Sympathy and Punishment: Evolution of Cooperation in Public Goods Game

An important way to maintain human cooperation is punishing defection. However, since punishment is costly, how can it arise and evolve given that individuals who contribute but do not punish fare better than the punishers? This leads to a violation of causality, since the evolution of punishment is prior to the one of cooperation behaviour in evolutionary dynamics. Our public goods game computer simulations based on generalized Moran Process, show that, if there exists a \'behaviour-based sympathy\' that compensates those who punish at a personal cost, the way for the emergence and establishment of punishing behaviour is paved. In this way, the causality violation dissipates. Among humans sympathy can be expressed in many ways such as care, praise, solace, ethical support, admiration, and sometimes even adoration; in our computer simulations, we use a small amount of transfer payment to express \'behaviour-based sympathy\'. Our conclusions indicate that, there exists co-evolution of sympathy, punishment and cooperation. According to classical philosophy literature, sympathy is a key factor in morality and justice is embodied by punishment; in modern societies, both the moral norms and the judicial system, the representations of sympathy and punishment, play an essential role in stable social cooperation.Public Goods Game, Cooperation, Social Dilemma, Co-Evolution, Sympathy, Punishment

A tunable plasmonic refractive index sensor with nanoring-strip graphene arrays

In this paper, a tunable plasmonic refractive index sensor with nanoring-strip graphene arrays is numerically investigated by the finite difference time domain (FDTD) method. The simulation results exhibit that by changing the sensing medium refractive index nmed of the structure, the sensing range of the system is large. By changing the doping level ng, we noticed that the transmission characteristics can be adjusted flexibly. The resonance wavelength remains entirely the same and the transmission dip enhancement over a big range of incidence angles [0,45] for both TM and TE polarizations, which indicates that the resonance of the graphene nanoring-strip arrays is insensitive to angle polarization. The above results are undoubtedly a new way to realize various tunable plasmon devices, and may have a great application prospect in biosensing, detection and imaging

Numerical Simulation and Experimental Examination of an Oldham Coupling

In scroll compressors, the Oldham couplings have typically been formed of aluminum alloy and have often broken issues due to the higher force that transmitted to Oldham coupling by the orbiting scroll. This problem was especially pronounced in scroll compressors and in particular during flooded start or slug conditions.  So, to enhance Oldham coupling’s strength performance in above conditions becomes an important work to Engineers. In this paper, about 30 pcs failed Oldham couplings which were broken in by flood start or slug conditions were investigated. Meanwhile, Oldham coupling’s stress distribution and deformation were simulated in ANSYS software. High stress zones and weak positions were got; potential failure risks were also reappeared in the simulation. After simulation, two optimized proposals were stated and simulated. And then, corresponding prototypes were made and sent to test together with mass production parts in lab. Tests results indicate new design’s strength performances were improved and highly aligned with numerical simulation results. But, some test errors were also found between mass production parts and prototypes. The factors which can impact errors and their weight were analyzed and calculated. In the end, a prediction model of using numerical model to estimate mass production part performance is given in this paper.

Dynamic comparison between Daan real-time PCR and Cobas TaqMan for quantification of HBV DNA levels in patients with CHB

BACKGROUND: Hepatitis B virus (HBV) DNA levels are crucial for managing chronic hepatitis B (CHB). It was unclear whether Daan real-time polymerase chain reaction test (Daan test) or COBAS TaqMan HBV DNA Test (Cobas TaqMan) was superior in measuring different HBV DNA levels in clinical specimens. METHODS: We enrolled 67 treatment-naïve, HBV surface antigen-positive CHB patients (high baseline viral levels) who received either lamivudine/adefovir or entecavir. Serum samples were tested at baseline and treatment week 24 using the Daan test and Cobas TaqMan. RESULTS: In the 67-baseline samples, the HBV DNA levels with the Cobas TaqMan (7.90 ± 0.73 log(10) IU/mL) were significantly greater than those of the Daan test (7.11 ± 0.44 log(10) IU/mL; P < 0.001). Of the 67 24-week samples (low viral levels), the Cobas TaqMan detected 59 (88.1%; 8 undetected); the Daan test detected 33 (49.3%; 34 undetected; P < 0.001). The Cobas TaqMan detected HBV DNA in 26 of 34 samples undetectable by the Daan test (range, 1.4–3.7 log(10) IU/mL) or 38% of samples (26/67). The reductions in viral load after 24 weeks of oral antiviral treatment in the 33 samples that were positive for both the Daan test and the Cobas TaqMan test were significantly different (3.59 ± 1.11 log(10) IU/mL versus 4.87 ± 1.58 log(10) IU/mL, respectively; P = 0.001). Spearman correlation analysis showed positive correlation between results from two tests (r(p) = 0.602,P<0.001). The HBV genotypes and the anti-viral treatment did not affect the measurements of the HBV DNA by the Daan assay and the Cobas Taqman assay. CONCLUSION: The Cobas Taqman was more sensitive at low viral loads than the Daan test and the change from complete to partial virological response could affect clinical decisions. The Cobas Taqman may be more appropriate for detection of HBV DNA levels

Tooth Surface Reconstruction and Tooth Profile Geometric Analysis of Circular Arc Tooth Trace Cylindrical Gears

To reconstruct the tooth surface of a circular arc tooth trace cylindrical gear (CATT gear), one needs to create an accurate 3D model and investigate geometric features of the tooth profile. According to the processing principle of the rotating knife dish milling, and using the space meshing theory and differential geometry, the tooth surface equation and the tooth profile of CATT gears have been deduced. Then, the tooth surface reconstruction of CATT gears was done and a 3D model was created. Next, based on theoretical deduction, it was proven that the profile of the middle section was involute, and the other section was hyperbolic. Finally, the influences of the design parameters on the tooth profile were investigated. The general tendency is that the gear tooth thickness becomes thinner as the gear width increases and the tooth line radius decreases, and the tooth profiles of the concave and the convex tooth surface may intersect. The influences of the module need to be discussed separately. The tooth thickness deviation increases as the module increases. But the relative tooth thickness deviation is opposite. Therefore, it is suggested that RT>= (3-4)b and the module should be large to improve the bearing capacity. The results of the investigation provide a reference for the design, profile modification, lubrication, and measuring of CATT gears