Divergence-free approach for obtaining decompositions of quantum-optical processes

Operator-sum representations of quantum channels can be obtained by applying the channel to one subsystem of a maximally entangled state and deploying the channel-state isomorphism. However, for continuous-variable systems, such schemes contain natural divergences since the maximally entangled state is ill-defined. We introduce a method that avoids such divergences by utilizing finitely entangled (squeezed) states and then taking the limit of arbitrary large squeezing. Using this method we derive an operator-sum representation for all single-mode bosonic Gaussian channels where a unique feature is that both quantum-limited and noisy channels are treated on an equal footing. This technique facilitates a proof that the rank-one Kraus decomposition for Gaussian channels at its respective entanglement-breaking thresholds, obtained in the overcomplete coherent state basis, is unique. The methods could have applications to simulation of continuous-variable channels.Comment: 18 pages (8 + appendices), 4 figs. V2: close to published version, dropped Sec.VI of v1 to be expanded elsewher

Transesophageal Echocardiographic evaluation of Coronary Artery Disease.

INTRODUCTION : With the development of digital imaging capabilities, the emergence of multiplane TEE, and cine loop review, TEE has improved visualization of the coronary artery tree and enhanced detection of its abnormalities. Although TEE is unlikely to replace coronary angiography as the primary imaging modality in coronary artery disease, published reports over the past 12 years have defined a role for TEE in coronary artery disease. Although the diagnosis of ostial stenosis of the left main coronary artery usually is made by coronary angiography, positioning of the catheter across the obstruction may obscure this diagnosis during the contrast injection. Several authors have reported cases in which TEE was able to make a correct diagnosis in patients with possible left main coronary artery stenosis, in whom damping of the left main coronary artery wave form during catheterization did not allow differentiation of significant left main artery. The diagnosis of left main coronary artery disease is important in the management of patients with symptomatic coronary artery disease. TEE can be considered when cardiac catheterization suggests ostial stenosis but angiography is inconclusive. The diagnosis of a proximal stenosis may be confirmed by direct visualization of the area of narrowing and supported by color flow Doppler demonstration of flow aliasing. Recent advances in TEE have enabled the direct evaluation of coronary flow especially in the proximal and mid LAD where the culprit lesion of AWMI is present. TEE can potentially enable direct evaluation of coronary perfusion at a site just distal to culprit lesion in AWMI. We hypothesized that good reperfusion would be associated with less reduction in coronary flow and therefore would have better ante grade flow visualization by color TEE and less reduced ante grade flow velocity by pulsed TEE. AIM : 1. Visualization and measurement of the size of Left main coronary in patients with coronary artery disease by Transesophageal echocardiography. 2. Measurement of blood flow velocity in Left main and Proximal Left Anterior Descending artery in patients with coronary artery disease by Transesophageal echocardiography. 3. Measurement of intimal thickness and presence of plaque and its size in descending thoracic aorta in patients with coronary artery disease by Transesophageal echocardiography. CONCLUSION : 1. Transesophageal echocardiography is a promising and effective non invasive diagnostic method of visualizing and measuring the size of proximal left coronary artery in patients with coronary artery disease. 2. TEE could visualize the LM in all the patients (100%). By TEE we can visualize proximal LAD and proximal LCX in 93% and 87% respectively. 3. Patients with acute AWMI who had unsuccessful thrombolysis showed significantly low coronary blood flow velocity by TEE compared to successfully thrombolysed group who had relatively higher coronary flow. 4. Patients with LM and proximal LAD narrowing diagnosed by TEE showed angiographic correlation with coronary narrowing in CAG. 5. Descending thoracic aortic plaque was present in 76% of patients with acute AWMI. There was no statistically significant correlation between the presence of plaque and the degree of presence and severity of CAD

Factors associated with the uptake of HIV testing and treatment in the first year of the HPTN 071 (PopART) intervention

