Ramos M.,Institute Ingenieria y Tecnologia |
Ramos M.,University of Texas at El Paso |
Ferrer D.,University of Texas at Austin |
Martinez-Soto E.,University Metropolitana |
And 4 more authors.
Ultramicroscopy | Year: 2013
Hydrotreatment catalytic operations are commonly performed industrially by layered molybdenum sulfide promoted by cobalt or nickel in order to remove heteroelements (S, N, O) from fossil fuels and biofuels. Indeed, these heteroelements are responsible of the emission of pollutants when these fuels are used in vehicles. In this respect, previous studies made by our research group have shown that the active phase under steady state conditions is partially carbided while strong bending effects of MoS2 slabs were also observed. However, up to now, the morphology of the resulting Co/MoSxCy carbided catalyst has not been fully characterized. In the present study, for the first time, a chemical reaction between the carbon content of a TEM Cu/C grid and a freshly sulfide Co/MoS2 catalyst was in situ observed at 300°C and 450°C by HRTEM experimental techniques at ~10nm of resolution. Results indicate that bending of MoS2 layers occurred due to carbon addition on MoS2 edge sites, as observed in stabilized catalysts after HDS reaction. Using a silicon grid, only cracks of MoS2 slabs were observed without bending effect confirming the role of structural-carbon in this change of morphology. © 2012 Elsevier B.V.
Malhotra S.V.,Frederick National Laboratory for Cancer Research |
Kumar V.,Frederick National Laboratory for Cancer Research |
Velez C.,University Metropolitana |
Zayas B.,University Metropolitana
MedChemComm | Year: 2014
A study of the effects of imidazolium-based ionic liquids on 60 human cancer cell lines representing diverse histologies has identified four compounds which show potency at a nanomolar dose. Their effects on annexin V, DNA fragmentation, and the cell cycle, together with mitochondrial membrane permeabilization tests, provide insights into their mechanism of action. Also, experiments with A431 human epidermoid carcinoma cells suggest the activation of an apoptotic pathway, due to activity of the initiator caspase 8 and effector caspase 3. © 2014 the Partner Organisations.
Agency: NSF | Branch: Standard Grant | Program: | Phase: ADVANCED TECH EDUCATION PROG | Award Amount: 501.82K | Year: 2010
This project establishes a partnership between the Universidad Metropolitana (UMET), the Institutos Tecnologicos de Puerto Rico (ITPR) and representatives from businesses in Puerto Rico with a need for employees with 2-year and 4-year technical degrees in instrumentation, automation and control. The project is improving the science and mathematics education on two campuses of ITPR in order to produce more qualified instrumentation technicians for local industry and to facilitate the matriculation of ITPR graduates to four-year programs at UMET. The laboratory facilities on two ITPR campuses are being upgraded and the faculty are receiving professional development in math and science content and modern pedagogical techniques. UMET is implementing a new bachelors of science degree in instrumentation, automation and control. The curriculum of the new degree is being developed in conjunction with ITPR and includes articulation agreements. The new degree makes extensive use of a state-of-the-art instrumentation and process control laboratory. The project includes rigorous formative and summative evaluation plans with both qualitative and quantitative components coordinated by an independent evaluator. The project results are being disseminated through conference and journal publications with a targeted effort to reach other Hispanic serving institutions.
Agency: NSF | Branch: Continuing grant | Program: | Phase: | Award Amount: 450.00K | Year: 2013
This REU Site is co-funded by the Department of Defense in partnership with the NSF REU program. This award supports a Research Experience for Undergraduates (REU) Site led by Professors Osvaldo Cox and Beatriz Zayas both at Universidad Metropolitana in San Juan, Puerto Rico. The REU Site is located at four campuses of the University of Puerto Rico and the Arecibo Observatory. The research projects supported at these Sites entitled, Research Training in Cross-disciplinary Chemical Sciences will engage disadvantaged Hispanic STEM students and will to bring together five institutions and a multidisciplinary mentoring team to increase the research competitiveness of these chemistry students and improve their numbers in the STEM pipeline in the chemical sciences.
This REU Site anticipates an increase in chemistry majors who will experience research competitiveness, gain confidence, and develop an interest in graduate schools, as well as become professionals who are prepared to enter the STEM workforce. This REU will also benefit the entire community of chemistry students at UMET who can also participate in the REU developmental activities during the academic year. It brings together five institutions and a mentoring team who will increase the research competitiveness of these students and positively impact the STEM pipeline in the chemical sciences.
