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1.
Chem Commun (Camb) ; 59(91): 13571-13574, 2023 Nov 14.
Artículo en Inglés | MEDLINE | ID: mdl-37902297

RESUMEN

The photoluminescence properties (PL) of Eu3+ hosted in the hydroxide layers of layered double hydroxides (LDHs) enables calibrationless quantification of anions in the interlayers. The concept is demonstrated during the nitrate-to-carbonate ion exchange in Zn2+/Al3+/Eu3+ LDHs and can be implemented as a remote optical sensor to detect intrusion of anions such as Cl- or CO32-.

2.
Drug Discov Today ; 28(7): 103619, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37201779

RESUMEN

In this work, process models were developed to capture the impact of biomanufacturing costs on a commercial scale and emphasize the way in which facility design and operation must balance meeting product demand while minimizing production costs. Using a scenario-based modeling approach, several facility design strategies were evaluated, including a traditional large stainless-steel facility and a small footprint, portable-on-demand (POD)-based facility. Bioprocessing platforms were compared by estimating their total production costs across different facility types and specifically illustrating how continuous bioprocessing has gained in popularity as a novel and cost-effective approach to manufacture high-quality biopharmaceuticals. The analysis showed how fluctuations in market demand have a dramatic effect on manufacturing costs and plant utilization, with far-reaching implications on the total cost to patients.


Asunto(s)
Productos Biológicos , Industria Farmacéutica , Productos Biológicos/economía , Industria Farmacéutica/economía
3.
Nanoscale ; 13(27): 11781-11792, 2021 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-34160524

RESUMEN

Synthesis of layered materials exhibiting hierarchical porosity remains challenging, but nevertheless worthwhile because it turns such solids into functional materials with high specific surface area. Using a soft-templating strategy in combination with the incorporation of 8-fold coordinated Eu3+, self-assembly of self-supported layered double hydroxide (LDH) nanotubes has been achieved. Heteromorphic equimolar substitution of Al3+ by Eu3+ in Zn2+/Al3+ LDH solids intercalated with 1,3,5-benzenetricarboxylate anions (BTC) assists precipitation of the double hydroxide layers onto the convex surface of Pluronic® P-123 worm-like micelles, yielding multilayer cylinders of BTC-intercalated LDHs. Removal of the micellar template is easily achieved by liquid extraction with methanol, yielding a network of interconnected, well-defined, self-supported, multi-walled, hollow cylindrical nanotubes. Removal of Eu3+ from the synthesis disables formation of the nanotubular morphology, but still yields LDHs containing a network of embedded mesopores, resulting in a specific surface area that is 5-fold higher as compared to standard LDHs.

4.
ACS Omega ; 5(37): 23778-23785, 2020 Sep 22.
Artículo en Inglés | MEDLINE | ID: mdl-32984697

RESUMEN

Luminescent layered double hydroxides (LDH) intercalated by isophthalate (ISO) and nitrilotriacetate (NTA) have been synthesized and characterized by powder X-ray diffraction (PXRD), extended X-ray absorption fine structure (EXAFS), elemental analysis (ICP-OES and CHN), and photoluminescence spectroscopy. While PXRD shows the successful formation of ZnAlEu LDHs, EXAFS reveals that the Eu activators are hosted in the hydroxide layers with an eightfold, oxygen-rich coordination, distinct from the sixfold coordination expected for the octahedral sites of metal cations in LDHs. This kind of coordination should locally distort the brucite-like layers. Additionally, the intercalation of ISO and NTA in the LDHs is shown to change the coordination environment around Eu compared to nitrate-intercalated ZnAlEu LDHs, which suggests that these anions directly interact with the Eu centers and/or strongly affect their coordination geometry. Finally, from the photoluminescence results, analyzed based on the Judd-Ofelt theory, it is determined that Eu is most likely in an environment with no inversion symmetry.

5.
Nat Prod Res ; 34(13): 1942-1946, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-30724587

RESUMEN

The effect of exogenous application of jasmonic acid (JA) on the concentration of main terpenes and density of glandular trichomes was investigated in the Mexican oregano, propagated from seeds from 3 localities. JA 1 mM was applied locally and to the whole plant. JA locally applied increased the number of trichomes, with a mean of 20 trichomes more with respect to the controls in plants from Tecomavaca and Zapotitlán Salinas, and significantly increased the thymol concentration by 185% systemically and 255% locally, compared to the control. JA applied to the whole plant decreased the number of trichomes and increased the concentration of caryophyllene from 0.79 to 1.7 mg g-1, and α-caryophyllene from 0.3 to 0.8 mg g-1 in plants from San Rafael with reference to water control. The results suggest a plasticity of morphologic and phytochemical responses, and a potential use of JA to improve phenolic monoterpenes and sesquiterpenes production.


