Graphene/zinc oxide nanocomposite was synthesised via a facile, green and efficient approach consisted of novel liquid phase exfoliation and solvothermal growth for sensing application. Highly pristine graphene was synthesised through mild sonication treatment of graphite in a mixture of ethanol and water at an optimum ratio. The X-ray diffractometry (XRD) affirmed the hydrothermal growth of pure zinc oxide nanoparticles from zinc nitrate hexahydrate precursor. The as-prepared graphene/zinc oxide (G/ZnO) nanocomposite was characterised comprehensively to evaluate its morphology, crystallinity, composition and purity. All results clearly indicate that zinc oxide particles were homogenously distributed on graphene sheets, without any severe aggregation. The electrochemical performance of graphene/zinc oxide nanocomposite-modified screen-printed carbon electrode (SPCE) was evaluated using cyclic voltammetry (CV) and amperometry analysis. The resulting electrode exhibited excellent electrocatalytic activity towards the reduction of hydrogen peroxide (H2O2) in a linear range of 1-15 mM with a correlation coefficient of 0.9977. The sensitivity of the graphene/zinc oxide nanocomposite-modified hydrogen peroxide sensor was 3.2580 μAmM(-1) with a limit of detection of 7.4357 μM. An electrochemical DNA sensor platform was then fabricated for the detection of Avian Influenza H5 gene based on graphene/zinc oxide nanocomposite. The results obtained from amperometry study indicate that the graphene/zinc oxide nanocomposite-enhanced electrochemical DNA biosensor is significantly more sensitive (P
Breast cancer is the abnormal, uncontrollable proliferation of cells in the breast. Conventional treatment modalities like chemotherapy induce deteriorating side effects on healthy cells. Non-viral inorganic nanoparticles (NPs) confer exclusive characteristics, such as, stability, controllable shape and size, facile surface modification, and unique magnetic and optical properties which make them attractive drug carriers. Among them, carbonate apatite (CA) particles are pH-responsive in nature, enabling rapid intracellular drug release, but are typically heterogeneous with the tendency to self-aggregate. Here, we modified the nano-carrier by partially substituting Ca2+ with Mg2+ and Fe3+ into a basic lattice structure of CA, forming Fe/Mg-carbonate apatite (Fe/Mg-CA) NPs with the ability to mitigate self-aggregation, form unique protein corona in the presence of serum and efficiently deliver doxorubicin (DOX), an anti-cancer drug into breast cancer cells. Two formulations of Fe/Mg-CA NPs were generated by adding different concentrations of Fe3+ and Mg2+ along with a fixed amount of Ca2+ in bicarbonate buffered DMEM (Dulbecco's Modified Eagle's Medium), followed by 30 min incubation at 37 °C. Particles were characterized by turbidity analysis, z-average diameter and zeta potential measurement, optical microscopy, field emission scanning electron microscopy (FESEM), Fourier transform infrared spectroscopy (FTIR), energy dispersive X-ray (EDX), flame atomic absorption spectroscopy (FAAS), pH dissolution, drug binding, cellular uptake, thiazolyl blue tetrazolium bromide (MTT) assay, stability analysis, and protein corona study by LCMS (Liquid chromatography-mass spectrometry). Both formulations of Fe/Mg-CA displayed mostly uniform nano-sized particles with less tendency to aggregate. The EDX and FAAS elemental analysis confirmed the weight (%) of Ca, Fe and Mg, along with their Ca/P ratio in the particles. A constant drug binding efficiency was noticed with 5 μM to 10 μM of initial DOX concentration. A pH dissolution study of Fe/Mg-CA NPs revealed the quick release of DOX in acidic pH. Enhancement of cytotoxicity for the chemotherapy drug was greater for Fe/Mg-CA NPs as compared to CA NPs, which could be explained by an increase in cellular internalization as a result of the small z-average diameter of the former. The protein corona study by LCMS demonstrated that Fe/Mg-CA NPs exhibited the highest affinity towards transport proteins without binding with opsonins. Biodistribution study was performed to study the effect of DOX-loaded Fe/Mg-CA NPs on the tissue distribution of DOX in Balb/c 4T1 tumor-bearing mice. Both formulations of Fe/Mg-CA NPs have significantly increased the accumulation of DOX in tumors. Interestingly, high Fe/Mg-CA NPs exhibited less off-target distribution compared to low Fe/Mg-CA NPs. Furthermore, the blood plasma analysis revealed prolonged blood circulation half-life of DOX-loaded low and high Fe/Mg-CA NPs compared to free DOX solution. Modifying CA NPs with Fe3+ and Mg2+, thereby, led to the generation of nano-sized particles with less tendency to aggregate, enhancing the drug binding efficiency, cellular uptake, and cytotoxicity without hampering drug release in acidic pH, while improving the circulation half-life and tumor accumulation of DOX. Therefore, Fe/Mg-CA which predominantly forms a transport protein-related protein corona could be a proficient carrier for therapeutic delivery in breast cancer.
