Microwave convective drying (MCD) is gaining increasing interest due to its unique volumetric heating capability and ability to significantly reduce drying time and improve food quality. The main ...objective of this paper is to discuss, critically analyze and evaluate the recent advances in MCD and suggest the future directions in this field. The main focus of this paper is the mathematical modeling and experimental investigations in microwave convective drying of food materials. Recent developments in mathematical modeling of MCD is discussed and existing experimental setup and their advantages and disadvantages are discussed and analysed. Long drying time is a concern in food industries. Reductions in drying time by applying MCD compared to convection drying are calculated and discussed. It was apparent that the proper integration of mathematical modeling and experimental technique is the best way to maximize the advantages of this drying method. Although a plethora of research is being carried out on this topic, there is still need for research to develop fundamental modeling to optimize the process parameters and scale up this technology for the industrial application. Overall, the review provides an in-depth insight into the latest development of MCD and its mathematical modeling approaches and will hopefully serve to inspire future work in the field.
Increasing energy demand, especially in the transportation sector, and soaring CO2 emissions necessitate the exploitation of renewable sources of energy. Despite the large variety of new energy ...carriers, liquid hydrocarbon still appears to be the most attractive and feasible form of transportation fuel taking into account the energy density, stability and existing infrastructure. Biomass is an abundant, renewable source of energy; however, utilizing it in a cost-effective way is still a substantial challenge. Lignocellulose is composed of three major biopolymers, namely cellulose, hemicellulose and lignin. Fast pyrolysis of biomass is recognized as an efficient and feasible process to selectively convert lignocellulose into a liquid fuel-bio-oil. However bio-oil from fast pyrolysis contains a large amount of oxygen, distributed in hundreds of oxygenates. These oxygenates are the cause of many negative properties, such as low heating value, high corrosiveness, high viscosity, and instability; they also greatly limit the application of bio-oil particularly as transportation fuel. Hydrocarbons derived from biomass are most attractive because of their high energy density and compatibility with the existing infrastructure. Thus, converting lignocellulose into transportation fuels via catalytic fast pyrolysis has attracted much attention. Many studies related to catalytic fast pyrolysis of biomass have been published. The main challenge of this process is the development of active and stable catalysts that can deal with a large variety of decomposition intermediates from lignocellulose. This review starts with the current understanding of the chemistry in fast pyrolysis of lignocellulose and focuses on the development of catalysts in catalytic fast pyrolysis. Recent progress in the experimental studies on catalytic fast pyrolysis of biomass is also summarized with the emphasis on bio-oil yields and quality.
Early pregnancy loss affects ∼15% of all implantation-confirmed human conceptions. However, evolutionarily conserved molecular mechanisms that regulate self-renewal of trophoblast progenitors and ...their association with early pregnancy loss are poorly understood. Here, we provide evidence that transcription factor TEAD4 ensures survival of postimplantation mouse and human embryos by controlling self-renewal and stemness of trophoblast progenitors within the placenta primordium. In an early postimplantation mouse embryo, TEAD4 is selectively expressed in trophoblast stem cell–like progenitor cells (TSPCs), and loss of Tead4 in postimplantation mouse TSPCs impairs their self-renewal, leading to embryonic lethality before embryonic day 9.0, a developmental stage equivalent to the first trimester of human gestation. Both TEAD4 and its cofactor, yes-associated protein 1 (YAP1), are specifically expressed in cytotrophoblast (CTB) progenitors of a first-trimester human placenta. We also show that a subset of unexplained recurrent pregnancy losses (idiopathic RPLs) is associatedwith impaired TEAD4 expression in CTB progenitors. Furthermore, by establishing idiopathic RPL patientspecific human trophoblast stem cells (RPL-TSCs), we show that loss of TEAD4 is associated with defective self-renewal in RPL-TSCs and rescue of TEAD4 expression restores their self-renewal ability. Unbiased genomics studies revealed that TEAD4 directly regulates expression of key cell cycle genes in both mouse and human TSCs and establishes a conserved transcriptional program. Our findings show that TEAD4, an effector of the Hippo signaling pathway, is essential for the establishment of pregnancy in a postimplantation mammalian embryo and indicate that impairment of the Hippo signaling pathway could be a molecular cause for early human pregnancy loss.
Although physician burnout is associated with negative clinical and organizational outcomes, its economic costs are poorly understood. As a result, leaders in health care cannot properly assess the ...financial benefits of initiatives to remediate physician burnout.
To estimate burnout-associated costs related to physician turnover and physicians reducing their clinical hours at national (U.S.) and organizational levels.
Cost-consequence analysis using a mathematical model.
United States.
Simulated population of U.S. physicians.
Model inputs were estimated by using the results of contemporary published research findings and industry reports.