Introduction: The HPTN 071 (PopART) trial is a community randomised trial in Zambia and South Africa, examining the impact of combination prevention, including treatment as prevention using Universal Test and Treat (UTT), on community level HIV-incidence. This PhD evaluates the factors associated with uptake of the key interventions, during the first year of the trial. Methods: Two systematic reviews were conducted on home-based HIV testing and counselling (HB-HTC), and the cascade-of-care following community-based HTC, respectively. In addition, two case-control (CC) studies were nested within PopART, to examine factors associated with the uptake of the door-to-door home-based universal testing (CC study 1), and universal treatment (CC study 2) interventions. Results: Our results suggest that HB-HTC in sub-Saharan Africa is widely accepted – uptake among those offered HB-HTC was 83% in a systematic review and meta-analysis of studies (2000-2012). The second systematic review found considerable variability in measures used to report linkage-to-care and ART initiation and in outcomes reported, even for similar time periods following HIV-detection (studies between 2006-2016). CC1 found no differences between acceptors and non-acceptors of HB-HTC by demographic and behavioural characteristics. CC2 identified that the more lifetime sexual partners participants reported, the more likely they were to achieve timely linkage and ART initiation (TLA). Negative perceptions about clinic infra-structure were associated with failure to achieve TLA. Both CC studies found that favourable views about the Community HIV-care Providers was associated with uptake of interventions, while neither stigma nor unfavourable views about clinic staff were associated with uptake. Conclusion: This PhD contributes to knowledge on the cascade-of-care and UTT. It suggests that PopART interventions are acceptable across population sub-groups, providing optimism for achieving universal coverage using the PopART model to implement UTT. If individuals with high-risk sexual behaviour embrace interventions as we observed, there is great promise for treatment as prevention

Depression in patients following limb reconstructive surgeries for trauma

Background: Psychological complications are common following physical trauma and its surgical treatment. Studies on trauma patients are mostly from the Western world and have focussed more on posttraumatic stress disorder and less on depression.Methods: This study was conducted in a tertiary referral centre for trauma in South India. One hundred patients who had undergone limb reconstructive surgeries following trauma were included in the study. The major causes of trauma were occupational accidents and road traffic accidents. Beck depression inventory II was used to diagnose depression. The severity of trauma, impairment in joint motion and sensory impairment were also determined. Association between the variables was assessed using Chi -Square/ Fisher’s exact test.Results: The prevalence of depression was found to be 36% (95% CI: 26.6-45.4). Age between 41 and 60 years, unemployment, severe degree of injury, and the period between three months and one year of trauma were found to have significant association with depression.Conclusions: Depression is common following physical trauma and its surgical treatment. Its early recognition and treatment is important to ensure faster recovery and better quality of life.

Hospital-based routine HIV testing in high-income countries: a systematic literature review.

OBJECTIVES: To produce a summary of the published evidence of the barriers and facilitators for hospital-based routine HIV testing in high-income countries. METHODS: Electronic databases were searched for studies, which described the offer of HIV testing to adults attending emergency departments (EDs) and acute medical units (AMUs) in the UK and US, published between 2006 and 2015. Other high-income countries were not included, as their guidelines do not recommend routine testing for HIV. The main outcomes of interest were HIV testing uptake, HIV testing coverage, factors facilitating HIV screening and barriers to HIV testing. Fourteen studies met the pre-defined inclusion criteria and critically appraised using mixed methods appraisal tool (MMAT). RESULTS: HIV testing coverage ranged from 9.7% to 38.3% and 18.7% to 26% while uptake levels were high (70.1-84% and 53-75.4%) in the UK and US, respectively. Operational barriers such as lack of time, the need for training and concerns about giving results and follow-up of HIV positive results, were reported. Patient-specific factors including female sex, old age and low risk perception correlated with refusal of HIV testing. Factors that facilitated the offer of HIV testing were venous sampling (vs. point-of-care tests), commitment of medical staff to HIV testing policy and support from local HIV specialist providers. CONCLUSIONS: There are several barriers to routine HIV testing in EDs and AMUs. Many of these stem from staff fears about offering HIV testing due to the perceived lack of knowledge about HIV. Our systematic review highlights areas which can be targeted to increase coverage of routine HIV testing

Evaluating the Feasibility and Impact of a Well-being Retreat for Physicians and Advanced Practice Providers

