Statistical process control for high precision deep drawn sheet metal parts

In today\u27s world, industrial expertise has come to be judged in terms of the quality of the product. Good quality has become the ultimate aim in a manufacturing environment, which leads to many innovations for ease in the inspection of parts. In considering a metal working company like Hudson Tool & Die Company, a study of the various operations and the application of Statistical Process Control to the forming operations is performed using STORM software. Important characteristics have been carefully studied with regards to metal forming like uniform metal thickness, radius of the bend, depth of the drawing operation. In-depth analysis was performed on the pattern, and the cause of the variations. Various control charts such as average chart, range chart and p chart were obtained and different processes were studied. Computer aided quality control is fast becoming a standard in the manufacturing world. Non-contact gaging, coordinate measuring machines, and automatic conversion of the data into useful information are noteworthy and hence have been mentioned

Analysis and Survey of FPGA Based PROFIBUS Board

Fieldbus system has been established as a communication network, used to connect field devices such as sensors, transduser,controller,man machine interface.Currently a large number of global fieldbus standards are available for consumers.Citation of different types of field bus present an analytical review of various fieldbus systemthat how to gather the data from various equipment distributed far away from each other in the field with reduced wiring and cabling requirement, those are the basic components of communication system. This work also discuss about FPGA based PROFIBUS communication board. It proposes the alternative solution to complexity of communication system and devise it more reliable, high integral and transmission efficient

Astigmatism and vision:should all astigmatism always be corrected?

As technology and medical devices improve, there is much interest in when and how astigmatism should be corrected with refractive surgery. Astigmatism can be corrected by most forms of refractive surgery, such as using excimer lasers algorithms to ablate the cornea to compensate for the magnitude of refractive error in different meridians. Correction of astigmatism at the time of cataract surgery is well developed and can be achieved through incision placement, relaxing incisions and toric intraocular lens (IOL) implantation. This was less of an issue in the past when there was a lower expectation to be spectacle independent after cataract surgery, in which case the residual refractive error, including astigmatism, could be compensated for with spectacle lenses. The issue of whether presurgical astigmatism should be corrected can be considered separately depending on whether a patient has residual accommodation, and the type of refractive surgery under consideration. We have previously reported on the visual impact of full correction of astigmatism, rather than just correcting the mean spherical equivalent. Correction of astigmatism as low as 1.00 dioptres significantly improves objective and subjective measures of functional vision in prepresbyopes at distance and near

Effect of uncorrected astigmatism on vision

PURPOSE: To examine the effect of uncorrected astigmatism in older adults. SETTING: University Vision Clinic METHOD: Twenty-one healthy presbyopes, aged 58.9±2.8 years, had astigmatism of 0.0 to -4.0 x 90?DC and -3.0DC of cylinder at 90?, 180? and 45? induced with spectacle lenses, with the mean spherical equivalent compensated to plano, in random order. Visual acuity was assessed binocularly using a computerised test chart at 95%, 50% and 10% contrast. Near acuity and reading speed were measured using standardised reading texts. Light scatter was quantified with the cQuant and driving reaction times with a computer simulator. Finally visual clarity of a mobile phone and computer screen was subjectively rated. RESULTS: Distance visual acuity decreased with increasing uncorrected astigmatic power (F=174.50, p0.05), but the reliability and variability of measurements decreased with increasing uncorrected astigmatic power (p0.05), but subjective rating of clarity decreased with increasing uncorrected astigmatic power (p<0.001). Uncorrected astigmatism at 45? or 180? orientation resulted in a worse distance and near visual acuity, and subjective rated clarity than 90? orientation (p<0.05). CONCLUSION: Uncorrected astigmatism, even as low as 1.0DC, causes a significant burden on a patient’s vision. If left uncorrected, this could impact significantly on their independence, quality of life and wellbeing

Theranostic Applications of siRNA Bioconjugates in Cancer Detection and Treatment

