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While mechanical vapor compression is typically applied for the concentration of brine, new approaches that are less costly and less energy intensive are needed to facilitate minimal and zero liquid discharge. Several variations of reverse osmosis for high-salinity desalination and increasing recovery rates beyond the pressure limitation of conventional RO have been proposed in the literature. The promise of these enhanced RO approaches entails a reduction in energy consumption when compared with thermal desalination methods. In this paper, low-salt rejection reverse osmosis (LSRRO), cascading osmotically mediated reverse osmosis (COMRO), and osmotically assisted reverse osmosis (OARO) were comparatively assessed via module-scale, cost optimization models to gain an accurate perspective of the performance differences between each of these configurations. We quantified the optimal levelized cost of water (LCOW) of each technology for the case of desalinating feedwater at 70 g/L at 75% recovery, which would result in a brine concentration near 250 g/L, a level that allows further treatment with crystallizers. For baseline scenarios, LCOW results for LSRRO, COMRO, and OARO were 6.63, 7.90, and 5.14 $/m3 of product water, respectively, while the corresponding specific energy consumption (SEC) values were 28.9, 12.8, and 10.3 kWh/m3. A sensitivity analysis is also presented.

Freshwater scarcity is a dire problem for exposed human societies and natural ecosystems—a problem expected to grow worse with anticipated climate change. Reverse osmosis (RO) desalination is currently the most energy-efficient and ubiquitous desalination process used for freshwater production in water-scarce regions. The synergy of high solar radiation and significantly reduced costs in photovoltaics (PV) creates the opportunity for PV to become a dominant and sustainable solution for powering the energy-intensive process of desalination and reducing greenhouse gas emissions.While photovoltaic-powered reverse osmosis (PVRO) is a promising technological solution, several significant challenges must be further addressed to sustain high RO performance. First, the inherently intermittent nature of solar energy generation can adversely affect the freshwater conversion process and thereby decrease water recovery and quality. Furthermore, global desalination capacity is dominated by large-scale plants, whereas PVRO systems are currently limited to small-scale systems. Thus, to truly integrate renewable energy with desalination systems in an impactful way, there is a need to explore pathways for modifying the RO process to enable flexible operation on a large-scale, in response to power variability. Furthermore, the techno-economic feasibility of flexible, renewable-powered RO processes and the potential benefits that could be provided to variable renewable energy (VRE) plants and the electric grid warrants investigation. Brine minimization is another major challenge for sustainable desalination. Brine management is especially an issue for inland desalination plants. Novel approaches that are less costly and less energy intensive are needed to facilitate minimal and zero liquid discharge. To enable high-salinity desalination, several variations of osmotically assisted RO, which each surpass the pressure limitation of conventional RO, have been proposed in the literature but require further assessment. The promise of these enhanced RO approaches entails a reduction in energy consumption when compared with thermal desalination methods. The primary deliverables and novel contributions of this thesis include the development of (i) design, simulation, and cost optimization models for variable-powered, variable-salinity RO systems, (ii) module-scale, cost-optimization models for enhanced RO technologies that reduce transmembrane osmotic pressure to enable high-salinity desalination and brine minimization, (iii) examining the effects of cyclic reverse osmosis on inorganic scaling mitigation, and (iv) quantifying the availability of unconventional, alternative water sources to alleviate local water scarcity in the contiguous US. First, the techno-economic feasibility of PV-powered RO desalination plants in the Gulf region was assessed using Hybrid Optimization Model for Electric Renewables (HOMER) and Desalination Economic Evaluation Program (DEEP) to model both the power system and desalination system, respectively. Subsequently, an hourly simulation model for desalination was developed to replace the use of DEEP in the workflow. Grid-connected and off-grid cases with combinations of PV, batteries, and diesel generators were evaluated primarily by the levelized cost of electricity (LCOE) and levelized cost of water (LCOW). The shortcoming of conventional and PV-powered RO is that variable power compromises cumulative water production, which in turn increases water costs. Thus, we proposed