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We use high-resolution Solar Dynamics Observatory (SDO)/Atmospheric Imaging Assembly observations to study the evolution of the coronal loops in a flaring solar active region, NOAA 11158. We identify three distinct phases of the coronal loop dynamics during this event: (1) slow-rise phase: slow rising motion of the loop-tops prior to the flare in response to the slow rise of the underlying flux rope; (2) collapse phase: sudden contraction of the loop-tops, with the lower loops collapsing earlier than the higher loops; and (3) oscillation phase: the loops exhibit global kink oscillations after the collapse phase at different periods, with the period decreasing with the decreasing height of the loops. The period of these loop oscillations is used to estimate the field strength in the coronal loops. Furthermore, we also use SDO/Helioseismic and Magnetic Imager (HMI) observations to study the photospheric changes close to the polarity inversion line (PIL). The longitudinal magnetograms show a stepwise permanent decrease in the magnetic flux after the flare over a coherent patch along the PIL. Furthermore, we examine the HMI Stokes I,Q,U,V profiles over this patch and find that the Stokes-V signal systematically decreases while the Stokes-Q and U signals increase after the flare. These observations suggest that close to the PIL the field configuration became more horizontal after the flare. We also use HMI vector magnetic field observations to quantify the changes in the field inclination angle and find an inward collapse of the field lines toward the PIL by ~10°. These observations are consistent with the "coronal implosion" scenario and its predictions about flare-related photospheric field changes. [ABSTRACT FROM AUTHOR]

We analyze flare-associated transverse oscillations in a quiescent solar prominence on 2010 September 8-9. Both the flaring active region and the prominence were located near the west limb, with a favorable configuration and viewing angle. The full-disk extreme ultraviolet (EUV) images of the Sun obtained with high spatial and temporal resolution by the Atmospheric Imaging Assembly on board the Solar Dynamics Observatory show flare-associated lateral oscillations of the prominence sheet. The STEREO-A spacecraft, 81.°5 ahead of the Sun-Earth line, provides an on-disk view of the flare-associated coronal disturbances. We derive the temporal profile of the lateral displacement of the prominence sheet by using the image cross-correlation technique. The displacement curve was de-trended and the residual oscillatory pattern was derived. We fit these oscillations with a damped cosine function with a variable period and find that the period is increasing. The initial oscillation period (P0) is ∼28.2 minutes and the damping time (τD) ∼ 44 minutes. We confirm the presence of fast and slow EUV wave components. Using STEREO-A observations, we derive a propagation speed of ∼250 km s–1 for the slow EUV wave by applying the time-slice technique to the running difference images. We propose that the prominence oscillations are excited by the fast EUV wave while the increase in oscillation period of the prominence is an apparent effect, related to a phase change due to the slow EUV wave acting as a secondary trigger. We discuss implications of the dual trigger effect for coronal prominence seismology and scaling law studies of damping mechanisms. [ABSTRACT FROM AUTHOR]

We discuss a promising solid-state system that emits single photons at room temperature in the blue-green range, making it an attractive candidate for quantum communications in free space and underwater. The active element is a core-shell ZnSe tapered nanowire embedding a single CdSe quantum dot grown by molecular beam epitaxy. A patterned substrate enables a comprehensive study of a single nanowire using various methods. Our source shows potential for achieving a total brightness of 0.17 photon per pulse and anti-bunching with g (2) (0) < 0.3 within a restricted spectral window. Additionally, we analyze the impact of charged excitons on the g (2) (0) value in different spectral ranges.

