High-Density Periodically Ordered Magnetic Cobalt Ferrite Nanodot Arrays by Template-Assisted Pulsed Laser Deposition

Gao, Xingsen,Liu, Lifeng,Birajdar, Balaji,Ziese, Michael,Lee, Woo,Alexe, Marin,Hesse, Dietrich WILEY-VCH Verlag 2009 Advanced Functional Materials Vol.19 No.21

<P>A novel nanopatterning method using pulsed laser deposition through an ultrathin anodic aluminium oxide (AAO) membrane mask is proposed to synthesize well-ordered nanodot arrays of magnetic CoFe<SUB>2</SUB>O<SUB>4</SUB> that feature a wide range of applications like sensors, drug delivery, and data storage. This technique allows the adjustment of the array dimension from ∼35 to ∼300 nm in diameter and ∼65 to ∼500 nm in inter-dot distance. The dot density can be as high as 0.21 Terabit in.<SUP>−2</SUP>. The microstructure of the nanodots is characterized by SEM, TEM, and XRD and their magnetic properties are confirmed by well-defined magnetic force microscopy contrasts and by hysteresis loops recorded by a superconducting quantum interference device. Moreover, the high stability of the AAO mask enables the epitaxial growth of nanodots at a temperature as high as 550 °C. The epitaxial dots demonstrate unique complex magnetic domains such as bubble and stripe domains, which are switchable by external magnetic fields. This patterning method creates opportunities for studying novel physics in oxide nanomagnets and may find applications in spintronic devices.</P> <B>Graphic Abstract</B> <P>Well-ordered arrays of magnetic CoFe<SUB>2</SUB>O<SUB>4</SUB> nanodots are synthesized by a nanopatterning method using pulsed laser deposition through an ultrathin anodic aluminium oxide membrane. This technique allows a wide-range adjustment of array periodicity and dot dimension, as well as epitaxial growth of the nanodots. The epitaxial dots demonstrate complex magnetic domains such as bubble and stripe domains. <img src='wiley_img/1616301X-2009-19-21-ADFM200900422-content.gif' alt='wiley_img/1616301X-2009-19-21-ADFM200900422-content'> </P>

Fine-tuning the Electronic Structure of Organic Dyes for Dye-Sensitized Solar Cells

Gao, Peng,Tsao, Hoi Nok,Grä,tzel, Michael,Nazeeruddin, Mohammad K. American Chemical Society 2012 Organic letters Vol.14 No.17

<P>A series of metal-free organic dyes exploiting different combinations of (hetero)cyclic linkers (benzene, thiophene, and thiazole) and bridges (4<I>H</I>-cyclopenta[2,1-<I>b</I>:3,4-<I>b′</I>]dithiophene (CPDT) and benzodithiophene (BDT)) as the central π-spacers were synthesized and characterized. Among them, the sensitizer containing the thiophene and CPDT showed the most broad incident photon-to-current conversion efficiency spectra, resulting in a solar energy conversion efficiency (η) of 6.6%.</P><P><B>Graphic Abstract</B> <IMG SRC='http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/orlef7/2012/orlef7.2012.14.issue-17/ol301730c/production/images/medium/ol-2012-01730c_0006.gif'></P><P><A href='http://pubs.acs.org/doi/suppl/10.1021/ol301730c'>ACS Electronic Supporting Info</A></P>

Presentation and outcomes among inflammatory bowel disease patients with concurrent pneumatosis intestinalis: a case series and systematic review

( Youran Gao ),( Meka Uffenheimer ),( Michael Ashamallah ),( Gregory Grimaldi ),( Arun Swaminath ),( Keith Sultan ) 대한장연구학회 2020 Intestinal Research Vol.18 No.3

Background/Aims: Inflammatory bowel disease (IBD) involves chronic inflammation of the colon with ulcerative colitis (UC), and the colon and/or small intestine with Crohn’s disease (CD). Pneumatosis intestinalis (PI), characterized by compromise of the intestinal wall with gas-filled cysts, has rarely been reported with IBD. The presentation, best management and outcomes of PI with IBD are poorly defined. Methods: We conducted a search for PI in all abdominal computed tomography (CT) reports at 2 large tertiary care hospitals from January 1, 2010 to December 31, 2017, cross referenced to ICD codes for IBD. CT and chart review was performed to confirm PI and IBD respectively. A systematic review excluding case reports was performed for PI with IBD for comparison. Results: Of 5,990 patients with a CT abdomen report mentioning PI, we identified 11 cases of PI with IBD, 4 UC, 6 CD, and 1 indeterminate colitis. PI was limited to the small bowel in 5 patients, the right colon in 5, and small bowel and colonic in 1. All 3 mortalities had CD, small intestinal PI and portal/mesenteric venous gas. The systematic literature search identified 9 articles describing 58 patients with IBD and PI. These cases were mostly included in larger cohorts of PI patients without extractable data on presentation or outcomes in the IBD subpopulation. Conclusions: Ours appears to be the first reporting of presentations and outcomes, outside of case reports, for those with PI and IBD. The high mortality for those with CD and PI of the small bowel appears to define a group requiring more than supportive medical care. (Intest Res 2020;18:289- 296)

