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Due to polymeric wear debris causing osteolysis from polymer, metal ions causing metallosis from metal, and brittle characteristic causing fracture failure from ceramic in the application on bearing of total hip prosthesis requires the availability of new material options as a solution to these problems. Polycrystalline diamond (PCD) has the potential to become the selected material for hard-on-hard bearing in view of its advantages in terms of mechanical properties and biocompatibility. The present study contributes to confirming the potential of PCD to replace metals and ceramics for hard-on-hard bearing through von Mises stress investigations. A computational simulation using a 2D axisymmetric finite element model of hard-on-hard bearing under gait loading has been performed. The percentage of maximum von Mises stress to respective yield strength from PCD-on-PCD is the lowest at 2.47%, with CoCrMo (cobalt chromium molybdenum)-on-CoCrMo at 10.79%, and Al 2 O 3 (aluminium oxide)-on-Al 2 O 3 at 13.49%. This confirms that the use of PCD as a hard-on-hard bearing material is the safest option compared to the investigated metal and ceramic hard-on-hard bearings from the mechanical perspective.

In designing porous scaffolds, permeability is essential to consider as a function of cell migration and bone tissue regeneration. Good permeability has been achieved by mimicking the complexity of natural cancellous bone. In this study, a porous scaffold was developed according to the morphological indices of cancellous bone (porosity, specific surface area, thickness, and tortuosity). The computational fluid dynamics method analyzes the fluid flow through the scaffold. The permeability values of natural cancellous bone and three types of scaffolds (cubic, octahedron pillar, and Schoen's gyroid) were compared. The results showed that the permeability of the Negative Schwarz Primitive (NSP) scaffold model was similar to that of natural cancellous bone, which was in the range of 2.0 × 10 -11 m 2 to 4.0 × 10 -10 m 2 . In addition, it was observed that the tortuosity parameter significantly affected the scaffold's permeability and shear stress values. The tortuosity value of the NSP scaffold was in the range of 1.5-2.8. Therefore, tortuosity can be manipulated by changing the curvature of the surface scaffold radius to obtain a superior bone tissue engineering construction supporting cell migration and tissue regeneration. This parameter should be considered when making new scaffolds, such as our NSP. Such efforts will produce a scaffold architecturally and functionally close to the natural cancellous bone, as demonstrated in this study.

Yield fluctuation is a major risk in all agricultural sectors, and it influences Goal 2 (food security) of the UN SDGs. Yield fluctuations are expected due to climate change, risking stable coffee supplies, and compromising coffee-exporting countries' ability to earn revenue to pay for food imports. Technology minimizing yield fluctuations is crucial for food security and for coffee farmers to earn a stable income. Fluctuations are small if yields remain close to the mean yield trends. In this study, the coffee yields of major producers are analyzed, together with zonal temperature data, to see where coffee is grown with stable technology under rising temperatures; thus, we demonstrate the advantages of the Yield Stability Index (YSI) over traditional stability measurements in guiding policy formulation and managerial decisions. The Yield Stability Index (YSI) is applied for 1961-1994 and 1995-2020, for the world's 12 major coffee-producing countries. The YSI indicates that of the 12 countries, only Indonesia, Honduras, and Mexico maintain stable yield levels, while Brazil and Vietnam considerably improve their yield stability, which traditional stability measures cannot grasp. Country-wise differences exist in environmental vulnerability and adaptability, with implications for food security. The novelty is the application of the YSI, and the connection between yield stability, climate change, and food security.

Due to various concerns about the use of metal-on-metal that is detrimental to users, the use of metal as acetabular cup material was later changed to ultra high molecular weight polyethylene (UHMWPE). However, the wear on UHMWPE releases polyethylene wear particles, which can trigger a negative body response and contribute to osteolysis. For reducing the wear of polyethylene, one of the efforts is to investigate the selection of metal materials. Cobalt chromium molybdenum (CoCrMo), stainless steel 316L (SS 316L), and titanium alloy (Ti6Al4V) are the frequently employed materials. The computational evaluation of contact pressure was carried out using a two-dimensional axisymmetric model for UHMWPE acetabular cup paired with metal femoral head under gait cycle in this study. The results show Ti6Al4V-on-UHMWPE is able to reduce cumulative contact pressure compared to SS 316L-on-UHMWPE and CoCrMo-on-UHMWPE. Compared to Ti6Al4V-on-UHMWPE at peak loading, the difference in cumulative contact pressure to respective maximum contact pressure is 9.740% for SS 316L-on-UHMWPE and 11.038% for CoCrMo-on-UHMWPE.