Agency: NSF | Branch: Continuing grant | Program: | Phase: | Award Amount: 2.60M | Year: 2010
The investigators will create a Global Scale Ionospheric Plasma laboratory by acquiring an Advanced Modular Incoherent Scatter Radar (AMISR) to be deployed at the Institute of Radio Astronomy in La Plata, Argentina. The field of view of the radar at the selected site in Argentina includes the magnetically conjugate point to the Arecibo Observatory in Puerto Rico. The research instrument will be called the Argentine Ionospheric Radar Experiment Station (AIRES) which, together with the Arecibo Observatory, will be able to perform inter-hemispheric measurements of the Earths ionosphere. The Arecibo ISR is part of the National Astronomy and Ionosphere Center (NAIC), a national research center operated by Cornell University. An ionospheric heating facility will shortly become operational at Arecibo to enable active ionospheric experiments using the incoherent scatter radars at Arecibo and Argentina to make diagnostic measurements. The objectives of this program are: 1) support the acquisition of a state-of-the-art instrumentation that improves access to, and increased use of, modern research and research training instrumentation by scientists, engineers, and undergraduate and graduate students; 2) To implement a research training program in Argentina in science, technology, engineering and mathematics (STEM) fields mainly in Astronomy and Atmospheric Science for graduate and undergraduate pre-college students as well as science teachers; and 3) to enhance and support research in Atmospheric Science and Planetary Science using both the proposed AIRES and the Arecibo Observatory facilities. This Global Scale Ionospheric Plasma laboratory will provide unique measurements of ionospheric properties in the heater interaction volume, as well as never-before-attempted conjugate observations of the undisturbed ionosphere. These will support a wide range of studies, including the physics of atmospheric waves and layers, and low-latitude plasma instabilities and irregularities. The installed system will bring state-of-the-art radar technology to Puerto Rico, U.S. and Argentinean Universities, with accessibility tools that make it readily available to students from many research communities. The results of the project will be disseminated through peer-reviewed journals, conferences, meetings, and publications, as well as through the organization of international schools both in Puerto Rico and Argentina.
Agency: NSF | Branch: Continuing grant | Program: | Phase: SPECIAL PROGRAMS IN ASTRONOMY | Award Amount: 107.02K | Year: 2016
Arecibo Observatory (AO) will host a summer Research Experiences for Undergraduates (REU) site in Puerto Rico. Undergraduates from across the country will be guided by AO staff as they complete research projects in radio astronomy, planetary science, atmospheric science, and in the supporting engineering and computing applications. They will also participate in scientific seminars and professional development programs. Students from the mainland will be exposed to the Puerto Rican culture and natural history through field trips and social activities. A special effort will be made to recruit qualified Puerto Rican students, who are underrepresented within STEM fields. The program includes local science teachers through a Research Experiences for Teachers program.
The main activity for all summer interns is to work on an original research project closely supervised by a staff member. Each participating mentor designs one or more well-defined projects that a student should be able to complete over a ten-week period. Projects may be either self-contained or form a part of a larger endeavor. Observatory staff give an introductory Summer Student Lecture series designed to introduce the students to the fundamental concepts of the science pursued at Arecibo and to the underlying methods employed in their research areas. Throughout the program, science seminars by staff and visiting scientists are also provided to broaden the scientific horizons of the students. As part of their program, students are strongly encouraged to attend a relevant scientific or technical meeting.
Agency: NSF | Branch: Standard Grant | Program: | Phase: | Award Amount: 137.49K | Year: 2012
In the proposed project, Universidad Metropolitana and the University of Maryland Baltimore County will conduct a pilot workshop that will bring together noted experts from several communities, including the ADVANCE community, the NSF and gender studies researchers to broaden the professional and mentoring networks of Latina postdoctoral fellows and junior faculty. These institutions have a longstanding partnership in increasing the number of underrepresented minority students who earn the doctoral degree that dates back to 2003. However, since 2007, this partnership has been formalized through a memorandum of understanding that includes a focus on collaborations among faculty at both institutions. It is expected that the pilot workshop will provide a foundation upon which more meaningful and deliberate investigation of Hispanic women in the academic STEM disciplines can be examined. The workshop is characterized by relevant plenary and group breakout sessions that will provide attendees with the opportunity to better define the course of study on Latina STEM faculty and determine pathways to broader and future emphases as it relates to this target population.