the concept of active-salinity-control reverse osmosis (ASCRO) which enables control of the transmembrane osmotic pressure and water production in response to variable power. The ASCRO system dynamically controls energy consumption by operating across a range of feed salinity, allowing it to shift over a wide range of pump feed flows and pressures. To accomplish this, ASCRO utilizes feedwater from both low- and high-salinity sources. Enabling a dynamic power consumption profile can enhance demand-response capabilities, compensating for stressors on the grid. Moreover, ASCRO can improve the integration of renewable energy (RE) by responding to power fluctuations without compromising permeate production. This system can include on-site RE and energy storage to power the ASCRO plant and provide services to the grid. We considered the following grid-connected scenarios: 1) ASCRO, 2) ASCRO and battery storage, 3) ASCRO and photovoltaics (PV), and 4) ASCRO, battery storage, and PV. The LCOW was minimized by providing load-shifting and regulation capacity services in the California Independent System Operator (CAISO) market. We quantified that the ASCRO plant can ramp from minimum to maximum load within 84 seconds, which is adequate for participation in fast-timescale markets. The LCOW for these scenarios ranged from 49 – 59 cents/m³. We also present sensitivity analyses showing the effects of capital cost, CAISO market prices, and PV size on LCOW. To investigate alternative pathways to minimal and zero liquid discharge, low-salt rejection reverse osmosis (LSRRO), cascading osmotically mediated reverse osmosis (COMRO), and osmotically assisted reverse osmosis (OARO) were comparatively assessed via module-scale, cost optimization models to gain an accurate perspective of the performance differences between each of these configurations. We quantified the optimal LCOW of each technology for the case of desalinating feedwater at 70 g/L at 75% recovery, which would result in a brine concentration near 250 g/L, a level that allows further treatment with crystallizers. For baseline scenarios, LCOW results for OARO, COMRO, and LSRRO were 5.14, 7.90, and 6.63 $/m³ of product water, respectively, while the corresponding specific energy consumption (SEC) values were 10.31, 12.77, and 28.90 kWh/m³. A sensitivity analysis is also presented. Additionally, we sought to examine the possibility of whether adaptive RO operation could provide the added benefit of fouling mitigation. Using the Pitzer model, nucleation theory, and dissolution kinetics to guide a set of bench-scale fouling experiments, CaSO₄-NaCl solution, supersaturated with respect to gypsum, was fed through a membrane test cell to determine nucleation induction times, rates of flux decline, and scale reversal. Lastly, a geospatial analysis was conducted to estimate volumes of water deficits and potential alternative water sources for the contiguous US. Namely, wastewater effluent, brackish groundwater, agricultural drainage water, and produced water were considered in this analysis as alternatives for alleviating water scarcity. We formulated a conservative estimate of groundwater availability based on environmental flow limits. Additionally, agricultural drainage volumes were estimated based on USGS water use data. Overall, the results showed that water deficits amounted to an equivalent daily capacity of 149 million m³/day—nearly 50% more than the desalination capacity of the world in 2020. Furthermore, the total availability of alternative water sources was estimated to be between 192 – 240 million m³/day, but most of this volume was not in the same location as deficits. Thus, 58 – 65% of national water deficits would have to be alleviated via long-range transport. Additionally, the potential for integrating desalination and water reuse by interconnecting existing RO plants with wastewater treatments plants was also assessed.

Ferrimagnetic insulators capped with a heavy metal are becoming an increasingly interesting materials system in spintronics due to their unique ability for electrical manipulation and detection of magnetic states and spin textures via spin-orbit torques. The ability to engineer magnetic anisotropy is a powerful tool for tuning the recently discovered phenomena in these bilayers such as electrical switching or the stabilization of topological magnetic textures. We observe large shifts in the magnetic anisotropy in ${\mathrm{Tm}}_{3}{\mathrm{Fe}}_{5}{\mathrm{O}}_{12}$ and ${\mathrm{Y}}_{3}{\mathrm{Fe}}_{5}{\mathrm{O}}_{12}$ thin films due to heavy-metal capping layers, which strongly depends on the orientation of the substrate and therefore the orientation of the epitaxial films. This work suggests large Rashba spin-orbit coupling at the metal/ferrimagnetic-insulator interface, which can be engineered in spintronic devices that utilize spin-orbit torques for electrical control of the magnetization in magnetic insulators.

