1,862 research outputs found

    Desorption from Hot Scandate Cathodes: Effects on Vacuum Device Interior Surfaces after Long-Term Operation

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    Scandate cathodes have exhibited superior emission properties compared to current state-of-the-art “M-type” thermionic cathodes. However, their integration into vacuum devices is limited in part by a lack of knowledge regarding their functional lifespan and behavior during operation. Here, we consider thermal desorption from scandate cathodes by examining the distribution of material deposited on interior surfaces of a sealed vacuum device after ~26,000 h of cathode operation. XPS, EDS, and TEM analyses indicate that on the order of 1 wt.% of the initial impregnate is desorbed during a cathode’s lifetime, Ca does not desorb uniformly with time, and little to no Sc desorbs from the cathode surfaces (or does so at an undetectable rate). Findings from this first-ever study of a scandate cathode after extremely long-time operation yield insight into the utility of scandate cathodes as components in vacuum devices and suggest possible effects on device performance due to deposition of desorption products on interior device surfaces

    Bilateral Brachial Plexus Home Going Catheters After Digital Amputation for Patient With Upper Extremity Digital Gangrene

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    Peripheral nerve catheter placement is used to control surgical pain. Performing bilateral brachial plexus block with catheters is not frequently performed; and in our case sending patient home with bilateral brachial plexus catheters has not been reported up to our knowledge. Our patient is a 57 years old male patient presented with bilateral upper extremity digital gangrene on digits 2 through 4 on both sides with no thumb involvement. The plan was to do the surgery under sequential axillary blocks. On the day of surgery a right axillary brachial plexus block was performed under ultrasound guidance using 20 ml of 0.75% ropivacaine. Patient was taken to the OR and the right fingers amputation was carried out under mild sedation without problems. Left axillary brachial plexus block was then done as the surgeon was closing the right side, two hours after the first block was performed. The left axillary block was done also under ultrasound using 20 ml of 2% mepivacaine. The brachial plexus blocks were performed in a sequential manner. Surgery was unremarkable, and patient was transferred to post anesthetic care unit in stable condition. Over that first postoperative night, the patient complained of severe pain at the surgical sites with minimal pain relief with parentral opioids. We placed bilateral brachial plexus catheters (right axillary and left infra-clavicular brachial plexus catheters). Ropivacaine 0.2% infusion was started at 7 ml per hour basal rate only with no boluses on each side. The patient was discharged home with the catheters in place after receiving the appropriate education. On discharge both catheters were connected to a single ON-Q (I-flow Corporation, Lake Forest, CA) ball pump with a 750 ml reservoir using a Y connection and were set to deliver a fixed rate of 7 ml for each catheter. The brachial plexus catheters were removed by the patient on day 5 after surgery without any difficulty. Patient's postoperative course was otherwise unremarkable. We concluded that home going catheters are very effective in pain control postoperatively and they shorten the period of hospital stay

    Effectiveness, acceptability and potential harms of peer support for self-harm in non-clinical settings: systematic review

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    BACKGROUND: Many people who have self-harmed prefer informal sources of support or support from those with lived experience. However, little is known about whether peer support improves outcomes for people who have self-harmed or about the risks of peer support interventions in non-clinical settings. AIMS: The aims of this review were to examine the effectiveness, acceptability and potential risks of peer support for self-harm, and how these risks might be mitigated. METHOD: We searched bibliographic databases and grey literature for papers published since 2000. We included peer support for self-harm that occurred in voluntary-sector organisations providing one-to-one or group support, or via moderated online peer support forums. RESULTS: Eight of the ten papers included focused on peer support that was delivered through online media. No study compared peer support with other treatments or a control group, so limited conclusions could be made about its effectiveness. Peer support for self-harm was found to be acceptable and was viewed as having a range of benefits including a sense of community, empowerment, and access to information and support. The most commonly perceived risk associated with peer support was the potential for triggering self-harm. CONCLUSIONS: Our findings highlighted a range of benefits of being part of a group with very specific shared experiences. Mitigations for potential risks include organisations using professional facilitators for groups, trigger warnings for online forums, and providing regular supervision and training so that peers are prepared and feel confident to support vulnerable people while maintaining their own emotional health

