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Background: The ACTION IO study (NCT03584191) aimed to identify perceptions, attitudes, behaviors, and potential barriers to effective obesity care across people with obesity (PwO) and healthcare professionals (HCPs). Results from Saudi Arabia are presented here. Methods: A survey was conducted from June to September 2018. In Saudi Arabia, eligible PwO were ≥18 years with a self reported body mass index of ≥30 kg/m2. Eligible HCPs were in direct patient care. Results: The survey was completed by 1,000 PwO and 200 HCPs in Saudi Arabia. Many PwO (68%) and HCPs (62%) agreed that obesity is a chronic disease. PwO felt responsible for their weight management (67%), but 71% of HCPs acknowledged their responsibility to contribute. Overall, 58% of PwO had discussed weight with their HCP in the past 5 years, 46% had received a diagnosis of obesity, and 44% had a follow up appointment scheduled. Although 50% of PwO said they were motivated to lose weight, only 39% of HCPs thought their patients were motivated to lose weight. Less than half of PwO (39%) and HCPs (49%) regarded genetic factors as a barrier to weight loss. Many PwO had seriously attempted weight loss (92%) and achieved ≥5% weight loss (61%), but few maintained their weight loss for >1 year (5%). Conclusion: Saudi Arabian results have revealed misperceptions among PwO and HCPs about obesity, highlighting opportunities for further education and training about obesity including the biologic basis and clinical management.

Several properties make titanium and its alloy the primary candidate to attain weight and functional advantages because of its promising properties such as high strength to weight ratio, high corrosion resistivity, and high yield stress. Although titanium alloys have superior properties, some inherent characteristics such as high chemical reactivity and low thermal conductivity lead to poor machinability and result in premature tool failure and shortened tool life. In order to overcome the heat dissipation challenge during machining of titanium alloys, nano-cutting fluids are utilized as they offer higher observed thermal conductivity values compared to the base oil. Thus, in the current work, multi-walled-carbon nanotubes (MWCNTs) cutting fluids along with minimum quantity lubrication (MQL) have been employed during machining Ti-6Al-4V. On the other hand, developing a multiobjective optimization model for machining titanium alloys is a promising step in order to minimize machining cost, achieve excellent surface quality, and increase the cutting tool life by selecting the optimal cutting conditions (i.e. cutting speed, feed rate, depth of cut). In this study, response surface methodology (RSM), and genetic algorithm (GA) are employed to model and optimize three main machining responses: tool wear, surface quality, and power consumption. Three main independent processes parameters are considered when machining titanium alloys, namely; cutting speed, feed rate, and percentage of added nano-additives.

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The cooling applications during machining has significant effects on the production costs, surface quality, and the mechanical properties of the final product. In conventional flood cooling, a large amount of continuous cooling fluid is usually used, and that increases the cost of the product as well as the harmful effects on the environment and the machining operator. This study focuses on simulating alternative cooling system, called minimum quantity coolant (MQC), which used an optimal flow rate compared to classical flood cooling. The cooling fluid is directly provided to the cutting edge through the insert holder. In the current work, a computational fluid dynamic (CFD) model has been developed to study the effects of the cooling fluid velocity on the accessibility of coolant to the chip-tool interface area under using various types of cooling fluids. Three types of coolant are used (i.e. water, mineral oil, and nano-fluid). The results of the proposed CFD model have been classified into two phases. The first phase obtains the coolant accessibility percentage into the chip-tool interface (MA%) with different coolant velocities (i.e., 0.5, 1, 1.5, and 2 m/s) for the three studied coolants. The second phase discusses the heat transfer effectiveness for the employed coolants with different inlet velocities since it is an important aspect, especially when machining hard-to-cut materials. It was found that increasing the coolant velocity would increase the coolant accessibility percentage into the chip-tool interface area. However, no significant effect has been found after 1.5 m/s for all employed coolants.