433 research outputs found
Direct replacement of antibodies with molecularly imprinted polymer (MIP) nanoparticles in ELISA - development of a novel assay for vancomycin
No full textA simple and straightforward technique for coating microplate wells with molecularly imprinted polymer nanoparticles (nanoMIPs) to develop ELISA type assays is presented here for the first time. NanoMIPs were synthesized by a solid phase approach with immobilized vancomycin (template) and characterized using Biacore 3000, dynamic light scattering and electron microscopy. Immobilization, blocking and washing conditions were optimized in microplate format. The detection of vancomycin was achieved in competitive binding experiments with a HRP-vancomycin conjugate. The assay was capable of measuring vancomycin in buffer and in blood plasma within the range 0.001-70 nM with a detection limit of 0.0025 nM (2.5 pM). The sensitivity of the assay was three orders of magnitude better than a previously described ELISA based on antibodies. In these experiments nanoMIPs have shown high affinity and minimal interference from blood plasma components. Immobilized nanoMIPs were stored for 1 month at room temperature without any detrimental effects to their binding properties. The high affinity of nanoMIPs and the lack of a requirement for cold chain logistics make them an attractive alternative to traditional antibodies used in ELIS
MIP Plasma Decapsulation of Copper-wired Semiconductor Devices for Failure Analysis
No full textThe majority of Integrated Circuit (IC) devices are encapsulated in wire-bonded plastic IC packages. Epoxy molding compound is used as the encapsulation material and gold was used as the bonding wire material. However, the increase of gold material price from 400 USD/ounce in year 2005 to 1400 USD/ounce in year 2013 results in a major cost issue in IC assembly and prompt industry to search for alternative bond wire materials. Due to its cost and performance advantages, copper wire bonding is steadily replacing traditional gold wire bonding in IC assembly. The share of copper wire bonding has increased from 1% in year 2007 to 10% in year 2010 and is expected to reach 30% in year 2013. In package level failure analysis, decapsulation is an important step to open the IC package to inspect the condition of internal components and locate possible failure sites for root cause analysis. Thus the requirement of a good decapsulation process is to selectively remove the epoxy molding compound encapsulation layer, while not damaging the semiconductor chip and metal bonding wires that locate inside the IC package. The mostly used conventional decapsulation technique is to use hot nitric or nitric and sulfuric mixture acid to etch away the molding compound, such process has been routinely used for gold wire bonded plastic IC package decapsulation. However, because copper wires are more susceptible to be corroded and damaged by the acid, the switching to copper wire bonding in IC industry has raised a problem for acid decapsulation. Copper bond wires suffer inevitable corrosion after acid decapsulation, thus further failure analysis on copper/aluminum bonding becomes difficult especially in the case of IC packages that went through thermal stressing conditions after quality tests. Conventional plasma decapsulation and laser-ablation also have inherent disadvantages, thus their application in copper-wired IC package decapsulation are limited. In this thesis, we introduce a solution to the copper-wired IC package decapsulation by using a Microwave Induced Plasma (MIP) system. The MIP system combines the high etching selectivity of a plasma with the speed and absence of RF fields of acid decapsulation. Characteristics of the MIP system are high power density, atmospheric pressure operation and absence of exposure of the samples to ions. As a result, fast, selective and safe decapsulation of copper wire bonded IC packages is achieved. The performance of this MIP system outperforms acid decapsulation in preservation of fine surface details on the copper wire bonds. Compared to conventional plasma etchers, the MIP system is at least 20 times faster and does not damage the functionality of the chip. The prototype setup of the MIP decapsulation system is described in Chapter 2. The core component in the MIP system is a Beenakker-type TM010 mode microwave resonant cavity, which is the plasma source that determines the plasma etching performance. Chapter 3 investigates problems when using the original Beenakker cavity as the source of the plasma. Modifications are proposed that enable generation of an atmospheric pressure high-power density stable Ar/O2/CF4 plasma. High power reflection in