Absorption and emission cross-sections, Stark energy levels, and temperature dependent gain of Yb:QX phosphate glass.

We have obtained the absolute absorption cross-sections of Yb-doped phosphate QX laser glass at 300 K from 800-1100 nm, and generated the emission cross-sections via the standard method of reciprocity. By generating nine detailed high-confidence fitting functions for the absorption cross-sections, we then applied reciprocity to the individual absorption functions and obtain, for the first time to our knowledge, nine corresponding detailed emission functions that when summed, display a more accurate representation of the emission cross-sections as a function of wavelength than the standard method. A deeper mathematical understanding of reciprocity is also presented, along with derived Yb:QX Stark levels.

Quality metrics for the evaluation of Rapid Response Systems: Proceedings from the third international consensus conference on Rapid Response Systems.

BACKGROUND: Clinically significant deterioration of patients admitted to general wards is a recognized complication of hospital care. Rapid Response Systems (RRS) aim to reduce the number of avoidable adverse events. The authors aimed to develop a core quality metric for the evaluation of RRS. METHODS: We conducted an international consensus process. Participants included patients, carers, clinicians, research scientists, and members of the International Society for Rapid Response Systems with representatives from Europe, Australia, Africa, Asia and the US. Scoping reviews of the literature identified potential metrics. We used a modified Delphi methodology to arrive at a list of candidate indicators that were reviewed for feasibility and applicability across a broad range of healthcare systems including low and middle-income countries. The writing group refined recommendations and further characterized measurement tools. RESULTS: Consensus emerged that core outcomes for reporting for quality improvement should include ten metrics related to structure, process and outcome for RRS with outcomes following the domains of the quadruple aim. The conference recommended that hospitals should collect data on cardiac arrests and their potential predictability, timeliness of escalation, critical care interventions and presence of written treatment goals for patients remaining on general wards. Unit level reporting should include the presence of patient activated rapid response and metrics of organizational culture. We suggest two exploratory cost metrics to underpin urgently needed research in this area. CONCLUSION: A consensus process was used to develop ten metrics for better understanding the course and care of deteriorating ward patients. Others are proposed for further development.

A novel multimodality endoscopic device for colonic submucosal dissection using a combination of bipolar radiofrequency and microwave modalities.

BACKGROUND AND STUDY AIMS: Current submucosal dissection devices are technically challenging to use, resulting in long and sometimes incomplete colonic polyp resections. The aim of this feasibility preclinical study was to evaluate a new, multimodality instrument with novel electrocautery properties. METHODS: Six female adult pigs underwent colonic submucosal resections. The novel device was used to cut mucosa and submucosa using bipolar radiofrequency (BRF; at 400 KHz), provide hemostasis with microwave coagulation (MWC; at 5.8 GHz), and inject fluid via a retractable needle. The main outcomes measured were safety (histological analysis post-recovery), performance, and time needed to achieve complete resection. RESULTS: A total of 12 consecutive colonic pseudopolyps were completely excised (two per subject) using BRF cutting. The median time to complete resection was 44.3 minutes (SD 8.9). The median defect size was 32.8 mm (SD 4.3). MWC was applied on 37 occasions for pre-coagulation or treatment of bleeding vessels. One microperforation was treated successfully with endoscopic clips. All animals recovered uneventfully during the 28-day survival period. Histology confirmed adequate healing in all postmortem defects. CONCLUSIONS: In this preclinical evaluation, the novel multimodality endoscopic device facilitated rapid and safe en bloc resection of colonic pseudopolyps.

Interesting case of subependymoma of the spinal cord.

BACKGROUND CONTEXT: Subependymomas are rare, slow-growing, and usually noninvasive/nonaggressive World Health Organization Grade I tumors that tend to occur in the ventricles. Their most common site of occurrence is the fourth ventricle followed by the lateral ventricles. Spinal cord subependymomas typically manifest as cervical and cervicothoracic intramedullary or, rarely, extramedullary mass lesions. They often present clinically with pain and neurologic symptoms, including motor, sensory, urinary, and sexual dysfunction. Histologically, there are hypocellular areas with occasional clusters of cells and frequent microcystic changes, calcifications, and hemorrhage. Radiologically, subependymomas generally manifest as eccentric well circumscribed nodular lesions with mild-to-moderate enhancement. PURPOSE: To highlight an interesting and rare presentation for subependymoma of the spinal cord. STUDY DESIGN: This is a case report of a single patient in whom a subependymoma was resected from the cervical spinal cord with return to normal functioning. METHODS: Clinical examination, magetic resonance imaging evaluation, surgical resection, and histological analysis were performed for diagnosis and treatment of this patient. RESULTS: The patient experiencing myelopathy symptoms underwent a surgical resection of cervical spinal cord subependymoma that resulted in return to normal function. CONCLUSIONS: Subependymoma should be included in the differential diagnosis of atypical presentations for myelopathy, as discrete surgical resection can result in good outcome.

Microwave ablation of ex vivo human liver and colorectal liver metastases with a novel 14.5 GHz generator.

PURPOSE: This study assessed the relationship between time, power and ablation size using a novel high-frequency 14.5 GHz microwave applicator in ex vivo human hepatic parenchyma and colorectal liver metastases. Previous examination has demonstrated structurally normal but non-viable cells within the ablation zone. This study aimed to further investigate how ablation affects these cells, and to confirm non-viability. MATERIALS AND METHODS: Ablations were performed in ex vivo human hepatic parenchyma and tumour for a variety of time (10-180 s) and power (10-50 W) settings. Histological examination was performed to assess cellular anatomy, whilst enzyme histochemistry was used to confirm cellular non-viability. Transmission electron microscopy was used to investigate the subcellular structural effects of ablation within these fixed cells. Preliminary proteomic analysis was also performed to explore the mechanism of microwave cell death. RESULTS: Increasing time and power settings led to a predictable and reproducible increase in size of ablation. At 50 W and 180 s application, a maximum ablation diameter of 38.8 mm (±1.3) was produced. Ablations were produced rapidly, and at all time and power settings ablations remained spherical (longest:shortest diameter <1.2). Routine histological analysis using haematoxylin-eosin (H&E) confirmed well preserved cellular anatomy despite ablation. Transmission electron microscopy demonstrated marked subcellular damage. Enzyme histochemistry showed complete absence of viability in ablated tissue. CONCLUSIONS: Large spherical ablation zones can be rapidly and reproducibly achieved in ex vivo human hepatic parenchyma and colorectal liver metastases using a 14.5 GHz microwave generator. Despite well preserved cellular appearance, ablated tissue is non-viable.

Flexor femoris muscle complex: grading systems used to describe the complete spectrum of injury.

The flexor femoris muscle complex (FFMC) is also known as the hamstring muscle complex or commonly as the "hamstrings." Three muscles comprise this group: the biceps femoris, the semitendinosus, and semimembranosus. The FFMC is one of the most frequent sites of muscle injury. Hamstring injuries are becoming more common secondary to the increase in society's pursuit of high-energy athletic activities and the greater mobility of our active seniors. The biceps femoris is the most commonly injured muscle of the FFMC.