Bulky phenanthracenyl imidazolium-derived carbene ligands were investigated for copper-free Sonogashira coupling with terminal acetylenes. Aryl bromides and iodides gave coupled products in excellent ...yields from the Pd(PPh3)2Cl2 complex with potassium t-butoxide and 18-crown-6 in THF. A remarkable dependence on the size of the ligand was found. The highest yields were obtained with the bulky 2,9-dicyclohexyl-10-phenanthryl ligand 5.
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IJS, KILJ, NUK, PNG, UL, UM
We present a miniaturized ultrafast laser surgery probe with improved miniaturized optics to deliver higher peak powers and enable higher surgical speeds than previously possible. A custom-built ...miniaturized CaF
objective showed no evidence of the strong multiphoton absorption observed in our previous ZnS-based probe, enabling higher laser power delivery to the tissue surface for ablation. A Kagome fiber delivered ultrashort pulses from a high repetition rate fiber laser to the objective, producing a focal beam radius of 1.96 μm and covering a 90×90 μm
scan area. The probe delivered the maximum available fiber laser power, providing fluences >6 J/cm
at the tissue surface at 53% transmission efficiency. We characterized the probe's performance through a parametric ablation study on bovine cortical bone and defined optimal operating parameters for surgery using an experimental- and simulation-based approach. The entire opto-mechanical system, enclosed within a 5-mm diameter housing with a 2.6-mm diameter probe tip, achieved material removal rates >0.1 mm
/min, however removal rates were ultimately limited by the available laser power. Towards a next generation surgery probe, we simulated maximum material removal rates when using a higher power fiber laser and found that removal rates >2 mm
/min could be attained through appropriate selection of laser surgery parameters. With future development, the device presented here can serve as a precise surgical tool with clinically viable speeds for delicate applications such as spinal decompression surgeries.
Focused Cardiac Ultrasound Andrus, Phillip; Dean, Anthony
Global heart,
12/2013, Volume:
8, Issue:
4
Journal Article
Peer reviewed
Open access
Abstract The use of point-of-care ultrasound of the heart is becoming more widespread. A variety of users have joined traditional users of cardiac ultrasound, cardiologists, and are imaging their ...patients in real time at the point of care. Patients with undifferentiated shock, hypotension, chest pain, or dyspnea are ideal candidates for focused cardiac ultrasound (FOCUS). In addition, any patient in whom the diagnosis of pericardial effusion or tamponade, pulmonary embolism, or left ventricular dysfunction is suspected would benefit from FOCUS. Of particular importance is the use of FOCUS to rapidly determine the etiology of cardiac arrest. This review will detail the indications, techniques, and limitations of FOCUS in these patients.
Spurred by the Coronavirus infectious disease 2019 pandemic, aerosol containment devices (ACDs) were developed to capture infectious respiratory aerosols generated by patients at their source. Prior ...reviews indicated that such devices had low evidence of effectiveness, but did not address how ACDs should be evaluated, how well they should perform, nor have clearly defined performance standards. Towards developing design criteria for ACDs, two questions were posed: 1) What characteristics have guided the design of ACDs? 2) How have these characteristics been evaluated?
A scoping review was performed consistent with PRISMA guidelines. Data were extracted with respect to general study information, intended use of the device, device design characteristics and evaluation.
Fifty-four articles were included. Evaluation was most commonly performed with respect to device aerosol containment (n = 31, 61%), with only 5 (9%), 3 (6%) and 8 (15%) formally assessing providing experience, patient experience and procedure impact, respectively. Nearly all of the studies that explored provider experience and procedure impact studied intubation. Few studies provided a priori performance criteria for any evaluation metric, or referenced any external guidelines by which to bench mark performance.