Stimuli-Responsive Polymers: Fundamental Considerations and Applications

Yongfeng Gao,Menglian Wei,Xue Li,Wenwen Xu,Andrews Ahiabu,Juliana Perdiz,Zining Liu,Michael J. Serpe 한국고분자학회 2017 Macromolecular Research Vol.25 No.6

Stimuli-responsive polymers are capable of changing their chemical and/ or physical properties in response to environmental stimuli. This unique feature has allowed stimuli-responsive polymers to be used in a variety of applications. In this review, we present a basic introduction to the theories that have been developed to describe polymer chains, brushes, and networks. We then detail numerous examples of how stimuli-responsive polymers can be used for sensing and biosensing, drug delivery, and as artificial muscles. While we focus the review on these particular areas, there are numerous other demonstrations of the applications of these fascinating materials, and we are certain that many applications have yet to be discovered.

Capillary Origami with Atomically Thin Membranes

Reynolds, Michael F.,McGill, Kathryn L.,Wang, Maritha A.,Gao, Hui,Mujid, Fauzia,Kang, Kibum,Park, Jiwoong,Miskin, Marc Z.,Cohen, Itai,McEuen, Paul L. American Chemical Society 2019 NANO LETTERS Vol.19 No.9

<P>Small-scale optical and mechanical components and machines require control over three-dimensional structure at the microscale. Inspired by the analogy between paper and two-dimensional materials, origami-style folding of atomically thin materials offers a promising approach for making microscale structures from the thinnest possible sheets. In this Letter, we show that a monolayer of molybdenum disulfide (MoS<SUB>2</SUB>) can be folded into three-dimensional shapes by a technique called capillary origami, in which the surface tension of a droplet drives the folding of a thin sheet. We define shape nets by patterning rigid metal panels connected by MoS<SUB>2</SUB> hinges, allowing us to fold micron-scale polyhedrons. Finally, we demonstrate that these shapes can be folded in parallel without the use of micropipettes or microfluidics by means of a microemulsion of droplets that dissolves into the bulk solution to drive folding. These results demonstrate controllable folding of the thinnest possible materials using capillary origami and indicate a route forward for design and parallel fabrication of more complex three-dimensional micron-scale structures and machines.</P> [FIG OMISSION]</BR>

Roles for the Lipid-signaling enzyme MitoPLD in mitochondrial dynamics, piRNA biogenesis, and spermatogenesis

( Qun Gao ),( Michael A. Frohman ) 생화학분자생물학회 (구 한국생화학분자생물학회) 2012 BMB Reports Vol.45 No.1

Phospholipase D (PLD), a superfamily of signaling enzymes that most commonly generate the lipid second messenger Phosphatidic Acid (PA), is found in diverse organisms from bacteria to man and functions in multiple cellular pathways. A fascinating member of the family, MitoPLD, is anchored to the mitochondrial surface and has two reported roles. In the first role, MitoPLD-generated PA regulates mitochondrial shape through facilitating mitochondrial fusion. In the second role, MitoPLD performs a critical function in a pathway that creates a specialized form of RNAi required by developing spermatocytes to suppress transposon mobilization during meiosis. This spermatocyte-specific RNAi, known as piRNA, is generated in the nuage, an electron-dense accumulation of RNA templates and processing proteins that localize adjacent to mitochondria in a structure also called intermitochondrial cement. In this review, we summarize recent findings on these roles for MitoPLD functions, highlighting directions that need to be pursued to define the underlying mechanisms. (BMB reports 2012; 45(1): 7-13)

Thermal Behavior of Methylammonium Lead-Trihalide Perovskite Photovoltaic Light Harvesters

Dualeh, Amalie,Gao, Peng,Seok, Sang Il,Nazeeruddin, Mohammad Khaja,Grä,tzel, Michael American Chemical Society 2014 Chemistry of materials Vol.26 No.21

<P>Recently organic–inorganic hybrid perovskites have attracted attention as light harvesting materials in mesoscopic cells. While a considerable number of deposition and formation methods have been reported for the perovskite crystalline material, most involve an annealing step. As such, the thermal behavior of this material and its individual components is of crucial interest. Here, we examine the thermal properties of the CH<SUB>3</SUB>NH<SUB>3</SUB>PbX<SUB>3</SUB> (X = I or Cl) perovskite using thermogravimetric analysis. The role of the precursors is exposed, and the effect of the formation of excess organic species is investigated. The sublimation behavior of the organic component is intensively scrutinized. Furthermore, differential scanning calorimetry is employed to probe the crystal phase structure, revealing subtle differences depending on the deposition method.</P><P><B>Graphic Abstract</B> <IMG SRC='http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/cmatex/2014/cmatex.2014.26.issue-21/cm502468k/production/images/medium/cm-2014-02468k_0004.gif'></P><P><A href='http://pubs.acs.org/doi/suppl/10.1021/cm502468k'>ACS Electronic Supporting Info</A></P>

Applications of Machine Learning Using Electronic Medical Records in Spine Surgery