Computer-aided diagnosis for the reliable and fast detection of coronavirus disease (COVID-19) has become a necessity to prevent the spread of the virus during the pandemic to ease the burden on the healthcare system. Chest X-ray (CXR) imaging has several advantages over other imaging and detection techniques. Numerous works have been reported on COVID-19 detection from a smaller set of original X-ray images. However, the effect of image enhancement and lung segmentation of a large dataset in COVID-19 detection was not reported in the literature. We have compiled a large X-ray dataset (COVQU) consisting of 18,479 CXR images with 8851 normal, 6012 non-COVID lung infections, and 3616 COVID-19 CXR images and their corresponding ground truth lung masks. To the best of our knowledge, this is the largest public COVID positive database and the lung masks. Five different image enhancement techniques: histogram equalization (HE), contrast limited adaptive histogram equalization (CLAHE), image complement, gamma correction, and balance contrast enhancement technique (BCET) were used to investigate the effect of image enhancement techniques on COVID-19 detection. A novel U-Net model was proposed and compared with the standard U-Net model for lung segmentation. Six different pre-trained Convolutional Neural Networks (CNNs) (ResNet18, ResNet50, ResNet101, InceptionV3, DenseNet201, and ChexNet) and a shallow CNN model were investigated on the plain and segmented lung CXR images. The novel U-Net model showed an accuracy, Intersection over Union (IoU), and Dice coefficient of 98.63%, 94.3%, and 96.94%, respectively for lung segmentation. The gamma correction-based enhancement technique outperforms other techniques in detecting COVID-19 from the plain and the segmented lung CXR images. Classification performance from plain CXR images is slightly better than the segmented lung CXR images; however, the reliability of network performance is significantly improved for the segmented lung images, which was observed using the visualization technique. The accuracy, precision, sensitivity, F1-score, and specificity were 95.11%, 94.55%, 94.56%, 94.53%, and 95.59% respectively for the segmented lung images. The proposed approach with very reliable and comparable performance will boost the fast and robust COVID-19 detection using chest X-ray images.
Penekanan saraf lateral kutaneus femoral merupakan punca kepada penyakit meralgia parestetika. Gejala penyakit ini ialah kesakitan dan perubahan sensori pada bahagian lateral paha. Namun, gejala penyakit ini seakan menyerupai gejala penyakit lain seperti radikulopati lumbar, penyempitan ruang femoro-acetabular, bursitis trokanterik dan beberapa contoh lain. Meralgia parestetika merupakan diagnosis secara pengecualian setelah penyebab kepada kesakitan pada bahagian lateral paha tidak dapat dibuktikan melalui hasil penyiasatan yang terperinci. Pengetahuan anatomi tentang saraf yang mensarafi bahagian paha adalah amat penting untuk mengenalpasti punca kesakitan yang dialami. Kami ingin melaporkan satu kes yang melibatkan seorang pesakit lelaki berumur 46 tahun, telah didiagnos menghidap kencing manis, darah tinggi, masalah jantung yang telah datang ke Jabatan Kecemasan dan Trauma dengan aduan kesakitan akut pada bahagian lateral paha kanan. Kesakitan yang dialami digambarkan sebagai rasa seperti terbakar, dicucuk dan disertai dengan rasa kebas. Selain itu, terdapat pengurangan sensasi rasa pada bahagian paha yang sakit. Tiada aduan berkaitan sakit pada rangsangan ringan (allodinia) atau sakit yang berlebihan pada rangsangan kuat (hiperalgesia). Bacaan gula darah kapilari ialah 8.4 mmol/l dan keputusan HbA1c ialah 7%. Diagnosis meralgia parestetika telah disahkan setelah semua kemungkinan diagnosis lain tidak dapat dibuktikan melalui pemeriksaan fizikal, ujian makmal dan radiologi (x-ray, ultrasound dan MRI). Keadaan pesakit bertambah baik selepas diberikan rawatan ubat secara oral dan menjalani sesi fisioterapi.
