Theoretical study of thermoelectric cooling system performance

This work provides a theoretical investigation to study the effect of different operational parameters on theperformance of TE cooling system including the system COP and the rate of heat transfer. The parametersinvestigated are, the applied input power, inlet working fluid velocity, the arrangement of utilized TECs modules andfluid type. The geometry is created with ANSYS multi-physics software as a two-dimensional base case, it isconsisted from two attached horizontal ducts of length (520 mm) and (560 mm), the interface surface between the twoducts contains three thermoelectric modules (4 mm height by 40 mm wide and 40 mm length). The distance betweentwo consecutive thermoelectric modules (150 mm), the inlet and outlet duct diameter (15 mm) and the height of eachduct (10 cm), the inlet voltage to thermoelectric modules ranges from 8.0 V to 12 V and the water inlet velocity to thetwo ducts from 0.001 to 0.01 m/s. Theoretical results showed that the overall COP of TE cooling system is increasedwith the applied input power up to 8.0 W then it decreases with input power up to 18 W after that it takes nearly aconstant value, a noticeable enhancement in the COP is found when the three TECs are in use (Case 10) and the COPof TE cooling system using pure water and nanofluid with 0.05% of nanoparticles as coolants takes the maximumvalue

Long term visual outcomes in laser treated threshold retinopathy of prematurity in Central Saudi Arabia

AbstractPurposeTo assess the long term visual outcomes and refractive status of patients who underwent diode laser for threshold retinopathy of prematurity (ROP) and to investigate the risk factors leading to poor visual outcomes.MethodsFifty-seven patients (114 eyes) with threshold ROP who underwent laser therapy were contacted for reassessment. A chart review was performed for all patients to collect data on visual acuity, retinal status and strabismus. A favorable visual outcome was defined as ⩾20/160 (Snellen acuity) for young adults (cooperative patients), and ⩾CSM for children (uncooperative patients) while unfavorable visual outcome was defined as <20/160 or <CSM. Vision in uncooperative children was graded as central, steady, maintain. Descriptive and inferential analyses were conducted. Chi2 and odds ratios were calculated whenever appropriate. A P value <0.05 was considered as statistically significant.ResultsThe mean age at reassessment was 5.2±2.5years (range, 1–10years) where 36 (63.2%) patients were males and 21 (36.8%) were females. Out Of the 114 laser treated eyes, 73 (64%) were myopic, with mean spherical equivalent (SE) of −6.69 (5.9), range (−0.25 to −21) diaopters, 8 (7%) were emmetrope, while other 33 (29%) were hyperopic with mean SE of +2.43 (3.04), range (+0.25 to +17) diaopters. Strabismus was present in 31 patients (54.4%) of whom 81% (25/31) were esotropic. Retina was found to be normal in 77.1% of the examined eyes, while the remaining eyes had either macular dragging or retinal detachment. Almost 70% of the eyes with a normal retinal examination had favorable visual outcome. Thirteen (11.4%) eyes had zone 1 retinopathy, 83 (72.8%) eyes had zone 2 retinopathy and 2 (1.8%) eyes had zone 3 retinopathy. Vitreous hemorrhage was present in 7 (6.1%) eyes prior to laser treatment. The relationship between final retinal status and visual outcome was statistically significant (P<0.0001). There was no statistically significant correlation between visual outcome and the zone of the retinopathy (P=0.448).ConclusionThe majority of patients who underwent diode laser therapy for threshold ROP had favorable anatomical and visual outcomes. However, high refractive error and strabismus may be clinically the pertinent causes of visual impairment

Shared medical appointments may be effective for improving clinical and behavioral outcomes in type 2 diabetes: A narrative review

