The colonic microbiota ferment dietary fibres, producing short chain fatty acids. Recent evidence suggests that the short chain fatty acid propionate may play an important role in appetite ...regulation. We hypothesised that colonic delivery of propionate would increase peptide YY (PYY) and glucagon like peptide-1 (GLP-1) secretion in humans, and reduce energy intake and weight gain in overweight adults.
To investigate whether propionate promotes PYY and GLP-1 secretion, a primary cultured human colonic cell model was developed. To deliver propionate specifically to the colon, we developed a novel inulin-propionate ester. An acute randomised, controlled cross-over study was used to assess the effects of this inulin-propionate ester on energy intake and plasma PYY and GLP-1 concentrations. The long-term effects of inulin-propionate ester on weight gain were subsequently assessed in a randomised, controlled 24-week study involving 60 overweight adults.
Propionate significantly stimulated the release of PYY and GLP-1 from human colonic cells. Acute ingestion of 10 g inulin-propionate ester significantly increased postprandial plasma PYY and GLP-1 and reduced energy intake. Over 24 weeks, 10 g/day inulin-propionate ester supplementation significantly reduced weight gain, intra-abdominal adipose tissue distribution, intrahepatocellular lipid content and prevented the deterioration in insulin sensitivity observed in the inulin-control group.
These data demonstrate for the first time that increasing colonic propionate prevents weight gain in overweight adult humans.
NCT00750438.
The rise of e‐commerce over the past 20 years has created an increased need for responsive omnichannel distribution to meet the last mile challenge. Some companies are experimenting with the use of ...the sharing economy business model to augment distribution strategies. The use of so‐called “Crowdsourced Logistics” (CSL) is becoming more prevalent in practice, but the role in logistics strategy of this new phenomenon has not been thoroughly investigated and understood. Using a contingency theory lens, this research contributes a nascent understanding of how CSL performs in terms of logistics effectiveness by simulating same‐day delivery services from a distribution center to 1,000 customer locations throughout New York City under dynamic market conditions and by comparing the results to those of a traditional dedicated fleet of delivery drivers. The findings are analyzed to suggest how firms may find strategic benefit using CSL. An agenda for future research is provided to explore these strategic implications and to deepen knowledge about the CSL phenomenon.
Summary
Competition between microbial species is a product of, yet can lead to a reduction in, the microbial diversity of specific habitats. Microbial habitats can resemble ecological battlefields ...where microbial cells struggle to dominate and/or annihilate each other and we explore the hypothesis that (like plant weeds) some microbes are genetically hard‐wired to behave in a vigorous and ecologically aggressive manner. These ‘microbial weeds’ are able to dominate the communities that develop in fertile but uncolonized – or at least partially vacant – habitats via traits enabling them to out‐grow competitors; robust tolerances to habitat‐relevant stress parameters and highly efficient energy‐generation systems; avoidance of or resistance to viral infection, predation and grazers; potent antimicrobial systems; and exceptional abilities to sequester and store resources. In addition, those associated with nutritionally complex habitats are extraordinarily versatile in their utilization of diverse substrates. Weed species typically deploy multiple types of antimicrobial including toxins; volatile organic compounds that act as either hydrophobic or highly chaotropic stressors; biosurfactants; organic acids; and moderately chaotropic solutes that are produced in bulk quantities (e.g. acetone, ethanol). Whereas ability to dominate communities is habitat‐specific we suggest that some microbial species are archetypal weeds including generalists such as: Pichia anomala, Acinetobacter spp. and Pseudomonas putida; specialists such as Dunaliella salina, Saccharomyces cerevisiae, Lactobacillus spp. and other lactic acid bacteria; freshwater autotrophs Gonyostomum semen and Microcystis aeruginosa; obligate anaerobes such as Clostridium acetobutylicum; facultative pathogens such as Rhodotorula mucilaginosa, Pantoea ananatis and Pseudomonas aeruginosa; and other extremotolerant and extremophilic microbes such as Aspergillus spp., Salinibacter ruber and Haloquadratum walsbyi. Some microbes, such as Escherichia coli, Mycobacterium smegmatis and Pseudoxylaria spp., exhibit characteristics of both weed and non‐weed species. We propose that the concept of nonweeds represents a ‘dustbin’ group that includes species such as Synodropsis spp., Polypaecilum pisce, Metschnikowia orientalis, Salmonella spp., and Caulobacter crescentus. We show that microbial weeds are conceptually distinct from plant weeds, microbial copiotrophs, r‐strategists, and other ecophysiological groups of microorganism. Microbial weed species are unlikely to emerge from stationary‐phase or other types of closed communities; it is open habitats that select for weed phenotypes. Specific characteristics that are common to diverse types of open habitat are identified, and implications of weed biology and open‐habitat ecology are discussed in the context of further studies needed in the fields of environmental and applied microbiology.
