Thin rectangular fluidized beds enable detailed optical diagnostics providing high quality data for validating numerical simulations. Because of their lower computational costs, 2D CFD continues to ...be employed despite the high wall surface-area to bed-volume ratio characterizing this geometric setup. 2D simulations do not resolve the gas and solids flow in the third (spanwise) direction nor the true boundary condition along the front and back walls, both of which are critical because the hydrodynamics are significantly affected by the presence these walls whose surface area is often much larger than the walls modeled in 2D analyses. Through highly-resolved simulations of three independent experimental setups, we show that 2D CFD may not capture, even qualitatively, the fluidization hydrodynamics because (a) bubble rise and coalescence mechanisms along the spanwise direction are not resolved, and (b) solids momentum and energy dissipation are under-predicted, and bubble rise velocities are over-predicted, because effects of the front and back walls are not modeled. 3D simulations with suitable wall boundary conditions predict bubbling dynamics and solids mixing in excellent agreement with experimental observations without further tuning of model parameters. Overall, we recommended that 3D numerical simulations be employed to model thin lab-scale setups for model development and validation purposes.
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•2D vs. 3D CFD for lab-scale simulation using standard model & numerical parameters•2D simulations restrict bubble coalescence activity, cannot capture size distribution.•Wall retardation under-predicted in 2D simulations; faster bubbles and solids mixing•2D simulations may not capture dynamics, even qualitatively.•Recommend fine-grid 3D simulations for model development and validation
Aim of Study: The photo-neutron dose equivalents of 15 MV Elekta precise accelerators were measured for different depths in phantom, for various field sizes, at different distances from the isocenter ...in the patient plane and for various wedged fields.
Materials and Methods: Fast and thermal neutrons are measured using passive detectors such as Columbia Resin-39 and pair of thermoluminescent dosimetry (TLD) 600 and TLD 700 detector from Elekta medical linear accelerator.
Results: It is found that fast photo-neutron dose rate decreases as the depth increases, with a maximum of 0.57 ± 0.08 mSv/Gy photon dose at surface and minimum of 0.09 ± 0.02 mSv/Gy photon dose at 15 cm depth of water equivalent phantom with 10 cm backscatter. Photo neutrons decreases from 1.28 ± 0.03 mSv/Gy to 0.063 ± 0.032 when measured at isocenter and at 100 cm far from the field edge along the longitudinal direction in the patient plane. Fast and thermal neutron doses increases from 0.65 ± 0.05 mSv/Gy to 1.08 ± 0.07 mSv/Gy as the field size increases; from 5 cm × 5 cm to 30 cm × 30 cm for fast neutrons. With increase in wedge field angle from 0° to 60°, it is observed that the fast neutron dose increases from 0.42 ± 0.03 mSv/Gy to 0.95 ± 0.05 mSv/Gy.s
Conclusions: Measurements indicate the photo-neutrons at few field sizes are slightly higher than the International Electrotechnical Commission standard specifications. Photo-neutrons from Omni wedged fields are studied in details. These studies of the photo-neutron energy response will enlighten the neutron dose to radiation therapy patients and are expected to further improve radiation protection guidelines.
Hypoxia is an integral part of the tumor microenvironment, caused primarily due to rapidly multiplying tumor cells and a lack of proper blood supply. Among the major hypoxic pathways, HIF-1 ...transcription factor activation is one of the widely investigated pathways in the hypoxic tumor microenvironment (TME). HIF-1 is known to activate several adaptive reactions in response to oxygen deficiency in tumor cells. HIF-1 has two subunits, HIF-1β (constitutive) and HIF-1α (inducible). The HIF-1α expression is largely regulated via various cytokines (through PI3K-ACT-mTOR signals), which involves the cascading of several growth factors and oncogenic cascades. These events lead to the loss of cellular tumor suppressant activity through changes in the level of oxygen via oxygen-dependent and oxygen-independent pathways. The significant and crucial role of HIF in cancer progression and its underlying mechanisms have gained much attention lately among the translational researchers in the fields of cancer and biological sciences, which have enabled them to correlate these mechanisms with various other disease modalities. In the present review, we have summarized the key findings related to the role of HIF in the progression of tumors.
More than five decades have been invested in understanding glucose biosensors. Yet, this immensely versatile field has continued to gain attention from the scientific world to better understand and ...diagnose diabetes. However, such extensive work done to improve glucose sensing devices has still not yielded desirable results. Drawbacks like the necessity of the invasive finger‐pricking step and the lack of optimization of diagnostic interventions still need to be considered to improve the testing process of diabetic patients. To upgrade the glucose‐sensing devices and reduce the number of intermediary steps during glucose measurement, fourth‐generation glucose sensors (FGGS) have been introduced. These sensors, made using robust electrocatalytic copper nanostructures, improve diagnostic efficiency and cost‐effectiveness. This review aims to present the essential scientific progress in copper nanostructure‐based FGGS in the past 10 years (2010 to present). After a short introduction, we presented the working principles of these sensors. We then highlighted the importance of copper nanostructures as advanced electrode materials to develop reliable real‐time FGGS. Finally, we cover the advantages, shortcomings, and prospects for developing highly sensitive, stable, and specific FGGS.
