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The formation of hematopoietic cells relies on the chromatin remodeling activities of ISWI ATPase SMARCA5 (SNF2H) and its complexes. The Smarca5 null and conditional alleles have been used to study its functions in embryonic and organ development in mice. These mouse model phenotypes vary from embryonic lethality of constitutive knockout to less severe phenotypes observed in tissue-specific Smarca5 deletions, e.g., in the hematopoietic system. Here we show that, in a gene dosage-dependent manner, the hypomorphic allele of SMARCA5 (S5tg) can rescue not only the developmental arrest in hematopoiesis in the hCD2iCre model but also the lethal phenotypes associated with constitutive Smarca5 deletion or Vav1iCre-driven conditional knockout in hematopoietic progenitor cells. Interestingly, the latter model also provided evidence for the role of SMARCA5 expression level in hematopoietic stem cells, as the Vav1iCre S5tg animals accumulate stem and progenitor cells. Furthermore, their hematopoietic stem cells exhibited impaired lymphoid lineage entry and differentiation. This observation contrasts with the myeloid lineage which is developing without significant disturbances. Our findings indicate that animals with low expression of SMARCA5 exhibit normal embryonic development with altered lymphoid entry within the hematopoietic stem cell compartment. This transgenic mouse study based on different protein levels of the ISWI ATPase SMARCA5 shows accumulation of multipotent hematopoietic progenitors with block of B and T lymphopoiesis and, to a lesser extent, erythropoiesis at low SMARCA5 levels. [ABSTRACT FROM AUTHOR]

The article deals with sensor fusion and real-time calibration in a homogeneous inertial sensor array. The proposed method allows for both estimating the sensors' calibration constants (i.e., gain and bias) in real-time and automatically suppressing degraded sensors while keeping the overall precision of the estimation. The weight of the sensor is adaptively adjusted according to the RMSE concerning the weighted average of all sensors. The estimated angular velocity was compared with a reference (ground truth) value obtained using a tactical-grade fiber-optic gyroscope. We have experimented with low-cost MEMS gyroscopes, but the proposed method can be applied to basically any sensor array. [ABSTRACT FROM AUTHOR]

Odometry is one of most-used techniques used in mobile robotics and autonomous vehicles, especially when the indoor navigation is required or when robot or vehicle moves inside the tunnel. The output of the odometer is usually a count of pulses corresponding to the distance run by given wheel. Due to the quantization noise, estimation of the velocity (first derivative of the distance) is challenging. This article is focused on curve-fitting filter used for the speed estimation and optimization of its parameters, considering the physical constraints of the robot, sampling frequency of the system and the quantization step. The paper proposes an empirical formula for estimating the optimal parameters of the curve fitting filter. The optimized filter has been evaluated using both simulation and real experiment and compared with several standard differentiation methods. [ABSTRACT FROM AUTHOR]