Abstract The emerging field of RNA nanotechnology has led to rapid advances in the applications of RNA in chemical biology, medicinal chemistry, and biotechnology. At the forefront of its utility is the ability to self-assemble multiple siRNAs into nanostructure formulations capable of targeting selected oncogenes and potentiating the gene therapy of malignant tumors. Self-assembled siRNA integrates multiple siRNAs within a single molecular platform for silencing multiple oncogenic mRNA targets with high precision and efficacy to potentially induce cancer cell apoptosis through the RNA interference (RNAi) pathway. Furthermore, the conjugation of siRNA self-assemblies with bio-active probes results in multi-functional theranostic (therapy+diagnostic) agents capable of enhancing cancer cell detection and treatment. This includes the introduction of lipids for cell uptake, fluorophores for cell-based detection, and metallic nanoparticle formulations for optimizing siRNA biophysical and biological properties. The latter is a central focus of my thesis research objectives, aimed towards the development of self-assembled siRNA bioconjugates as effective anti-cancer agents. Glucose-regulated proteins (GRPs) are a class of chaperone proteins of the endoplasmic reticulum that serve as key sensors for misfolded proteins and trigger the unfolded protein response (UPR) under physiological and pathological stress conditions. Moreover, GRPs have been classified as clinically relevant biological markers in cancer detection and treatment and found to be over-expressed and cell surface localized in a wide range of cancer types. In cancer, the GRPs regulate cancer initiation, proliferation, adhesion, and invasion which contributes to metastatic spread and treatment resistance. Over the last decade, our research program has focused on the development of various high-order, self-assembled, multi-functional siRNAs capable of silencing the oncogenic GRPs, and reversing their protective UPR effects related to proliferative, pro-survival, and anti-apoptotic pathways in selected tumors. Chemical tools have been implemented to improve the poor pharmacological properties of siRNAs to maximize their full therapeutic efficacy against tumorigenic disease conditions, which are highlighted in Chapter 1 of this thesis. Chapter 2 highlights the development of synthetic strategies to improve siRNA metabolic stability, cellular uptake, and delivery, which are still in widespread demand for effective siRNA therapeutic applications. More specifically, this research aims to incorporate a small set of fatty acids into chemically derived siRNAs to improve their metabolic stability and cancer cell permeability. To achieve this goal, we have generated the higher-order siRNAs based on self-assembled branching structures. The self-assembled branch siRNAs were generated from their corresponding RNA template strands, which incorporated a synthetic ribouridine branchpoint synthon. This monomer was developed by an efficient solution-phase synthesis route and can be effectively incorporated within linear, V, and Y-shaped RNA templates by automated solid-phase RNA synthesis. Furthermore, an optimized coupling procedure has been developed for tagging variable saturated and unsaturated fatty acids onto linear, V- and Y-shape RNA templates. The RNA-fatty acid bioconjugates were analyzed, purified, and characterized by LC/MS. They were then hybridized with complementary RNA single strands to afford the amphiphilic self-assembled branch siRNA bioconjugates. The amphiphilic siRNA bioconjugates were detected by native PAGE, CD spectroscopy, and RP IP HPLC, while characterization of their self-assembled nanostructures was determined by DLS and TEM. Furthermore, the self-transfection capabilities of the siRNA-fatty acid bioconjugates and their biological activities within a model prostate cancer (PC-3) cell line revealed partial cell uptake, which contributed to modest RNAi activity when compared to the siRNA controls transfected with a commercially available transfection reagent. Nonetheless, this reported solid-phase RNA bioconjugation approach provides an important entry point for the incorporation of various hydrophobic and amphiphilic functional groups. This strategy may enable further development of new generation RNAi molecules for screening important oncogene targets and for improving cancer gene therapy applications. Chapter 3 describes the synthesis, characterization, and biological evaluation of a new class of bifunctional gold (Au)-RNA nanoparticles to improve cellular uptake and theranostic utility of the multi-functional siRNA nanostructures in prostate cancer cells. In this study, we have developed a simple, bottom-up approach using alkylamino modified RNAs to produce stable and small Au-RNA nanoparticle formulations bearing either a fluorescent reporter (fluorescein) or a fatty acid group (palmitamide) to track cell uptake in PC-3 prostate cancer cells. The resulting Au-functionalized RNA particles were found to be stable under reducing conditions according to UV-Vis spectroscopy. Sample characterization by DLS and TEM confirmed self-assembly into primarily small (~10-40 nm) spherical shaped nanoparticles anticipated to be applicable to cell biology. The application of Au-functionalized siRNA particles in prostate cancer (PC-3) cells resulted in the knockdown of GRP75, which led to detectable levels of cell death in the absence of a transfection vector. Consequently, this novel Au-RNA theranostic formulation may prove to be a valuable bifunctional probe in the early detection and treatment of prostate cancer and related solid tumors. Chapter 4 of this thesis summarizes our on-going and future work aimed at incorporating cell-targeting ligands within the Au-siRNA nanoparticle formulations for specific cancer treatment in cell cultures and within tumor-bearing mice models. The study aims to modify the Au-siRNA nanoparticle formulation with cell-targeting peptides (CTPs), which functions to target and bind to a cell surface receptor, in this case, PSMA, found on the surface of select prostate cancer cells. A PSMA-targeting peptide sequence has been selected for targeted delivery of the Au-siRNA formulation directly within PSMA+ prostate cancer cells for the application of cancer-targeting gene therapy. Taken together, this thesis will serve to highlight the synthetic strategies towards the development of higher-order self-assembled siRNA bioconjugates with self-transfection capabilities for silencing multiple oncogenic GRPs in cancer