Type 2 diabetes mellitus (T2DM) is a complex chronic disease affecting over 400 million people worldwide. Managing T2DM and its associated complications in individual patient consultations poses substantial challenges to physicians due to limited time and resources and lack of access to multidisciplinary teams. Shared medical appointments (SMAs) are consecutive medical consultations provided by a physician in a group setting, where integrated medical care and patient education are delivered in a single session. SMAs allow physicians to deliver the same level of care to multiple patients at the same time, thereby maximizing available resources. However, the effectiveness and practicality of SMAs in the management of T2DM remains unknown. This narrative review summarizes current and emerging evidence regarding the effectiveness of SMAs in improving clinical outcomes in patients with T2DM, as well as whether SMAs are associated with reduced costs and improved diabetes-related behavioral and lifestyle changes. An extensive literature search was conducted on major electronic databases including PubMed and Google Scholar using keywords, including SMAs, group visits, and T2DM to identify all studies of SMAs in patients with T2DM. Studies in type 1 diabetes or mixed or unspecified populations were excluded, as well as studies where SMAs did not involve a physician since these do not meet the classical definition of a SMA. Nineteen studies were identified and are included in this review. Overall, current evidence suggests that SMAs delivered regularly over time may be effective in improving glycemic outcomes, diabetes knowledge, and some diabetes-related behaviors. However, the main limitation of existing studies was the paucity of comparisons with standard care which limits the ability to draw conclusions regarding whether SMAs are superior to standard care in T2DM management. Moreover, the small number of studies and substantial heterogeneity in study designs, populations, and interventions creates difficulties in establishing the practicality and efficiency of SMAs in the clinical care setting. We conclude that there remains a need for larger studies to identify populations who may or may not benefit from the SMA model of care and to clarify the potential benefits and barriers to implementing SMAs into routine diabetes care

Graphical Analysis and Revamping of Crude Distillation Units under Variable Operational Scenarios

Energy Cost Represents a Significant Part of the Total Operating Costs of Many Processing Units. Crude Distillation is an Energy Intensive Process. Energy Integration is a Typical Solution to Reduce Heating and Cooling Utilities through Maximizing the Target Temperature of Crude Oil Streams Before Entering the Furnace. over the Past Few Decades, Significant Progress Has Been Made in Energy Integration Methods Including Pinch Technology and Mathematical Programming Approaches. Very Recently, Graphical Techniques Have Been Developed for Revamping Studies and Energy Analysis. Such Diagrams Are Valuable in Energy Targeting to Identity Energy Inefficiencies and Are Key to Potential Modifications for Maximum Energy Integration. the Current Research Applies the Recent Graphical Revamping Methodology on an Existing Crude Atmospheric Distillation Unit. the Unit is Located in North of Egypt (Suez Region) and is Operated under Two Different Operational Modes; (1) Without Naphtha Stabilizer; the Process Reformer is in Operation to Reform All Naphtha Streams Without Stabilization and (2) with Naphtha Stabilizer; LPG is Separated from Naphtha Stream. a Graphical-Based Revamping Methodology is Applied to Retrofit the Existing Preheat Train. the Revamping Procedure Starts by Simulating the Existing HEN Data, Followed by Validation Against the Real Data. the Current Performance of the HEN is Analyzed using the Graphical Axes of Thot-Tcold Diagrams. the Graphical Method is Then Used to Identify Exchangers Across the Pinch and Recognize the Potential Modifications to Improve the Energy Performance and Reduce Fuel Consumption. Implementing the Graphical Identified Modifications on the Plant Resulted in the Following Benefits: (1) When Stabilizer is in Operation, Energy Savings Are Achieved by 21.1% with Additional Capital Investment of 0.81 MM$and Annual Energy Savings of 0.82 MM$, with a Payback Period of One Year. (2) When Reformer is in Operation, the Energy Savings Are 0.42 MM$with Capital Investment of 0.33 MM$. the Methodology Results Provide a Flexibility in Refineries Operations

Graphical Revamping Of A Crude Distillation Unit Under Two Variable Operational Scenarios - Naphtha Stabilizer And Reformer Operated