Observations and modeling studies have shown that during CO2 injection into underground carbonate reservoirs, the dissolution of CO2 into formation water forms acidic brine, leading to fluid-rock interactions that can significantly impact the hydraulic properties of the host formation. However, the impacts of these interactions on the pore structure and macroscopic flow properties of host rock are poorly characterized both for the near-wellbore region and deeper into the reservoir. Little attention has been given to the influence of pressure drop from the near-wellbore region to reservoir body on disturbing the ionic equilibrium in the CO2-saturated brine and consequent mineral precipitation. In this paper, we present the results of a novel experimental procedure designed to address these issues in carbonate reservoirs. We injected CO2-saturated brine into a composite core made of two matching grainstone carbonate core plugs with a tight disk placed between them to create a pressure profile of around 250 psi resembling that prevailing in reservoirs during CO2 injection. We investigated the impacts of fluid-rock interactions at pore and continuum scale using medical X-ray CT, nuclear magnetic resonance, and scanning electron microscopy. We found that strong calcite dissolution occurs near to the injection point, which leads to an increase in primary intergranular porosity and permeability of the near injection region, and ultimately to wormhole formation. The strong heterogeneous dissolution of calcite grains leads to the formation of intra-granular micro-pores. At later stages of the dissolution, the internal regions of ooids become accessible to the carbonated brine, leading to the formation of moldic porosity. At distances far from the injection point, we observed minimal or no change in pore structure, pore roughness, pore populations, and rock hydraulic properties. The pressure drop of 250 psi slightly disturbed the chemical equilibrium of the system, which led to minor precipitation of sub-micron sized calcite crystals but due to the large pore throats of the rock, these deposits had no measurable impact on rock permeability. The trial illustrates that the new procedure is valuable for investigating fluid-rock interactions by reproducing the geochemical consequences of relatively steep pore pressure gradients during CO2 injection.
Eight caaes of this condition are described, the patients being four Ceylonese, three Indians, and one Chinese, all males except one. Symptoms consisted of breathlessness and cough, sputum being sometimes purulent and occasionally blood-stained. Six of the patients complained of loss of weight, and in one, a Ceylonese schoolboy, this was the only presenting symptom. The authors found the most troublesome complaint to be a paroxysmal cough which was always worst at night. On clinical examination rhonchi were heard scattered throughout both lung fields in five cases, the lungs being clear in the other three. X-ray examination showed characteristic mottling of both lungs in four cases and of one lung in one case; another showed increased vascular markings, while in two the lungs were clear. Sputum was examined for tubercle bacilli and mites but none were found. The technique used for searching for mites is not described. A marked eosinophilia was found in all cases, the highest count recorded being 33, 264 eosinophils per cmm.Treatment consisted of arsenic, given in the form of neoarsphenamine, six injections of 0.3 gm. in six cases, and stovarsol 4 grains t.d.s. for seven and ten days respectively in the other two. Four of the patients were cured, three were improved, while one was showing a favourable response although treatment had not been completed.The author emphasizes the importance of performing repeated blood counts in order to avoid missing this condition. Out of the eight cases which he describes, one had been wrongly diagnosed as pulmonary tuberculosis and three as bronchial asthma. One of the latter had an initial eosinophil count of 4, 092 which rose to 17, 700 three weeks later. H. T. H. Wilson
Chest radiography, or chest X-ray (CXR), is not only an important tool for triaging and screening for pulmonary tuberculosis (TB) but is also useful in aiding diagnosis when pulmonary TB cannot be confirmed bacteriologically. Sabah is a state with high TB burden with the incidence rate of 124/100,000 population in 2015. Access to chest radiography is limited in many settings in Sabah. In 2016, the TB and Leprosy Control Unit of Sabah State Health Department started systematic screening for TB with the help of a mobile digital X-ray unit.
