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1.
Faraday Discuss ; 183: 309-26, 2015.
Article in English | MEDLINE | ID: mdl-26534861

ABSTRACT

Recent developments in catalysts have enhanced the potential for the utilisation of carbon dioxide as a chemical feedstock. Using the appropriate energy efficient catalyst enables a range of chemical pathways leading to desirable products. In doing so, CO2 provides an economically and environmentally beneficial source of C1 feedstock, while improving the issues relating to security of supply that are associated with fossil-based feedstocks. However, the dependence on catalysts brings other supply chains into consideration, supply chains that may also have security of supply issues. The choice of chemical pathways for specific products will therefore entail an assessment not only of economic factors but also the security of supply issues for the catalysts. This is a multi-criteria decision making problem. In this paper, we present a modified 4A framework based on the framework suggested by the Asian Pacific Energy Research centre for macro-economic applications. The 4A methodology is named after the criteria used to compare alternatives: availability, acceptability, applicability and affordability. We have adapted this framework for the consideration of alternative chemical reaction processes using a micro-economic outlook. Data from a number of sources were collected and used to quantify each of the 4A criteria. A graphical representation of the assessments is used to support the decision maker in comparing alternatives. The framework not only allows for the comparison of processes but also highlights current limitations in the CCU processes. The framework presented can be used by a variety of stakeholders, including regulators, investors, and process industries, with the aim of identifying promising routes within a broader multi-criteria decision making process.

2.
Eur J Heart Fail ; 2024 May 07.
Article in English | MEDLINE | ID: mdl-38714362

ABSTRACT

AIMS: The optimal echocardiographic predictors of cardiovascular outcome in heart failure (HF) with preserved ejection fraction (HFpEF) are unknown. We aimed to identify independent echocardiographic predictors of cardiovascular outcome in patients with HFpEF. METHODS AND RESULTS: Systematic literature search of three electronic databases was conducted from date of inception until November 2022. Hazard ratios (HRs) and their 95% confidence intervals (CIs) for echocardiographic variables from multivariate prediction models for the composite primary endpoint of cardiovascular death and HF hospitalization were pooled using a random effects meta-analysis. Specific subgroup analyses were conducted for studies that enrolled patients with acute versus chronic HF, and for those studies that included E/e', pulmonary artery systolic pressure (PASP), renal function, natriuretic peptides and diuretic use in multivariate models. Forty-six studies totalling 20 056 patients with HFpEF were included. Three echocardiographic parameters emerged as independent predictors in all subgroup analyses: decreased left ventricular (LV) global longitudinal strain (HR 1.24, 95% CI 1.10-1.39 per 5% decrease), decreased left atrial (LA) reservoir strain (HR 1.30, 95% CI 1.13-1.1.50 per 5% decrease) and lower tricuspid annular plane systolic excursion (TAPSE) to PASP ratio (HR 1.17, 95% CI 1.07-1.25 per 0.1 unit decrease). Other independent echocardiographic predictors of the primary endpoint were a higher E/e', moderate to severe tricuspid regurgitation, LV mass index and LA ejection fraction, although these variables were less robust. CONCLUSIONS: Impaired LV global longitudinal strain, lower LA reservoir strain and lower TAPSE/PASP ratio predict cardiovascular death and HF hospitalization in HFpEF and are independent of filling pressures, clinical characteristics and natriuretic peptides. These echocardiographic parameters reflect key functional changes in HFpEF, and should be incorporated in future prospective risk prediction models.

3.
Ann Acad Med Singap ; 52(4): 182-189, 2023 Apr 27.
Article in English | MEDLINE | ID: mdl-38904531

ABSTRACT

Introduction: Transitional care strategies (TCS) initiated for elderly patients prior to emergency department (ED) discharge are important for ensuring effective transition to other care settings. Such strategies have been shown to reduce avoidable acute admissions. This first nationwide study is targeted at public acute hospital EDs in Singapore, and aims to characterise TCS for ED-discharged elderly patients and understand the experiences of healthcare staff in the delivery of TCS. Method: Seven key informants (KIs), one per ED, completed an online structured questionnaire and semi-structured video conference interview from 8 May to 31 August 2021. The KIs were ED specialists and an ED-trained senior staff nurse who were knowledgeable in geriatric emergency care and had contributed to at least one elder-related TCS. Field notes were compiled, transcribed, anonymised and analysed using thematic analysis. Results: All 7 EDs have TCS as "usual care" available during office hours, at no extra cost to patients. Common components of TCS include screening, evaluation with comprehensive geriatric assessment, health education and follow-up telecare. TCS implementation was facilitated by organisational support in terms of established protocols and communication platforms, training and collaboration of a multidisciplinary team, and caregiver involvement. Obstacles faced include fragmented communication between personnel, limited resources, and poor buy-in from stakeholders. Conclusion: Understanding the heterogeneous characteristics of ED-TCS at various hospitals will aid the development of service typology and identify service opportunities. Provider experiences grouped into themes help to inform future strategies for TCS implementation. More research is needed to evaluate patient outcomes and cost-effectiveness of TCS.


