Volla et al examine catalytic C-C bond-forming multi-component cascade or domino reactions with regard to pushing the boundaries of complexity in asymmetric organocatalysis.
The aim of this paper is to present a comprehensive review on renewable methane fuel production through the biological route of biomethanation process from major lignocellulosic agricultural crop ...waste biomass (maize, wheat, rice and sugarcane). Global annual approximate production of major agriculture based lignocellulosic biomass has been explored. Fundamental requirements of biomethanation process have been discussed in details for optimum production of methane. The essential properties of biomass (proximate, ultimate and compositional) conscientious for quality of derived fuel have also been presented along with the pretreatment requirements for lignocellulosic biomass. Methane generation potential of the major lignocellulosic agricultural crop biomass has been explored and presented. Furthermore, the methane production potential and its energetic analysis have also been compared with the bio-ethanol productions. The overall parametric analysis involved in anaerobic digestion and alcoholic fermentation explore that methane generation from lignocellulosic agricultural crop waste biomass is more economical and environmentally beneficial way of biomass utilization in a sustainable way of energy production.
► Proposes a new maximum approximated composite marginal likelihood (MACML) approach. ► The approach is simulation-free and easy to implement. ► Can be used to accommodate spatial/social interactions ...and dependencies, panel effects, and mixing effects.
The likelihood functions of multinomial probit (MNP)-based choice models entail the evaluation of analytically-intractable integrals. As a result, such models are usually estimated using maximum simulated likelihood (MSL) techniques. Unfortunately, for many practical situations, the computational cost to ensure good asymptotic MSL estimator properties can be prohibitive and practically infeasible as the number of dimensions of integration rises. In this paper, we introduce a maximum approximate composite marginal likelihood (MACML) estimation approach for MNP models that can be applied using simple optimization software for likelihood estimation. It also represents a conceptually and pedagogically simpler procedure relative to simulation techniques, and has the advantage of substantial computational time efficiency relative to the MSL approach. The paper provides a “blueprint” for the MACML estimation for a wide variety of MNP models.
Machine learning (ML) is a burgeoning field of medicine with huge resources being applied to fuse computer science and statistics to medical problems. Proponents of ML extol its ability to deal with ...large, complex and disparate data, often found within medicine and feel that ML is the future for biomedical research, personalized medicine, computer‐aided diagnosis to significantly advance global health care. However, the concepts of ML are unfamiliar to many medical professionals and there is untapped potential in the use of ML as a research tool. In this article, we provide an overview of the theory behind ML, explore the common ML algorithms used in medicine including their pitfalls and discuss the potential future of ML in medicine.
Flavonoids: an overview Panche, A. N.; Diwan, A. D.; Chandra, S. R.
Journal of nutritional science (Cambridge),
2016, Letnik:
5
Journal Article
Recenzirano
Odprti dostop
Flavonoids, a group of natural substances with variable phenolic structures, are found in fruits, vegetables, grains, bark, roots, stems, flowers, tea and wine. These natural products are well known ...for their beneficial effects on health and efforts are being made to isolate the ingredients so called flavonoids. Flavonoids are now considered as an indispensable component in a variety of nutraceutical, pharmaceutical, medicinal and cosmetic applications. This is attributed to their anti-oxidative, anti-inflammatory, anti-mutagenic and anti-carcinogenic properties coupled with their capacity to modulate key cellular enzyme function. Research on flavonoids received an added impulse with the discovery of the low cardiovascular mortality rate and also prevention of CHD. Information on the working mechanisms of flavonoids is still not understood properly. However, it has widely been known for centuries that derivatives of plant origin possess a broad spectrum of biological activity. Current trends of research and development activities on flavonoids relate to isolation, identification, characterisation and functions of flavonoids and finally their applications on health benefits. Molecular docking and knowledge of bioinformatics are also being used to predict potential applications and manufacturing by industry. In the present review, attempts have been made to discuss the current trends of research and development on flavonoids, working mechanisms of flavonoids, flavonoid functions and applications, prediction of flavonoids as potential drugs in preventing chronic diseases and future research directions.
A bidentate chelation-assisted cobalt-catalyzed C(sp2)–H activation and annulation of benzamides and alkylidenecyclopropanes (ACPs) has been realized. The unique reactivity of organocobalt species ...led to selective migratory insertion across the more electron-rich CC bond of the ACP followed by faster reductive elimination from the seven-membered cobaltacycle leading to spiro-dihydroisoquinoline derivatives with conservation of the cyclopropyl ring. The operationally simple reaction conditions allowed the C–H activation of both aryl and heteroaryl amides at room temperature.
•A new two-stage budgeting multiple discrete-count model is proposed.•Alternative processes are identified for multivariate count choices.•Using reverse-Gumbel stochastic terms, a closed form is ...obtained.•A tourism trip generation and destination model is estimated.
