The common nodulation genes of Astragalus sinicus rhizobia are conserved despite chromosomal diversity

The nodulation genes of Mesorhizobium sp. (Astragalus sinicus) strain 7653R were cloned by functional complementation of Sinorhizobium meliloti nod mutants. The common nod genes, nodD, nodA, and nodBC, were identified by heterologous hybridization and sequence analysis. The nodA gene was found to be separated from nodBC by approximately 22 kb and was divergently transcribed. The 2.0-kb nodDBC region was amplified by PCR from 24 rhizobial strains nodulating A. sinicus, which represented different chromosomal genotypes and geographic origins. No polymorphism was found in the size of PCR products, suggesting that the separation of nodA from nodBC is a common feature of A. sinicus rhizobia. Sequence analysis of the PCR-amplified nodA gene indicated that seven strains representing different 16S and 23S ribosomal DNA genotypes had identical nodA sequences. These data indicate that, whereas microsymbionts of A. sinicus exhibit chromosomal diversity, their nodulation genes are conserved, supporting the hypothesis of horizontal transfer of nod genes among diverse recipient bacteria

Acute and long-term effects of Δ9-tetrahydrocannabinol on object recognition and anxiety-like activity are age- and strain-dependent in mice

Use of exogenous cannabinoids disrupts the fine-tuned endocannabinoid receptor system, possibly leading to alterations in cognition, memory, and emotional processes that endure long after cannabinoid use has stopped. Long-term adolescent use may uniquely disrupt these behaviors when compared to adult use. The current study explored the acute and long-term behavioral effects of six 10mg/kg Δ9-tetrahydrocannabinol (THC) injections across the adolescent or early adult period in male inbred C57Bl/6J and DBA/2J mice. The acute and prolonged effects of THC on object memory using the novel object recognition task, unconditioned anxiety in the elevated plus maze and open field, and sedative effects in the open field were examined. Acute THC treatment resulted in anxiogenic activity in both strains, but only caused sedation in B6 mice. Repeated THC treatment resulted in a protracted effect on object recognition, but not unconditioned anxiety, assessed 4weeks later. In both strains, an adolescent history of THC treatment disrupted later object recognition. Interestingly, in B6 mice an adult history of THC exposure appeared to rescue a deficit in object recognition observed in vehicle-treated adults. Repeated THC administration also produced a protracted effected on CB1R protein expression. Animals treated with THC in adolescence maintained increased levels of CB1R protein expression compared to their adult THC-treated counterparts at five weeks following the last injection. These results indicate that THC use may have long-lasting effects with adolescence being a unique period of susceptibility

Metastable behavior of vortex matter in the electronic transport processes of homogenous superconductors

We study numerically the effect of vortex pinning on the hysteresis voltage-temperature (V-T) loop of vortex matter. It is found that different types of the V-T loops result from different densities of vortex pinning center. An anticlockwise V-T loop is observed for the vortex system with dense pinning centers, whereas a clockwise V-T loop is brought about for vortices with dilute pinning centers. It is shown that the size of the V-T loop becomes smaller for lower experimental speed, higher magnetic field, or weak pinning strength. Our numerical observation is in good agreement with experiments

Approximation algorithms for the parallel flow shop problem

We consider the NP-hard problem of scheduling n jobs in m two-stage parallel flow shops so as to minimize the makespan. This problem decomposes into two subproblems: assigning the jobs to parallel flow shops; and scheduling the jobs assigned to the same flow shop by use of Johnson's rule. For m = 2, we present a 32-approximation algorithm, and for m = 3, we present a 127-approximation algorithm. Both these algorithms run in O(n log n) time. These are the first approximation algorithms with fixed worst-case performance guarantees for the parallel flow shop problem

CP-AGCN: Pytorch-based Attention Informed Graph Convolutional Network for Identifying Infants at Risk of Cerebral Palsy

Early prediction is clinically considered one of the essential parts of cerebral palsy (CP) treatment. We propose to implement a low-cost and interpretable classification system for supporting CP prediction based on General Movement Assessment (GMA). We design a Pytorch-based attention-informed graph convolutional network to early identify infants at risk of CP from skeletal data extracted from RGB videos. We also design a frequencybinning module for learning the CP movements in the frequency domain while filtering noise. Our system only requires consumer-grade RGB videos for training to support interactive-time CP prediction by providing an interpretable CP classification result