Advances in cataract surgery

Cataract surgery is a technique described since recorded history, yet it has greatly evolved only in the latter half of the past century. The development of the intraocular lens and phacoemulsification as a technique for cataract removal could be considered as the two most significant strides that have been made in this surgical field. This review takes a comprehensive look at all aspects of cataract surgery, starting from patient selection through the process of consent, anaesthesia, biometry, lens power calculation, refractive targeting, phacoemulsification, choice of intraocular lens and management of complications, such as posterior capsular opacification, as well as future developments. As the most common ophthalmic surgery and with the expanding range of intraocular lens options, optometrists have an important and growing role in managing patients with cataract

Effect of meals with varying glycemic index on blood glucose response in type 2 diabetes mellitus

Background: In diabetes mellitus (DM) glucose is underused, producing hyperglycaemia. Dietary interventions would be effective in management of glycemic control in DM. The glycemic index (GI) and glycemic load (GL) takes into account the glycemic response. Foods with contrasting GI when incorporated into a meal are able to differentially modify glycemia. Currently there is no universal approach to the optimal dietary strategy for DM. Also, little is known about whether this is dependent on the size and composition of the meal. The purpose of the study was to evaluate the blood glucose response to mixed meals (with varying GI and GL) served to Type 2 DM subjects and to determine the relationship between GI, GL and Postprandial Plasma glucose levels (PPG) in Type 2 DM.Methods: This study included 30 Type 2 DM subjects and 30 Non Diabetic Subjects. The subjects were served Hospital based and Home based diet. The FPG (Fasting Plasma Glucose) and PPG values were analysed for comparing the effect of both the diets on plasma glucose levels.Results: After analysis of study data we found that plasma glucose response (FPG-126±6.1 mg/dl, PPG-144.3±4.5 mg/dl) for hospital based low GI meals is significantly lower (p <0.0001) than after one week follow up home based mixed GI meals, (FPG-135±4.5 mg/dl, PPG 158.3±4.5 mg/dl).Conclusions: It was concluded in the study that Plasma Glucose shows a positive response to high GI foods and this may aggravate the hyperglycemia already present in Type 2 DM. Low GI diets may be helpful in reducing risks related to Type 2 DM.

Comparison of surgical parameters using different lens fragmentation patterns in eyes undergoing laser-assisted cataract surgery