Subject(s)
Emergency Service, Hospital , Transitional Care , Humans , Singapore , Aged , Transitional Care/organization & administration , Patient Discharge , Male , Female , Geriatric Assessment/methods , Surveys and Questionnaires , Telemedicine
4.
PLoS One ; 17(1): e0262260, 2022.
Article in English | MEDLINE | ID: mdl-35045116

ABSTRACT

There is growing interest in the role that morphological knowledge plays in literacy acquisition, but there is no research directly comparing the efficacy of different forms of morphological instruction. Here we compare two methods of teaching English morphology in the context of a memory experiment when words were organized by affix during study (e.g., a list of words was presented that all share an affix, such as , , , , etc.) or by base during study (e.g., a list of words was presented that all share a base, such as , , , ). We show that memory for morphologically complex words is better in both conditions compared to a control condition that does not highlight the morphological composition of words, and most importantly, show that studying words in a base-centric format improves memory further still. We argue that the morphological matrix that organizes words around a common base may provide an important new tool for literacy instruction.


Subject(s)
Education/methods , Literacy/trends , Teaching/education , Education/trends , Female , Humans , Language , Linguistics/methods , Male , Reading , Young Adult
5.
Bioorg Med Chem Lett ; 20(11): 3314-21, 2010 Jun 01.
Article in English | MEDLINE | ID: mdl-20451378

ABSTRACT

Thirty-six novel acylurea connected straight chain hydroxamates were designed and synthesized. Structure-activity relationships (SAR) were established for the length of linear chain linker and substitutions on the benzoylurea group. Compounds 5g, 5i, 5n, and 19 showed 10-20-fold enhanced HDAC1 potency compared to SAHA. In general, the cellular potency pIC(50) (COLO205) correlates with enzymatic potency pIC(50) (HDAC1). Compound 5b (SB207), a structurally simple and close analogue to SAHA, is more potent against HDAC1 and HDAC6 compared to the latter. As a representative example of this series, good in vitro enzymatic and cellular potency plus an excellent pharmacokinetic profile has translated into better efficacy than SAHA in both prostate cancer (PC3) and colon cancer (HCT116) xenograft models.


Subject(s)
Histone Deacetylase Inhibitors/chemical synthesis , Histone Deacetylase Inhibitors/pharmacology , Hydroxamic Acids/pharmacology , Urea/pharmacology , Animals , Cell Line, Tumor , Histone Deacetylase Inhibitors/chemistry , Humans , Hydroxamic Acids/chemistry , Kinetics , Mice , Structure-Activity Relationship , Transplantation, Heterologous
6.
Bioorg Med Chem Lett ; 19(5): 1403-8, 2009 Mar 01.
Article in English | MEDLINE | ID: mdl-19181524

ABSTRACT

A series of N-hydroxy-1,2-disubstituted-1H-benzimidazol-5-yl acrylamides were designed and synthesized as novel HDAC inhibitors. General SAR has been established for the substituents at positions 1 and 2, as well as the importance of the ethylene group and its attachment to position 5. Optimized compounds are much more potent than SAHA in both enzymatic and cellular assays. A representative compound, 23 (SB639), has demonstrated antitumor activity in a colon cancer xenograft model.


Subject(s)
Acrylamides/chemical synthesis , Antineoplastic Agents/chemical synthesis , Benzimidazoles/chemical synthesis , Histone Deacetylase Inhibitors , Acrylamides/administration & dosage , Acrylamides/pharmacology , Animals , Antineoplastic Agents/administration & dosage , Antineoplastic Agents/pharmacology , Benzimidazoles/administration & dosage , Benzimidazoles/pharmacology , Cell Line, Tumor , Crystallography, X-Ray , Drug Screening Assays, Antitumor/methods , Female , HCT116 Cells , Histone Deacetylases/metabolism , Humans , Mice , Mice, Nude , Structure-Activity Relationship , Xenograft Model Antitumor Assays
7.
Front Psychol ; 8: 974, 2017.
Article in English | MEDLINE | ID: mdl-28676770