This article explores the ecology, and cellular and molecular traits, of a select number of microbial species that consistently dominate their respective habitats. We suggest that these ‘microbial weeds’ have key features in common with plant weeds, and are conceptually distinct from other groupings of microorganisms such as generalists, specialists, copiotrophs, oligotrophs, r‐strategists, K‐strategists, etc. Microbial weed species are most likely to emerge in open habitats; we describe and give examples of such habitats and discuss environmental and applied implications of weed biology and open‐habitat ecology as well as further work needed in these areas.
Objectives
To compare the FRAIL‐NH scale with the Frailty Index in assessing frailty in residential aged care facilities.
Design
Cross‐sectional.
Setting
Six Australian residential aged care ...facilities.
Participants
Individuals aged 65 and older (N = 383, mean aged 87.5 ± 6.2, 77.5% female).
Measurements
Frailty was assessed using the 66‐item Frailty Index and the FRAIL‐NH scale. Other measures examined were dementia diagnosis, level of care, resident satisfaction with care, nurse‐reported resident quality of life, neuropsychiatric symptoms, and professional caregiver burden.
Results
The FRAIL‐NH scale was significantly associated with the Frailty Index (correlation coefficient = 0.81, P < .001). Based on the Frailty Index, 60.8% of participants were categorized as frail and 24.4% as most frail. Based on the FRAIL‐NH, 37.5% of participants were classified as frail and 35.9% as most frail. Women were assessed as being frailer than men using both tools (P = .006 for FI; P = .03 for FRAIL‐NH). Frailty Index levels were higher in participants aged 95 and older (0.39 ± 0.13) than in those aged younger than 85 (0.33 ± 0.13; P = .008) and in participants born outside Australia (0.38 ± 0.13) than in those born in Australia (0.34 ± 0.13; P = .01). Both frailty tools were associated with most characteristics that would indicate higher care needs, with the Frailty Index having stronger associations with all of these measures.
Conclusion
The FRAIL‐NH scale is a simple and practical method to screen for frailty in residential aged care facilities.
Low bulk diffusivity inside viscous semisolid atmospheric secondary organic aerosol (SOA) can prolong equilibration time scale, but its broader impacts on aerosol growth and size distribution ...dynamics are poorly understood. Here, we present quantitative insights into the effects of bulk diffusivity on the growth and evaporation kinetics of SOA formed under dry conditions from photooxidation of isoprene in the presence of a bimodal aerosol consisting of Aitken (ammonium sulfate) and accumulation (isoprene or α-pinene SOA) mode particles. Aerosol composition measurements and evaporation kinetics indicate that isoprene SOA is composed of several semivolatile organic compounds (SVOCs), with some reversibly reacting to form oligomers. Model analysis shows that liquid-like bulk diffusivities can be used to fit the observed evaporation kinetics of accumulation mode particles but fail to explain the growth kinetics of bimodal aerosol by significantly under-predicting the evolution of the Aitken mode. In contrast, the semisolid scenario successfully reproduces both evaporation and growth kinetics, with the interpretation that hindered partitioning of SVOCs into large viscous particles effectively promotes the growth of smaller particles that have shorter diffusion time scales. This effect has important implications for the growth of atmospheric ultrafine particles to climatically active sizes.
Lipin/Pah phosphatidic acid phosphatases (PAPs) generate diacylglycerol to regulate triglyceride synthesis and cellular signaling. Inactivating mutations cause rhabdomyolysis, autoinflammatory ...disease, and aberrant fat storage. Disease-mutations cluster within the conserved N-Lip and C-Lip regions that are separated by 500-residues in humans. To understand how the N-Lip and C-Lip combine for PAP function, we determined crystal structures of Tetrahymena thermophila Pah2 (Tt Pah2) that directly fuses the N-Lip and C-Lip. Tt Pah2 adopts a two-domain architecture where the N-Lip combines with part of the C-Lip to form an immunoglobulin-like domain and the remaining C-Lip forms a HAD-like catalytic domain. An N-Lip C-Lip fusion of mouse lipin-2 is catalytically active, which suggests mammalian lipins function with the same domain architecture as Tt Pah2. HDX-MS identifies an N-terminal amphipathic helix essential for membrane association. Disease-mutations disrupt catalysis or destabilize the protein fold. This illustrates mechanisms for lipin/Pah PAP function, membrane association, and lipin-related pathologies.
