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

Optimisation of methods for the differentiation of human embryonic stem cells into retinal progenitor cells

Many ocular diseases result in visual impairment often leading to blindness with disease progression, one such example is Retinitis pigmentosa (RP). The underlying cause for blindness is often due to the degeneration of photoreceptors and supporting cells in the retina. Photoreceptors are responsible for the conversion of light signals into electrical impulses which are processed by the brain to form a visual image. Unlike other cells, photoreceptors cannot be regenerated by the body. For this reason current treatment for many ocular diseases aims to preserve what little vision patients hold. The only way such diseases could be cured is by regenerating photoreceptors and transplanting them into patients to replace lost cells and function. The differentiation of retinal cells from human embryonic stem cells (hESCs) is a difficult process. Current strategies produce low efficiencies of retinal cells which could not supply cells in a clinical environment. It is evident that the key lies within the tight control of the microenvironment of these cells at various stages of the differentiation process. In this study various optimisation avenues were investigated in order to increase the yield of retinal cells. By investigating the impact of various dissociation reagents and enzymes it was found that, the dissociation of cells using TrypLE Express significantly increased retinal gene expression. Using this reagent resulted in over a 100 fold increase in expression of photoreceptor precursor marker Nrl in comparison to the mechanical dissection with Collagenase IV (the control). In this investigation it was also found that the dissociation of cells during the process, in order to reduce cell densities is highly detrimental. The investigations were successful in finding some changes to the published protocols that optimised the differentiation process of pluripotent Shef3 hESCs into retinal cells

Nanoindentation studies on waveguides inscribed in chalcogenide glasses using ultrafast laser

Optical straight waveguides are inscribed in GeGaS and GeGaSSb glasses using a high repetition-rate sub-picosecond laser. The mechanical properties of the glasses in the inscribed regions, which have undergone photo induced changes, have been evaluated by using the nanoindentation technique. Results show that the hardness and elastic modulus of the photo-modified glasses are significantly lower as compared to the other locations in the waveguide, which tend to be similar to those of the unexposed areas. The observed mechanical effects are found to correlate well with the optical properties of the waveguides. Further, based on the results, the minimum threshold values of hardness and elastic modulus for the particular propagation mode of the waveguide (single or multi), has been established

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.

Functional outcome of nerve transfer for restoration of shoulder and elbow function in upper brachial plexus injury

<p>Abstract</p> <p>Background</p> <p>Purpose of this study was to evaluate the functional outcome of spinal accessory to suprascapular nerve transfer (XI-SSN) done for restoration of shoulder function and partial transfer of ulnar nerve to the motor branch to the biceps muscle for the recovery of elbow flexion (Oberlin transfer).</p> <p>Methods</p> <p>This is a prospective study involving 15 consecutive cases of upper plexus injury seen between January 2004 and December 2005. The average age of patients was 35.6 yrs (15–52 yrs). The injury-surgery interval was between 2–6 months. All underwent XI-SSN and Oberlin nerve transfer. The coaptation was done close to the biceps muscle to ensure early recovery. The average follow up was 15 months (range 12–36 months). The functional outcome was assessed by measuring range of movements and also on the grading scale proposed by Narakas for shoulder function and Waikakul for elbow function.</p> <p>Results</p> <p>Good/Excellent results were seen in 13/15 patients with respect to elbow function and 8/15 for shoulder function. The time required for the first sign of clinical reinnervation of biceps was 3 months 9 days (range 1 month 25 days to 4 months) and for the recovery of antigravity elbow flexion was 5 months (range 3 1/2 months to 8 months). 13 had M4 and two M3 power. On evaluating shoulder function 8/15 regained active abduction, five had M3 and three M4 shoulder abduction. The average range of abduction in these eight patients was 66 degrees (range 45–90). Eight had recovered active external rotation, average 44 degrees (range 15–95). The motor recovery of external rotation was M3 in 5 and M4 in 3. 7/15 had no active abduction/external rotation, but they felt that their shoulder was more stable. Comparable results were observed in both below and above 40 age groups and those with injury to surgery interval less than 3 or 3–6 months.</p> <p>Conclusion</p> <p>Transfer of ulnar nerve fascicle to the motor branch of biceps close to the muscle consistently results in early and good recovery of elbow flexion. Shoulder abduction and external rotation show modest but useful recovery and about half can be expected to have active movements. Two patients in early fifties also achieved good results and hence this procedure should be offered to this age group also. Surgery done earlier to 6 months gives consistently good results.</p

3-Methyl-5-(3-phenoxy­phen­yl)cyclo­hex-2-enone

In the title mol­ecule, C19H18O2, the cyclo­hexene ring adopts an envelope conformation, with all substituents equatorial. The dihedral angle between the benzene and phenyl rings is 83.75 (16)°. No classical hydrogen bonds are found in the crystal structure

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

3-Methyl-5-(4-methyl­phen­yl)cyclo­hex-2-enone

In the title mol­ecule, C14H16O, the cyclo­hexene ring adopts an envelope conformation, with all substituents equatorial. Mol­ecules are linked by C—H⋯O hydrogen bonds. A C—H⋯π inter­action involving the benzene ring is also found in the crystal structure. The H atoms of both methyl groups are disordered equally over two positions

A high gain pifa at 2.45 GHz and 5.8 GHz using wireless power transfer techniques for pacemaker application

The design of a high gain Planar Inverted F Antenna (PIFA) with two different frequencies for medical pacemaker is presented. Two PIFA designs have been optimized to be operated at ISM band of 2.45 GHz and 5.8 GHz respectively, under tolerable reflection coefficient of less than -10dB. Both of the proposed antennas are developed from copper plate with a simple structure of rectangular patch. All design and simulation has been carried out using Computer Simulation Technology (CST) Microwave Studio Suite. The simulated and measured results of the fabricated antenna on reflection coefficient, bandwidth radiation pattern, and gain are presented to validate the usefulness of the presented design. The 2D Anechoic Chamber and Agilent Technologies Network Analyzer have been used for the measurement. Both 2.45 GHz and 5.8 GHz antennas have successfully manage to achieve high gain of 6dB and 8.2dB respectively with a directional beam pattern. The presented ISM PIFAs could be potential for point-to-point communication using wireless power transfer technique for medical pacemaker application

5-(4-Chloro­phen­yl)-1-methyl-3-oxocyclo­hexa­necarbonitrile

In the title mol­ecule, C14H14ClNO, the cyclo­hexane ring adopts a chair conformation. The cyano group and the methyl group have axial and equatorial orientations, respectively. The benzene ring has an equatorial orientation. A C—H⋯π inter­action involving the benzene ring is found in the crystal structure