Optical vortex generation from molecular chromophore arrays

The generation of light endowed with orbital angular momentum, frequently termed optical vortex light, is commonly achieved by passing a conventional beam through suitably constructed optical elements. This Letter shows that the necessary phase structure for vortex propagation can be directly produced through the creation of twisted light from the vacuum. The mechanism is based on optical emission from a family of chromophore nanoarrays that satisfy specific geometric and symmetry constraints. Each such array can support pairs of electronically delocalized doubly degenerate excitons whose azimuthal phase progression is responsible for the helical wave front of the emitted radiation. The exciton symmetry dictates the maximum magnitude of topological charge; detailed analysis secures the conditions necessary to deliver optical vortices of arbitrary order

Integration and Characterisation of Piezoelectric Macro-Fibre Composite on Carbon Fibre Composite for Vibration Energy Harvesting

Carbon fibre composite is a strong and a lightweight structural material with applications in automotive, aerospace, medical and industrial applications. The integration of piezoelectric transducer films onto the composite stack can add vibration energy harvesting capabilities to enable net-zero-power autonomous sensing for an otherwise purely mechanical structure. A PZT macro-fibre composite is co-cured with a carbon/epoxy pre-preg in order to manufacture the multi-functional composite plate. Without noticeably increasing profile, adding weight or compromising mechanical integrity, the resultant mechanical plate can recover power from vibrational excitations. With a volume of 13.5cm3, a peak average power of 9.25mW was recorded at 2.66 ms−2. The normalised power density of 97 μW cm −3 m −2 s 4 is comparable to some of the state-of-the-art PZT generators reported in the literature

Confining Flux Tubes in a Current Algebra Approach

We describe flux tubes and their interactions in a low energy sigma model induced by $SU({N_f}) \rightarrow SO({N_f})$ flavor symmetry breaking in $SO(N_c)$ QCD. Unlike standard QCD, this model allows gauge confinement to manifest itself in the low energy theory, which has unscreened spinor color sources and global $Z_2$ flux tubes. We construct the flux tubes and show how they mediate the confinement of spinor sources. We further examine the flux tubes' quantum stability, spectrum and interactions. We find that flux tubes are Alice strings, despite ambiguities in defining parallel transport. Furthermore, twisted loops of flux tube support skyrmion number, just as gauged Alice strings form loops that support monopole charge. This model, while phenomenologically nonviable, thus affords a perspective on both the dynamics of confinement and on subtleties which arise for global Alice strings.Comment: 29 pages (REVTEX) plus 6 figures, two corrections in the final section and added reference

Heterotic String Field Theory

We construct the Neveu-Schwarz sector of heterotic string field theory using the large Hilbert space of the superghosts and the multi-string products of bosonic closed string field theory. No picture-changing operators are required as in Wess-Zumino-Witten-like open superstring field theory. The action exhibits a novel kind of nonpolynomiality: in addition to terms necessary to cover missing regions of moduli spaces, new terms arise from the boundary of the missing regions and its subspaces. We determine the action up to quintic order and a subset of terms to all orders.Comment: 15 pages, no figures, LaTeX2e; v2: minor cosmetic change

Pengaruh Perubahan Iklim Terhadap Kedalaman dan Intensitas Hujan

Climate change is a natural phenomenon where there is a very extreme change in the value of climatological elements. The increase in floods and droughts is caused by changes in the characteristics of rain that are far below normal. This study aims to determine the trend of climate change resulting in changes in the characteristics of rain, namely the depth and intensity of rain. Assessment of climate change is seen from trend graphs and the Mann-Kendall statistical test to determine significant changes. To determine the effect of climate change on the characteristics, of rainfall, the calculation is divided into 3 periods, namely period 1 (1994-2003), period 2 (2004-2014), and period 3 (2014-2018). Based on the Mann-Kendall statistical test, climate change also occurred as indicated by a significant Z value, namely the Kediri and Sopak climatological stations 4.64 and 6.26, respectively. The pattern of changes in the daily average rain depth and intensity has occurred from 1994 – 2018 where in period 1 in 1994-2003 there was a normal trend, in period 2 in 2004-2013 there was an increasing trend and in period 3 in 2014-2018, there was an extreme increasing tren

Awareness of the Importance of and Adherence to Patients’ Rights Among Physicians and Nurses in Oman: An analytical cross-sectional study across different levels of healthcare

Objectives: This study aimed to determine the extent to which physicians and nurses in Oman were aware of the importance of and adhere to patients’ rights and whether this differed according to role, nationality, position and institutional healthcare level. Methods: This analytical cross-sectional study was carried out between December 2015 and March 2016 at various governmental healthcare institutions in Oman. A self-administered questionnaire was distributed to 1,385 practitioners at all healthcare levels. Results: A total of 1,213 healthcare practitioners (response rate: 87.58%) completed the survey, of which 685 (56.47%) were nurses and 528 (43.53%) were physicians. Overall, awareness of the importance of patients’ rights was high (91.51%), although adherence to these rights in practice was low (63.81%). The right of the patient to be informed was considered least important and was least adhered to (81.2% and 56.39%). Nationality, role and institutional level were significantly associated with awareness (P = 0.002, 0.024 and 0.034, respectively). Non-Omani staff were significantly more likely than Omani staff to be aware of (odds ratio [OR] = 1.696; P = 0.032) and adhere to (OR = 2.769; P <0.001) patient rights. Furthermore, tertiary care staff were twice as likely as primary care staff to perceive the importance of patient rights (OR = 2.076; P = 0.019). While physicians were more likely than nurses to be aware of the importance of patient rights, this difference was not significant (OR = 1.516; P = 0.126). Conclusion: These findings may help inform measures to enhance awareness of and adherence to patients’ rights in Oman.Keywords: Medical Ethics; Patient Rights; Awareness; Adherence; Physicians; Nurses; Oman