892 research outputs found

    Stacked-graphene layers as engineered solid-electrolyte interphase (SEI) grown by chemical vapour deposition for lithium-ion batteries

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    A multi-layer of stacked-graphene (8 layers of basal planes) grown by chemical vapour deposition (CVD) is introduced as an artificial solid electrolyte interphase (SEI) layer onto a transition metal oxide cathode for lithium-ion batteries. The basal planes are generally regarded as a strong physical barrier that prevents lithium-ion diffusion, although it is believed that a small number of lithium-ions can migrate through the defect sites of the stacked layers. Interestingly, the unique design of the stacked-graphene perpendicular to the basal planes not only effectively suppresses the formation of instable SEI layers, but also achieves a reasonable amount of battery charge capacities. To correctly understand the impact from the stacked design, we further studied the rate kinetics difference between slow cycles (0.125 C→0.250 C→0.400 C→0.125 C) and rapid cycles (C→2 C→3 C→C). We propose that the clap-net like design of the stacked-graphene could enable the effective conducting pathway for electron transport, while protecting the active material inside. The magnetic measurements reveal the efficient Li+ (de)intercalation into graphene-layers. The artificial SEI also renders the electrode/electrolyte interface more stable against dynamic rate changes. The present approach provides a particular advantage in developing high stability battery that can be utilized at various charge rates

    Quantitative Microbiology of the Scalp in Non-Dandruff, Dandruff, and Seborrheic Dermatitis

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    The composition of the scalp microflora was assessed quantitatively in normal individuals and in patients with dandruff and seborrheic dermatitis, disorders characterized by increasing scalin. Three organisms were constantly found: (1) Pityrosporum, (2) aerobic cocci, and (3) Corynebacterium acnes. Pitrosporum (mainly Pityrosporum ovale) made up 46% of the total microflora in normals, 74% in dandruff, and 83% in seborrheic dermatitis. The geometric mean number of organisms per cm2 in non-dandruff subjects was 5.04 × 105; 9.22 × 105 in dandruff subjects; and 6.45 × 105 in those with seborrheic dermatitis. The cocci were dominantly Baird-Parkertype SII and no quantitative or qualitative change occurred in the scaling disorders. C. acnes comprised 26% of the flora on the normal scalp, 6% in dandruff, and only 1% in seborrheic dermatitis. These results differ significantly from previous reports which describe a much more complex microflora and suggest an etiologic role for microorganisms in dandruff

    APC loss in breast cancer leads to doxorubicin resistance via STAT3 activation

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    Resistance to chemotherapy is one of the leading causes of death from breast cancer. We recently established that loss of Adenomatous Polyposis Coli (APC) in the Mouse Mammary Tumor Virus – Polyoma middle T (MMTV-PyMT) transgenic mouse model results in resistance to cisplatin or doxorubicin-induced apoptosis. Herein, we aim to establish the mechanism that is responsible for APC-mediated chemotherapeutic resistance. Our data demonstrate that MMTV-PyMT;ApcMin/+ cells have increased signal transducer and activator of transcription 3 (STAT3) activation. STAT3 can be constitutively activated in breast cancer, maintains the tumor initiating cell (TIC) population, and upregulates multidrug resistance protein 1 (MDR1). The activation of STAT3 in the MMTV-PyMT;ApcMin/+ model is independent of interleukin 6 (IL-6); however, enhanced EGFR expression in the MMTV-PyMT;ApcMin/+ cells may be responsible for the increased STAT3 activation. Inhibiting STAT3 with a small molecule inhibitor A69 in combination with doxorubicin, but not cisplatin, restores drug sensitivity. A69 also decreases doxorubicin enhanced MDR1 gene expression and the TIC population enhanced by loss of APC. In summary, these results have revealed the molecular mechanisms of APC loss in breast cancer that can guide future treatment plans to counteract chemotherapeutic resistance

    Novel M4 Pediatrics Chief Program Utilizing Near-peer Teaching and Mentoring to Enhance Clerkship Curricula