Purpose: To compare surgical parameters among eyes undergoing laser-assisted cataract surgery (LACS) using different lens fragmentation patterns (LFP). Methods: Prospective, randomized, unmasked clinical trial. One-hundred eyes underwent LACS and were randomly assigned to 1 of 3 LFP treatment groups: (1) laser capsulotomy only; no lens fragmentation (NLF) (n = 34); (2) three-plane chop (TPC) (n = 33); and, (3) pie-cut pattern (PCP) fragmentation (n = 33). Prechop phacoemulsification (PHACO) was performed on all eyes using the same femtosecond (FS) laser and active-fluidics PHACO machine. Main outcome measures: FS laser dock time (s), PHACO time (s), PHACO power (%), cumulative dissipated energy (CDE) (%-s), irrigating fluid volume, and operative time. Results: The 3 treatment groups were comparable in terms of patient age (P = 0.164) and nuclear density (P = 0.669). FS dock time was higher in the PCP group (184.18 ± 25.86) compared to the TPC (145.09 ± 14.15) group (P < 0.001). PHACO time was significantly shorter in the PCP (23.19 ± 17.20 s) compared to TPC (35.27 ± 17.70) and NLF (46.15 ± 23.72) groups (P < 0.001). PHACO power was lower in the PCP (11.81 ± 3.71) compared to the NLF (14.41 ± 1.88) and TPC (14.04 ± 2.46) groups (P < 0.001). CDE was lower in the PCP (2.85 ± 2.32) compared to NLF (6.55 ± 3.32) and TPC (6.55 ± 5.45) groups (P < 0.001). Fluid volumes and operative times were similar. Conclusion: LFP can influence PHACO surgical parameters. Extensive fragmentation patterns such as PCP appear to lower PHACO time, power, and CDE and may potentially reduce the risk of PHACO related complications

Initiation of Psychotropic Medication after Partner Bereavement: A Matched Cohort Study

Background Recent changes to diagnostic criteria for depression in DSM-5 remove the bereavement exclusion, allowing earlier diagnosis following bereavement. Evaluation of the potential effect of this change requires an understanding of existing psychotropic medication prescribing by non-specialists after bereavement. Aims To describe initiation of psychotropic medication in the first year after partner bereavement. Methods In a UK primary care database, we identified 21,122 individuals aged 60 and over with partner bereavement and no psychotropic drug use in the previous year. Prescribing (anxiolytic/hypnotic, antidepressant, antipsychotic) after bereavement was compared to age, sex and practice matched controls. Results The risks of receiving a new psychotropic prescription within two and twelve months of bereavement were 9.5% (95% CI 9.1 to 9.9%) and 17.9% (17.3 to 18.4%) respectively; an excess risk of initiation in the first year of 12.4% compared to non-bereaved controls. Anxiolytic/hypnotic and antidepressant initiation rates were highest in the first two months. In this period, the hazard ratio for initiation of anxiolytics/hypnotics was 16.7 (95% CI 14.7 to 18.9) and for antidepressants was 5.6 (4.7 to 6.7) compared to non-bereaved controls. 13.3% of those started on anxiolytics/hypnotics within two months continued to receive this drug class at one year. The marked variation in background family practice prescribing of anxiolytics/hypnotics was the strongest determinant of their initiation in the first two months after bereavement. Conclusion Almost one in five older people received a new psychotropic drug prescription in the year after bereavement. The early increase and trend in antidepressant use after bereavement suggests some clinicians did not adhere to the bereavement exclusion, with implications for its recent removal in DSM-5. Family practice variation in use of anxiolytics/hypnotics suggests uncertainty over their role in bereavement with the potential for inappropriate long term use

Assessment of dysphotopsia in pseudophakic subjects with multifocal intraocular lenses

Aim: To better understand the phenomenon of dysphotopsia in patients implanted with multifocal intraocular lenses (IOLs). Methods: Forty-five patients (aged 61.8±8.9 years) implanted bilaterally with Tecnis ZM900 (diffractive multifocal), Lentis Mplus MF30 (segmented refractive multifocal) or Softec-1 (monofocal) IOLs (each n=15) 4–6 months previously and who had achieved a good surgical outcome were examined. Each reported their dysphotopsia symptoms subjectively, identified its form (EyeVisPod illustrations), quantified retinal straylight (C-Quant) and halo perception (Aston halometer). Retinal straylight and halometry was repeated by a second masked clinician to determine interobserver repeatability. Results: Subjective dysphotopsia ratings were able to differentiate Tecnis ZM900 from Lentis Mplus MF30 (p0.10) quantification or between straylight and the halo area (p>0.30). Conclusions: Multifocal IOLs induce symptoms of dysphotopsia. Straylight did not differentiate between IOL designs, however halometry identified clear differences in light scatter due to the IOL optics. Whereas, subjective rating of overall dysphotopsia are not strongly associated with straylight or halo perception, the halometry polar diagram reflected the subjective descriptions of dysphotopsia