Pancreatic cancer is one of the fatal causes of global cancer-related deaths. Although surgery and chemotherapy are standard treatment options, post-treatment outcomes often end in a poor prognosis. ...In the present study, we investigated anti-pancreatic cancer and amelioration of radiation-induced oxidative damage by crocin. Crocin is a carotenoid isolated from the dietary herb saffron, a prospect for novel leads as an anti-cancer agent. Crocin significantly reduced cell viability of BXPC3 and Capan-2 by triggering caspase signaling via the downregulation of Bcl-2. It modulated the expression of cell cycle signaling proteins P53, P21, P27, CDK2, c-MYC, Cyt-c and P38. Concomitantly, crocin treatment-induced apoptosis by inducing the release of cytochrome c from mitochondria to cytosol. Microarray analysis of the expression signature of genes induced by crocin showed a substantial number of genes involved in cell signaling pathways and checkpoints (723) are significantly affected by crocin. In mice bearing pancreatic tumors, crocin significantly reduced tumor burden without a change in body weight. Additionally, it showed significant protection against radiation-induced hepatic oxidative damage, reduced the levels of hepatic toxicity and preserved liver morphology. These findings indicate that crocin has a potential role in the treatment, prevention and management of pancreatic cancer.
Melanoma is a deadly form of malignancy and according to the World Health Organization 132,000 new cases of melanoma are diagnosed worldwide each year. Surgical resection and chemo/drug treatments ...opted for early and late stage of melanoma respectively, however detrimental post surgical and chemotherapy consequences are inevitable. Noticeably melanoma drug treatments are associated with liver injuries such as hepatitis and cholestasis which are very common. Alleviation of these clinical manifestations with better treatment options would enhance prognosis status and patients survival. Natural products which induce cytotoxicity with minimum side effects are of interest to achieve high therapeutic efficiency. In this study we investigated anti-melanoma and hepatoprotective activities of frankincense essential oil (FEO) in both
and
models. Pretreatment with FEO induce a significant (
< 0.05) dose-dependent reduction in the cell viability of mouse (B16-F10) and human melanoma (FM94) but not in the normal human epithelial melanocytes (HNEM). Immunoblot analysis showed that FEO induces down regulation of Bcl-2 and up regulation of BAX in B16-F10 cells whereas in FM94 cells FEO induced dose-dependent cleavage of caspase 3, caspase 9 and PARP. Furthermore, FEO (10 μg/ml) treatment down regulated MCL1 in a time-dependent manner in FM94 cells.
toxicity analysis reveals that weekly single dose of FEO (1200 mg/kg body weight) did not elicit detrimental effect on body weight during four weeks of experimental period. Histology of tissue sections also indicated that there were no observable histopathologic differences in the brain, heart, liver, and kidney compare to control groups. FEO (300 and 600 mg/kg body weight) treatments significantly reduced the tumor burden in C57BL/6 mice melanoma model. Acetaminophen (750 mg/kg body weight) was used to induce hepatic injury in Swiss albino mice. Pre treatment with FEO (250 and 500 mg/kg body weight) for seven days retained hematology (complete blood count), biochemical parameters (AST, ALT, ALK, total bilirubin, total protein, glucose, albumin/globulin ratio, cholesterol and triglyceride), and the level of phase I and II drug metabolizing enzymes (cytochrome P450, cytochromeb5, glutathione-S-transferase) which were obstructed by the administration of acetaminophen. Further liver histology showed that FEO treatments reversed the damages (central vein dilation, hemorrhage, and nuclei condensation) caused by acetaminophen. In conclusion, FEO elicited marked anti-melanoma in both
and
with a significant heptoprotection.
Neuropsychiatric disorders that affect the central nervous system cause considerable pressures on the health care system and have a substantial economic burden on modern societies. The present ...treatments based on available drugs are mostly ineffective and often costly. The molecular process of neuropsychiatric disorders is closely connected to modifying the genetic structures inherited or caused by damage, toxic chemicals, and some current diseases. Gene therapy is presently an experimental concept for neurological disorders. Clinical applications endeavor to alleviate the symptoms, reduce disease progression, and repair defective genes. Implementing gene therapy in inherited and acquired neurological illnesses entails the integration of several scientific disciplines, including virology, neurology, neurosurgery, molecular genetics, and immunology. Genetic manipulation has the power to minimize or cure illness by inducing genetic alterations at endogenous loci. Gene therapy that involves treating the disease by deleting, silencing, or editing defective genes and delivering genetic material to produce therapeutic molecules has excellent potential as a novel approach for treating neuropsychiatric disorders. With the recent advances in gene selection and vector design quality in targeted treatments, gene therapy could be an effective approach. This review article will investigate and report the newest and the most critical molecules and factors in neuropsychiatric disorder gene therapy. Different genome editing techniques available will be evaluated, and the review will highlight preclinical research of genome editing for neuropsychiatric disorders while also evaluating current limitations and potential strategies to overcome genome editing advancements.