Background: Allergy immunotherapy (AIT), in the form of subcutaneous immunotherapy (SCIT) with alum-precipitated aqueous extracts, SCIT with a modified ragweed pollen allergen tyrosine adsorbate (MRPATA; Pollinex ® -R), or a sublingual immunotherapy (SLIT)-tablet are options for the treatment of ragweed pollen allergic rhinoconjunctivitis (ARC) in Canadian children. A cost minimization analysis evaluated the economic implications of the use of the ragweed SLIT-tablet vs SCIT in Canadian children with ragweed ARC., Methods: A cost minimization analysis was conducted comparing the short ragweed SLIT-tablet, 12 Amb a 1-U, preseasonally with preseasonal ragweed SCIT, annual ragweed SCIT, or MRPATA. The analysis was conducted over a time horizon of 3 years from a public payer perspective in Ontario and Quebec. Resources and costs associated with medication and services of healthcare professionals were considered for each treatment. The resource and cost input values for the model were obtained from published literature and validated by Canadian clinical experts in active allergy practice. A discount rate of 1.5% was applied. Several scenario analyses were conducted to determine the impact of many of the key base case assumptions on the outcomes., Results: Over the total 3-year time horizon, the ragweed SLIT-tablet had a potential cost savings of $900.14 in Ontario and $1023.14 in Quebec when compared with preseasonal ragweed SCIT, of $6613.22 in Ontario and $8750.64 in Quebec when compared with annual ragweed SCIT, and $79.62 in Ontario and $429.49 in Quebec when compared with MRPATA. The ragweed SLIT-tablet had higher drug costs compared with the other AIT options, but lower costs for healthcare professional services. The lower costs for healthcare professional services with the ragweed SLIT-tablet were driven by the need for fewer office visits than SCIT. Scenario analysis indicated that costs were most impacted by including societal costs (e.g., costs associated with patient/caregiver travel and time lost). The potential cost savings of the ragweed SLIT-tablet versus SCIT and MRPATA was maintained in most scenarios., Conclusions: In this cost minimization analysis, the ragweed SLIT-tablet provided estimated cost savings from a public payer perspective for the treatment of ragweed ARC in Canadian children compared with SCIT or MRPATA., (© 2023. The Author(s).)

Background: Rib resection in thoracic outlet decompression can result in significant postoperative pain requiring high levels of opioid medications. We evaluated the impact of a bupivacaine infusing pleural catheter on postoperative pain and opioid usage in patients undergoing rib resection for thoracic outlet syndrome. We hypothesized that delivery of local anesthetic via the pleural catheter would improve postoperative pain control compared to standard multimodal analgesia, and that the use of the catheter would decrease opioid use during the index hospitalization and prescriptions for opioid pain medications at discharge., Methods: We conducted a single-center retrospective cohort study of 26 patients who underwent rib resection for thoracic outlet decompression. Primary outcome was opioid consumption during the index hospitalization, measured in morphine milligram equivalents (MME). Secondary outcomes were MME prescribed at discharge and pain scores during the index hospitalization before and after the pleural drain and pleural catheter were removed., Results: Patients in the bupivacaine infusion pleural catheter group (n = 11) had significantly lower MME usage during the index hospitalization (22.5 [1.9, 65.6] vs. 119.8 [76.5, 167.4]), and significantly lower MME prescribed at discharge (0 [0, 37.5] vs. 225 [183, 315]), compared to standard multimodal analgesia in controls (n = 15). Only 3 patients in the bupivacaine pleural catheter group were discharged with any opioid prescriptions (27%), compared to 14 patients in the control group (93%). There was no difference in postoperative pain scores between groups before or after removal of the pleural drain, which was placed in all cases (P = 0.31 and P = 0.76, respectively)., Conclusions: Intraoperative placement of a bupivacaine infusion pleural catheter significantly reduced opioid use during the index hospitalization and opioid prescribing at discharge. Anesthetic infusion pleural catheters should be the treatment modality of choice for postoperative pain management in patients undergoing thoracic outlet decompression., (Copyright © 2022 Elsevier Inc. All rights reserved.)

The early stage of growth of semiconductor nanowires is studied in the case where the sidewall adatoms have a short diffusion length due to a strong desorption. Experimental results are described for the growth of ZnSe nanowires by molecular beam epitaxy. They are discussed and interpreted using the Burton-Cabrera-Frank description of the propagation of steps along the sidewalls, and compared to other II-VI and III-V nanowires. The role of the growth parameters and the resulting shape of the nanowires (cylinder, cone, or both combined) are highlighted., (© 2022 IOP Publishing Ltd.)