Introduction: Work stress experienced by physicians and advanced practice providers (APPs) can have a detrimental psychological and physical impact. Targeted interventions that focus on self-awareness, peer connection, and intentional self-care may reduce stress and improve well-being and professional fulfillment. Methods: This is a summative program evaluation of a two-day well-being retreat for physicians and APPs employed at a healthcare system headquartered in Florida. Led by mental health professionals in May 2022, this retreat combined facilitator-led workshops and experiential practice activities with opportunities for peer connection and designated time with family members. The retreat objectives were to facilitate social support, improve knowledge in areas of self-care, and build reflection skills that lead to intentional changes in well-being. Data collection occurred immediately before and after the intervention in May 2022. Wilcoxon Signed Ranks Tests were conducted to examine pre-post differences in the outcomes of self-reflection and insight, mindful self-care, anxiety, perceived stress, and professional fulfillment. Post-program feedback was collected, synthesized, and described. Results: Twenty-one clinicians attended the retreat, and a self-selected sample of twelve attendees participated in the evaluation portion of the project. Perceived stress significantly decreased (19.00 vs. 15.92; p = 0.01), and professional fulfillment significantly improved (15.50 vs. 17.50; p = 0.04) following the retreat. Participants reported the following benefits of the retreat: a reminder to focus on self-care, motivation for healthy behavior change, and an opportunity to self-reflect. Conclusion: Findings suggest that the retreat intervention met its objectives, and there is preliminary evidence that it may be a feasible approach to improve well-being and reduce stress in physicians and APPs. While significant changes in the practice environment are necessary to address the causes and consequences of work stress, individual-level programs remain important and relevant to the protection of well-being. This project builds upon the literature about interventions with diverse modalities

Is home-based HIV testing universally acceptable? Findings from a case-control study nested within the HPTN 071 (PopART) trial.

OBJECTIVE: The HPTN 071 (PopART) trial is examining the impact of a package including universal testing and treatment on community-level HIV incidence in Zambia and South Africa. We conducted a nested case-control study to examine factors associated with acceptance of home-based HIV testing and counselling (HB-HTC) delivered by community HIV-care providers (CHiPs) in PopART intervention communities. METHODS: Of 295 447 individuals who were offered testing, random samples of individuals who declined HB-HTC (cases) and accepted HB-HTC (controls), stratified by gender and community, were selected. Odds ratios comparing cases and controls were estimated using multivariable logistic regression. RESULTS: Data from 642 participants (313 cases, 329 controls) were analysed. There were no differences between cases and controls by demographic or behavioural characteristics including age, marital or socio-economic position. Participants who felt they could be open with CHiPs (AOR: 0.46, 95% CI: 0.30-0.71, P < 0.001); self-reported as not previously tested (AOR: 0.64; 95% CI: 0.43-0.95, P = 0.03); considered HTC at home to be convenient (AOR: 0.38, 95% CI: 0.27-0.54, P = 0.001); knowing others who had accepted HB-HTC from the CHiPs (AOR: 0.49, 95% CI: 0.31-0.77, P = 0.002); or were motivated to get treatment without delay (AOR: 0.60, 95% CI: 0.43-0.85, P = 0.004) were less likely to decline the offer of HB-HCT. Those who self-reported high-risk sexual behaviour were also less likely to decline HB-HCT (AOR: 0.61, 95% CI: 0.39-0.93, P = 0.02). Having stigmatising attitudes about HB-HTC was not an important barrier to HB-HCT uptake. Men who reported fear of HIV were more likely to decline HB-HCT (AOR: 2.68, 95% CI: 1.33-5.38, P = 0.005). CONCLUSION: Acceptance of HB-HTC was associated with lack of previous HIV testing, positive attitudes about HIV services/treatment and perception of high sexual risk. Uptake of HB-HCT among those offered it was similar across a range of demographic and behavioural subgroups suggesting it was 'universally' acceptable

Blueprint for a Scalable Photonic Fault-Tolerant Quantum Computer

Photonics is the platform of choice to build a modular, easy-to-network quantum computer operating at room temperature. However, no concrete architecture has been presented so far that exploits both the advantages of qubits encoded into states of light and the modern tools for their generation. Here we propose such a design for a scalable and fault-tolerant photonic quantum computer informed by the latest developments in theory and technology. Central to our architecture is the generation and manipulation of three-dimensional hybrid resource states comprising both bosonic qubits and squeezed vacuum states. The proposal enables exploiting state-of-the-art procedures for the non-deterministic generation of bosonic qubits combined with the strengths of continuous-variable quantum computation, namely the implementation of Clifford gates using easy-to-generate squeezed states. Moreover, the architecture is based on two-dimensional integrated photonic chips used to produce a qubit cluster state in one temporal and two spatial dimensions. By reducing the experimental challenges as compared to existing architectures and by enabling room-temperature quantum computation, our design opens the door to scalable fabrication and operation, which may allow photonics to leap-frog other platforms on the path to a quantum computer with millions of qubits.Comment: 38 pages, many figures. Comments welcom