Energy costs represent significant parts of the total operating costs of crude refining industries. Energy integration is a typical solution to reduce heating and cooling utilities in crude refining plants through maximizing the target temperature of crude oil streams before entering the furnace. Over the past few decades, a significant progress has been made in energy integration methods including Pinch technology and mathematical programming approaches. Example of these is a graphical technique which plots Thot versus Tcold for energy analysis and revamping studies. The current research employs the Thot - Tcold diagrams in an algorithm to retrofit an existing crude atmospheric distillation unit (CDU) located in north of Egypt (Suez region). This real CDU unit is operated under two different operational modes: (i) without naphtha stabilizer; the process reformer is in operation to reform all naphtha streams without stabilization, and (ii) with naphtha stabilizer; LPG is separated from naphtha stream. The performance of the current HEN is analyzed using the graphical axes of Thot - Tcold diagrams. The graphical method is used to identify exchangers across the Pinch and recognize the potential modifications to improve the energy performance and reduce fuel consumption. Implementing the graphical identified modifications on the existing plant resulted in: (1) stabilizer scenario; energy savings are achieved by 21.1% with additional capital investment of 0.81 MM$and annual energy savings of 0.82 M$, (2) reformer scenario; the energy savings are 0.42 MM$with capital investment of 0.33 M$

Website Phishing Detection Using Machine Learning Techniques

Phishing is a cybercrime that is constantly increasing in the recent years due to the increased use of the Internet and its applications. It is one of the most common types of social engineering that aims to disclose or steel users sensitive or personal information. In this paper, two main objectives are considered. The first is to identify the best classifier that can detect phishing among twenty-four different classifiers that represent six learning strategies. The second objective aims to identify the best feature selection method for websites phishing datasets. Using two datasets that are related to Phishing with different characteristics and considering eight evaluation metrics, the results revealed the superiority of RandomForest, FilteredClassifier, and J-48 classifiers in detecting phishing websites. Also, InfoGainAttributeEval method showed the best performance among the four considered feature selection methods

Impacts of Dietary Lysine and Crude Protein on Performance, Hepatic and Renal Functions, Biochemical Parameters, and Histomorphology of Small Intestine, Liver, and Kidney in Broiler Chickens

The present study aimed to investigate the effects of increasing dietary lysine (Lys) levels with an adequate dietary crude protein (CP) content, as well as the effects of a reduction in dietary CP content with the recommended amino acid (AAs) level, on the performance, blood biochemical parameters, and histomorphology of the duodenum, liver, and kidney in broiler chickens. A total of 500 broiler chickens were randomly distributed into five dietary treatment groups, following a completely randomized design, where, at the beginning, the control group (C) was fed a diet containing the standard CP and Lys levels: 23% CP with 1.44% Lys during the starter period; 21.5% CP with 1.29% Lys during the growing period; and 19.5% CP with 1.16% Lys during the finishing period. The Lys content was increased by 10% above the recommended control basal requirements in the second group (Gr1) and by 20% in the third group (Gr2), while using the same recommended CP percentage as the C group. The fourth group (Gr3) had a 1% lower CP content and the fifth group had a 2% lower CP content than the C group, with the same recommended AA level as the C group. Increasing the Lys content in the Gr1 group improved the broilers’ weight gains (p \u3c 0.05) during the starter, growing, and finishing periods. Decreasing dietary CP with the standard AA levels (Gr3 and Gr4) did not significantly affect (p \u3e 0.05) the live weight gain, feed intake, or feed conversion ratio (FCR) of the broilers compared with those fed with the C diet. Blood total bilirubin, direct and indirect bilirubin, triglycerides, cholesterol, low-density lipoprotein (LDL), and very LDL were not different among the experimental groups. However, blood aspartate aminotransferase levels were increased (p \u3c 0.05) in the Gr1 and Gr3 groups compared with the other treatment groups. All dietary treatments decreased the serum creatinine levels (p \u3c 0.05) compared with the C group. The Gr2 broilers had greater serum total protein and globulin (p \u3c 0.05) than those receiving the other treatments. Increasing dietary Lys levels resulted in a significant improvement in duodenum villus height and width (p \u3c 0.05), while the low-CP diets resulted in shorter villi length and width, along with degenerated areas and lymphocytic infiltration. Low dietary CP content induced hepatocyte disorganization and moderate degeneration, along with vacuolated hepatic cells, excessive connective tissue, and lymphocytic infiltration. The cortical regions of the kidney exhibited obvious alterations in the Gr3 and Gr4 groups and large interstitial spaces were found between tubules. Renal tubules in the Gr3 and Gr4 groups were smaller in size and some of these tubules were atrophied. In conclusion, reducing dietary CP levels to 1% or 2% lower than the recommended level did not negatively affect growth performance, inducing minimal influence on the blood metabolic indicators of health status, and resulting in moderate alterations to the histomorphology of the duodenum, liver, and kidney. Furthermore, increasing the Lys content by 10% above the recommended level improved the growth performance, health status, and histomorphology of the duodenum, liver, and kidney in broiler chickens