Background: A cost-minimization analysis (CMA) was performed to evaluate the economic implications of introducing the SQ Tree sublingual immunotherapy (SLIT)-tablets marketed as ITULATEK® (Health Canada regulatory approval in April 2020) for the treatment of pollen-induced (birch, alder and/or hazel) seasonal allergic rhinitis in Canada (Ontario and Quebec), where Tree Pollen subcutaneous immunotherapy (SCIT) is already an available treatment option., Methods: A CMA was deemed appropriate and was based on the assumption that the SQ Tree SLIT-tablets have comparable efficacy to Tree Pollen SCIT. A societal perspective was adopted in the model, including relevant costs of medications, costs of health care services, and productivity losses. The time horizon in the model was three years, which corresponds to a minimal treatment course of allergy immunotherapy. Resource use and costs were based on published sources, where available, and validated by Canadian specialist clinicians (allergists) in active practice in Ontario and in Quebec, where applicable. A discount rate of 1.5% was applied in accordance with the Canadian Agency for Drugs and Technologies in Health (CADTH) guidelines. To assess the robustness of the results, scenario analyses were performed by testing alternative assumptions for selected parameters (e.g., Tree Pollen SCIT resource use, discount rates, number of injections, annual SCIT dosing with maintenance injections, and nurse time support), to evaluate their impact on the results of the analysis., Results: The direct costs, including the drug costs, and physician services costs, for three years of treatment, were similar for both SQ Tree SLIT-tablets vs. Tree Pollen SCIT in both Ontario and Quebec ($2799.01 and $2838.70 vs. $2233.76 and $2266.05 respectively). However, when the indirect costs (including patient's travel expenses and lost working hours) are included in the model, total savings for the treatment with SQ Tree SLIT-tablets of $1111.79 for Ontario and $1199.87 for Quebec were observed. Scenario analyses were conducted and showed that changes in assumptions continue to result in the savings of SQ Tree SLIT- tablets over Tree Pollen SCIT., Conclusions: The CMA indicates that SQ Tree SLIT-tablets are a cost-minimizing alternative to Tree Pollen SCIT when considered from a societal perspective in Ontario and Quebec.

We investigate the restructuring of the magnetic field in sunspots associated with two flares: the X6.5 flare on 6 December 2006 and the X2.2 flare on 15 February 2011. The observed changes were evaluated with respect to the so-called twist-removal model, in which helicity (twist) is removed from the corona as the result of an eruption. Since no vector magnetograms were available for the X6.5 flare, we applied the azimuthal symmetry approach to line-of-sight magnetograms to reconstruct the pseudo-vector magnetic field and investigate the changes in average twist and inclination of magnetic field in the sunspot around the time of the flare. For the X2.2 flare, results from the full vector magnetograms were compared with the pseudo-vector field data. For both flares, the data show changes consistent with the twist-removal scenario. We also evaluate the validity of the azimuthal symmetry approach on simple isolated round sunspots. In general, the derivations based on the azimuthal symmetry approach agree with true-vector field data though we find that even for symmetric sunspots the distribution of the magnetic field may deviate from an axially symmetric distribution.

Background: The over-the-scope clip (OTSC) provides more durable and full-thickness closure as compared with standard clips. Only case reports and small case series have reported on outcomes of OTSC closure of GI defects., Objective: To describe a large, multicenter experience with OTSCs for the management of GI defects. Secondary goals were to determine success rate by type of defect and type of therapy and to determine predictors of treatment outcomes., Design: Multicenter, retrospective study., Setting: Multiple, international, academic centers., Patients: Consecutive patients who underwent attempted OTSC placement for GI defects, either as a primary or as a rescue therapy., Interventions: OTSC placement to attempt closure of GI defects., Main Outcome Measurements: Long-term success of the procedure., Results: A total of 188 patients (108 fistulae, 48 perforations, 32 leaks) were included. Long-term success was achieved in 60.2% of patients during a median follow-up of 146 days. Rate of successful closure of perforations (90%) and leaks (73.3%) was significantly higher than that of fistulae (42.9%) (P < .05). Long-term success was significantly higher when OTSCs were applied as primary therapy (primary 69.1% vs rescue 46.9%; P = .004). On multivariate analysis, patients who had OTSC placement for perforations and leaks had significantly higher long-term success compared with those who had fistulae (OR 51.4 and 8.36, respectively)., Limitations: Retrospective design and multiple operators with variable expertise with the OTSC device., Conclusion: OTSC is safe and effective therapy for closure of GI defects. Clinical success is best achieved in patients undergoing closure of perforations or leaks when OTSC is used for primary or rescue therapy. Type of defect is the best predictor of successful long-term closure., (Copyright © 2014 American Society for Gastrointestinal Endoscopy. Published by Elsevier Inc. All rights reserved.)