Methadone therapy clinics have been recently introduced in Tanzania, aiming at reducing risk behaviors and infection rates of viral hepatitis and HIV among people who use drugs. The objective of this ...study was to estimate the prevalence, associated factors and knowledge level of these conditions among people who use drugs attending a methadone clinic in Tanzania. We enrolled 253 People who using drugs receiving Methadone therapy. Clinical data was retrospectively collected from the medical records and face-to face interviews were conducted to determine the behavioral risk factors and respondents' knowledge on viral hepatitis and HIV. An overall seroprevalence of viral hepatitis (either hepatitis B surface antigen or anti-hepatitis C virus) was 6.3%, while that of hepatitis B virus mono infection was 3.5% and anti-hepatitis C antibodies was 3.5%. Seroprevalence of HIV was 12.6%. Viral hepatitis was strongly predicted by advanced age (> 35 years) (p = 0.02) and staying at Kirumba area (p = 0.004), and HIV infection was predicted by increased age (> 37 years) (p = 0.04) and female sex (p < 0.001). Regarding the knowledge of viral hepatitis, majority of the respondents were unaware of the transmission methods and availability of hepatitis B virus vaccines and only 17% were classified as well informed (provided greater than or equai to4 correct answers out of 7 questions). Good knowledge was highly predicted by higher education level of the individual (p = 0.001). Despite the efforts to curb viral hepatitis and HIV infections through Methadone clinics, infection rates among people who use drugs are still high and the general knowledge on preventive measures is inadequate.
Bubbling dynamics and distribution of gas flow critically influence the performance of fluidized bed reactors and must be quantified accurately for their design and performance optimization. In this ...study, a new toolset called the BubbleTree toolset (BT) was developed using Python and the Visualization Tool Kit (VTK) for analyzing computational fluid dynamics simulation data and performing statistical analysis of bubbling dynamics such as their volume, location, and velocity. In addition, the BT toolset provides the capability to (a) track bubbles through coalescence and splitting events and (b) compute throughflow by integrating gas fluxes through the bubble surface. The toolkit was verified using the method of manufactured solutions as well as by comparing bubbling dynamics predictions in large-scale simulations with relevant open-source software. The BT toolset also incorporates tools for rigorous statistical analysis in selected regions of interest as well as the reactor in its entirety. The BT will be integrated with MFiX CFD simulations which will enable the fundamental investigation of gas-solids flow interaction in complex reacting particulate flows, in situ estimation of bubbling (and cluster) dynamics dependent sub-grid models and performance optimization of fluidized bed reactors using CFD-simulations.
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•Developed to analyze throughflow and reactor bypass.•Tracks bubbles in a Lagrangian fashion and records travel paths.•Provides statistics about positions, size, velocities, and flux through the surface.•No heuristics or empirical equations are used to assess throughflow.•Throughflow is rigorously derived from CFD and integrated across a bubbles surface.
Cancer is one of the major diseases that cause a high number of deaths globally. Of the major types of cancers, lung cancer is known to be the most chronic form of cancer in the world. The ...conventional management of lung cancer includes different medical interventions like chemotherapy, surgical removal, and radiation therapy. However, this type of approach lacks specificity and also harms the adjacent normal cells. Lately, nanotechnology has emerged as a promising intervention in the management and treatment of lung cancers. Nanotechnology has revolutionized the existing modalities and focuses primarily on reducing toxicity and improving the bioavailability of anticancer drugs to the target tumor cells. Nanocarrier systems are being currently used extensively to exploit and to overcome the obstructions induced by cancers in the lungs. The nano-carrier-loaded therapeutic drug delivery methods have shown promising potential in treating lung cancer as its target is to control the growth of tumor cells. In this review, various modes of nano drug delivery options like liposomes, dendrimers, quantum dots, carbon nanotubes and metallic nanoparticles have been discussed. Nano-carrier drug delivery systems emerge as a promising approach and thus is expected to provide newer and advanced avenues in cancer therapeutics.
•Lung cancer is one of the most prevalent form of cancer worldwide.•Traditional treatment methods includes surgery, radiation and chemotherapy.•Main side effects of existing treatments are nonspecific targeting and toxicity.•Novel drug delivery offers improved bioavailability and site-specific targeting.•Emerging trends in drug delivery will provide new direction to lung cancer clinics.
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