Anticorrosive properties of nano silicate from paddy husk in salt medium was investigated via weight loss method, Tafel
polarization and impedance techniques. Prior to the corrosion test, the silica powder was obtained from burning the
rice husk and extended with a chemical treatment process. The size of silica powder was characterized via zeta sizer and
showed the amount of micro silica particle appear more than the nano size particle. Nano silica powder was produced
from the refluxing process of micro silica to enhance the good properties of silica particle. The corrosion inhibition
efficiency of nano silicate showed good inhibition with increased in inhibitor concentrations. Weight loss test exhibits
high inhibition as more than 80% even, immersed in the corrosive medium until 14 days. The nano silicate inhibitor
affected the anodic reaction as showed by Tafel plot analysis. Impedance results also correlated with other test as shown
by the large size of Nyquist semicircle which represents as high resistance of charge transfer. The surface morphology
of inhibited specimen showed a smooth surface after nano silicate inhibitor applied in the NaCl medium as observed
through scanning electron microscopy (SEM) and energy-dispersive x-ray spectroscopy (EDX).
The values of beam quality correction factor kQ that were experimentally determined from year 2002 to 2008 were analysed. As kQ is the function of ionization chamber and beam quality, the analysis were based on three cases namely (a) kQ(NE2571, 6 MV x-rays) that were determined from 17 measurements in the duration of 69 months at 6 radiotherapy centres, (b) kQ(NE2571, 10 MV x-rays) from 7 measurements in the duration of 12 months at one radiotherapy centre, and (c) kQ(NE2581, 6 MV x-rays) from 5 measurements in the duration of 5 months also at one radiotherapy centre. The purpose is to examine, in each case, the variation kQ for all the measurements. In other words, to see variation kQ with time. Results obtained are 0.993(NE2571, 6 MV), 0.986(NE2571, 10 MV) and 0.986(NE2581, 6 MV). This shows that in each case, despite the difference in the experimental data in getting kQ for all measurement, kQ remains constant with time. Reasons for this are explained.
The microencapsulation of three model drugs; metronidazole, paracetamol and sulphapyridine into Poly (dl-Lactide-Co-Glycolide) (PLGA) scaffolds were probed using X-ray Powder Diffraction (XRPD). Changes in the diffraction patterns of the PLGA scaffolds after encapsulation was suggestive of a chemical interaction between the pure drugs and the scaffolds and not a physical intermixture.
BACKGROUND: Traumatic pneumopericardium is rare and usually results from blunt injury. Diagnosis through clinical and chest X-ray is often difficult. Ultrasound findings of A-line artifacts in the cardiac window may suggest pneumopericardium.
CASE PRESENTATION: A young man involved in a car accident and sustained blunt thoracic injuries, among others. As part of primary survey, FAST scan was performed. Subxiphoid view to look for evidence of pericardial effusion showed part of the cardiac image obscured by A-lines. Other cardiac windows showed only A-lines, as well. A suspicion of pneumopericardium was raised and CT scan confirmed the diagnosis.
CONCLUSIONS: Although FAST scan was originally used to look for presence of free fluid, with the knowledge of lung ultrasound for pneumothorax, our findings suggest that FAST scan can also be used to detect pneumopericardium.
Perovskite-structured lead titanate thin films have been grown on FTO-coated glass substrates from a single-source heterometallic molecular complex, [PbTi(μ2-O2CCF3)4(THF)3(μ3-O)]2 (1), which was isolated in quantitative yield from the reaction of tetraacetatolead(IV), tetrabutoxytitanium(IV), and trifluoroacetic acid from a tetrahydrofuran solution. Complex 1 has been characterized by physicochemical methods such as melting point, microanalysis, FTIR, (1)H and (19)F NMR, thermal analysis, and single-crystal X-ray diffraction (XRD) analysis. Thin films of lead titanate having spherical particles of various sizes have been grown from 1 by aerosol-assisted chemical vapor deposition at 550 °C. The thin films have been characterized by powder XRD, scanning electron microscopy, and energy-dispersive X-ray analysis. An optical band gap of 3.69 eV has been estimated by UV-visible spectrophotometry.