Site-1 protease inhibits mitochondrial respiration by controlling the TGF-β target gene Mss51

The mitochondrial response to changes in cellular energy demand is necessary for cellular adaptation and organ function. Many genes are essential in orchestrating this response, including the transforming growth factor (TGF)-β1 target gene Mss51, an inhibitor of skeletal muscle mitochondrial respiration. Although Mss51 is implicated in the pathophysiology of obesity and musculoskeletal disease, how Mss51 is regulated is not entirely understood. Site-1 protease (S1P) is a key activator of several transcription factors required for cellular adaptation. However, the role of S1P in muscle is unknown. Here, we identify S1P as a negative regulator of muscle mass and mitochondrial respiration. S1P disruption in mouse skeletal muscle reduces Mss51 expression and increases muscle mass and mitochondrial respiration. The effects of S1P deficiency on mitochondrial activity are counteracted by overexpressing Mss51, suggesting that one way S1P inhibits respiration is by regulating Mss51. These discoveries expand our understanding of TGF-β signaling and S1P function

Carnosine supplementation improves serum resistin concentrations in overweight or obese otherwise healthy adults: A pilot randomized trial

Adipokines play an important role in the regulation of glucose metabolism. We have previously shown that carnosine supplementation in overweight or obese non-diabetic individuals improves glucose metabolism but does not change adiponectin concentrations. However, its effect on other adipokines has not been investigated. Herein we further determined the effect of carnosine supplementation on serum adipsin, resistin and leptin. Twenty-two overweight or obese otherwise healthy adults were randomly assigned to receive either 2 g of carnosine (n = 13) or identically looking placebo (n = 9) for 12 weeks. Serum adipsin, leptin and resistin were analyzed using a bead-based multiplex assay. Carnosine supplementation decreased serum resistin concentrations compared to placebo (mean change from baseline: -35 ± 83 carnosine vs. 35 ± 55 ng/mL placebo, p = 0.04). There was a trend for a reduction in serum leptin concentrations after carnosine supplementation (-76 ± 165 ng/mL carnosine vs. 20 ± 28 ng/mL placebo, p = 0.06). The changes in leptin and resistin concentrations were inversely related to the change in concentration for urinary carnosine (r = -0.72, p = 0.0002; r = -0.67, p = 0.0009, respectively), carnosine-propanal (r = -0.56, p = 0.005; r = -0.63, p = 0.001, respectively) and carnosine-propanol (r = -0.61, p = 0.002; r = -0.60, p = 0.002, respectively). There were no differences between groups in change in adipsin concentrations. Our findings show carnosine supplementation may normalize some, but not all, of the serum adipokine concentrations involved in glucose metabolism, in overweight and obese individuals. Further clinical trials with larger samples are needed to confirm these results