the MIP system is reduced by adding a variable antenna to the original coupling loop inside the cavity. Broad and stable plasma process window is achieved by adding another modification element that reduces the cavity’s quality factor. The power efficiency of the MIP system is estimated to be 80%, while the volume power density of MIP sustained by the modified Beenakker cavity is 1600 W/cm3 under 40 W input power. Based on the plasma chemistry, MIP afterglow etching recipes for a variety of materials are developed in Chapter 4. Ar/O2/CF4 plasma etching of epoxy molding compound, Si, SiO2, Si3N4, silicone, copper, aluminum, palladium, and gold are conducted. Those materials are of special interest because they are commonly used in semiconductor packages. The optimal recipes for high etching rates as well as the rate-limiting factors of etching each material are given. The results provide reference to plasma etching selectivity and preservation of certain materials during MIP decapsulation of IC packages. Chapter 5 focuses on the application of MIP afterglow etching in IC package decapsulation. Four different MIP decapsulation processes are proposed and their pros & cons are analyzed. These four processes covers all types of plastic IC package decapsulation tasks, including thermally stressed package decapsulation that cannot be handled by other techniques. After MIP afterglow decapsulation, Si3N4 passivation layer, Si die, Cu bond wires, Pd-coated Cu bond wires, Au bond wires, and Al bond pads inside the IC package can be cleanly exposed without any process-induced damage. Comparison of MIP decapsulation with the currently used alternative solution of cold acid decapsulation is made. The superior ability of preserving minute surface features by MIP decapsulation in a reasonable time that facilitates further failure-site analysis is demonstrated through case studies. The application of MIP afterglow etching in LED package decapsulation is explored in Chapter 6. High-power LED packages are cleanly decapsulated by MIP afterglow etching without influencing the functionality of the LED die. Different decapsulation processes for flip-chipped and gold wire-bonded LED packages are developed. Typical decapsulation duration for single LED package is 7 minutes for flip-chipped packages and 12 minutes for wire-bonded packages, which is at least 10 times shorter than conventional wet etching alternatives. The business development of the MIP system is described in Chapter 7. A review of the milestones in both scientific research and business development are given to show how both matter progressed together. Experiences and thoughts are shared which hopefully could be a reference for entrepreneurs in scientific world.Microelectronics & Computer EngineeringElectrical Engineering, Mathematics and Computer Scienc
Implementasi Early Alarm System Indicator sebagai Upaya Mengurangi Frekuensi Overload pada HD 785-7 di PT Putra Perkasa Abadi Site MIP Lahat
No full textIndustri pertambangan merupakan salah satu sektor yang memegang peranan penting dalam perekonomian Indonesia. Salah satu alat berat yang krusial dalam operasi tambang adalah hauler atau truk angkut, seperti unit HD 785-7. Overload pada hauler HD 785-7 terjadi ketika muatan yang diangkut melebihi kapasitas maksimal yang diizinkan oleh spesifikasi pabrikan. Kondisi ini tidak hanya mengurangi efisiensi bahan bakar, tetapi juga menimbulkan risiko signifikan terhadap integritas struktural dan mekanikal hauler. Penelitian ini bertujuan untuk mengurangi frekuensi overload pada unit hauler HD 785-7 di PT Putra Perkasa Abadi Site MIP Lahat melalui implementasi sistem Early Alarm Indicator. Overload pada hauler dapat menyebabkan kerusakan komponen seperti suspensi dan menurunkan kinerja operasional. Dengan sistem alarm dini ini, operator diharapkan lebih responsif terhadap kondisi overload, sehingga dapat meningkatkan efisiensi operasional dan menurunkan biaya perbaikan. Hasil penelitian menunjukkan penurunan frekuensi overload sebesar 21% dan peningkatan beban rata-rata yang terpantau menjadi 102,10 ton setelah implementasi sistem. Disarankan untuk menerapkan sistem Early Alarm Indicator pada semua unit hauler HD 785-7 di PT Putra Perkasa Abadi
Implementation of Pre-Cleaner as An Effort to Preventive Engine Lacks Power Bulldozer D85ess-2 Support Area Rom PT Putra Perkasa Abadi Site Mip Lahat
