent adherence to a cytomegalovirus-prevention protocol is associated with reduced overall costs in the first 6 months after kidney transplantation

BACKGROUND

We previously documented that a stringent implementation of a preemptive cytomegalovirus (CMV) prevention protocol reduced the number of CMV disease episodes after kidney transplantation, when compared with a routine preemptive protocol. The impact on overall costs was assessed.

METHODS

Cost comparisons were made for inpatient and outpatient costs and overall costs, using costs provided by the financial department. Variables were analyzed using the Wilcoxon rank-sum test. A multivariable global linear model evaluated the effect of all co-variables on cost differences. In Cohort 1 (n = 84), 74% were followed with a standard CMV preemptive protocol, and 26% received prophylaxis. In Cohort 2 (n = 74), an intensified CMV surveillance protocol was applied in 74% of patients, and 26% were given prophylaxis.

RESULTS

Overall, Cohort 1 had significantly higher treatment costs as compared with Cohort 2 (mean Swiss francs [CHF] 104,548 and CHF 76,983, respectively, P = 0.0005). Excluding patients who received prophylaxis reduced these costs to CHF 89,318 in Cohort 1 and CHF 73,652 in Cohort 2. Outcome between Cohort 1 and 2 was comparable.

CONCLUSION

A stringent adherence to the CMV prevention protocol was associated with a significant reduction in overall costs. Whether this benefit is because of the demonstrated reduction in the rate of CMV disease needs to be assessed in a randomized trial.

Single-mode master-oscillator power amplifier at 647 nm with more than 500 mW output power

Using an AlGaInP-based truncated tapered power amplifier, it was possible to boost the output power of a 647-nm distributed Bragg reflector laser from 50 mW to more than 500 mW. The light source has the potential to replace bulky Kr ion lasers still in use at this wavelength.

Strongly correlated quantum walks in optical lattices

Full control over the dynamics of interacting, indistinguishable quantum particles is an important prerequisite for the experimental study of strongly correlated quantum matter and the implementation of high-fidelity quantum information processing. We demonstrate such control over the quantum walk-the quantum mechanical analog of the classical random walk-in the regime where dynamics are dominated by interparticle interactions. Using interacting bosonic atoms in an optical lattice, we directly observed fundamental effects such as the emergence of correlations in two-particle quantum walks, as well as strongly correlated Bloch oscillations in tilted optical lattices. Our approach can be scaled to larger systems, greatly extending the class of problems accessible via quantum walks.