Asunto(s)
Ciclopentanos/farmacología , Oxilipinas/farmacología , Terpenos/análisis , Tricomas/efectos de los fármacos , Verbenaceae/efectos de los fármacos , Lippia , México , Sesquiterpenos Monocíclicos , Monoterpenos/análisis , Origanum/efectos de los fármacos , Sesquiterpenos Policíclicos/análisis , Timol/análisis
6.
PDA J Pharm Sci Technol ; 71(3): 189-205, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-27974629

RESUMEN

In order to operate profitably under different product demand scenarios, biopharmaceutical companies must design their facilities with mass output flexibility in mind. Traditional biologics manufacturing technologies pose operational challenges in this regard due to their high costs and slow equipment turnaround times, restricting the types of products and mass quantities that can be processed. Modern plant design, however, has facilitated the development of lean and efficient bioprocessing facilities through footprint reduction and adoption of disposable and continuous manufacturing technologies. These development efforts have proven to be crucial in seeking to drastically reduce the high costs typically associated with the manufacturing of recombinant proteins. In this work, mathematical modeling is used to optimize annual production schedules for a single-product commercial facility operating with a continuous upstream and discrete batch downstream platform. Utilizing cell culture duration and volumetric productivity as process variables in the model, and annual plant throughput as the optimization objective, 3-D surface plots are created to understand the effect of process and facility design on expected mass output. The model shows that once a plant has been fully debottlenecked it is capable of processing well over a metric ton of product per year. Moreover, the analysis helped to uncover a major limiting constraint on plant performance, the stability of the neutralized viral inactivated pool, which may indicate that this should be a focus of attention during future process development efforts.LAY ABSTRACT: Biopharmaceutical process modeling can be used to design and optimize manufacturing facilities and help companies achieve a predetermined set of goals. One way to perform optimization is by making the most efficient use of process equipment in order to minimize the expenditure of capital, labor and plant resources. To that end, this paper introduces a novel mathematical algorithm used to determine the most optimal equipment scheduling configuration that maximizes the mass output for a facility producing a single product. The paper also illustrates how different scheduling arrangements can have a profound impact on the availability of plant resources, and identifies limiting constraints on the plant design. In addition, simulation data is presented using visualization techniques that aid in the interpretation of the scientific concepts discussed.


Asunto(s)
Productos Biológicos/química , Biofarmacia/normas , Industria Farmacéutica/normas , Arquitectura y Construcción de Instituciones de Salud , Preparaciones Farmacéuticas/química , Control de Calidad , Tecnología Farmacéutica/normas , Flujo de Trabajo , Técnicas de Cultivo Celular por Lotes/normas , Biofarmacia/instrumentación , Biofarmacia/métodos , Reactores Biológicos/normas , Cromatografía/normas , Composición de Medicamentos , Industria Farmacéutica/instrumentación , Industria Farmacéutica/métodos , Filtración/normas , Modelos Teóricos , Tecnología Farmacéutica/instrumentación , Tecnología Farmacéutica/métodos , Factores de Tiempo
7.
Polymers (Basel) ; 8(5)2016 Apr 29.
Artículo en Inglés | MEDLINE | ID: mdl-30979267

RESUMEN

Flocculation can be used in turbulent environments resulting in floc breakage due to shearing. The degree of re-flocculation relates directly to product quality and process efficiency. This study aimed at looking for alternatives to improve the re-flocculation ability of aggregates when polyelectrolytes (PEL) are used as flocculation agents. Moreover, because branched PEL have proved previously to lead to high flocculation efficiencies, the work presented focus on the improvement of the re-flocculation ability of branched PEL. Thus, a selection of branched polymers were used primarily as flocculation aid and after flocs break up a linear polymer was added to the system in order to improve re-flocculation. Different mixtures were tested with the objective to try to induce, during re-flocculation, complementary flocculation mechanisms, favoring the patching mechanism. Re-flocculation improved significantly with this strategy. Laser Diffraction Spectroscopy was used to monitor the flocculation and re-flocculation processes supplying information about the floc size and structure. Since inorganic materials, namely bentonite, have been widely used to improve the re-flocculation capacity of polyelectrolytes, the results of using dual polyelectrolyte systems were compared with the effect of adding bentonite to the system.

8.
Adv Child Dev Behav ; 49: 137-51, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26955926

RESUMEN

This chapter examines Peruvian Quechua children's learning by observing and pitching in. The children concentrate attentively when they observe the activities of the adults and they exercise autonomy in the context of adults' encouragement of measured behaviors while always showing respectful silence in the presence of their elders.


Asunto(s)
Atención , Comparación Transcultural , Conducta de Ayuda , Indígenas Sudamericanos/psicología , Individualismo , Autonomía Personal , Aprendizaje Social , Valores Sociales , Socialización , Adulto , Niño , Crianza del Niño , Preescolar , Femenino , Humanos , Conducta Imitativa , Lactante , Masculino , Perú , Juego e Implementos de Juego , Apoyo Social
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