With respect to aerosol containment, ACDs should reduce exposure among HCP with the device compared with the absence of the device, and provide ≥90% reduction in respirable aerosols, equivalent in performance to N95 filtering facepiece respirators, if the goal is to reduce reliance on personal protective equipment. The ACD should not increase awkward or uncomfortable postures, or adversely impact biomechanics of the procedure itself as this could have implications for procedure outcomes. A variety of standardized instruments exist to assess the experience of patients and healthcare personnel. Integration of ACDs into routine clinical practice requires rigorous studies of aerosol containment and the user experience.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Two Donax obesulus and two Protothaca asperrima shells collected prior to the nuclear testing of the 1950's were micromilled at sub-seasonal resolution to yield new reservoir effect (ΔR) estimates ...for the coast of Peru. Shells from northern (4°40′S to 8°14′S) and central (13°52′S) Peru produced ΔR values of 123 ± 50 and 110 ± 49 years respectively. We found such values statistically indistinguishable from each other while reporting intra-annual ΔR variability along shells ontogeny in agreement with previously published regional ΔR values. This similarity suggests radiocarbon dating of short-lived (<1.5 years) mollusks shells is a useful tool for comparing marine radiocarbon signals. Additionally, our analysis of ΔR and δ18O changes along shells' ontogeny found a tenuous relationship between them. We are not the first one to report these phenomena in Peruvian upwelling, but we are the first to suggest that fast Lagrangian water mixing as a mechanism behind it.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
The impact of required self-directed activities (SDAs) measured by written exam on advanced pharmacy practice experiences (APPEs) has not been reported. The primary objective of this study was to ...determine the validity and reliability of a pre/post exam to measure knowledge when SDAs are incorporated into primary care APPEs. Secondary objectives included assessment of pre/post exam scores and students' perceptions of their learning through SDAs.
Two faculty implemented required SDAs and a pre/post-exam in their APPEs. Face and content validity were assessed using expert consensus. A retrospective exam of student performance from May 2016 to April 2018 was performed (n = 42). Additional APPE assessment scores were also collected to determine correlations and establish criterion validity. Students who completed the APPE during May 2016 to February 2017 (n = 17) were invited to complete an anonymous, 15-item cross-sectional survey to assess student perceptions of the activities. Differences in self-rated knowledge before and after the rotation were assessed.
Pre-exam and post-exam scores positively correlated with journal club and the APPE grading rubric and final scores. Overall, interrater reliability was excellent. Significant improvement was seen between pre-/post exam scores with a mean (SD) change of 21.5% (9.4%). Thirteen (77%) students completed the anonymous survey and rated their perceived knowledge significantly higher after completing the SDAs.
The pre/post exam was valid, reliable, and positively correlated with other graded assignments. Significant improvements in exam scores and survey results support SDAs as an effective teaching method on primary care APPEs.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
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Resveratrol (RV) 1, a plant polyphenol, has proven effective in commercial products yet drawbacks include low bioavailability due to rapid metabolism. Structural modifications have ...led to a 4′-acetoxy analog 2 (4AR) now produced using a selective one-step esterification reaction. The one-step synthesis is shown together with expression of skin genes using human dermal models to establish 4AR 2 benefits to skin health. 4AR 2 at 1% in qPCR experiments using a human skin model significantly increased gene expression of the anti-aging factor, SIRT 1 by over 3.3-fold, extracellular matrix proteins collagen III, IV, elastin and tissue inhibitors of metalloproteinases (TIMP 1, 2), anti-oxidants CAT, LOX, superoxide dismutase (SOD 1, 2), metallothioneins (MT1H, MT1H), skin aging biomarkers fibrillin (FBN1), laminin (LAMB1), proliferating cell nuclear antigen (PCNA), skin growth factors (HBEGF, IGF1, NGF and TGF). 4AR 2 also decreased gene expression of inflammatory and skin-aging molecules (IL-1, IL-6, IL-8, COX-2, TNGRSF) and S100 calcium binding proteins A8, A9. These findings suggest that 4AR 2 has potential for topically treatment and prevention of skin aging.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
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