On a national scale, the conservative base-case model estimates that approximately $4.6 billion in costs related to physician turnover and reduced clinical hours is attributable to burnout each year in the United States. This estimate ranged from $2.6 billion to $6.3 billion in multivariate probabilistic sensitivity analyses. At an organizational level, the annual economic cost associated with burnout related to turnover and reduced clinical hours is approximately $7600 per employed physician each year.
Possibility of nonresponse bias and incomplete control of confounders in source data. Some parameters were unavailable from data and had to be extrapolated.
Together with previous evidence that burnout can effectively be reduced with moderate levels of investment, these findings suggest substantial economic value for policy and organizational expenditures for burnout reduction programs for physicians.
This paper describes the impacts of sea surface temperature (SST) rise and sea-level rise (SLR) on cyclonic storm surge flooding in western Bangladesh. A calibrated numerical hydrodynamic model was ...used to simulate surge wave propagation through the rivers and overland flooding. The model was calibrated with base condition (present climate), and then eight flooding scenarios of plausible future conditions were assessed by considering increased surge heights. Flooded area, flooding depth and surge intrusion length were computed by superimposing the predicted maximum water level information on a digital elevation model (DEM). This analysis showed that for a storm surge under 2
°C SST rise and 0.3
m SLR, flood risk area would be 15.3% greater than the present risk area and depth of flooding would increase by as much as 22.7% within 20
km from the coastline. Within the risk area, the study identified 5690
km
2 land (22% of exposed coast) as a high-risk zone (HRZ) where flooding of depth 1
m or more might occur, and people should move to nearby cyclone shelters during extreme cyclonic events. Predicted area of HRZ is 1.26 times the currently demarcated HRZ. It was estimated that 320 additional shelters are required to accommodate people in the newly identified HRZ. This information would be of value to policy and decision makers for future shelter planning and designing shelter heights.
Periodontitis is a complex inflammatory disorder of the tooth supporting structures, associated with microbial dysbiosis, and linked to a number if systemic conditions. Untreated it can result in an ...irreversible damage to the periodontal structures and eventually teeth loss. Regeneration of the lost periodontium requires an orchestration of a number of biological events on cellular and molecular level. In this context, a set of vitamins have been advocated, relying their beneficial physiological effects, to endorse the biological regenerative events of the periodontium on cellular and molecular levels. The aim of the present article is to elaborate on the question whether or not vitamins improve wound healing/regeneration, summarizing the current evidence from in vitro, animal and clinical studies, thereby shedding light on the knowledge gap in this field and highlighting future research needs. Although the present review demonstrates the current heterogeneity in the available evidence and knowledge gaps, findings suggest that vitamins, especially A, B, E, and CoQ10, as well as vitamin combinations, could exert positive attributes on the periodontal outcomes in adjunct to surgical or nonsurgical periodontal therapy.
Choice of drying methods significantly impacts the nutritive and non-nutritive compounds in fruits and vegetables. Phytochemicals such as total phenolics and total flavonoids are non-nutritive ...bioactive compounds and are found in plants which are of important value due to their antioxidant properties in minimizing the oxidation reaction. However, drying and storage conditions and duration significantly affect these important quality attributes. There is currently no review article on the impact of the drying and storage conditions on these quality attributes. Therefore, the aim of this review paper is to investigate the impact of drying methods on these important phytochemicals and their antioxidant activity on dried products during the storage period. Different drying methods cause desirable and undesirable changes to dried products both physically and chemically. It is found that during the drying process at various temperature ranges from 40 to 80 °C, chemical changes occurs which affects the phenolic and the flavonoid content of dried products to increase or decrease. The increase in antioxidant activity after drying is also due to oxidized polyphenols and Maillard reaction products. This results to changes in the antioxidant potential of the dried food product and its impact on the shelf life.
Adult multipotent stem/progenitor cells, with remarkable regenerative potential, have been isolated from various components of the human periodontium. These multipotent stem/progenitor cells include ...the periodontal ligament stem/progenitor cells (PDLSCs), stem cells from the apical papilla (SCAP), the gingival mesenchymal stem/progenitor cells (G‐MSCs), and the alveolar bone proper stem/progenitor cells (AB‐MSCs). Whereas inflammation is regarded as the reason for tissue damage, it also remains a fundamental step of any early healing process. In performing their periodontal tissue regenerative/reparative activity, periodontal stem/progenitor cells interact with their surrounding inflammatory micro‐environmental, through their expressed receptors, which could influence their fate and the outcome of any periodontal stem/progenitor cell‐mediated reparative/regenerative activity. The present review discusses the current understanding about the interaction of periodontal stem/progenitor cells with their surrounding inflammatory micro‐environment, elaborates on the inflammatory factors influencing their stemness, proliferation, migration/homing, differentiation, and immunomodulatory attributes, the possible underlying intracellular mechanisms, as well as their proposed relationship to the canonical and noncanonical Wnt pathways.
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