The study aims to measure the extent to which work pressure is mediated by the relationship between professional compatibility and work turnover, and to determine the impact of work pressure on the effectiveness and efficiency of workers, to indicate the role of work pressure in work turnover. The importance of the study comes from the role of work stress and its repercussions on the performance of workers in business organizations. It also highlights the relationship between professional alignment and work turnover. A questionnaire was designed and distributed on a simple random sample of (50) individuals, representing 65% of the study population, and recovered all of them. A number of statistical methods were used to validate the hypotheses, including Pearson correlation and simple regression analysis descriptive statistics (percentages, arithmetic averages, Standard deviations) to describe the characteristics of the study sample, Multiple regression analysis to test the effect of mediating work pressure (the intermediate variable) of the relationship between occupational compatibility (independent variable) and work rotation (dependent variable). A single variance analysis was also used to test differences in workers' perceptions of sources of work pressure attributable to personal variables. It also recommended the need to reduce the sources of work pressure related to the human resource by developing and diversifying training programs While providing requirements for a work environment that helps employees to carry out their duties in a highly efficient manner.

Interfacial magnetic anisotropy in magnetic insulators has been largely unexplored. Recently, interface-induced skyrmions and electrical control of magnetization have been discovered in insulator-based heterostructures, which demand a thorough understanding of interfacial interactions in these materials. We observe a substantial, tunable interfacial magnetic anisotropy between Tm_{3}Fe_{5}O_{12} epitaxial thin films and fifteen nonmagnetic materials spanning a significant portion of the periodic table, which we attribute to Rashba spin-orbit coupling. Our results show a clear distinction between nonmagnetic capping layers from the d block and the p block. This work offers a new path for controlling magnetic phases in magnetic insulators for low-loss spintronic applications.

Introduction Demographic change and demand for high quality of life lead to increasing implantation numbers. Aim of this study was to compare the Plasmafit® cup to Allofit® and Plasmacup®. Methods The study included 174 patients who had received 33 Plasmacup®, 68 Allofit® and 73 Plasmafit® cup implants. These were reviewed postoperatively, after 6 months control and after 12 months. Results No significant progressive migration could be discovered in any of the cup systems. At each follow-up the cups showed nearly constant values. Conclusions All examined acetabular cups showed excellent migration behavior within the first 12 postoperative months.

The interfacial Dzyaloshinskii-Moriya interaction (DMI) is responsible for the emergence of topological spin textures such as skyrmions in layered structures based on metallic and insulating ferromagnetic films. However, there is active debate on where the interfacial DMI resides in magnetic insulator systems. We investigate the topological Hall effect, which is an indication of spin textures, in Tm_{3}Fe_{5}O_{12} films capped with various metals. The results reveal that Pt, W, and Au induce strong interfacial DMI and topological Hall effect, while Ta and Ti cannot. This study also provides insights into the mechanism of electrical detection of spin textures in magnetic insulator heterostructures.

This study aimed to analyse historical food availability in Sudan during 1961-2013. This was achieved by assessing the food supply (kg/capita/yr.), dietary energy supply (DES) (kcal/capita/day), composition of diets and food self-sufficiency. The study depended on the available secondary data from FAO balance sheets. Percent share, annual cumulative growth rate and trends were used as analytical tools. The total food supply had a positive growth rate of 4.9%. The DES increased from 1743 to 2186 kcal/capita/day, implying that Sudan is food insecure. Cereals constitute approximately half of the total DES. The percentage share of vegetal sources was paramount in the DES (80%), protein supply (60%) and fat supply (45-68%) relative to that of animal sources. The per capita consumption of protein and fat (g/capita/day) were considered within the adequate supply, and below the average of the world and Arab countries. Carbohydrates ranked as the highest source contributing to the DES, followed by fats and proteins. These macro-nutrient contributions to the total DES fell within the recommendation ranges of the WHO for the balanced diets. The growth rate of imports outnumbered that of the domestic food supply and production, reflected in declining trend of the overall food self-sufficiency ratio by 1.5% per decade. The study recommended efficient use of Sudan abundant resources to increase food availability.