In this paper, we propose a new two-stage budgeting-based utility-theoretic econometric multiple discrete-count model based on the linking of a fractional split MDCEV model component with a total count model. Through the strategic specification of error distributions in the model, we derive a multiple discrete-count extreme value (MDCNTEV) model that has a closed-form probability expression and that is estimable using straightforward maximum likelihood estimation. An application of the proposed model is demonstrated in the context of individuals’ multivariate count of recreational episodes to each of multiple possible tourism destination locations. The results highlight the promise of the proposed model for a variety of multivariate count consumer choice settings. The model can also serve as a base model over which random heterogeneity may be superimposed to specify more advanced models.
►Hydrothermal pretreatment offer accelerated pre-hydrolysis of rice straw biomass. ► 5% NaOH addition is a mandatory requirement in rice straw hydrothermal substrate. ► Methane production was ...increased by 222.0% for hydrothermal pretreated substrates. ► Hydrothermal pretreatment found as the promising method for improved biomethanation.
This paper presents the results of an experimental batch methane fermentation (at 37°C mesophilic temperature) study carried out on untreated and pretreated substrates of rice straw using NaOH and hydrothermal pretreatments. 3% NaOH pretreatment was given to ground rice straw biomass for 120h at 37°C and hydrothermal pretreatment was given for 10min at 200°C. It was observed that NaOH addition is a mandatory requirement for maintaining a suitable range of pH and starting the biogas production from hydrothermal pretreated biomass slurry of rice straw. The fed substrate concentrations were maintained at 5% TS (50g TS/L). The study revealed into 140.0L/kg VSa biogas and 59.8L/kg VSa methane from untreated rice straw substrate. However, NaOH pretreated substrate resulted into 184.8L/kg VSa biogas and 74.1L/kg VSa methane. Hydrothermal pretreated followed by 5% NaOH added substrate resulted into highest biogas and methane production yields as 315.9L/kg VSa and 132.7L/kg VSa, respectively. NaOH pretreated substrate showed an increase of 132.0% in biogas production and 123.9% in methane production relative to the untreated substrate. However, the hydrothermal pretreated substrate had resulted into an increase of 225.6% in biogas production and 222.0% in methane production relative to untreated rice straw substrate. Hydrothermal pretreatment provided an accelerated pre-hydrolysis of biomass contents during the treatment process and thereby resulted into enhanced biogas and methane production yields.
•Interest in using travel time productively is encouraging the use of ride-hailing.•Presence of strangers is less burdensome in a commute trip than in a leisure trip.•Delays are a greater barrier to ...shared rides than the actual presence of strangers.
With the era of fully automated vehicles (AVs) quickly approaching, ridesharing services could have an important role in increasing vehicle occupancy, reducing vehicle miles traveled, and improving traffic conditions. However, the extent to which these potentials can be achieved depends on consumers’ disposition to sharing rides. From a travel behavior perspective, two essential elements to the adoption of shared rides are individuals’ acceptance of increased travel times associated with pick-up/drop-off of other passengers and their approval of strangers sharing the same vehicle. The current study develops the notion of willingness to share (WTS), which represents the money value attributed by an individual to traveling alone compared to riding with strangers, to investigate the adoption of shared rides. Using a multivariate integrated choice and latent variable approach, we examine current choices and future intentions regarding the use of shared rides and estimate individuals’ WTS as well as their values of travel time for two distinct trip purposes. Results show that users are less sensitive to the presence of strangers when in a commute trip compared to a leisure-activity trip. We also observe that the travel time added to the trip to serve other passengers may be a greater barrier to the use of shared services compared to the presence of a stranger. However, the potential to use travel time productively may help overcome this barrier especially for high-income individuals.
This paper presents the results of an experimental methane fermentation study on untreated, NaOH and hydrothermal pretreated substrates of wheat straw. Experiments were conducted at 37 °C (mesophilic ...temperature). Substrates concentration were maintained at 4.45% VS (44.5 g VS/L). Untreated wheat straw substrate had resulted into specific methane and biogas production yields of 78.4 L/kg VSa and 188.4 L/kg VSa, respectively. The specific methane and biogas production yield of NaOH pretreated wheat straw substrate had resulted into 165.9 L/kg VSa and 353.2 L/kg VSa, respectively. Hydrothermal pretreated wheat straw substrate had resulted to yield specific methane and biogas production of 94.1 L/kg VSa and 205.7 L/kg VSa, respectively. NaOH pretreated substrate produced 87.5% higher biogas production and 111.6% higher methane production compared to the untreated wheat straw substrate. Hydrothermal pretreated substrate had resulted into an increase of 9.2% in biogas production and 20.0% in methane production compared to that of untreated wheat straw substrate.
► NaOH, hydrothermal pretreated substrates of wheat straw were studied for Methane fermentation. ► Minimum 5% NaOH addition is required for hydrothermal substrate to maintain a suitable pH. ► Biogas and methane production were increased by 87.5% and 111.6% for 4% NaOH pretreated substrate. ► Wheat straw NaOH pretreatment found a potential method to enhance biogas and methane production.
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