Quantum Chaos = Volume-Law Spatiotemporal Entanglement

Chaotic systems are highly sensitive to a small perturbation, be they biological, chemical, classical, ecological, political, or quantum. Taking this as the underlying principle, we construct an operational notion for quantum chaos. Namely, we demand that the whole future state of a large, isolated quantum system is highly sensitive to past multitime operations on a small subpart of that system. This immediately leads to a direct link between quantum chaos and volume-law spatiotemporal entanglement. Remarkably, our operational criterion already contains the routine notions, as well as the well-known diagnostics for quantum chaos. This includes the Peres-Loschmidt Echo, Dynamical Entropy, and Out-of-Time-Order Correlators. Our principle therefore unifies these existing diagnostics within a single structure. Within this framework, we also go on to quantify how several mechanisms lead to quantum chaos, such as unitary designs. Our work paves the way to systematically study exotic many-body dynamical phenomena like Many-Body Localisation, many-body scars, measurement-induced phase transitions, and Floquet dynamics. We anticipate that our work may lead to a clear link between the Eigenstate Thermalization Hypothesis and quantum chaos.Comment: 20 + 6 pages, 5 figure

Scrambling is Necessary but Not Sufficient for Chaos

We show that out-of-time-order correlators (OTOCs) constitute a probe for Local-Operator Entanglement (LOE). There is strong evidence that a volumetric growth of LOE is a faithful dynamical indicator of quantum chaos, while OTOC decay corresponds to operator scrambling, often conflated with chaos. We show that rapid OTOC decay is a necessary but not sufficient condition for linear (chaotic) growth of the LOE entropy. We analytically support our results through wide classes of local-circuit models of many-body dynamics, including both integrable and non-integrable dual-unitary circuits. We show sufficient conditions under which local dynamics leads to an equivalence of scrambling and chaos.Comment: 6+16 Pages. Comments welcom

The Fourth Branch, Separation of Powers, and Transformative Constitutionalism

66 pagesComparative constitutional law, generally, and the Global South, in particular, have witnessed two distinct and emerging movements in the past decade. The first is a proliferation of the “fourth branch” of the State. These institutions refer to those constitutionally entrenched bodies that do not fall neatly within the tripartite structure of separation of powers. They are tailor made and range from electoral to human rights commissions, tasked with securing specific constitutional norms. The second movement is “transformative constitutionalism.” Narrowly construed, transformative constitutionalism is but another interpretive tool that select constitutional courts employ. More broadly, and crucially, however, it has come to represent a constitutional vision. This vision demands a state commitment to broadscale social transformation, with substantive equality at the heart of this movement, where the constitutional machinery and its functionaries, comprising the legislature, judiciary, and executive, actively pursue a transformational “mandate.

Process Tree: Efficient Representation of Quantum Processes with Complex Long-Range Memory

We introduce a class of quantum non-Markovian processes -- dubbed process trees -- that exhibit polynomially decaying temporal correlations and memory distributed across time scales. This class of processes is described by a tensor network with tree-like geometry whose component tensors are (1) {causality-preserving} maps (superprocesses) and (2) {locality-preserving} temporal change of scale transformations. We show that the long-range correlations in this class of processes tends to originate almost entirely from memory effects, and can accommodate genuinely quantum power-law correlations in time. Importantly, this class allows efficient computation of multi-time correlation functions. To showcase the potential utility of this model-agnostic class for numerical simulation of physical models, we show how it can approximate the strong memory dynamics of the paradigmatic spin-boson model, in term of arbitrary multitime features. In contrast to an equivalently costly matrix product operator (MPO) representation, the ansatz produces a fiducial characterization of the relevant physics. Our work lays the foundation for the development of more efficient numerical techniques in the field of strongly interacting open quantum systems, as well as the theoretical development of a temporal renormalization group scheme.Comment: 19+8 pages, 10 figures, comments welcome

‘I feel weak, useless and dependent on others’ : South Asian patient experiences of haemodialysis