Carsharing helps mitigate transportation congestion, parking demand, as well as the environmental, and social transportation challenges in cities. Besides providing vehicle access to lower income ...households, it lowers emissions and reduces vehicle miles traveled (VMT) as well as the number of vehicles registered. Despite these benefits, carsharing systems have been slow to develop in China. Little is known about carsharing demand in China's context, and subsequent system design parameters. This paper explores potential carsharing demand, fleet size, and economic performance in Beijing. To determine these, carsharing mode split is estimated by a stated preference choice modeling exercise. Adequate fleet size is estimated through a Monte Carlo simulation that includes factors such as vehicle types (electric or gasoline vehicle), charger types for electric vehicles (level 2 or level 3 chargers) that influence charging time, arrival rates, travel distance, and travel time based on the time intervals (peak or non-peak hours). In addition, this study estimates the payback period to recover sunk costs. Results indicate that the carsharing mode split ranges from 9% to 32% and an electric vehicle fleet with level 2 chargers is more appropriate for carsharing in Beijing.
This study aims to understand the spatiotemporal changes in patterns of tropical crop cultivation in Eastern Thailand, encompassing the periods before, during, and after the COVID-19 pandemic. Our ...approach involved assessing the efficacy of high-resolution (10 m) Sentinel-2 dense image time series for mapping smallholder farmlands. We integrated harmonic regression and random forest to map a diverse array of tropical crop types between summer 2017 and summer 2023, including durian, rice, rubber, eucalyptus, oil palm, pineapple, sugarcane, cassava, mangosteen, coconut, and other crops. The results revealed an overall mapping accuracy of 85.6%, with several crop types exceeding 90%. High-resolution imagery demonstrated particular effectiveness in situations involving intercropping, a popular practice of simultaneously growing two or more plant species in the same patch of land. However, we observed overestimation in the majority of the studied cash crops, primarily those located in young plantations with open tree canopies and grass-covered ground surfaces. The adverse effects of the COVID-19 pandemic were observed in specific labor-intensive crops, including rubber and durian, but were limited to the short term. No discernible impact was noted across the entirety of the study timeframe. In comparison, financial gain and climate change appeared to be more pivotal in influencing farmers’ decisions regarding crop cultivation. Traditionally dominant crops such as rice and oil palm have witnessed a discernible decline in cultivation, reflecting a decade-long trend of price drops preceding the pandemic. Conversely, Thai durian has seen a significant upswing even over the pandemic, which ironically served as a catalyst prompting Thai farmers to adopt e-commerce to meet the surging demand, particularly from China.
Crowdsourcing technology platforms specializing in on‐demand last mile delivery face a novel problem—heightened agent independence increases uncertainty in last mile delivery and has the potential to ...undermine operational performance. Uncertainty emanates from drivers' competing interests, or opportunity costs. Rather than increase remuneration, some platforms have designed the technology to allow customers to tip, but the subsequent effects on driver behavior and last mile performance have not yet been studied. We explore this feature of on‐demand delivery technology design—customer tipping—and its implications for crowdsourced delivery performance. Using netnography and secondary data sources, we empirically ground an adaptive, multi‐agent hybrid simulation to propose how customer tipping impacts service performance through context‐contingent driver behavior. Our results generally indicate that tipping as a technology design feature mitigates uncertainty in the crowdsourced delivery fleet and reduces fulfillment times and unit delivery costs. We also find evidence suggesting that the impact of tipping on driver behavior is geography‐contingent, with tipping having unexpectedly detrimental effects in high population density areas relative to low‐density areas. We conclude by making a series of theoretical propositions and managerial implications about designing technology to facilitate crowdsourced delivery.
Being the lifeblood of socioeconomic progress, engineering is implicated in the unprecedented challenge of sustainability. The global engineering community devised sustainable engineering as a ...conceptual departure from conventional engineering practices. However, the extent to which the sustainability worldview has permeated the Nigerian engineering community remains unanswered. This paper is an attempt to answer the question of how sustainability literate are the members of the Nigerian engineering community. The paper undertakes an assessment of the sustainability literacy of the community with the aid of a stakeholder survey and a devised sustainability literacy test. Three criteria that are used to gauge the stakeholders’ sustainability literacy are awareness of the UN Decade of Education for Sustainable Development, score on the sustainability literacy test, and self-assessment of sustainability knowledge. Survey participants were recruited mainly from two federally-run Nigerian higher education institutions, and engineering professional associations. The assessment reveals an unsatisfactory performance of the Nigerian engineering stakeholders on all three sustainability literacy criteria. The results show that the majority of the students (81%), educators (67%), and practitioners (64%) were unaware of the UNDESD. The paper therefore highlights the need to improve the sustainability literacy of the Nigerian engineering community, possibly through a sustainability education intervention.
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