132 research outputs found
Dynamic response of a laterally-loaded infinite rigid cylinder embedded in a saturated poroelastic medium
In this paper, an analytical solution for the response of a rigid cylinder embedded in a full-space poroelastic medium subjected to a dynamic lateral load is derived. The problem is idealised as a two-dimensional problem. The solution is obtained using Biotâs theory for acoustic waves. In this solution, the displacements of the solid skeleton and the pore pressure are expressed in terms of three scalar potentials. These potential correspond to the wave velocities of the slow and fast compressional wave and to the shear wave. The governing equation for the dynamic motion is expressed in the frequency domain using Fourier transformation and the potentials are shown to be given by Holmholtz equations
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The effect of RAN inhibition on human colorectal cancer cells (CRC)
Colorectal cancer (CRC) is the third most widespread and fourth most fatal
malignancy disease. The CRC from a primary site can spread to other tissues,
forming secondary tumours. CRC can metastasise to the liver through the effect
of K-Ras and Pten mutation (Mt.) (Abbas et al. 2020). This study aimed to assess
the hypothesis that the Ran inhibitor mebendazole MBZ reduces cell invasion
and metastasis of CRC. I have investigated MBZ effect on the CRC isogenic
human cell lines with specific mutations (HCT-116 K-Ras, DLD-1 K-Ras and Pten
deletion and wild type HCT-116 and DKO-3. I used qRT-PCR and western
blotting to identify expression levels of various genes and signalling molecules
after treatment with 0.5 mM MBZ. In addition, several assays were performed to
investigate MBZ effect on biological properties of the cells such as proliferation,
migration, invasion, and colony formation. MBZ downregulated Ran and induced
apoptosis through inhibition of Bcl-2 expression as well as inducing caspase -3,
-7, -9 and PARP cleavage. Moreover, MBZ showed an effect on immune
response by down regulating C5a, IL-1à and IL-1α analysed at mRNA level.
When treated with MBZ, the migration, invasion and colony formation abilities of
HCT-116 K-Ras Mt., DLD-1 K-Ras Mt. and HCT-116 Pten-/- were significantly
reduced compared to a control treated cell line. This was also the case with wild type cell lines such as HCT-116 and DKO-3. Furthermore, signalling molecules
such as p- Erk 1/2 and p- Akt were upregulated after MBZ treatment and exert
inhibition on Akt 1/2/3 and VEGFR1/2 mRNA levels. In conclusion; MBZ which is
a Ran inhibitor, has significantly reduced proliferation, colony formation, and
migration in colorectal cell lines with K-Ras and Pten gene deletion compared to
wild type cells in a dose-dependent manner. This work paves the way to clinical
validation of MBZ as a combination therapy for reducing the invasion of CRC
cells
Changes in pulmonary function in patients with ulcerative colitis
SummaryObjectivesInformation on the occurrence and frequency of pulmonary involvement in patients with ulcerative colitis (UC) is inconsistent. Some authors reported pulmonary impairment with UC by standard pulmonary function tests (PFTs) and documented a reduced diffusing capacity for carbon monoxide (DLCO) especially in patients with active disease, whereas others could not detect differences in routine PFTs between UC patients and controls.AimThe aim of this prospective study was to determine the frequency and type of pulmonary dysfunction in patients with UC with respect to disease activity. Furthermore, to evaluate the influence of smoking, nutritional status, sputum cytology and sulphasalazine therapy on PFT parameters.Patients and methodsTwenty-six patients with UC (20 with active disease, 6 inactive) and 16 age and sex matched healthy controls were investigated with respect to the following pulmonary function tests, forced vital capacity (FVC), forced expiratory volume in the 1s (FEV1%) and their ratio (FEV1/FVC) and forced expiratory flow 25â75% (FEF25â75%) as well as oxygen saturation. For UC patients, colonoscopy and biopsy were done. Disease activity was assessed by Truelove index for UC. Induced sputum was sampled for cytology. Smoking