Shivani Sharma, Roisin Mooney, Andrew Davenport, Clara Day, Neil Duncan, David Wellsted, Maria Da Silva Gane, Kirit Modi, Ken Farrington, ‘‘I feel weak, useless and dependent on others’: South Asian patient experiences of haemodialysis’, poster presented at the Annual Conference British Renal Society, Leeds, UK, 30 June – 2 July, 2015.OBJECTIVE: Much of what is known about patient experiences of haemodialysis (HD) has been gleaned from research with White English speaking groups. People from South Asian backgrounds- originating from India, Pakistan and Bangladesh- have a three to five fold greater risk of needing treatment for renal failure. Owing to language and cultural barriers, less is known about how patients from specific ethnic minorities experience HD, although such knowledge would help shape efforts to provide suitable support. In this study, we invited those who communicate predominately or exclusively in Gujarati, Punjabi or Urdu to participate in focus groups and with the aim of exploring thoughts and feelings related to HD and its impact on day-to-day life. METHOD: Seven focus groups were held and across four NHS Trusts with high representation of patients from South Asian backgrounds. They were facilitated by a team of bilingual researchers with experience of working in healthcare contexts. Twenty-eight patients participated (15 males and 13 females; mean age 57.4 years). Focus groups were transcribed verbatim and translated into English, paying attention to retaining meaning as opposed to literal interpretation. Thematic Analysis was used to elucidate emerging themes, and using NVivo 10- a software programme designed to aid robust analysis of qualitative data. RESULTS: Patients reported numerous aspects of the ‘imposition of treatment’ that altered their sense of self and left them feeling as though they were ‘living in limbo’. Various ‘support mechanisms’ were seen as crucial in helping maintain some form of normality and these were both internally and externally derived. Hope for optimising outcomes was constrained by awareness of cultural barriers to ‘access to transplantation’ with patients’ conscious that their current situation added to ‘family stress’. Furthermore, perceptions of the ‘patient-clinician relationship’ often compounded the overall experience of HD- leaving the majority feeling trapped by their situation. CONCLUSION: Our findings highlight communalities in patient experiences of HD across different ethnic and cultural groups- delineating the aspects of treatment that patients struggle to contend with. Unique to our sample, we also expose concerns about access to kidney transplantation, with cultural factors limiting hope for improving quality of life. Targeted organ donation campaigns have a role to play here in furthering patient optimism for the future. It is apparent that patients require support in managing their altered sense of self and this can be facilitated in many ways including strengthening personal resources for coping alongside peer support.Peer reviewe

Trial protocol OPPTIMUM : does progesterone prophylaxis for the prevention of preterm labour improve outcome?

Background Preterm birth is a global problem, with a prevalence of 8 to 12% depending on location. Several large trials and systematic reviews have shown progestogens to be effective in preventing or delaying preterm birth in selected high risk women with a singleton pregnancy (including those with a short cervix or previous preterm birth). Although an improvement in short term neonatal outcomes has been shown in some trials these have not consistently been confirmed in meta-analyses. Additionally data on longer term outcomes is limited to a single trial where no difference in outcomes was demonstrated at four years of age of the child, despite those in the “progesterone” group having a lower incidence of preterm birth. Methods/Design The OPPTIMUM study is a double blind randomized placebo controlled trial to determine whether progesterone prophylaxis to prevent preterm birth has long term neonatal or infant benefit. Specifically it will study whether, in women with singleton pregnancy and at high risk of preterm labour, prophylactic vaginal natural progesterone, 200 mg daily from 22 – 34 weeks gestation, compared to placebo, improves obstetric outcome by lengthening pregnancy thus reducing the incidence of preterm delivery (before 34 weeks), improves neonatal outcome by reducing a composite of death and major morbidity, and leads to improved childhood cognitive and neurosensory outcomes at two years of age. Recruitment began in 2009 and is scheduled to close in Spring 2013. As of May 2012, over 800 women had been randomized in 60 sites. Discussion OPPTIMUM will provide further evidence on the effectiveness of vaginal progesterone for prevention of preterm birth and improvement of neonatal outcomes in selected groups of women with singleton pregnancy at high risk of preterm birth. Additionally it will determine whether any reduction in the incidence of preterm birth is accompanied by improved childhood outcome

Adjuvant enzalutamide for the treatment of early-stage androgen-receptor positive, triple-negative breast cancer: a feasibility study.

PURPOSE: Chemotherapy with or without immunotherapy remains the mainstay of treatment for triple-negative breast cancer (TNBC). A subset of TNBCs express the androgen receptor (AR), representing a potential new therapeutic target. This study assessed the feasibility of adjuvant enzalutamide, an AR antagonist, in early-stage, AR-positive (AR +) TNBC. METHODS: This study was a single-arm, open-label, multicenter trial in which patients with stage I-III, AR ≥ 1% TNBC who had completed standard-of-care therapy were treated with enzalutamide 160 mg/day orally for 1 year. The primary objective of this study was to evaluate the feasibility of 1 year of adjuvant enzalutamide, defined as the treatment discontinuation rate of enzalutamide due to toxicity, withdrawal of consent, or other events related to tolerability. Secondary endpoints included disease-free survival (DFS), overall survival (OS), safety, and genomic features of recurrent tumors. RESULTS: Fifty patients were enrolled in this study. Thirty-five patients completed 1 year of therapy, thereby meeting the prespecified trial endpoint for feasibility. Thirty-two patients elected to continue with an optional second year of treatment. Grade ≥ 3 treatment-related adverse events were uncommon. The 1-year, 2-year, and 3-year DFS were 94%, 92% , and 80%, respectively. Median OS has not been reached. CONCLUSION: This clinical trial demonstrates that adjuvant enzalutamide is a feasible and well-tolerated regimen in patients with an early-stage AR + TNBC. Randomized trials in the metastatic setting may inform patient selection through biomarker development; longer follow-up is needed to determine the effect of anti-androgens on DFS and OS in this patient population