The purpose of this study was to check the concept of the cementless Metha® short hip stem in order to find out whether proximal physiological load transfer can be achieved. Fourty-three patients were included. Epidemiological factors were established. The Harris Hip Score was determined and measurement of bone mass density as well as osteodensitometric and radiological measurements was carried out pre-operatively, post-operatively, and after six, 12, 24, and 36 months. Harris Hip Score improved from 55.9 ± 12.4 pre-operatively to 94.8 ± 8.2 after 36 months (p

Objectives The study aimed to assess the relationship between coffee intake, obstructive sleep apnea risk (OSA), and glycemic control among patients with diabetes mellitus. Results There were 110 patients with diabetes and 96 healthy control subjects (matched for age and sex) attending a diabetes center زinTabuk, Saudi Arabia during the period from June 2018–October 2019. Stop-Bang questionnaire was used to assess OSA risk, and Epworth Sleepiness Scale to investigate daytime sleepiness. OSA risk and daytime sleepiness were higher among patients with diabetes compared to controls (4.34 ± 1.61 vs. 2.86 ± 1.24, and 8.31 ± 4.40 vs. 6.39 ± 3.70 respectively, P 0.05). Women with diabetes were younger with short duration since the diagnosis of diabetes and consumed less coffee compared to men, P

Robust hand gesture recognition is a critical ingredient of many human-computer interaction applications. Recently, Deep Neural Networks (DNNs) models have been widely applied to solve different computer vision problems. However, few researchers have applied DNNs to recognize static hand gestures. In this paper, an approach is proposed that leverages the recent progress on Convolutional Neural Networks (CNNs) and uses deep-learning-based strategy to recognize 24 hand gestures from the American Sign Language (ASL). This approach is built on recently released small CNNs architectures to leverage their high accuracy rate, maintaining small model size and the feasibility to deploy on resource constrained-devices. Here, the architectures of SqueezeNet and MobileNets for both RGB and depth images are utilized, and a late-fusion strategy to concatenate features from both RGB and depth modalities is performed. Also, an effective encoding of depth images as rendered RGB images is proposed to handle depth data with CNNs, and thus improve recognition performance. Experiments are executed on a challenging publicly available American Sign Language – Finger Spelling (ASL-FS) dataset acquired by an RGB-D camera to evaluate the proposed architecture. Results show that the proposed approach achieves higher average accuracy, outperforming all previous methods, and has great feasibility to apply the models on resource-constrained devices and embedded visual applications.

Cementless straight stems show very good survival rates. However, the more distal force application of straight stems may lead to release-related proximal stress-shielding. Nevertheless, this technical brief had the objective of conducting a biomechanical in vitro analysis comparing short stems with established straight stems with respect to their primary torsional stability. Two cementless short hip stems and three cementless straight hip stems were implanted in n = 5 synthetic femora each. Torsional torques were applied into the hip stems at a continuous interval of ±7 Nm. Micromotions were measured by six inductive extensometers on four different measurement levels. At the proximal measuring point, significantly smaller relative micromotions of the CLS® prosthesis could be detected compared to all other stem models (p