Agency: NSF | Branch: Standard Grant | Program: | Phase: | Award Amount: 658.05K | Year: 2011
The investigators will acquire a state-of-the-art laser transmitter for the potassium Doppler resonance lidar at the Arecibo Observatory. This will replace the current transmitter, which is almost 15 years old and is difficult to maintain. The purpose of the upgrade is to 1) enhance upper-mesospheric research activities using new laser technology at Arecibo, 2) improve data quality, system reliability, and increased access to and training in the use of modern research instrumentation by scientists, engineers, and graduate and undergraduate students, and 3) implement a research training program in science, technology, engineering and mathematics (STEM) fields in optics with an emphasis on atmospheric remote sensing for students from pre-college through graduate school and science teachers from Puerto Rico at Universidad Metropolitanas Puerto Rico Optical Sciences Institute (PROptScI). The improved performance of the lidar will enhance the accuracy and precision of its measurements of potassium density and temperature and ultimately enable the measurement of winds in the mesosphere and lower thermosphere (MLT). When coupled with the ionospheric radar, the improved lidar will lead to around-the-clock measurements of MLT temperatures and winds, and daytime atmospheric air densities. The acquisition will create new synergy between the Arecibo Observatory and a majority-Hispanic university. Undergraduates from UMET will have the opportunity to participate in and learn the details of middle atmosphere research using state-of-the-art electro-optic technologies. These students will become leaders in their chosen careers because of the unique opportunities presented by this partnership. UMET will partner with the CRRL/CTC to develop lidar technologies and train undergraduate and graduate students who will be the next generation of lidar scientists.
Agency: NSF | Branch: Continuing grant | Program: | Phase: SPECIAL PROGRAMS IN ASTRONOMY | Award Amount: 382.88K | Year: 2013
The project will support a Research Experience for Undergraduates Site at the Arecibo Observatory in Puerto Rico, which hosts the worlds largest single-aperture radio telescope. Nine undergraduates and one high-school teacher per year will perform research in two principal areas: radio astronomy, and space and atmospheric sciences. Through a wide variety of research projects, students will be exposed to topics that include pulsars, extragalactic astronomy, near-earth asteroids, the Earths atmosphere and ionosphere, as well as gravitational waves. The will also educate its participants in cutting-edge topics and techniques through an extensive program of lectures, workshops, and site tours.
The Site will recruit from both Puerto Rico and the rest of the United States. A substantial number of its participants will be from Puerto Rico, which represents a minority community that is underrepresented in STEM fields. Numerous formal and informal cultural activities will further engender a spirit of collaboration between students from a wide variety of backgrounds. Finally, the project will strengthen the partnership between the Arecibo Observatory and the Jicamarca Radio Observatory (JRO) in Peru by sending two students to perform summer research at JRO.
This project is jointly funded by the Division of Astronomical Sciences, the Office of the Experimental Program to Stimulate Competitive Research (EPSCoR), and the Division of Atmospheric and Geospace Sciences.
PubMed | University Metropolitana, American Science and Technology, Central University of the Caribbean and University of Puerto Rico at San Juan
Type: Journal Article | Journal: Bioorganic & medicinal chemistry letters | Year: 2015
The first synthesis of C5-curcumin-fatty acid (C5-Curc-FA) conjugates was successfully performed. Through a two-step synthetic route, 10 analogs were synthesized for a structure-activity relationship (SAR) study. It was found that C5-Curc-FA conjugates containing either decanoic acid or palmitic acid moieties were cytotoxic against colorectal adenocarcinoma cell (CCL-229) at IC50s ranging from 22.5 to 56.1g/mL, being 5c the most active C5-Curc-FA conjugate. Our results strongly suggests that a decanoic acid moiety at the meta position in C5-Curc-FA conjugates is important for their anticancer activity effect. Possible mechanisms for the anticancer activity of C5-Curc-FA conjugates were also investigated including apoptosis induction, mitochondrial damage and caspases activation. It was shown that 5c inhibited the luminescence activity of NFB, a key signaling molecule involved in cell apoptosis and cell proliferation, at IC50=18.2g/mL. In addition, it was demonstrated that 5c displayed significant apoptotic effect at GI50=46.0g/mL in colorectal adenocarcinoma cell line (ATCC CCL-222), which can be explained by the significant mitochondrial membrane permeabilization and caspases 3 and 7 activation effect of 5c. Finally, it was investigated that C5-Curc-FA conjugates can affect the replication process of cancer cells, since compounds 5c, 5e, and 6c inhibited the relaxing activity of the human DNA topoisomerase I at minimum inhibitory concentrations (MICs) that range from 50 to 250g/mL. Our results strongly support the hypothesis that the inhibition of both NFB and DNA topoisomerase I by C5-Curc-FA conjugates is associated with their anticancer activity.