Traveling with children with autism can be very challenging for parents due to their reactions to sensory stimuli resulting in behavioral problems, which lead to self-injury and danger for themselves and others. Deep pressure was reported to have a calming effect on people with autism. This study was designed to investigate the physiological effect of deep pressure, which is an autism hug machine portable seat (AHMPS) in children with autism spectrum disorders (ASD) in public transportation settings. The study was conducted with 20 children with ASD (16 boys and 4 girls) at the Semarang Public Special School with an age ranging from 4 to 13 years (mean 10.9 ± 2.26 years), who were randomly assigned into two groups. The experiment consisted of group I who used the AHMPS inflatable wraps model and group II who used the AHMPS manual pull model. Heart rate (HR) and skin conductance (SC) were analyzed to measure the physiological calming effect using pulse oximeter oximetry and a galvanic skin response (GSR) sensor. Heart rate was significantly decreased during the treatment compared to the baseline (pre-test) session in group I (inflating wrap model) with p = 0.019, while no change of heart rate variability (HRV) was found in group II (manual pull model) with p = 0.111. There was no remaining effect of deep pressure using the HRV indicator after the treatment in both groups (group I with p = 0.159 and group II with p = 0.566). GSR captured the significant decrease in skin conductance during the treatment with p < 0.0001 in group I, but no significant decrease was recorded in group II with p = 0.062. A skin conductance indicator captured the remaining effect of deep pressure (after the treatment); it was better in group I (p = 0.003) than in group II (p = 0.773). In conclusion, the deep pressure of the AHMPS inflating wrap decreases physiological arousal in children with ASD during traveling.

Children with autism spectrum disorder (ASD) have challenging behaviors, which are associated with difficulties in parenting. Deep pressure is a therapeutic modality in occupational therapy, and it was reported to produce a calming effect. This study aimed to determine whether the short-term use of an autism hug machine portable seat (AHMPS) improves behavioral and neurobiological stress in children with ASD, and to determine whether AHMPS with an inflatable wrap or manual pull is more effective. This study enrolled children with ASD who were administered with the inflatable wrap (group I) and manual pull (group II) for 20 min twice a week for 3 weeks. Conners' Parent Rating Scale-48 (CPRS-48) was used to rate behavioral improvements, and galvanic skin response (GSR) was used to measure sympathetic stress response. A total of 20 children with ASD (14 boys and 6 girls; aged 7-13 years) were included. CPRS-48 presented conduct problems: behavior was significantly decreased in the inflatable group ( p = 0.007) compared to the manual pull group. The GSR captured a significant reduction in sympathetic response ( p = 0.01) only in group I. Neurobiological stress was reduced in children who were wearing the AHMPS inflatable wrap; therefore, AHMPS inflatable wrap is an effective method to reduce emotional arousal.

Wear and wear-induced debris is a significant factor in causing failure in implants. Reducing contact pressure by using a textured surface between the femoral head and acetabular cup is crucial to improving the implant's life. This study presented the effect of surface texturing as dimples on the wear evolution of total hip arthroplasty. It was implemented by developing finite element analysis from the prediction model without dimples and with bottom profile dimples of flat, drill, and ball types. Simulations were carried out by performing 3D physiological loading of the hip joint under normal walking conditions. A geometry update was initiated based on the patient's daily routine activities. Our results showed that the addition of dimples reduced contact pressure and wear. The bottom profile dimples of the ball type had the best ability to reduce wear relative to the other types, reducing cumulative linear wear by 24.3% and cumulative volumetric wear by 31% compared to no dimples. The findings demonstrated that surface texturing with appropriate dimple bottom geometry on a bearing surface is able to extend the lifetime of hip implants.

We focused on the demonstration of a new pluripotent coffee cell culture system to control the growth and metabolic functions. Somatic cells in the epidermal layer of in vitro somatic embryos (SEs) of Coffea canephora expressed higher pluripotency to produce secondary SEs than primary or secondary meristematic tissue. SEs were ideal explants to selectively induce functionally-differentiated cell lines, both non-embryogenic callus (nEC) and embryogenic callus (EC). The protoplast co-culture bioassay method was used to explore allelopathic activity of these cultured coffee cells. Cell wall formation of lettuce protoplasts varied after five days of co-culture. A strong stimulative reaction was observed at lower nEC protoplast densities, whereas growth was inhibited at higher densities. The reaction of lettuce protoplasts after 12 days of co-culture was recognized as an inhibitory reaction of colony formation.