RISS 학술연구정보서비스

검색
다국어 입력

http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.

변환된 중국어를 복사하여 사용하시면 됩니다.

예시)
  • 中文 을 입력하시려면 zhongwen을 입력하시고 space를누르시면됩니다.
  • 北京 을 입력하시려면 beijing을 입력하시고 space를 누르시면 됩니다.
닫기
    인기검색어 순위 펼치기

    RISS 인기검색어

      검색결과 좁혀 보기

      선택해제
      • 좁혀본 항목 보기순서

        • 원문유무
        • 원문제공처
          펼치기
        • 등재정보
        • 학술지명
          펼치기
        • 주제분류
          펼치기
        • 발행연도
          펼치기
        • 작성언어
        • 저자
          펼치기

      오늘 본 자료

      • 오늘 본 자료가 없습니다.
      더보기
      • 무료
      • 기관 내 무료
      • 유료
      • SCISCIESCOPUS

        Clockwork for neutrino masses and lepton flavor violation

        Ibarra, Alejandro,Kushwaha, Ashwani,Vempati, Sudhir K. North-Holland Pub. Co 2018 Physics letters. Section B Vol.780 No.-

        <P><B>Abstract</B></P> <P>We investigate the generation of small neutrino masses in a clockwork framework which includes Dirac mass terms as well as Majorana mass terms for the new fermions. We derive analytic formulas for the masses of the new particles and for their Yukawa couplings to the lepton doublets, in the scenario where the clockwork parameters are universal. When the universal Majorana mass vanishes, the zero mode of the clockwork sector forms a Dirac pair with the active neutrino, with a mass which is in agreement with oscillations experiments for a sufficiently large number of clockwork gears. On the other hand, when it does not vanish, neutrino masses are generated via the seesaw mechanism. In this case, and due to the fact that the effective Yukawa couplings of the higher modes can be sizable, neutrino masses can only be suppressed by postulating a large Majorana mass scale. Finally, we discuss the constraints on the mass scale of the clockwork fermions from the non-observation of the rare leptonic decay μ → e γ .</P>

      • SCISCIE

        Adsorption Properties of MFM-400 and MFM-401 with CO<sub>2</sub> and Hydrocarbons: Selectivity Derived from Directed Supramolecular Interactions

        Ibarra, Ilich A.,Mace, Amber,Yang, Sihai,Sun, Junliang,Lee, Sukyung,Chang, Jong-San,Laaksonen, Aatto,Schrö,der, Martin,Zou, Xiaodong American Chemical Society 2016 Inorganic Chemistry Vol.55 No.15

        <P>([Sc-2(OH)(2)(BPTC)]) (H4BPTC = biphenyl-3,3',5,5'-tetracarboxylit acid), MFM-400 (MFM = Manchester Framework Material; previously designated NOTT), and ([Sc(OH)-(TDA)]) (H(2)TDA = thiophene-2,5-dicarboxylic acid), MFM-401, both show xelective and, reversible capture of CO2. In particular, MFM-400 exhibits a reasonably high CO2 uptake at low pressures and competitive CO2/N-2 selectivity coupled to a moderate isosteric heat of adsorption (Q(st)) for CO2 (29.5 kJ mol(-1)) at zero coverage, thus affording a facile uptake release process. Grand canonical Monte Carlo (GCMC) and density functional theory (DFT) computational analyses of CO2 uptake in both materials confirmed preferential adsorption sites consistent with the higher CO2 uptake observed experimentally for MFM-400 over MFM-401 at low pressures. For MFM-400, the Sc-OH group participates in moderate interactions with CO2 (Q(st) = 33.5 kJ mol(-1)), and these are complemented by weak hydrogen-bonding interactions (O center dot center dot center dot H-C = 3.10-3.22 angstrom) from four surrounding aromatic -CH groups. In the case of MFM-401, adsorption is provided by cooperative interactions of CO2 with the Sc-OH group and one C-H group. The binding energies obtained by DFT analysis for the adsorption sites for both materials correlate well with the observed moderate isosteric heats of adsorption for CO2. GCMC simulations for both materials confirmed higher uptake of EtOH compared with nonpolar vapors of toluene and. cydohexane. This is in good Correlation with the experimental data, and DFT analysis confirmed the formation of a strong hydrogen bond between EtOH and the hydrogen atom of the hydroxyl group of the MFM-400 and MFM-401 framework (FIAT) with H-O-EtOH center dot center dot center dot H-O-FW distances of 1.77 arid 1.75 angstrom, respectively. In addition, the accessible regeneration of MFM-400 and MFM-401 and release of CO2 potentially provide minimal economic and environmental penalties.</P>