No full textBulldozer D85ESS-2 operating in the ROM Support Area of PT Putra Perkasa Abadi Site MIP Lahat often experiences engine lacks power problem, which disrupts productivity and increases maintenance costs. This problem is generally caused by air contamination entering the engine system, resulting in decreased combustion efficiency and component damage. This study aims to analyse the effectiveness of pre-cleaner implementation as a preventive measure in overcoming this problem. The method used was a quantitative approach with the collection and analysis of operational data from the D85ESS-2 bulldozer before and after the installation of the pre-cleaner. The data analysed included the frequency of occurrence of the engine lacks power problem, downtime duration, and fuel usage. The results showed that the implementation of a pre-cleaner on the D85ESS-2 bulldozer at PT Putra Perkasa Abadi successfully resolved the problem of engine lacks power by reducing the accumulation of coal dust in the air cleaner. The test results show significant improvements in engine performance, with most parameters meeting the set standards. Thus, the use of a pre-cleaner improves combustion efficiency, reduces maintenance costs, and extends engine life
Imprinted Oxide and MIP/Oxide Hybrid Nanomaterials for Chemical Sensors †
No full textThe oxides of transition, post-transition and rare-earth metals have a long history of robust and fast responsive recognition elements for electronic, optical, and gravimetric devices. A wide range of applications successfully utilized pristine or doped metal oxides and polymer-oxide hybrids as nanostructured recognition elements for the detection of biologically relevant molecules, harmful organic substances, and drugs as well as for the investigative process control applications. An overview of the selected recognition applications of molecularly imprinted sol-gel phases, metal oxides and hybrid nanomaterials composed of molecularly imprinted polymers (MIP) and metal oxides is presented herein. The formation and fabrication processes for imprinted sol-gel layers, metal oxides, MIP-coated oxide nanoparticles and other MIP/oxide nanohybrids are discussed along with their applications in monitoring bioorganic analytes and processes. The sensor characteristics such as dynamic detection range and limit of detection are compared as the performance criterion and the miniaturization and commercialization possibilities are critically discussed.© 2018 by the author
Variations of the femoral artery position in relation to femoral vein and mid-inguinal point: a cadaveric study
No full textIntroduction: Femoral artery is one of the major arteries in human body. It is more preference for catheterization in some medical procedures. This study was designed to identify anatomical variations of the femoral artery position, in relation to femoral vein and mid-inguinal point of human cadavers. Methods: Dissection was performed on 22 cadavers. The associations were analyzed using Fisher’s Exact test and correlation test. Results: There was superolateral positioning detected. Distal traversing was only observed on the left thigh. Bivariate analysis showed that there was a significant association of distance from anterior superior iliac spine (ASIS) to femoral artery between the right and left thigh. However, there was no significant association of distance from mid-inguinal point (MIP) to femoral artery between the right and left thigh, position of femoral artery to MIP between the right and left thigh and distance of traversing point between the right and left thigh. Conclusion: This study showed that distance from ASIS to mid-point of femoral artery was significantly associated with the left-right sided of cadavers, while distance from MIP to femoral artery, position of femoral artery to MIP and distance of traversing point were not significantly associated with the left-right sided of cadavers. These informations may help in diagnostic cardiac catheterization procedures and coronary interventions. Malaysian Journal of Medicine and Health Sciences (2023) 19(SUPP12): 1-6
Synthesis and Characterization of Hybrid Molecularly Imprinted Polymer (MIP) Membranes for Removal of Methylene Blue (MB)
No full textThis work reports the synthesis and characterization of a hybrid molecularly imprinted polymer (MIP) membrane for removal of methylene blue (MB) in an aqueous environment. MB-MIP powders were hybridized into a polymer membrane (cellulose acetate (CA) and polysulfone (PSf)) after it was ground and sieved (using 90 µm sieve). MB-MIP membranes were prepared using a phase inversion process. The MB-MIP membranes were characterized using Fourier Transform Infrared Spectroscopy (FTIR) and Scanning Electron Microscope (SEM). Parameters investigated for the removal of MB by using membrane MB-MIP include pH, effect of time, concentration of MB, and selectivity studies. Maximum sorption of MB by PSf-MB-MIP membranes and CA-MB-MIP membranes occurred at pH 10 and pH 12, respectively. The kinetic study showed that the sorption of MB by MB-MIP membranes (PSf-MB-MIP and CA-MB-MIP) followed a pseudo-second-order-model and the MB sorption isotherm can be described by a Freundlich isotherm model