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    Introduction: Near-peer teachers add many benefits to the academic, clinical performance, and enjoyment of near-peer learners in medical education. This enterprise describes and examines how the Creighton University School of Medicine M4 Pediatrics Chief Program fills a gap in medical education by offering an organized and formal methodology for near-peer teaching. The Creighton University M4 Pediatrics Chief Program utilizes select fourth year medical students to orient, teach basic clinical skills, mentor, and participate in curriculum development for the third year Pediatric clerkship students. Methods: Third year students (n=43) in their Pediatrics clerkship from September 2020 to February 2021 completed surveys at the end of the clerkship to assess the quality and effectiveness of the M4 Pediatrics Chief Program. Results: Students rated effectiveness of the Chiefs most highly as clerkship guides (4.29, SD=0.79), teachers (4.21, SD=0.92), and mentors (4.19, SD=0.75). Near-peer perspectives, education, provision of pertinent content, serving as a clerkship resource, and being a source of encouragement were the most beneficial aspects of the program. Students reported strong agreement all clerkships should have an M4 Chief Program (4.53, SD=0.88). Discussion: Because of the positive reviews by the third years students, the M4 Pediatrics Chief Program is now a permanent part of the Pediatric Clerkship. Additionally, other third year clerkships at Creighton University School of Medicine are adopting this model. Finally, the M4 students acting as the chiefs gain valuable leadership and educational skills. Conclusion: Based on positive perceptions of the “M4 Chief Program”, the authors recommend other medical schools consider initiating similar programs within their third year clerkships.https://digitalcommons.unmc.edu/chri_forum/1037/thumbnail.jp

    Complete Genome Sequence of Paraclostridium bifermentans DSM 14991

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    The complete genome sequence of Paraclostridium bifermentans was obtained by assembly of Illumina and Oxford Nanopore (ONT) reads. The sequence will enable study into the organism’s ability to biohydrogenate unsaturated acyl chains in the transformation of C20 polyunsaturated fatty acids (PUFAs) into the corresponding bioactive non-methylene-interrupted fatty acids (NMIFAs)

    Negligible‐Pb‐Waste and Upscalable Perovskite Deposition Technology for High‐Operational‐Stability Perovskite Solar Modules

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    An upscalable perovskite film deposition method combining raster ultrasonic spray coating and chemical vapor deposition is reported. This method overcomes the coating size limitation of the existing stationary spray, single‐pass spray, and spin‐coating methods. In contrast with the spin‐coating method (>90% Pb waste), negligible Pb waste during PbI2 deposition makes this method more environmentally friendly. Outstanding film uniformity across the entire area of 5 cm × 5 cm is confirmed by both large‐area compatible characterization methods (electroluminescence and scattered light imaging) and local characterization methods (atomic force microscopy, scanning electron microscopy, photoluminescence mapping, UV–vis, and X‐ray diffraction measurements on multiple sample locations), resulting in low solar cell performance decrease upon increasing device area. With the FAPb(I0.85Br0.15)3 (FA = formamidinium) perovskite layer deposited by this method, champion solar modules show a power conversion efficiency of 14.7% on an active area of 12.0 cm2 and an outstanding shelf stability (only 3.6% relative power conversion efficiency decay after 3600 h aging). Under continuous operation (1 sun light illumination, maximum power point condition, dry N2 atmosphere with <5% relative humidity, no encapsulation), the devices show high light‐soaking stability corresponding to an average T80 lifetime of 535 h on the small‐area solar cells and 388 h on the solar module

    Interaction and efficacy of Keigai-rengyo-to extract and acupuncture in male patients with acne vulgaris: A study protocol for a randomized controlled pilot trial

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    <p>Abstract</p> <p>Background</p> <p>In consideration of patients seeking to use traditional Chinese medicine, an evidence-based potentiality for safe and effective use of herbal medicine and acupuncture in treatment of acne vulgaris has been suggested. However, despite common use of a combination of herbal medicine and acupuncture in clinical practice, the current level of evidence is insufficient to draw a conclusion for an interaction and efficacy of herbal medicine and acupuncture. Therefore, considering these methodological flaws, this study was designed to assess the interaction and efficacy of an available herbal medicine, Keigai-rengyo-to extract (KRTE), and acupuncture for treatment of acne using the 2 × 2 factorial design and the feasibility of a large clinical trial.</p> <p>Methods/Design</p> <p>A randomized, assessor single blinded, 2 × 2 factorial pilot trial will be conducted. Forty four participants with acne vulgaris will be randomized into one of four groups: waiting list group (WL), KRTE only group (KO), acupuncture only group (AO), and KRTE and acupuncture combined treatment group (KA). After randomization, a total of 8 sessions of acupuncture treatment will be performed twice a week in the AO- and KA groups, respectively. Patients in the KO- and KA groups will be prescribed KRTE 3 times a day at a dose of 7.4 g after meals for 4 weeks. The following outcome measurements will be used in examination of subjects: the mean percentage change and the count change of inflammatory and non-inflammatory acne lesions, the Skindex 29, visual analogue scale (VAS) and investigator global assessment (IGA) from baseline to the end of the trial.</p> <p>Trial Registration</p> <p>The trial is registered with the Clinical Research Information Service (CRiS), Republic of Korea: KCT0000071.</p
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