      • Potential for probing three-body decays of Long-Lived Particles with MATHUSLA

        Ibarra, Alejandro,Molinaro, Emiliano,Vogl, Stefan Elsevier 2019 Physics letters: B Vol.789 No.-

        <P><B>Abstract</B></P> <P>Several extensions of the Standard Model predict the existence of Long-Lived Neutral Particles (LLNPs) with masses in the multi-GeV range and decay lengths of O ( 100 m ) or longer. These particles could be copiously produced at the LHC, but the decay products cannot be detected with the ATLAS or CMS detectors. MATHUSLA is a proposed large-volume surface detector installed near ATLAS or CMS aimed to probe scenarios with LLNPs which offers good prospects for disentangling the physics underlying two-body decays into visible particles. In this work we focus on LLNP decays into three particles with one of them being invisible, which are relevant for scenarios with low scale supersymmetry breaking, feebly interacting dark matter or sterile neutrinos, among others. We analyze the MATHUSLA prospects to discriminate between two- and three-body LLNP decays, as well as the prospects for reconstructing the underlying model parameters.</P>

      • Molecular sensing and discrimination by a luminescent terbium–phosphine oxide coordination material

        Ibarra, Ilich A.,Hesterberg, Travis W.,Chang, Jong-San,Yoon, Ji Woong,Holliday, Bradley J.,Humphrey, Simon M. The Royal Society of Chemistry 2013 Chemical communications Vol.49 No.64

        <P>PCM-15 is a robust and recyclable sensor for the effective discrimination of a wide range of small molecules. Sensing is achieved by direct attenuation of the luminescence intensity of Tb(<SMALL>III</SMALL>) ions within the material. A competition study involving trace amounts of NH<SUB>3</SUB> in H<SUB>2</SUB> gas shows that PCM-15 can be used to quantitatively detect trace analytes.</P> <P>Graphic Abstract</P><P>PCM-15 is a robust and recyclable sensor for the effective discrimination of a wide range of small molecules. <IMG SRC='http://pubs.rsc.org/services/images/RSCpubs.ePlatform.Service.FreeContent.ImageService.svc/ImageService/image/GA?id=c3cc44575e'> </P>

      • KCI등재

        Catalytic cracking of raw bio-oil under FCC unit conditions over different zeolite-based catalysts

        Alvaro Ibarra,Idoia Hita,Miren J. Azkoiti,Jose M. Arandes,Javier Bilbao 한국공업화학회 2019 Journal of Industrial and Engineering Chemistry Vol.78 No.-

        The performance of different zeolite-based catalysts (HY, HZSM-5 and HBeta) on the catalytic cracking ofbio-oil has been explored, using a simulated riser reactor and resembling industrial FCC conditions. Theeffect of the C/O (catalyst/bio-oil) ratio and the zeolite types have been assessed. The level ofdeoxygenation is >61% (increasing with C/O ratio). Total hydrocarbon yield was higher for the HBetacatalyst (56 wt%), while the liquid hydrocarbons yields were relatively similar for all catalysts, obtaininghigher gasoline yields with the HY catalyst (46–55 wt%), and higher LPG yields with the HZSM-5 catalyst(12–14 wt%) due to its higher acidity. The HY zeolite produced more coke (4–7 wt%) given its capacity forretaining coke precursors within its micropores.