Background: Liquid nitrogen endoscopic spray cryotherapy can safely and effectively eradicate high-grade dysplasia in Barrett's esophagus (BE-HGD). Long-term data on treatment success and safety are lacking., Objective: To assess the long-term safety and efficacy of spray cryotherapy in patients with BE-HGD., Design: Single-center, retrospective study., Setting: Tertiary-care referral center., Patients: A total of 32 patients with BE-HGD of any length., Intervention: Patients were treated with liquid nitrogen spray cryotherapy every 8 weeks until complete eradication of HGD (CE-HGD) and intestinal metaplasia (CE-IM) was found by endoscopic biopsy. Surveillance endoscopy with biopsies was performed for at least 2 years., Main Outcome Measurements: CE-HGD, CE-IM, durability of response, disease progression, and adverse events., Results: CE-HGD was 100% (32/32), and CE-IM was 84% (27/32) at 2-year follow-up. At last follow-up (range 24-57 months), CE-HGD was 31/32 (97%), and CE-IM was 26/32 (81%). Recurrent HGD was found in 6 (18%), with CE-HGD in 5 after repeat treatment. One patient progressed to adenocarcinoma, downgraded to HGD after repeat cryotherapy. BE segment length ≥3 cm was associated with a higher recurrence of IM (P = .004; odds ratio 22.6) but not HGD. No serious adverse events occurred. Stricture was seen in 3 patients (9%), all successfully dilated., Limitations: Retrospective study design, small sample size., Conclusion: In patients with BE-HGD, liquid nitrogen spray cryotherapy has an acceptable safety profile and success rate for eliminating HGD and IM and is associated with a low rate of recurrence or progression to cancer with long-term follow-up., (Copyright © 2013 American Society for Gastrointestinal Endoscopy. Published by Mosby, Inc. All rights reserved.)

Background: Complex biliary stones often require temporary stent placement before a repeat attempt at extraction. To date, covered self-expandable metal stents (CSEMSs) have not been formally investigated for this indication., Objective: To evaluate the efficacy and safety of CSEMSs in patients with retained complex biliary stones., Design: Retrospective case series., Setting: Large quaternary-care center., Patients: Thirty-six patients (24 women) with complex biliary stones with incomplete stone clearance after endoscopic retrograde cholangiography (ERC) with biliary sphincterotomy., Interventions: Patients with incomplete stone clearance after ERC with biliary sphincterotomy underwent temporary placement of CSEMSs, with subsequent removal before repeat stone extraction., Main Outcome Measurements: Success achieving immediate biliary drainage and eventual complete duct clearance. Procedure-related complications were also assessed., Results: CSEMS placement was successful in establishing immediate biliary drainage in all 36 patients. Complete duct clearance at repeat ERC was achieved in 29 of 35 patients after a mean duration of 6.4 weeks. Four of the remaining 6 patients underwent sequential CSEMS placement, with eventual duct clearance after multiple ERCPs. There were no complications related to biliary obstruction. One patient died of a nonbiliary cause. Of the total 42 CSEMSs placed, there were 4 cases (9.5%) of clinically insignificant stent migration., Limitations: Single-center experience, retrospective design., Conclusions: CSEMSs permit management of complex biliary stones, but require multiple sessions. The cost-effectiveness of this technique needs further investigation., (Copyright © 2011 American Society for Gastrointestinal Endoscopy. Published by Mosby, Inc. All rights reserved.)

Purpose: Covered self-expanding metal stents (CSEMS) have been used for palliation of malignant distal biliary strictures. Occlusion of the cystic duct by CSEMS may be complicated by cholecystitis. This potentially could be prevented by placement of a transpapillary gallbladder stent (GBS)., Patients and Methods: Between 11/2006 and 10/2007, a total of 73 patients (50 male) aged 65 +/- 14 years underwent CSEMS placement for palliation of malignant obstructive jaundice. In cases where CSEMS placement caused occlusion of the cystic duct, a 7 French transpapillary pigtail gallbladder stent (GBS) was inserted to prevent cholecystitis., Results: Of the 73 patients, 18 had a prior cholecystectomy; 34 had the CSEMS placed below the cystic duct insertion. In 19 out of the 21 patients who had a CSEMS covering the cystic duct ostium, GBS placement was attempted, which was successful in 11 individuals (58%). An attempt to access the gallbladder was complicated by wire perforation of the cystic duct in three patients; one patient requiring emergent cholecystostomy tube placement. None of the patients who underwent successful GBS placement developed cholecystitis. One GBS dislodged and was repositioned. Cholecystitis occurred in two (20%) of the ten patients without transpapillary gallbladder decompression who had a CSEMS covering the cystic duct., Conclusions: The ideal placement of a CSEMS is below the cystic duct insertion. Should the cystic duct ostium be occluded, placement of a GBS should be considered to minimize the risk of cholecystitis.

