Model and characteristic of a new underactuated manipulator and its simulation

The virtual prototype of the type of underactuated manipulator was established under the Solidworks. It is proved that the manipulator has the nonholonomic characteristic from the theoretical analysis to this model. The digital model was imported into ADAMS and the kinematics simulation and analysis were accomplished. The research conclusion shows that underactuated manipulator is controllable from the simulation analysis perspectives. It also provides theoretical foundation for prototypes debugging and control.     

Tumour suppressor RNF43 is a stem-cell E3 ligase that induces endocytosis of Wnt receptors

LGR5+ stem cells reside at crypt bottoms, intermingled with Paneth cells that provide Wnt, Notch and epidermal growth factor signals. Here we find that the related RNF43 and ZNRF3 transmembrane E3 ubiquitin ligases are uniquely expressed in LGR5+ stem cells. Simultaneous deletion of the two genes encoding these proteins in the intestinal epithelium of mice induces rapidly growing adenomas containing high numbers of Paneth and LGR5+ stem cells. In vitro, growth of organoids derived from these adenomas is arrested when Wnt secretion is inhibited, indicating a dependence of the adenoma stem cells on Wnt produced by adenoma Paneth cells. In the HEK293T human cancer cell line, expression of RNF43 blocks Wnt responses and targets surface-expressed frizzled receptors to lysosomes. In the RNF43-mutant colorectal cancer cell line HCT116, reconstitution of RNF43 expression removes its response to exogenous Wnt. We conclude that RNF43 and ZNRF3 reduce Wnt signals by selectively ubiquitinating frizzled receptors, thereby targeting these Wnt receptors for degradation.     

Revision of the digger wasps of the Ampulicidae and Heterogynaidae (Hymenoptera) of Saudi Arabia,with the description of a new species of the enigmatic genus Heterogyna Nagy

The apoid wasps of the families Ampulicidae and Heterogynaidae of Saudi Arabia are revised. In Ampulicidae, four species in three genera are reported, of which three species are recorded for the first time from Saudi Arabia (Al-Baha, Asir and Riyadh regions): Ampulex assimilis Kohl, Dolichurus arabicus Ohl and Trirogma caerulea Westwood. Additionally, the family Heterogynaidae is reported for the first time from Saudi Arabia (Asir and Riyadh regions), and a new species, Heterogyna saudita sp. nov., is described, diagnosed and illustrated. An illustrated key to the species of Heterogyna from the Arabian Peninsula is provided.

www.zoobank.org/urn:lsid:zoobank.org:pub:C23C70A7-AA1C-47C0-951A-D164E7B20001     

Loss-of-function variant in DNASE1L3 causes a familial form of systemic lupus erythematosus

Systemic lupus erythematosus (SLE) is a complex autoimmune disease that causes substantial morbidity. As is typical for many other multifactorial disorders, much of the heritability of SLE remains unknown. We identified a rare autosomal recessive form of SLE, in which autozygome analysis revealed a null mutation in the DNASE1L3 gene. The DNASE1L3-related SLE we describe was always pediatric in onset and correlated with a high frequency of lupus nephritis. Our findings confirm the critical role of impaired clearance of degraded DNA in SLE pathogenesis.     

New approaches for sampling and modeling native and exotic plant species richness

We demonstrate new multi-phase, multi-scale approaches for sampling and modeling native and exotic plant species to predict the spread of invasive species and aid in control efforts. Our test site is a 54,000-ha portion of Rocky Mountain National Park, Colorado, USA. This work is based on previous research wherein we developed vegetation sampling techniques to identify hot spots of diversity, important rare habitats, and locations of invasive plant species. Here we demonstrate statistical modeling tools to rapidly assess current patterns of native and exotic plant species to determine which habitats are most vulnerable to invasion by exotic species. We use stepwise multiple regression and modified residual kriging to estimate numbers of native species and exotic species, as well as probability of observing an exotic species in 30 × 30-m cells. Final models accounted for 62% of the variability observed in number of native species, 51% of the variability observed in number of exotic species, and 47% of the variability associated with observing an exotic species. Important independent variables used in developing the models include geographical location, elevation, slope, aspect, and Landsat TM bands 1-7. These models can direct resource managers to areas in need of further inventory, monitoring, and exotic species control efforts.     

Bilirubin sensor based on CuO-CdO composites deposited in a nafion/glassy carbon electrode matrixes

Copper oxide-cadmium oxide nanocomposites(CuO-CdO NCs) were synthesized by solvothermal technique in a basic medium. CuO-CdO NCs were characterized using conventional techniques, such as Fourier Transform Infrared Spectroscopy(FTIR), UV–Visible Spectroscopy(UV/Vis), Field-Emission Scanning Electron Microscopy(FESEM), X-ray electron dispersive spectroscopy(XEDS), X-ray photoelectron spectroscopy(XPS), and powder X-ray diffraction(XRD). A selective and enzyme-less Bilirubin(BLR) sensor was developed with a thin-layer of NCs onto a glassy carbon electrode(GCE, surface area = 0.0316 cm~2) using 5% nafion binders at room conditions. Improved electrochemical performances of higher sensitivity, lower detection limit,linear dynamic range(LDR), and long-term stability of preferred BLR were achieved by a reliable currentvoltage(I-V) approach. The calibration curve was found linear(R~2= 0.9347) in a wide range of BLR concentration(10.0 pM ~ 10.0 mM). Based on the signal to noise ratio value of 3, the sensitivity and limit of detection(LOD) of the sensor were calculated as 95.0 pA μM~(-1) cm~(-2) and 1.0 ± 0.1 pM respectively.Solvothermally synthesized CuO-CdO NCs/GCE is an excellent advancement of developing a selective and sensitive BLR sensor by electrochemical approach and practically implemented in real sample applications.     

多项式系最大公因子的并行算法

基于并行计算的思想,给出一般域上多项式系最大公因子的两种算法.给出了其伪码表述,证明了其可行性,并给出了基于符号演算的程序实现及计算实例.结果表明:该算法可并行计算,计算速度优于串行算法;该算法是一种直接方法,不同于基于多项式对的间接方法;该算法是精确算法,因此既可用于数值计算,也可用于符号演算.同时,对已有的伪码表述...     

流动注射分析法测定氨基酸和蛋白质扩散系数的研究

提出了用盘曲管道流动注射分析以半峰宽测定扩散系数的理论模型和实验方法，测定了一些小分子化合物和蛋白质样品的扩散系数，每次测定所需时间为１０－３０ｍｉｎ，提出了用该方法扩散系数测定蛋白质分子量的新方案并测定了一些蛋白质样品的分子量。     

Neurons in medial prefrontal cortex signal memory for fear extinction

Conditioned fear responses to a tone previously paired with a shock diminish if the tone is repeatedly presented without the shock, a process known as extinction. Since Pavlov it has been hypothesized that extinction does not erase conditioning, but forms a new memory. Destruction of the ventral medial prefrontal cortex, which consists of infralimbic and prelimbic cortices, blocks recall of fear extinction, indicating that medial prefrontal cortex might store long-term extinction memory. Here we show that infralimbic neurons recorded during fear conditioning and extinction fire to the tone only when rats are recalling extinction on the following day. Rats that froze the least showed the greatest increase in infralimbic tone responses. We also show that conditioned tones paired with brief electrical stimulation of infralimbic cortex elicit low freezing in rats that had not been extinguished. Thus, stimulation resembling extinction-induced infralimbic tone responses is able to simulate extinction memory. We suggest that consolidation of extinction learning potentiates infralimbic activity, which inhibits fear during subsequent encounters with fear stimuli.