Chemical composition of fine (PM2.5) aerosol samples collected for the 5 years period (2001- 2005) using Gent Stacked filter unit sampler at Klang Valley (3 o 10 ’ 30 ’’ N, 101 o 43 ’ 24 ’’ E) were analysed using Neutron Activation Analysis (NAA) and Proton Induced X-ray Emission (PIXE). Results of the study show that the major component of the fine aerosol was black carbon and sulfur with the mass concentration ranged from 4.4 - 6.7µg m -3 and 1.2 - 1.9µg m -3 , respectively. The total fine aerosol mass concentration were in the ranged of 25 - 31µg m -3 with the reconstructed mass was about 50% as relative to the gravimetric mass. Statistical method, factor analysis with varimax approach has been applied to the aerosol composition data for the fingerprint identification. The analysis produces five identified fingerprint represent soil, industry, motor vehicles/biomass burning and Pb and Zn sources. There is also an unidentified source that could be related to unknown industrial activities.
This present study was conducted to produce defatted oil palm shell (OPS) nanoparticles. Wherein, the OPS nanoparticles
were defatted by solvent extraction method. Several analytical methods including transmission electron microscope (TEM),
X-ray diffraction (XRD), particle size analyzer, scanning electron microscope (SEM), SEM energy dispersive X-ray (SEM-EDX)
and thermal gravimetric analyzer (TGA) were used to characterize the untreated and defatted OPS nanoparticles. It was
found that 75.3% OPS particles were converted into nanoparticles during ball milling. The obtained OPS nanoparticles had
smaller surface area with angular, irregular and crushed shapes under SEM view. The defatted OPS nanoparticles did not
show any agglomeration during TEM observation. However, the untreated OPS nanoparticles had higher decomposition
temperature as compared to the defatted OPS nanoparticles. Based on the characterization results of the OPS nanoparticles,
it is evident that the defatted OPS nanoparticles has the potentiality to be used as filler in biocomposites
Tin selenide (SnSe) and copper indium diselenide (CuInSe2) compounds were synthesized by high temperature reaction method using combination of sealed ampoule (at relatively low pressure ~10-1 Pa without inert gas) and heating at specific temperature profile in rocking furnace. Powder X-Ray diffraction analysis showed that the products involved only single phases of SnSe and of CuInSe2 only. Using the reaction products as source materials, the SnSe and CuInSe2 thin films were vacuum-deposited on glass substrates at room temperature. Structural, elemental, surface morphological and optical properties of the as-deposited films were studied by X-Ray diffraction (XRD), energy dispersive X-Ray (EDX) analysis, field emission scanning electron microscopy (FESEM) and UV-Vis-NIR spectroscopy. Single phase of SnSe and CuInSe2 films were obtained by thermal evaporation technique from synthesized SnSe and CuInSe2 compound without further treatment.
The most widely used method for detecting Coronavirus Disease 2019 (COVID-19) is real-time polymerase chain reaction. However, this method has several drawbacks, including high cost, lengthy turnaround time for results, and the potential for false-negative results due to limited sensitivity. To address these issues, additional technologies such as computed tomography (CT) or X-rays have been employed for diagnosing the disease. Chest X-rays are more commonly used than CT scans due to the widespread availability of X-ray machines, lower ionizing radiation, and lower cost of equipment. COVID-19 presents certain radiological biomarkers that can be observed through chest X-rays, making it necessary for radiologists to manually search for these biomarkers. However, this process is time-consuming and prone to errors. Therefore, there is a critical need to develop an automated system for evaluating chest X-rays. Deep learning techniques can be employed to expedite this process. In this study, a deep learning-based method called Custom Convolutional Neural Network (Custom-CNN) is proposed for identifying COVID-19 infection in chest X-rays. The Custom-CNN model consists of eight weighted layers and utilizes strategies like dropout and batch normalization to enhance performance and reduce overfitting. The proposed approach achieved a classification accuracy of 98.19% and aims to accurately classify COVID-19, normal, and pneumonia samples.