The present study is designed to investigate the hypolipidemic effect of ethanolic extract from the leaves of Hibiscus sabdariffa L. (HSEE) in hyperlipidemic rats. In the present work, HSEE was evaluated at three doses (i.e. 100, 200 and 300 mg/kg, orally) in cholesterol-induced (2 g/kg, orally) hyperlipidemic Wistar rats. Atorvastatin (10 mg/kg, orally) was used as the standard drug. Administration of HSEE (200 mg/kg and 300 mg/kg) together with continuous cholesterol feeding for four weeks showed significant reduction in serum cholesterol level by 18.5% and 22%, respectively (p < 0.05); serum triglyceride level by 15.6% and 20.6%, respectively (p < 0.05); serum LDL level by 24% and 30%, respectively (p < 0.05), and serum VLDL level by 15.5% and 20.5%, respectively (p < 0.05), as compared to cholesterol group. However, no significant change in HDL level was observed. HSEE 300 mg/kg was more effective than HSEE 200 mg/kg dose but less effective than the standard drug, atorvastatin. HSEE 100 mg/kg did not show any significant reduction in lipid levels. These results indicate that HSEE exhibit the hypolipidemic effect and among all HSEE groups investigated, HSEE 300 mg/kg has the best hypolipidemic effect.

Background: Partially covered metal stents (PCMS) have been increasingly used for both malignant and benign biliary indications. This study reports their complications and subsequent management., Methods: Over 5 years, all patients receiving biliary PCMS were followed prospectively until stent-related dysfunction or death. Data were analyzed for the following variables: primary disease, time until revision, and type and reason for revision., Results: PCMS were placed in 396 patients (247 with malignant biliary strictures and 149 with benign biliary disease). Complications were observed in 70 patients (18%), occurring a mean time following placement of 159 days. Duodenal migration occurred in 27 cases (6.8%), while proximal migration occurred in 9 cases (2.3%). Cholecystitis was documented in 13 cases (3.3%). There were six cases of stent occlusion due to debris or sludge (1.6%), four cases of pancreatitis (1%), four cases of tumor overgrowth (1%), three cases of benign stenosis in the uncovered portion of the PCMS (0.8%), two cases of abdominal pain (0.5%), one case of an infected biloma (0.3%), and one case of a liver abscess (0.3%)., Conclusions: Major complications associated with PCMS placement include migration and cholecystitis. Their management includes endoscopic revision, cholecystectomy, and gallbladder drainage. Further improvements in the structure and composition of PCMS may prevent these complications.

Background: Current management of malignant gastric outlet obstruction (GOO) includes surgical diversion or enteral stent placement for unresectable cancer. We analyzed the long-term results, predictive factors of outcomes, and complications associated with enteral stents with focus on their management., Methods: Between 1997 and 2007, 46 patients with malignant GOO underwent placement of self-expandable metal stents (SEMS) for palliation. Patients were captured prospectively after 2001 and followed until complication or death. Patency, management of complications, and long-term survival were analyzed., Results: Forty-six patients had a mean survival of 152 +/- 235 days and a mean SEMS patency rate of 111 +/- 220 days. SEMS patency rates of 98%, 74%, and 57% at 1, 3, and 6 months were seen. Thirteen patients presented with obstruction and included two SEMS migration, two early occlusion, one fracture, four malignant ingrowth, and four with delayed clinical failure. Interventions included seven endoscopic revisions with three SEMS replacements. Six had percutaneous endoscopic gastrostomy with jejunal arm placed. Two patients eventually underwent surgical bypass. Two patients required surgery for complications including delayed duodenal perforation and aortoenteric fistula., Conclusions: SEMS effectively palliate gastric outlet obstructions that result from upper gastrointestinal malignancies. Their benefits offset potential complications or malfunctions, when a pluridisciplinary approach is adopted.