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Objective: The COVID-19 pandemic declared in early 2020 led to the closure of Australia's international borders and the stranding of thousands of Australians overseas. We surveyed "stranded" Australians pre- and post-repatriation to evaluate their stress-coping responses at the time and the longer-term impacts of their experience. Method: Stranded Australians (n = 587; 18–70 years of age; M = 40.15, SD = 11.90) completed a survey measuring COVID-19 impact, stressor appraisal and coping strategy, and psychological adjustment, and 203 of them completed a follow-up survey of psychological adjustment and posttraumatic stress disorder (PTSD) symptoms post-repatriation. Results: Path analysis showed that "primary" appraisals of the repatriation situation (i.e. as a threat or challenge) were positively associated with negative affect, use of avoidant coping, and poorer psychological adjustment. Although the follow-up survey revealed improvements in psychological adjustment, initial use of avoidant coping was associated with higher levels of PTSD post-repatriation. Conclusion: Primary appraisals and avoidant coping were associated with poorer psychological adjustment and longer-term PTSD symptomatology. The results highlight the need for ongoing mental health support for repatriated Australians and call for higher prioritisation of practical and mental health support in the event of future border closures. KEY POINTS: What is already known about this topic: Australians were stranded overseas in large numbers during the COVID-19 pandemic due to a combination of border closures, restrictions on travel, and limited availability of repatriation flights. "Stranded" Australians received limited practical, informational, and health-related support from the Australian Government while awaiting repatriation. Little is known about the stressors faced by stranded Australians, the psychological impact of these stressors, the coping strategies they employed at the time, and the longer-term relevance of these strategies for their psychological functioning upon returning to Australia. What this topic adds: Results showed that over a third of stranded Australians reported "severe" to "extreme" levels of psychological adjustment problems both pre and post repatriation. Worse outcomes were seen in stranded Australians who appraised their repatriation situation as a threat or challenge and who engaged in avoidant coping in response. The results highlight the need for ongoing mental health support for repatriated Australians and call for higher prioritisation of practical and mental health support in the event of future border closures. [ABSTRACT FROM AUTHOR]

The chorioallantoic membrane of oviparous reptiles forms a vascular interface with the eggshell. The eggshell contains calcium, primarily as calcium carbonate. Extraction and mobilization of this calcium by the chorioallantoic membrane contributes importantly to embryonic nutrition. Development of the chorioallantoic membrane is primarily known from studies of squamates and birds. Although there are pronounced differences in eggshell structure, squamate and bird embryos each mobilize calcium from eggshells. Specialized cells in the chicken chorionic epithelium transport calcium from the eggshell aided by a second population of cells that secrete protons generated by the enzyme carbonic anhydrase. Calcium transporting cells also are present in the chorioallantoic membrane of corn snakes, although these cells function differently than those of chickens. We used histology and immunohistology to characterize the morphology and functional attributes of the chorioallantoic membrane of corn snakes. We identified two populations of cells in the outer layer of the chorionic epithelium. Calbindin‐D28K, a cellular marker for calcium transport expressed in squamate chorioallantoic membranes, is localized in large, flattened cells that predominate in the chorionic epithelium. Smaller cells, interspersed among the large cells, express carbonic anhydrase 2, an enzyme not previously localized in the chorionic epithelium of an oviparous squamate. These findings indicate that differentiation of chorionic epithelial cells contributes to extraction and transport of calcium from the eggshell. The presence of specializations of chorioallantoic membranes for calcium uptake from eggshells in chickens and corn snakes suggests that eggshell calcium was a source of embryonic nutrition early in the evolution of Sauropsida. RESEARCH HIGHLIGHTS: The outer epithelium of the chorioallantoic membrane of oviparous corn snakes is differentiated into two distinct populations of cells. Small secretory cells promote calcium erosion from the eggshell; large flattened cells facilitate calcium uptake. [ABSTRACT FROM AUTHOR]

During this demonstration project, an overhead portion of a four-wire power distribution circuit was converted to a five-wire system. The fifth wire is an isolated neutral that carries all of the unbalanced return current. The measurements suggested that a ground relay could be set much lower on a five-wire system than a comparable four-wire system for improved high-impedance fault detection. Stray voltage was also much lower when the circuit was operated as a five-wire configuration. Magnetic fields were generally lower on the five-wire circuit than at the same locations during four-wire operation. Conversion of an existing four-wire system to a five-wire system presented several unique concerns including fifth-wire placement, crew safety and operations, and how to interface the five-wire system with the existing four-wire distribution system. Index Terms--Grounding, high-impedance faults, magnetic fields, power distribution, stray voltage.

Ground level electric, and more recently magnetic, fields from overhead power transmission lines are increasingly important considerations in right of way specification, with states setting or planning to set edge of right of way limits. Research has been conducted in high phase order power transmission wherein six or twelve phases are used to transmit power in less physical space and with reduced electrical environmental effects than conventional designs. The first magnetic field testing, as reported in this paper, has verified predictive methods for determination of magnetic fields from high phase order lines. Based on these analytical methods, field profiles have been determined for lines of different phase order of comparable power capacity. Potential advantages of high phase order as a means of field mitigation are discussed.

Conversion of an existing double circuit 115 kV overhead transmission line near Binghamton, New York to six-phase operation will provide a commercial demonstration of feasibility of high phase order power transmission. Analyses of insulation performance, corona and field effects, and load flow and system stability have been performed as part of the preliminary engineering for this project. This paper summarizes these studies and shows that operation at six-phase is possible with a 40% increase in phase-to-ground voltage and a doubling of surge impedance loading.

Echocardiography is a noninvasive diagnostic technique that uses ultrasound to visualize internal heart structures, allowing their measurement. Until recently, transthoracic echocardiography (TTE), in which the ultrasound probe is placed on the exterior of the chest wall, was the only significant technique in use. However, transesophageal echocardiography (TEE), in which the probe is placed inside the esophagus, has gradually gained in popularity. The two techniques have not often been rigorously compared in terms of their relative effectiveness in diagnosis and treatment. The results from TTE and TEE evaluation of 86 cases were studied. TEE solved 95 percent of diagnostic problems, whereas TTE did so for only 48 percent. Four cases that were unanswered by TEE could also not be determined by TTE. TEE was significantly more effective than TTE in diagnosing vegetations (bacterial or other growths) on the internal surface of the heart, clots in the upper heart chamber, heart masses, and aortic dissections (divisions of the aortic orifice). Patients with mitral valve constriction required both types of studies. TEE prevented the need for, or was needed as a follow-up to, a number of cardiac catheterizations and some scanning tests, while TTE obviated the need for only two catheterizations but no other scanning procedures. Catheterization was needed to make a diagnosis missed by TEE in two cases. TEE led to changes in treatment in 19 cases, 10 of which were also diagnosed by TTE. The study suggests that while TTE remains the standard echocardiographic technique, TEE is complementary to it, and the two procedures can reduce hospitalization costs and avoid patient discomfort and risk by obviating the need for additional diagnostic procedures. (Consumer Summary produced by Reliance Medical Information, Inc.)