Robust Free-Space Optical Communication Utilizing Polarization for the Advancement of Quantum Communication.

Free-space optical (FSO) communication can be subject to various types of distortion and loss as the signal propagates through non-uniform media. In experiment and simulation, we demonstrate that the state of polarization and degree of polarization of light passed though underwater bubbles, causing turbulence, is preserved. Our experimental setup serves as an efficient, low cost alternative approach to long distance atmospheric or underwater testing. We compare our experimental results with those of simulations, in which we model underwater bubbles, and separately, atmospheric turbulence. Our findings suggest potential improvements in polarization based FSO communication schemes.

Health-related quality of life after 12 months post discharge in patients hospitalised with COVID-19-related severe acute respiratory infection (SARI): a prospective analysis of SF-36 data and correlation with retrospective admission data on age, disease severity, and frailty.

Long-term outcome and 'health-related quality of life' (HRQoL) following hospitalisation for COVID-19-related severe acute respiratory infection (SARI) is limited. OBJECTIVE: To assess the impact of HRQoL in patients hospitalised with COVID-19-related SARI at 1 year post discharge, focusing on the potential impact of age, frailty, and disease severity. METHOD: Routinely collected outcome data on 1207 patients admitted with confirmed COVID-19 related SARI across all three secondary care sites in our NHS trust over 3 months were assessed in this retrospective cohort study. Of those surviving 1 year, we prospectively collected 36-item short form (SF-36) HRQoL questionnaires, comparing three age groups (<49, 49-69, and the over 69-year-olds), the relative impact of frailty (using the Clinical Frailty Score; CFS), and disease severity (using National Early Warning Score; NEWS) on HRQoL domains. RESULTS: Overall mortality was 46.5% in admitted patients. In our SF-36 cohort (n=169), there was a significant reduction in all HRQoL domains versus normative data; the most significant reductions were in the physical component (p<0.001) across all ages and the emotional component (p<0.01) in the 49-69 year age group, with age having no additional impact on HRQoL. However, there was a significant correlation between physical well-being versus CFS (the correlation coefficient=-0.37, p<0.05), though not NEWS, with no gender difference observed. CONCLUSION: There was a significant reduction in all SF-36 domains at 1 year. Poor CFS at admission was associated with a significant and prolonged impact on physical parameters at 1 year. Age had little impact on the severity of HRQoL, except in the domains of physical functioning and the overall physical component.

Intraosseous mucoepidermoid carcinoma of mandible: a rare case presentation and literature review.

Intraosseous mucoepidermoid carcinoma (IMC) is an atypical salivary gland neoplasm commonly seen in middle-aged adults. Their presentation in young individuals below the age group of 20 years is sporadic. Treatment modality mainly includes radical surgical resection for malignant tumours. There were only 13 reported cases of IMC of mandible below the age of 20 years in the English literature. All the reported cases were only managed with wide resection and radiotherapy. Surgical resection leads to loss of form and function in the young population, decreasing their morale. Hence, reconstruction should be mandated in young individuals for restoring function and aesthetics. We present a case of IMC of the mandible in a young female individual resected and reconstructed with a free fibula bone graft. Satisfactory healing is elicited with no recurrence at the 2-year follow-up period.

Superficial Cervical Plexus Block in Selective Cases of Oral and Maxillofacial Surgery as an Alternative to General Anesthesia: A Case Presentation.

The superficial cervical plexus block (SCPB) is well acknowledged, accepted for regional anesthetic for the submandibular area, neck region, and ear lobe. It is a possible valuable anesthetic technique in individuals to be operated on with conditions such as ear lobe lacerations, submandibular abscesses, and trauma to the mandibular or the neck region. Its application in oral and maxillofacial surgery is for various surgical procedures in the peri-mandibular area, excision of superficial lesions in the mandibular, ear lobe, neck region, and suturing of the skin in the corresponding region. We illustrate a case of non-union of mandibular fracture operated under superficial cervical plexus block without any complications.

Extracapsular Dissection for Small Benign Tumors of Parotid Gland: A Case Report on Contemporary Technique.

Salivary gland tumor looms as painless enlarging mass which may embrace in both major or minor glands. Pleomorphic adenoma (PA) accord about 40-70% of all salivary gland tumors, where Warthin tumor, basal cell adenoma (BCA), adenoid cystic carcinoma (ACC), and sebaceous tumors have a strong predilection for major salivary gland. However, polymorphous low-grade adenocarcinoma (PLGA) has a marked predilection for the minor salivary gland. We present a case of PA in a 26-year-old male patient that has been successfully managed by extracapsular dissection (ECD) without any post-operative complications.

Robust polarimetry via convex optimization.

We present mathematical methods, based on convex optimization, for correcting non-physical coherency matrices measured in polarimetry. We also develop the method for recovering the coherency matrices corresponding to the smallest and largest values of the degree of polarization given the experimental data and a specified tolerance. We use experimental non-physical results obtained with the standard polarimetry scheme and a commercial polarimeter to illustrate these methods. Our techniques are applied in post-processing, which complements other experimental methods for robust polarimetry.

Watt-level, ultrafast, tunable yellow source based on single-pass, fourth-harmonic generation of Cr2+:ZnS laser at 2360 nm.

We report a compact source of high power, tunable, ultrafast yellow radiation using fourth-harmonic generation of a mid-IR laser in two-stage frequency-doubling processes. Using Cr2+:ZnS laser at 2360 nm frequency-doubled in a multi-grating MgO:PPLN crystal, we have generated near-IR radiation tunable across 1137-1200 nm with average output power as high as 2.4 W and pulse width of ∼60fs. Subsequently, the near-IR radiation is frequency-doubled using a bismuth triborate (BIBO) crystal to produce coherent yellow radiation tunable across 570-596 nm with a maximum average power of ∼1W. The source has a maximum mid-IR to yellow (near-IR to yellow) single-pass conversion efficiency as high as ∼29.4% (∼47%). Without any pulse compression, the yellow source has output pulses at a repetition rate of 80 MHz with a pulse width of ∼130fs in Gaussian-shaped and a spectral width of ∼4nm corresponding to a time-bandwidth product of 0.45. The generated output beam has a Gaussian transverse beam profile with measured M2 values of Mx2∼1.07 andMy2∼1.01.