A genome-wide association study identifies protein quantitative trait loci (pQTLs)

There is considerable evidence that human genetic variation influences gene expression. Genome-wide studies have revealed that mRNA levels are associated with genetic variation in or close to the gene coding for those mRNA transcripts - cis effects, and elsewhere in the genome - trans effects. The role of genetic variation in determining protein levels has not been systematically assessed. Using a genome-wide association approach we show that common genetic variation influences levels of clinically relevant proteins in human serum and plasma. We evaluated the role of 496,032 polymorphisms on levels of 42 proteins measured in 1200 fasting individuals from the population based InCHIANTI study. Proteins included insulin, several interleukins, adipokines, chemokines, and liver function markers that are implicated in many common diseases including metabolic, inflammatory, and infectious conditions. We identified eight Cis effects, including variants in or near the IL6R (p = 1.8×10 -57), CCL4L1 (p = 3.9×10-21), IL18 (p = 6.8×10-13), LPA (p = 4.4×10-10), GGT1 (p = 1.5×10-7), SHBG (p = 3.1×10-7), CRP (p = 6.4×10-6) and IL1RN (p = 7.3×10-6) genes, all associated with their respective protein products with effect sizes ranging from 0.19 to 0.69 standard deviations per allele. Mechanisms implicated include altered rates of cleavage of bound to unbound soluble receptor (IL6R), altered secretion rates of different sized proteins (LPA), variation in gene copy number (CCL4L1) and altered transcription (GGT1). We identified one novel trans effect that was an association between ABO blood group and tumour necrosis factor alpha (TNF-alpha) levels (p = 6.8×10-40), but this finding was not present when TNF-alpha was measured using a different assay , or in a second study, suggesting an assay-specific association. Our results show that protein levels share some of the features of the genetics of gene expression. These include the presence of strong genetic effects in cis locations. The identification of protein quantitative trait loci (pQTLs) may be a powerful complementary method of improving our understanding of disease pathways. © 2008 Melzer et al

Exploring reasons for state-level variation in incidence of dialysis-requiring acute kidney injury (AKI-D) in the United States

Background: There is considerable state-level variation in the incidence of dialysis-requiring acute kidney injury (AKI-D). However, little is known about reasons for this geographic variation. Methods: National cross-sectional state-level ecological study based on State Inpatient Databases (SID) and the Behavioral Risk Factor Surveillance System (BRFSS) in 2011. We analyzed 18 states and six chronic health conditions (diabetes mellitus [diabetes], hypertension, chronic kidney disease [CKD], arteriosclerotic heart disease [ASHD], cancer (excluding skin cancer), and chronic obstructive pulmonary disease [COPD]). Associations between each of the chronic health conditions and AKI-D incidence was assessed using Pearson correlation and multiple regression adjusting for mean age, the proportion of males, and the proportion of non-Hispanic whites in each state. Results: The state-level AKI-D incidence ranged from 190 to 1139 per million population. State-level differences in rates of hospitalization with chronic health conditions (mostly \u3c 3-fold difference in range) were larger than the state-level differences in prevalence for each chronic health condition (mostly \u3c 2.5-fold difference in range). A significant correlation was shown between AKI-D incidence and prevalence of diabetes, ASHD, and COPD, as well as between AKI-D incidence and rate of hospitalization with hypertension. In regression models, after adjusting for age, sex, and race, AKI-D incidence was associated with prevalence of and rates of hospitalization with five chronic health conditions - diabetes, hypertension, CKD, ASHD and COPD - and rates of hospitalization with cancer. Conclusions: Results from this ecological analysis suggest that state-level variation in AKI-D incidence may be influenced by state-level variations in prevalence of and rates of hospitalization with several chronic health conditions. For most of the explored chronic conditions, AKI-D correlated stronger with rates of hospitalizations with the health conditions rather than with their prevalences, suggesting that better disease management strategies that prevent hospitalizations may translate into lower incidence of AKI-D