      • KCI등재

        Importance of Extract Standardization and In Vitro/Ex Vivo Assay Selection for the Evaluation of Antioxidant Activity of Botanicals: A Case Study on Three Rosmarinus officinalis L. Extracts

        Alvin Ibarra,Julien Cases,Antoine Bily,Kan He,Naisheng Bai,Marc Roller,Aure´lie Coussaert,Christophe Ripoll 한국식품영양과학회 2010 Journal of medicinal food Vol.13 No.5

        The overproduction of free radicals and oxygen reactive species is suspected to be implicated in a wide range of metabolic reactions that can have pernicious consequences in the development of a variety of human diseases. Botanical extracts are sources of antioxidants that counteract both free radicals and oxygen reactive species. The processing conditions used in the botanical extraction may influence the antioxidant composition; therefore, different extracts from the same plant may have different antioxidant properties. To illustrate this fact, we conducted a study using three commercial rosemary (Rosmarinus officinalis L.) leaf extracts. The three extracts were standardized to contain, respectively, 20% carnosic acid, 40% ursolic acid, or 20% rosmarinic acid. They were evaluated for their total (hydrophilic+lipophilic) antioxidant effects on oxygen radical absorbance capacity (ORAC), their ferric reducing/antioxidant power (FRAP), and their capacity to inhibit Cu2+-induced low-density lipoprotein (LDL) oxidation ex vivo. The ursolic acid extract showed the lowest antioxidant capacity on all models. The rosmarinic acid extract had an antioxidant capacity 1.5 times higher on ORAC and four times higher on FRAP than the carnosic acid extract. However, the carnosic acid extract was better than the rosmarinic acid extract in inhibiting the oxidation of LDL ex vivo. These results encourage conducting further studies to evaluate the carnosic acid and rosmarinic acid extracts in vivo. Our study offers an example of the importance of the extraction procedures, on which depends the nature of the antioxidant composition, and highlights interest to proceed with in vitro/ex vivo assay selection for the evaluation of the antioxidant properties of botanical extracts.

      • Poster Session : PS 0323 ; Hematology : Apixaban as a Therapeutic Option in Heparin-Induced Thrombocytopenia in a Patient on Hemodialysis

        ( Hector Raul Ibarra Sifuentes ),( Guillermo Ruben Garcia Delgado ),( Roberto Monreal Robles ),( Daniel Gallegos Arguijo ),( Perla Rocio Colunga Pedraza ),( Luis Javier Marfil Rivera ) 대한내과학회 2014 대한내과학회 추계학술대회 Vol.2014 No.1

        A 50-years-old woman came to the emergency room due to uremic syndrome; she was referred to start renal replacement therapy. Her past medical history was signifi - cant for long-standing type 2 diabetes and hypertension (evolving over 4 years), both conditions irregularly treated. On the night of her admission, a right femoral Mahurkar catheter was placed through an ultrasonography guided technique, and hemodialysis was thus started. Unfractionated heparin (UFH) was used as a bolus at the start of the session, subcutaneous UFH was also used as thromboprophylaxis during her hospital stay. On day 4 the second hemodialysis was performed. She clinically improved after 6 days of hospitalization, and was switched from hemodialysis to peritoneal dialysis. At admission, moderate thrombocytopenia (118 K/uL) was found, which was exhaustively investigated without identifying its cause. On day 10, showed at the physical examination painful, pitting edema, and limitation in walking. Deep venous thrombosis was then diagnosed by color Doppler ultrasonography, and anticoagulation with UFH and warfarin was started. The next day platelet count (PC) fell by 67% (absolute PC: 23. 6 K/uL), so early-onset HIT was suspected. According to the 4Ts score, our patient had a high pretest probability for HIT, therefore UFH and warfarin were discontinued. Treatment options were discussed with the patient in detail; we obtained an informed consent from her, and started her on apixaban. On day 15 her PC improved to 75 K/uL; and on day 18 to 128 K/uL. A low-dose warfarin (5 mg qd) was started together with apixaban for fi ve days. The INR was maintained within the therapeutic range during her hospital stay. On day 22 apixaban was discontinued, and she continued solely on warfarin. Prior to discharge her PC was entirely recovered (231 K/uL).