Statistics of skyrmions in Quantum Hall systems

We analyze statistical interactions of skyrmions in the quantum Hall system near a critical filling fraction in the framework of the Ginzburg-Landau model. The phase picked up by the wave-function during an exchange of two skyrmions close to $\nu=1/(2n+1)$ is $\pi[S+1/2(2n+1)]$, where $S$ is the skyrmion's spin. In the same setting an exchange of two fully polarized vortices gives rise to the phase $\pi/(2n+1)$. Skyrmions with odd and even numbers of reversed spins have different quantum statistics. Condensation of skyrmions with an even number of reversed spins leads to filling fractions with odd denominators, while condensation of those with an odd number of reversed spins gives rise to filling fractions with even denominators.Comment: 6 pages in Latex. addendum - skyrmions with odd or even number of reversed spins have different quantum statistics. They condense to form respectively even or odd denominator filling fraction state

Associative effects in diets composed of alfalfa and corn soybean concentrate fed to growing cashmere goats

The associative effects resulting from the proportions of neutral detergent fibre (NDF) and non fibre  carbohydrate (NFC) were explored and assessed by in vitro gas production . Total mixed rations (TMR)  composed primarily of alf a lfa and corn soybean concentrate were fed to growing cashmere goats. Treatments were defined by three proportions of NFC and NDF namely 2.00 ( TMR1), 2.35 ( TMR2), and 3.00 ( that were used to grow cashmere goats , and these TRMs were incubated for 48 h ours to evaluate their influence on  associative effects. The results indicated that the associative influences of these treatments on gas production  occurred within the cultures predominantly at 2 8 hours, and disappeared gradually as culture time was ex tended . TMR 2 and TMR3 incubation increased gas production compared with that observed in the other groups at all incubation times P > 0.05), and these groups exhibited positive associative effects, particularly during the early hours of incubation P <0.05 )). TMR 3 displayed the best associative effect

Quantum teleportation of light beams

We experimentally demonstrate quantum teleportation for continuous variables using squeezed-state entanglement. The teleportation fidelity for a real experimental system is calculated explicitly, including relevant imperfection factors such as propagation losses, detection inefficiencies and phase fluctuations. The inferred fidelity for input coherent states is F = 0.61 +- 0.02, which when corrected for the efficiency of detection by the output observer, gives a fidelity of 0.62. By contrast, the projected result based on the independently measured entanglement and efficiencies is 0.69. The teleportation protocol is explained in detail, including a discussion of discrepancy between experiment and theory, as well as of the limitations of the current apparatus.Comment: 17 pages, 19 figures, submitted to PR

Electromagnetic ultrasonic guided wave long-term monitoring and data difference adaptive extraction method for buried oil-gas pipelines

An increasing number of buried oil-gas pipelines are generated in recent years and defects occur with higher probability in their long-running process. This work proposes an electromagnetic ultrasonic guided wave (EUGW) long-term monitoring scheme for buried oil-gas pipelines and a data difference adaptive extraction method for the monitoring data. The T (0,1) mode guided wave is selected because of its non-dispersive characteristic. For the electromagnetic acoustic transducer (EMAT), a circumferentially magnetized nickel strap is bonded on the pipe to provide the bias magnetic field and the excitation coils are winded on the nickel strap to provide the dynamic magnetic field. A detection stub is planted on the ground and the connector of buried coils is installed in the stub. The difference array is constructed and adaptive gain and attenuation are performed in the data difference adaptive extraction method. The EUGW long-term monitoring scheme is on-site applied for buried oil pipes in Jinan city, Shandong province, China. The EMAT is installed and buried with the pipe, and the periodical detection is conducted from December 2015 till now, once per month. A pit is found and verified by excavation at the distance 9.25 m from the buried EMAT on the flow direction. On-site detection results show that the data extraction method can dramatically improve the signal to noise ratio of the monitoring data and accurately extract the difference and variation of the pipe's structural health condition that occurred in the long-term service. The EUGW long-term monitoring scheme is proved to be a feasible method with prosperous prospect for the structural health monitoring of buried oil-gas pipelines