ABSTRACT

Spatial metaphors are used to represent and reason about time. Such metaphors are typically arranged along the sagittal axis in most languages. For example, in English, "The future lies ahead of us" and "We look back on our past." This is less straightforward for Chinese. Specifically, both the past and future can either be behind or ahead. The present study aims to explore these cross-linguistic differences by priming auditory targets (e.g., tomorrow) with either a congruent (i.e., pointing forwards) or incongruent (i.e., pointing backwards) gesture. Two groups of college-age young adult participants (English and Chinese speakers) made temporal classifications of words after watching a gestural prime. If speakers represent time along the sagittal axis, they should respond faster if the auditory target is preceded with a gesture indicating a congruent vs. incongruent spatial location. Results showed that English speakers responded faster to congruent gesture-word pairs than to incongruent pairs, mirroring spatio-temporal metaphors commonly recruited to talk about time in their native language. However, such an effect of congruency was not found for Chinese speakers. These findings suggest that while the spatio-temporal metaphors commonly recruited to talk about time help to structure the mental timelines of English speakers, the varying instances in how time is represented along the sagittal axis in Chinese may lead to a more variable mental timeline as well. In addition, our findings demonstrate that gestures may not only be a means of accessing concrete concepts in the mind, as shown in previous studies, but may be used to access abstract ones as well.

8.
Front Psychol ; 7: 976, 2016.
Article in English | MEDLINE | ID: mdl-27445936

ABSTRACT

A large number of studies have demonstrated that semantic richness dimensions [e.g., number of features, semantic neighborhood density, semantic diversity , concreteness, emotional valence] influence word recognition processes. Some of these richness effects appear to be task-general, while others have been found to vary across tasks. Importantly, almost all of these findings have been found in the visual word recognition literature. To address this gap, we examined the extent to which these semantic richness effects are also found in spoken word recognition, using a megastudy approach that allows for an examination of the relative contribution of the various semantic properties to performance in two tasks: lexical decision, and semantic categorization. The results show that concreteness, valence, and number of features accounted for unique variance in latencies across both tasks in a similar direction-faster responses for spoken words that were concrete, emotionally valenced, and with a high number of features-while arousal, semantic neighborhood density, and semantic diversity did not influence latencies. Implications for spoken word recognition processes are discussed.

9.
J Med Chem ; 54(13): 4694-720, 2011 Jul 14.
Article in English | MEDLINE | ID: mdl-21634430

ABSTRACT

A series of 3-(1,2-disubstituted-1H-benzimidazol-5-yl)-N-hydroxyacrylamides (1) were designed and synthesized as HDAC inhibitors. Extensive SARs have been established for in vitro potency (HDAC1 enzyme and COLO 205 cellular IC(50)), liver microsomal stability (t(1/2)), cytochrome P450 inhibitory (3A4 IC(50)), and clogP, among others. These parameters were fine-tuned by carefully adjusting the substituents at positions 1 and 2 of the benzimidazole ring. After comprehensive in vitro and in vivo profiling of the selected compounds, SB939 (3) was identified as a preclinical development candidate. 3 is a potent pan-HDAC inhibitor with excellent druglike properties, is highly efficacious in in vivo tumor models (HCT-116, PC-3, A2780, MV4-11, Ramos), and has high and dose-proportional oral exposures and very good ADME, safety, and pharmaceutical properties. When orally dosed to tumor-bearing mice, 3 is enriched in tumor tissue which may contribute to its potent antitumor activity and prolonged duration of action. 3 is currently being tested in phase I and phase II clinical trials.


Subject(s)
Antineoplastic Agents/chemical synthesis , Benzimidazoles/chemical synthesis , Histone Deacetylase Inhibitors/chemical synthesis , Administration, Oral , Animals , Antineoplastic Agents/pharmacokinetics , Antineoplastic Agents/pharmacology , Benzimidazoles/pharmacokinetics , Benzimidazoles/pharmacology , Biological Availability , Cell Line, Tumor , Dogs , Drug Screening Assays, Antitumor , Female , Histone Deacetylase 1/antagonists & inhibitors , Histone Deacetylase Inhibitors/pharmacokinetics , Histone Deacetylase Inhibitors/pharmacology , Humans , Isoenzymes/antagonists & inhibitors , Isoenzymes/metabolism , Mice , Mice, Inbred BALB C , Mice, Nude , Microsomes, Liver/metabolism , Neoplasm Transplantation , Quantitative Structure-Activity Relationship , Rats , Rats, Wistar , Stereoisomerism
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