Addressing social issues in a universal HIV test and treat intervention trial (ANRS 12249 TasP) in South Africa: methods for appraisal

Background: The Universal HIV Test and Treat (UTT) strategy represents a challenge for science, but is also a challenge for individuals and societies. Are repeated offers of provider-initiated HIV testing and immediate antiretroviral therapy (ART) socially-acceptable and can these become normalized over time? Can UTT be implemented without potentially adding to individual and community stigma, or threatening individual rights? What are the social, cultural and economic implications of UTT for households and communities? And can UTT be implemented within capacity constraints and other threats to the overall provision of HIV services? The answers to these research questions will be critical for routine implementation of UTT strategies. Methods/design: A social science research programme is nested within the ANRS 12249 Treatment-as-Prevention (TasP) cluster-randomised trial in rural South Africa. The programme aims to inform understanding of the (i) social, economic and environmental factors affecting uptake of services at each step of the continuum of HIV prevention, treatment and care and (ii) the causal impacts of the TasP intervention package on social and economic factors at the individual, household, community and health system level. We describe a multidisciplinary, multi-level, mixed-method research protocol that includes individual, household, community and clinic surveys, and combines quantitative and qualitative methods. Discussion: The UTT strategy is changing the overall approach to HIV prevention, treatment and care, and substantial social consequences may be anticipated, such as changes in social representations of HIV transmission, prevention, HIV testing and ART use, as well as changes in individual perceptions and behaviours in terms of uptake and frequency of HIV testing and ART initiation at high CD4. Triangulation of social science studies within the ANRS 12249 TasP trial will provide comprehensive insights into the acceptability and feasibility of the TasP intervention package at individual, community, patient and health system level, to complement the trial's clinical and epidemiological outcomes. It will also increase understanding of the causal impacts of UTT on social and economic outcomes, which will be critical for the long-term sustainability and routine UTT implementation. Trial registration: Clinicaltrials.gov: NCT01509508; South African Trial Register: DOH-27-0512-3974

Poly(ADP-ribose) polymerase family member 14 (PARP14) is a novel effector of the JNK2-dependent pro-survival signal in multiple myeloma

Copyright @ 2013 Macmillan Publishers Limited. This is the author's accepted manuscript. The final published article is available from the link below.Regulation of cell survival is a key part of the pathogenesis of multiple myeloma (MM). Jun N-terminal kinase (JNK) signaling has been implicated in MM pathogenesis, but its function is unclear. To elucidate the role of JNK in MM, we evaluated the specific functions of the two major JNK proteins, JNK1 and JNK2. We show here that JNK2 is constitutively activated in a panel of MM cell lines and primary tumors. Using loss-of-function studies, we demonstrate that JNK2 is required for the survival of myeloma cells and constitutively suppresses JNK1-mediated apoptosis by affecting expression of poly(ADP-ribose) polymerase (PARP)14, a key regulator of B-cell survival. Strikingly, we found that PARP14 is highly expressed in myeloma plasma cells and associated with disease progression and poor survival. Overexpression of PARP14 completely rescued myeloma cells from apoptosis induced by JNK2 knockdown, indicating that PARP14 is critically involved in JNK2-dependent survival. Mechanistically, PARP14 was found to promote the survival of myeloma cells by binding and inhibiting JNK1. Moreover, inhibition of PARP14 enhances the sensitization of MM cells to anti-myeloma agents. Our findings reveal a novel regulatory pathway in myeloma cells through which JNK2 signals cell survival via PARP14, and identify PARP14 as a potential therapeutic target in myeloma.Kay Kendall Leukemia Fund, NIH, Cancer Research UK, Italian Association for Cancer Research and the Foundation for Liver Research