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1.
J Chem Educ ; 97(4): 1073-1076, 2020 Apr 14.
Artículo en Inglés | MEDLINE | ID: mdl-32308213

RESUMEN

A demonstration was developed to introduce students to waste valorization in order to form bioplastics. Waste valorization is the process of reusing, recycling, or composting, from waste, useful products or sources of energy. In this demonstration, waste valorization is introduced by converting sour milk into a bioplastic via the addition of lemon juice upon heating. Utilizing lemon juice to perform the acidification offers a greener procedure than the traditional formaldehyde (used commercially to make galalith) and enhances the transferability in remote locations such as the Amazon Rainforest in comparison to vinegar. Students can establish connections to relevant United Nations Sustainable Development Goals (UN SDGs) by adopting a systems thinking approach. However, through this, it is noteworthy that this process is also used (particularly in the Indian subcontinent) to make paneer, a farmer cheese. While this also enables students to make a link to additional UN SDGs pertaining to "zero hunger", there is an ethical discussion to be had as to whether such a process that is utilized to feed malnourished citizens should be used to make a decorative bioplastic. As such, despite this demonstration being transferrable, instructors may consider carefully whether to utilize this resource, and, if so, to use this as an opportunity to teach the importance of ethics in science.

2.
J Chem Educ ; 96(12): 2959-2967, 2019 Dec 10.
Artículo en Inglés | MEDLINE | ID: mdl-32051645

RESUMEN

Increasing demand for chemicals worldwide, depleting resources, consumer pressure, stricter legislation, and the rising cost of waste disposal are placing increasing pressure on chemical and related industries. For any organization to survive in the current arena of growing climate change laws and regulations, and increasing public influence, the issue of sustainability must be fundamental to the way it operates. A sustainable manufacturing approach will enable economic growth to be combined with environmental and social sustainability and will be realized via collaboration between a multidisciplinary community including chemists, biologists, engineers, environmental scientists, economists, experts in management, and policy makers. Hence, employees with new skills, knowledge, and experience are essential. To realize this approach, the design and development of a series of workshops encompassing systems thinking are presented here. After close consultation with industry, an annual program of interactive workshops has been designed for graduate students to go beyond examining the "greening" of chemical reactions, processes, and products, and instead embed a systems thinking approach to learning. The workshops provide a valuable insight into the issues surrounding sustainable manufacturing covering change management, commercialization, environmental impact, circular economy, legislation, and bioresources incorporating the conversion of waste into valuable products. The multidisciplinary course content incorporates industrial case studies, providing access to real business issues, and is delivered by experts from academic departments across campus and industry.

3.
J Chem Educ ; 96(12): 3006-3013, 2019 Dec 10.
Artículo en Inglés | MEDLINE | ID: mdl-32051646

RESUMEN

Green Machine is a competitive strategy card game facilitating a systems thinking approach to learning recycling processes and green chemistry in accordance with the United Nations Sustainable Development Goals. Players compete to be the first to be able to launch their recycling plant by collecting a series of playing cards. Players must use interpersonal skills to consider the interconnected systems while showing an appreciation for commercial awareness and versatility, as dynamic problem solving (reflecting real-world scenarios) is required to play the game successfully. The card game was implemented with 19 U.K. graduate students and 29 U.S. second-year undergraduate students. Survey feedback showed that Green Machine was an innovative resource that was enjoyable to play and engaged students in learning recycling processes through systems thinking. On the basis of pre- and post-test questions to evaluate learning gain, Green Machine is a helpful resource to introduce students not only to green chemistry and sustainability but also to taking a systems thinking approach to learning.

4.
J Am Soc Mass Spectrom ; 23(5): 850-7, 2012 May.
Artículo en Inglés | MEDLINE | ID: mdl-22290485

RESUMEN

LC ESI FTICR MS of a sample of cediranib identified this pharmaceutical target molecule plus an additional 10 compounds of interest, all of which were less than 10% total ion current (TIC) peak intensity relative to cediranib. LC FTICR tandem mass spectrometry using electron induced dissociation (EID) has been achieved and has proven to be the best way to generate useful product ion information for all of these singly protonated molecules. Cediranib [M + H](+) fragmented by EID to give 29 product ions whereas QTOF-CID generated only one very intense product ion, and linear ion trap-CID, which generated 10 product ions, but all with poor S/N. Twenty-six of the EID product ions were unique to this fragmentation technique alone. By considering the complementary LC-EID and LC-CID data together, all 10 unknown compounds were structurally characterized and proven to be analogous to cediranib. Of particular importance, EID produced unique product ion information for one of the low level cediranib analogues that enabled full characterization of the molecule such that the presence of an extra propylpyrrolidine group was discovered and proven to be located on the pyrrolidine ring of cediranib, solving an analytical problem that could not be solved by collision induced dissociation (CID). Thus, it has been demonstrated that EID is in harmony with the chromatography duty-cycle and the dynamic concentration range of synthetic compounds containing trace impurities, providing crucial analytical information that cannot be obtained by more traditional methodologies.