Aseptic loosening is the main reason for revision of total hip arthroplasty, and relative micromotions between cementless acetabular cups and bone play an important role regarding their comparatively high loosening rate. Therefore, the aim of the present study was to analyze the influence of resulting frictional torques on the primary stability of press-fit acetabular cups subjected to two different bearing partners. A cementless press-fit cup was implanted in bone-like foam. Primary stability of the cup was analyzed by determining spatial total, translational, and rotational interface micromotions by means of an eddy current sensor measuring system. Torque transmission into the cup was realized by three synchronous servomotors considering resultant friction torques based on constant friction for ceramic-on-ceramic (CoC: μ = 0.044; max. resultant torque: 1.5 Nm) and for ceramic-on-polyethylene (CoP: μ = 0.063; max. resultant torque: 1.9 Nm) bearing partners. Rotational micromotion of CoC was 8.99 ± 0.85 µm and of CoP 13.39 ± 1.43 µm. Translational micromotion of CoC was 29.93 ± 1.44 μm and of CoP 39.91 ± 2.25 μm. Maximum total relative micromotions were 37.10 ± 1.07 μm for CoC and 51.64 ± 2.18 μm for CoP. Micromotions resulting from CoC were statistically lower than those resulting from CoP (p

Background The resultant hip force causes a varus torque which must be compensated by a shear force couple depending on the stem alignment of the prosthesis. Since the prosthesis is substantially less flexible than the bone, the interior of the femur is stiffened over the entire prosthesis length. The present study thus aims at analyzing short-stem prostheses for its elastic bending characteristics, considering inappropriate valgus alignment of the prosthetic stem. Methods Five short stem prostheses were implanted each in synthetic femora in a standardized manner – in neutral and valgus stem alignments. Bending movements were recorded applying a tilting torque MX of ±3.5 Nm in medio-lateral direction. Variance analyses and Friedman tests were used. A P-value Findings Bending movements b1-b6 showed significant differences (P Interpretation Regarding the elastic bending behavior we see a relevant influence of the stems´ design. We conclude that the short-stem principle does not necessarily require the shortest possible prosthesis but rather a long and thin extending stem tip to optimize the lever ratios, ensuring a more physiological bending behavior of the femur. In addition, without sufficient anchoring of the prosthesis, the valgus stem alignment could favor tilting of the implant and should therefore be avoided.

Mit der steigenden Anzahl von Endoprothesentragern wird die Revision von Huftendoprothesen weiter zunehmen. Die Rekonstruktion ossarer Defekte mit allogenen Knochen ermoglicht die Wiederherstellung eines knochernen Lagers und verbessert die langfristige Verankerung und die Resultate. Eine ausreichende Primarstabilitat des gewahlten Konstrukts ist Voraussetzung fur ein gutes klinisches Ergebnis und die langfristige ossare Integration, ebenso wie ein guter Kontakt des implantierten Knochens zum Knochenlager. Die Knochentransplantation kann zu einem „Down-Grading“ eines knochernen azetabularen Defekts beitragen und die Verwendung eines groseren Stutzimplantats vermeiden. Auch bei der Rekonstruktion femoraler Defekte kann die Knochentransplantation das Knochenlager verbessern und die Implantation eines kleineren Schafts ermoglichen, allerdings sind der Indikationsstellung bei sehr ausgepragten Defektzonen Grenzen gesetzt. Aufgrund der guten langfristigen Ergebnisse der modularen Revisionsschafte hat sich das „Impaction-Bone-Grafting“ im Bereich des Schaftes nicht generell etabliert.

The quality of the tunnel barrier at the ferromagnet/graphene interface plays a pivotal role in graphene spin valves by circumventing the impedance mismatch problem, decreasing interfacial spin dephasing mechanisms and decreasing spin absorption back into the ferromagnet. It is thus crucial to integrate superior tunnel barriers to enhance spin transport and spin accumulation in graphene. Here, we employ a novel tunnel barrier, strontium oxide (SrO), onto graphene to realize high quality spin transport as evidenced by room-temperature spin relaxation times exceeding a nanosecond in graphene on silicon dioxide substrates. Furthermore, the smooth and pinhole-free SrO tunnel barrier grown by molecular beam epitaxy (MBE), which can withstand large charge injection current densities, allows us to experimentally realize large spin accumulation in graphene at room temperature. This work puts graphene on the path to achieve efficient manipulation of nanomagnet magnetization using spin currents in graphene for logic and memory applications.