    Naloxegol and Postoperative Urinary Retention: A Randomized Trial

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    BACKGROUND: Naloxegol antagonizes peripheral opioid-related side effects without preventing opioid-related analgesia. However, the effect of naloxegol on opioid-induced bladder dysfunction remains unknown. HYPOTHESIS: patients given naloxegol have lower residual bladder urine volume than those given placebo. METHODS: 136 patients scheduled for elective hip and knee surgery were randomized to oral naloxegol or placebo given the morning of surgery, and on the first two postoperative mornings. Residual urine volume was measured ultrasonographically within 30 min after voiding once in the morning and once in the afternoon for two postoperative days. Opioid-related Symptom Distress Scale (ORSDS), the need for indwelling urinary catheterization, and quality of recovery (QoR) score were secondary outcomes. RESULTS: 67 were randomized to naloxegol and 64 to placebo. We did not identify a significant effect on urine residual volume, with an estimated ratio of geometric means of 0.9 (0.3, 2.6), p = 0.84. There were no significant differences in ORSDS or QoR. There were 19 (29%) patients assigned to naloxegol who needed indwelling urination catheterization versus 7 (11%) patients in the placebo group, p = 0.012. CONCLUSIONS: Our results do not support use of naloxegol for postoperative urinary retention after hip and knee surgery

    Risk algorithm using serial biomarker measurements doubles the number of screen-detected cancers compared with a single-threshold rule in the United Kingdom collaborative trial of ovarian cancer screening

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    PURPOSE: Cancer screening strategies have commonly adopted single-biomarker thresholds to identify abnormality. We investigated the impact of serial biomarker change interpreted through a risk algorithm on cancer detection rates. PATIENTS AND METHODS: In the United Kingdom Collaborative Trial of Ovarian Cancer Screening, 46,237 women, age 50 years or older underwent incidence screening by using the multimodal strategy (MMS) in which annual serum cancer antigen 125 (CA-125) was interpreted with the risk of ovarian cancer algorithm (ROCA). Women were triaged by the ROCA: normal risk, returned to annual screening; intermediate risk, repeat CA-125; and elevated risk, repeat CA-125 and transvaginal ultrasound. Women with persistently increased risk were clinically evaluated. All participants were followed through national cancer and/or death registries. Performance characteristics of a single-threshold rule and the ROCA were compared by using receiver operating characteristic curves. RESULTS: After 296,911 women-years of annual incidence screening, 640 women underwent surgery. Of those, 133 had primary invasive epithelial ovarian or tubal cancers (iEOCs). In all, 22 interval iEOCs occurred within 1 year of screening, of which one was detected by ROCA but was managed conservatively after clinical assessment. The sensitivity and specificity of MMS for detection of iEOCs were 85.8% (95% CI, 79.3% to 90.9%) and 99.8% (95% CI, 99.8% to 99.8%), respectively, with 4.8 surgeries per iEOC. ROCA alone detected 87.1% (135 of 155) of the iEOCs. Using fixed CA-125 cutoffs at the last annual screen of more than 35, more than 30, and more than 22 U/mL would have identified 41.3% (64 of 155), 48.4% (75 of 155), and 66.5% (103 of 155), respectively. The area under the curve for ROCA (0.915) was significantly (P = .0027) higher than that for a single-threshold rule (0.869). CONCLUSION: Screening by using ROCA doubled the number of screen-detected iEOCs compared with a fixed cutoff. In the context of cancer screening, reliance on predefined single-threshold rules may result in biomarkers of value being discarded

    Current State of Evidence for Medication Treatment of Preschool Internalizing Disorders

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    Psychotropic medications are being prescribed off-label by psychiatrists to treat preschool children diagnosed with internalizing disorders. In this review, the current state of evidence is presented for medications used to treat preschool children (ages 2-5 year olds) diagnosed with anxiety and/or depressive disorders. Eleven studies were systematically identified for this review based on a priori criteria. Overall, the available literature revealed that studies addressing the medication treatment of internalizing disorders in preschoolers are extremely limited and represent relatively weak research methodologies. Given the increasing prevalence of the use of psychotropic medications to treat preschool children and the unique challenges associated with working with this population, it is imperative that mental health practitioners are aware of the current, albeit limited, research on this practice to help make informed treatment decisions. Suggestions about how to monitor potential costs and benefits in those unique cases in which psychopharmacological treatments might be considered for young children are given. Moreover, areas of additional research for this population are discussed
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