habit, body mass index (BMI) and medications were recorded.ResultsFifteen out of 26 patients with UC (57.6%) exhibited at least one pathological pulmonary function test (<80% of predicted value). Small airway obstruction was reported in the 15 patients, restrictive dysfunction in 30.7% and obstructive dysfunction in 11.5%. The impairment of PFTs was significant and more pronounced in patients with active disease, FVC (â14% of predicted), FEV1 (â9% of predicted) and FEF25â75% (â32% of predicted), P<0.01, 0.05 and 0.01, respectively. There was no significant influence of smoking and medications on PFTs.ConclusionsUC patients show significantly decreased lung function tests in comparison to healthy controls. The impairment in active disease exceeded that during the remission. Early recognition is important, as they can be strikingly steroid responsive
Effect of Trichoderma reesei degraded date pits on antioxidant enzyme activities and biochemical responses of broiler chickens
The long-term use of antimicrobials as growth promoters in poultry feed leads to antimicrobial resistance in pathogens. Thus, alternatives to antibiotics are essential for reasons associated with both safety and cost-effectiveness. Underutilized plant sources need to be developed to replace antibiotics in broiler feed. Several feed resources have been introduced so far, but they have yet to be applied widely. Date pits are a major by-product of the date industry (6â8%) and have the potential antioxidant to replace antibiotics. In this study, fresh date pits were degraded using the mold Trichoderma reesei under solid-state degradation (SSD), resulting in degraded date pits (DDP). A total of 180 Brazilian âCobb 500â broiler chicks were divided into six feed treatments in triplicate groups. The treatments were corn-soy basal diet (positive control; C+), corn-soy + 20% oxytetracycline at 0.05% (negative control; Câ), corn-soy + 10% DDP, corn-soy + 0.2% mannan-oligosaccharides (MOS), corn-soy + 0.1% mannose, and corn-soy + 0.2% mannose. The antioxidant and biochemical effects of DDP, MOS, and mannose were determined in the blood serum, liver, and intestine of broilers at age 21 and 42 days. The results indicated that the contents of antioxidants such as flavonoids and phenolics, as well as the MOS content in DDP, were increased by the degradation process. Additionally, mannose, glucose, arabinose, rhamnose, and glucuronic acid were significantly increased in DDP after degradation. The activity of antioxidant enzymes (GPxâglutathione peroxidase, catalase, and SODâsuperoxide dismutase) in the serum, liver, and intestine of broilers fed with diets containing 10% DDP and 0.2% MOS was increased significantly compared to the control group. Malondialdehyde activity was decreased, whereas the mean corpuscular hemoglobin level and the iron content were significantly upregulated in the broilers fed with 10% DDP, 0.1% mannose, and 0.2% MOS diets compared with the control. Thus, DDP can be used to improve the antioxidant status and has a prebiotic-like effect in broiler chicken performance
Intestinal development and histomorphometry of broiler chickens fed Trichoderma reesei degraded date seed diets
A study was conducted to investigate the impact of degraded date pits (DDP) on the development and morphology of the intestine in broilers. Trichoderma reesei was used to produce the DDP using a solid-state degradation method. One hundred and eighty broilers were divided into six treatments in triplicate groups of 10 chicks each. The dietary treatments were: positive control with corn-soy basal diet, negative control with corn-soy basal diet + 20% oxytetracycline at 0.05%, corn-soy basal diet + 10% DDP, corn-soy basal diet + 0.2% mannan-oligosaccharides (MOS), corn-soy basal diet + 0.2% mannose and corn-soy basal diet + 0.1% mannose for 6 weeks. The results indicate that a 10% DDP diet increased the activities of the pancreatic enzymes, the villus length, and the villus/crypt ratio, and decreased the crypt depth of the intestine. In conclusion, when compared to oxytetracycline and MOS, DDP can be used as a replacement for antibiotic growth promoters for broilers while improving gut development and intestinal health