Ni3A1 is an intermetallic compound which has unique property with temperature. Annealing is done at temperature 300, 500, and 700°C for 1 hour and analyzed with X-ray Diffraction (XRD) and Energy Dispersive X-ray (EDX) analysis for their crystallographic nature. EDX confirmed the composition of Ni3A1 with exact stoichiometry, whereas the XRD confirmed the crystallographic nature of the material. The mechanical properties by hardness results showed that Ni3A1 has highest Vickers hardness value of 554 HV when it is non-heat treated. Its hardness drops as it undergoes annealing process. Corrosion analysis by tafel test shows that its polarization resistance may increase up to 4145 W cm2 when annealed at high temperature. These results show that Ni3A1 is a promising material to be considered as an alternative automotive body.
Geopolymer concrete has the potential to replace ordinary Portland cement which can reduce carbon dioxide emission to the environment. The addition of different amounts of steel fibers, as well as different types of end-shape fibers, could alter the performance of geopolymer concrete. The source of aluminosilicate (fly ash) used in the production of geopolymer concrete may lead to a different result. This study focuses on the comparison between Malaysian fly ash geopolymer concrete with the addition of hooked steel fibers and geopolymer concrete with the addition of straight-end steel fibers to the physical and mechanical properties. Malaysian fly ash was first characterized by X-ray fluorescence (XRF) to identify the chemical composition. The sample of steel fiber reinforced geopolymer concrete was produced by mixing fly ash, alkali activators, aggregates, and specific amounts of hook or straight steel fibers. The steel fibers addition for both types of fibers are 0%, 0.5%, 1.0%, 1.5%, and 2.0% by volume percentage. The samples were cured at room temperature. The physical properties (slump, density, and water absorption) of reinforced geopolymer concrete were studied. Meanwhile, a mechanical performance which is compressive, as well as the flexural strength was studied. The results show that the pattern in physical properties of geopolymer concrete for both types of fibers addition is almost similar where the slump is decreased with density and water absorption is increased with the increasing amount of fibers addition. However, the addition of hook steel fiber to the geopolymer concrete produced a lower slump than the addition of straight steel fibers. Meanwhile, the addition of hook steel fiber to the geopolymer concrete shows a higher density and water absorption compared to the sample with the addition of straight steel fibers. However, the difference is not significant. Besides, samples with the addition of hook steel fibers give better performance for compressive and flexural strength compared to the samples with the addition of straight steel fibers where the highest is at 1.0% of fibers addition.
This present study investigated the effect of Captisol, a chemically modified cyclodextrin, on the in vitro dissolution of glimepiride. We prepared glimepiride-Captisol complexes of different mass ratios (1:1, 1:2, and 1:3 w/w) by a physical mixing or freeze-drying technique, and found that complexation with Captisol enhanced the water solubility of glimepiride. Molecular docking and dynamic simulation predicted complex formation; at the same time, Fourier transform infrared spectroscopy, differential scanning calorimetry, powder X-ray diffractometry, and scanning electron microscope indicated molecular interactions that support complexation. We also found that an inclusion complex was better than a physical mixture in enhancing the complexation of glimepiride with Captisol and enhancing water solubility. Phase solubility study of the glimepiride-Captisol complex showed an AL-type profile, implying the formation of a 1:1 inclusion complex. The study also revealed that pH influenced the stability of the complex because the stability constant of the glimepiride-Captisol complex was higher in distilled water of pH ∼6.0 than in phosphate buffer of pH 7.2.
In primary care, chest X-rays are commonly performed to assess patients presenting with a prolonged
cough. However, the extent to which the flms are accurately interpreted depends on the skill of the
doctors. Doctors with insufcient experience may miss an exact diagnosis when evaluating a flm,
especially in patients with nonspecifc symptoms, such as in the case discussed in this paper.
( Copied from article ).