Asunto(s)
Cromatografía Liquida/métodos , Modelos Químicos , Preparaciones Farmacéuticas/química , Espectrometría de Masas en Tándem/métodos , Química Orgánica/métodos , Relación Señal-Ruido
5.
Liver Transpl ; 11(12): 1563-6, 2005 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-16315312

RESUMEN

Previous case series have reported serious complications of chicken pox (CP) after pediatric liver transplantation (PLT), mainly due to visceral dissemination. The goal of our study was to determine the incidence, risk factors, and outcomes of CP after PLT. A case-control study of all CP infections in pediatric transplant recipients followed at our center from September 1993 to April 2004 was performed. Data were collected before and after infection and at the same time points in age-, gender-, and transplant year-matched controls. Potential risk factors prior to CP and adverse outcomes after infection were compared between cases and controls. Twenty (6.2%) developed CP at a median of 1.8 yr (0.6-4.8) after PLT. All CP infections were cutaneous, with no evidence of organ involvement. Twelve were hospitalized: 9 only to receive intravenous acyclovir and 3 stayed > or =2 weeks for other complications. Risk factors were not statistically different among cases and controls. Of the outcomes analyzed, cases were significantly more likely to develop non-CP infections within one year of CP than controls (Hazard Ratio = 12.6, 95% confidence interval = 3.1-51.7; P < 0.001). These infections were often bacterial and occurred long after CP infection. In conclusion, CP is uncommon after PLT and has a low likelihood of organ dissemination. No risk factors were identified. Some cases required prolonged hospitalizations. Close monitoring for the development of late bacterial infections is warranted.


Asunto(s)
Varicela/etiología , Trasplante de Hígado/efectos adversos , Anticuerpos Antivirales/análisis , Varicela/epidemiología , Varicela/transmisión , Niño , Preescolar , Intervalos de Confianza , Femenino , Estudios de Seguimiento , Herpesvirus Humano 3/inmunología , Humanos , Incidencia , Lactante , Masculino , Estudios Retrospectivos , Factores de Riesgo , Factores de Tiempo
6.
Liver Transpl ; 11(3): 320-5, 2005 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-15719387

RESUMEN

Prior case series have suggested that herpes zoster (HZ) after orthotopic liver transplantation (OLT) may lead to serious complications due to visceral involvement. We sought to determine the incidence, risk factors, and long term outcomes of HZ after OLT. Clinical data from September 1993 to April 2004 were collected on all cases of HZ after OLT, and at the same post-OLT time points in age, gender, and transplant-year-matched HZ-negative controls. Risk factors for HZ infection and long-term outcomes were compared between cases and controls. A total of 29 patients developed HZ at a median of 4.9 years (range .5-12.9) after OLT. All HZ infections except 1 were localized to a single dermatome. Only 8 (28%) were hospitalized and 16 (55%) were treated with oral antivirals alone. No patients developed visceral involvement or died of HZ infection. No risk factors for HZ infection were identified on multivariate analysis. Of the long-term outcomes, the estimated 10-year survival was lower (P = .05) for cases than controls. The lower survival in HZ cases was not directly attributable to HZ infection. In conclusion, this study is the largest series on HZ after OLT. HZ is neither a common nor a serious infection after OLT and can be managed with antiviral therapy with a low likelihood of visceral dissemination.


Asunto(s)
Herpes Zóster/epidemiología , Trasplante de Hígado/efectos adversos , Adolescente , Adulto , Anciano , Niño , Preescolar , Herpes Zóster/mortalidad , Humanos , Incidencia , Lactante , Trasplante de Hígado/mortalidad , Persona de Mediana Edad , Complicaciones Posoperatorias/virología , Reoperación/estadística & datos numéricos , Estudios Retrospectivos , Factores de Riesgo , Análisis de Supervivencia , Sobrevivientes , Resultado del Tratamiento
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