EVALUATION OF WHEAT FLOUR BLENDED WITH DIFFERENT RATIOS OF MORINGA OLEIFERA LEAVES AND SEEDS
Chemical composition, minerals content, amino acids, fiber fractions, fatty acids profile, total phenols, total flavonoids and antioxidant activity were determined in wheat flour (WF) 72%, moringa leaves powder (MLP), defatted moringa seeds powder (DMSP) and moringa seeds (MS). Pasting profile and rheological properties of blends supplemented with MLP at levels of 3, 6, 9 and 12% or DMSP at levels of 5, 10, 15 and 20% were also studied. The highest moisture and carbohydrate contents were found in WF (12.60 and 85.05%), respectively. MLP had higher ash and fiber contents (8.87 and 7.91%), respectively, while, protein and fat contents were higher in DMSP and in MS. Mineral content (Ca, K, Mg, P, Na and Fe) in MLP was the highest, while DMSP was higher in Zn content than that of other samples. Fiber fractions of WF were lower than that of both MLP and DMSP. Total essential amino acids of DMSP was higher (19.25%) than that of MLP and WF (12.45 and 4.16%), respectively. Oleic acid was the predominant fatty acid (66.85%) in moringa seeds oil. MLP had the highest value of total phenolic, total flavonoid and antioxidant activity (11.97, 8.02 and 15.87 mg/g), respectively. Color measurements showed that all of MLP, DMSP and WF blends decreased in L*, a*,however, they increased in b*, saturation, hue and âE values.   Supplementation with MLP and DMSP at all levels decreased the peak viscosity, trough, breakdown, final and setback viscosities. While, it increased water absorption, dough development time, mixing tolerance index and dough weakening. On contrary, arrival time and dough stability were decreased. Also, MLP and DMSP decreased the extensibility, resistance to extension, maximum resistance to extension energy of dough and the proportional number
Thermal performance enhancement of a flat plate solar collector using hybrid nanofluid
Covalent Functionalized-Multi wall carbon nanotubes (CF-MWCNTs) and Covalent Functionalized-graphene nanoplatelets (CF-GNPs) with hexagonal boron nitride (h-BN) were suspended in distilled water to prepare the hybrid nanofluids as working fluids inside the Flat Plate Solar Collector (FPSC). Different concentrations of the hybrid nanoparticles were considered and Tween-80 (Tw-80) was used as a surfactant. The stability and thermophysical properties were tested using different measurement tools. The structural and morphological properties were examined using FTIR, XRD, UVâvis spectrometry, HRTEM, FESEM, and EDX. The thermal efficiency of FPSC were tested under different volumetric flow rates (2 L/min, 3 L/min, and 4 L/min), whereas the efficiency of the collector was determined based on ASHRAE standard 93-2010. As a result, the most thermal-efficient solar collector improved up to 85% with hybrid nanofluid as the absorption medium at 4 L/min flow rate. Increment in nanoparticlesâ concentrations enhanced thermal energy gain and resulted in higher fluid outlet temperature
Vibration induced memory effects and switching in ac-driven molecular nanojunctions
We investigate bistability and memory effects in a molecular junction weakly
coupled to metallic leads with the latter being subject to an adiabatic
periodic change of the bias voltage. The system is described by a simple
Anderson-Holstein model and its dynamics is calculated via a master equation
approach. The controlled electrical switching between the many-body states of
the system is achieved due to polaron shift and Franck-Condon blockade in the
presence of strong electron-vibron interaction. Particular emphasis is given to
the role played by the excited vibronic states in the bistability and
hysteretic switching dynamics as a function of the voltage sweeping rates. In
general, both the occupation probabilities of the vibronic states and the
associated vibron energy show hysteretic behaviour for driving frequencies in a
range set by the minimum and maximum lifetimes of the system. The consequences
on the transport properties for various driving frequencies and in the limit of
DC-bias are also investigated.Comment: 15 pages, 20 figures, published versio
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