      • SCIESCOPUSKCI등재

        Graphene exfoliation with supercritical fluids

        Rodolfo Morales Ibarra,Motonobu Goto,Juan Garc?a‑Serna,Saida Mayela Garc?a Montes 한국탄소학회 2021 Carbon Letters Vol.31 No.1

        Graphene is an unconventional material with a two-dimensional hexagonal crystalline array of elemental carbon atoms and outstanding properties; accordingly, a desirable objective in the line of research of graphene is the development of novel and more productive methods of synthesis, validating its properties and applications. In our exploratory research, we have effectively exfoliated graphene from graphite using supercritical fluids (water, ethanol and carbon dioxide). The exfoliated graphene was properly characterized; via scanning electron microscopy, the morphology of graphene was observed; Raman spectra confirmed the exfoliation of graphene depicting the characteristic shift towards smaller Raman number in the 2D band (2676 cm?1) compared to that of graphite (? 2700 cm?1); COMMIT; transmission electron microscopy analysis exhibited the crystalline structure of graphene attesting also the expected transparency of exfoliated layers. Graphene exfoliation from graphite by supercritical fluids promises to be a simple large-scale method for graphene production.

      • Poster Session:PS 0536 ; Nephrology : Mortality Factors Associated to Hemodialysis Patients with End Stage Renal Disease (ESRD), in a Teaching Hospital

        ( Hector Raul Ibarra Sifuentes ),( Victor Ivan Segura Huicochea ),( Perla Rocio Colunga Pedraza ),( Miguel Angel Flores Caballero ),( Jose Guadalupe Martinez Jimenez ),( Concepcion Sanchez Martinez ) 대한내과학회 2014 대한내과학회 추계학술대회 Vol.2014 No.1

        Background: Patients on hemodialysis have a death rate adjusted for age four to fi ve times higher than the general population, so early nephrology referral affects survival, also the presence of hypoalbuminemia, hyperphosphatemia, and anemia. Methods: Descriptive, observational, prospective, Unicentric Trial, involved patients with ESRD who entered the emergency area in a teaching hospital, indicating Interventional Hemodialysis (HI), which were studied for 90 days; Demographic, clinical and laboratory data were collected. Patients were followed by phone call and meeting at 30, 60 and 90 post-HI days. Statistical analysis were realized with SPSS 18 for Windows, performed descriptive statistics and survival by Kaplan-Meier was conducted. Results: In this trial were included 41 patients, mean age 50.59 years (range 17-76 years), 23 men (56.1%). The rating for nephrologist was recorded in 9 (22%). The data results were Albumin, 2.88 ± 0.57 mg/dL, phosphate, 9.48 ± 2.90 mg/dL, Hemoglobin 7.22 ± 1.42 g/dL. From the total of patients, 15 (36.6%) died within 90 days; of which 9 (60.9%) were men; Albumin levels were lower in those who died when compare with the living (2.79 vs 2.93), phosphate levels were higher when compare to living (9.97 vs 9.20); and the level of Hb was higher in those who died (7.5 vs 7.0). Survival rates at 30, 60 and 90 days were 92.7%, 85.4% and 63.4% respectively. Conclusions: Mortality found in this study is high compared with reported worldwide. When the nephrologist referral was analyzed, patients who died were the same as the number of patients without prior reference. Hypoalbuminemia and hyperphosphatemia correlate with mortality, as demonstrated in previous studies. Importantly, in our population, patients who died, had a higher hemoglobin level when compare with survivors.

      • KCI등재

        Monetary Policy and Real Currency Appreciation: A BEER Model for the Mexican Peso

        Carlos A. Ibarra 한국국제경제학회 2011 International Economic Journal Vol.25 No.1

        notable feature of the Mexican economy since the late 1980s was the persistent real appreciation of the peso. The appreciation - a key development that helps to explain Mexico's slow rate of economic growth - took place despite changes in the exchange-rate regime, yet with an unchanging focus of monetary policy on gradually reducing the inflation rate. Thus, the frequent assumption that only real-side variables (as opposed to monetary ones) have a lasting or 'long-run' effect on the real exchange may not suit the recent Mexican case. The paper presents the results of an econometric study of exchange rate determination in Mexico for the period 1990Q1-2006Q4. The study is based on the so-called BEER (Behavioral Equilibrium Exchange Rate) model, which relies on Johansen's cointegration methodology and jointly considers real-side and monetary determinants. The estimation results - in the form of two- and three-equation cointegration models - show that, controlling for the influence of real-side determinants, the peso-dollar interest differential had a statistically and economically significant long-run effect on the peso's real exchange rate.

      연관 검색어 추천

      이 검색어로 많이 본 자료

      활용도 높은 자료

      해외이동버튼