John T. Schwartz,Michael Gao,Eric A. Geng,Kush S. Mody,Christopher M. Mikhail,Samuel K. Cho 대한척추신경외과학회 2019 Neurospine Vol.16 No.4

Developments in machine learning in recent years have precipitated a surge in research on the applications of artificial intelligence within medicine. Machine learning algorithms are beginning to impact medicine broadly, and the field of spine surgery is no exception. Electronic medical records are a key source of medical data that can be leveraged for the creation of clinically valuable machine learning algorithms. This review examines the current state of machine learning using electronic medical records as it applies to spine surgery. Studies across the electronic medical record data domains of imaging, text, and structured data are reviewed. Discussed applications include clinical prognostication, preoperative planning, diagnostics, and dynamic clinical assistance, among others. The limitations and future challenges for machine learning research using electronic medical records are also discussed.

Homogeneous percolation <i>versus</i> arrested phase separation in attractively-driven nanoemulsion colloidal gels

Helgeson, Matthew E.,Gao, Yongxiang,Moran, Shannon E.,Lee, Jinkee,Godfrin, Michael,Tripathi, Anubhav,Bose, Arijit,Doyle, Patrick S. The Royal Society of Chemistry 2014 SOFT MATTER Vol.10 No.17

<P>We elucidate mechanisms for colloidal gelation of attractive nanoemulsions depending on the volume fraction (<I>&phis;</I>) of the colloid. Combining detailed neutron scattering, cryo-transmission electron microscopy and rheological measurements, we demonstrate that gelation proceeds by either of two distinct pathways. For <I>&phis;</I> sufficiently lower than 0.23, gels exhibit homogeneous fractal microstructure, with a broad gel transition resulting from the formation and subsequent percolation of droplet–droplet clusters. In these cases, the gel point measured by rheology corresponds precisely to arrest of the fractal microstructure, and the nonlinear rheology of the gel is characterized by a single yielding process. By contrast, gelation for <I>&phis;</I> sufficiently higher than 0.23 is characterized by an abrupt transition from dispersed droplets to dense clusters with significant long-range correlations well-described by a model for phase separation. The latter phenomenon manifests itself as micron-scale “pores” within the droplet network, and the nonlinear rheology is characterized by a broad yielding transition. Our studies reinforce the similarity of nanoemulsions to solid particulates, and identify important qualitative differences between the microstructure and viscoelastic properties of colloidal gels formed by homogeneous percolation and those formed by phase separation.</P> <P>Graphic Abstract</P><P>Using thermoresponsive nanoemulsions, we demonstrate that colloidal gels prepared by quasi-equilibrium quenching can form by different mechanisms depending on the volume fraction (<I>&phis;</I>) of the colloid. <IMG SRC='http://pubs.rsc.org/services/images/RSCpubs.ePlatform.Service.FreeContent.ImageService.svc/ImageService/image/GA?id=c3sm52951g'> </P>

Adalimumab induction and maintenance therapy achieve clinical remission and response in Chinese patients with Crohn`s disease

( Kai Chun Wu ),( Zhi Hua Ran ),( Xiang Gao ),( Minhu Chen ),( Jie Zhong ),( Jian Qiu Sheng ),( Michael A Kamm ),( Simon Travis ),( Kori Wallace ),( Nael M Mostafa ),( Marisa Shapiro ),( Yao Li ),( Ro 대한장연구학회 2016 Intestinal Research Vol.14 No.2

Background/Aims: This was a Phase 2 study (NCT02015793) to evaluate the pharmacokinetics, safety, and efficacy of adalimumab in Chinese patients with Crohn`s disease (CD). Methods: Thirty, adult Chinese patients with CD (CD Activity Index [CDAI] 220-450; high-sensitivity [hs]-C-reactive protein [CRP] ≥3 mg/L) received double-blind adalimumab 160/80 mg or 80/40 mg at weeks 0/2, followed by 40 mg at weeks 4 and 6. An open-label extension period occurred from weeks 8-26; patients received 40 mg adalimumab every other week. Serum adalimumab concentration and change from baseline in fecal calprotectin (FC) were measured during the double-blind period. Clinical remission (CDAI <150), response (decrease in CDAI ≥70 points from baseline), and change from baseline in hs-CRP were assessed through week 26. Nonresponder imputation was used for missing categorical data and last observation carried forward for missing hs-CRP/FC values. No formal hypothesis was tested. Adverse events were monitored. Results: Mean adalimumab serum concentrations during the induction phase were 13.9-18.1 μg/mL (160/80 mg group) and 7.5-9.5 μg/mL (80/40 mg group). During the double-blind period, higher remission/ response rates and greater reductions from baseline in hs-CRP and FC were observed with adalimumab 160/80 mg compared to that with 80/40 mg. Adverse event rates were similar among all treatment groups. Conclusions: Adalimumab serum concentrations in Chinese patients with CD were comparable to those observed previously in Western and Japanese patients. Clinically meaningful remission rates and improvement in inflammatory markers were achieved with both dosing regimens; changes occurred rapidly with adalimumab 160/80 mg induction therapy. No new safety signals were reported. (Intest Res 2016;14:152-163)