Exploring the Multi-Objective Dial-A-Ride Problem: An Analysis of Genetic Algorithms and MIP
No full textThe Multi-Objective Dial-a-Ride Problem (DARP) poses significant challenges in the field of transportation optimization, requiring the simultaneous optimization of conflicting objectives such as travel costs, emission, and customer ride times. In this research, we analyse two distinct approaches for tackling the Multi-Objective DARP: Mixed-Integer Linear Programming (MIP) solvers and Genetic Algorithms (GAs). Through a series of experiments and performance evaluations on diverse problem instances, we assess the strengths and weaknesses of each method. We compare their efficiency, scalability, and ability to generate Pareto-optimal solutions. Additionally, the study explores the impact of algorithmic variations on the convergence and solution quality of the Genetic Algorithm. The results demonstrate that MIP solvers seem entirely unsuited for the generation of quality Multi-Objective Pareto fronts. Of the Genetic Algorithms, the algorithm extended with our proposed guiding heuristics in its genetic operators, manages to construct the best quality Pareto front, outperforming the other algorithms in both finding the best objective solution values, as well as pareto diversity and convergence. We discuss the practical implications of our findings, offering recommendations for researchers and practitioners in the realm of transportation optimization and emission reduction.Computer Science | Algorithmic
Lens ER-stress response during cataract development in Mip-mutant mice
No full textAbstractMajor intrinsic protein (MIP) is a functional water-channel (AQP0) that also plays a key role in establishing lens fiber cell architecture. Genetic variants of MIP have been associated with inherited and age-related forms of cataract; however, the underlying pathogenic mechanisms are unclear. Here we have used lens transcriptome profiling by microarray-hybridization and qPCR to identify pathogenic changes during cataract development in Mip-mutant (Lop/+) mice. In postnatal Lop/+ lenses (P7) 99 genes were up-regulated and 75 were down-regulated (>2-fold, p=<0.05) when compared with wild-type. A pathway analysis of up-regulated genes in the Lop/+ lens (P7) was consistent with endoplasmic reticulum (ER)-stress and activation of the unfolded protein response (UPR). The most up-regulated UPR genes (>4-fold) in the Lop/+ lens included Chac1>Ddit3>Atf3>Trib3>Xbp1 and the most down-regulated genes (>5-fold) included two anti-oxidant genes, Hspb1 and Hmox1. Lop/+ lenses were further characterized by abundant TUNEL-positive nuclei within central degenerating fiber cells, glutathione depletion, free-radical overproduction, and calpain hyper-activation. These data suggest that Lop/+ lenses undergo proteotoxic ER-stress induced cell-death resulting from prolonged activation of the Eif2ak3/Perk-Atf4-Ddit3-Chac1 branch of the UPR coupled with severe oxidative-stress
Induction of C-Mip by IL-17 Plays an Important Role in Adriamycin-Induced Podocyte Damage
No full textBackground/Aims: Although the disturbance of T lymphocyte and glomerular podocyte exerts a crucial function in the pathogenesis of proteinuria, the potential link is still unclear. Methods: The balance of Treg and Th17 cells, and the expression of IL-17/IL-17R and c-mip were investigated in adrimycin-induced nephropathy (AN) mice. The effect and mechanism of IL-17 on podocyte were explored in cultured podocytes. Results: The proportion of Th17 cells in peripheral blood mononuclear cells, the amount of IL-17 in serum and kidney cortical homogenates, and the expression of IL-17R and c-mip in glomerular podocyte were increased obviously in AN mice. In cultured podocytes, recombinant IL-17 led to an induction of apoptosis and cytoskeletal disorganization, an overproduction of c-mip while down-regulation of phosphor-nephrin, and an increased binding of c-mip to NF-κB/RelA. Silence of c-mip prevented podocyte apoptosis and reduction of phosphor-nephrin by prompting nuclear translocation of NF-κB/RelA in IL-17 treated cells. Persistent activation of NF-κB up-regulated pro-survival protein Bcl-2 and decreased podocyte apoptosis, but had no effect on phosphor-nephrin level. Conclusion: These findings demonstrated that induction of IL-17 released by Th17 cells plays a key role in podocytopathy most likely through down-regulation of phosphor-nephrin and Bcl-2 level via overproduction of c-mip
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