Wheat blue dwarf disease (WBD) was first reported in China in the 1960s. It has caused severe losses on several occasions in winter wheat (Triticum aestivum) in northwestern China, and the nature of the pathogenic agent has been unknown. Here we have shown that WBD was caused by a 16SrI-C phytoplasma transmitted by Psammotettix striatus. This finding was based on molecular diagnostics, insect transmission trials, and host-range determination. Portions of the 16S rRNA and ribosomal protein (rp) genes, rpsS (rps19), rplV (rpl22), and rpsC (rps3), were amplified from DNA samples of WBD-infected wheat seedlings by polymerase chain reaction (PCR) utilizing phytoplasma specific primer pairs. The nucleotide sequences of these amplicons showed high identity to these genes from phytoplasma strains in the aster yellows group (16SrI). Pairwise nucleotide sequence identities of WBD 16S rDNA compared to representative genes of 16SrI group strains ranged from 98.9 to 99.9%, whereas compared to 17 other phytoplasma groups (16SrII to 16SrXVIII), sequence identity ranged from 88.6 to 96.0%. Similarly, the sequence identities of rps19, rpl22, and rps3 between WBD and 16SrI group strains varied from 96.6 to 99.7%, but only 60.3 to 65% between WBD and other phytoplasma groups. Phylogenetic analyses were carried out on sequences from 16S rRNA and ribosomal protein genes (rps19, rpl22, and rps3), respectively, and both results indicated that WBD phytoplasma was a member of the 16SrI group and most closely related to subgroup 16SrI-C. WBD-infected P. striatus were present in wheat fields with WBD, and phytoplasma infection was verified by PCR detection followed by DNA sequencing. Insect transmission trials confirmed that P. striatus transmitted the WBD phytoplasmal agent from infected wheat to healthy wheat seedlings and seven other different plant species in the greenhouse. A survey of various weed species near WBD-infected wheat fields found 10 plant species in seven families to be positive for the presence of WBD phytoplasma.

Liu Q, Zhang N, Li Z, He H. Efficacy of autologous platelet-rich plasma gel in the treatment of refractory pressure injuries and its effect on wound healing time and patient quality of life. Clinics (Sao Paulo).

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The effect of fuel type, fuel molar concentration, and air molar concentration on the autoignition temperature (AIT) of n-heptane, methanol, ethanol, and butanol, under a wide range of conditions (φ = 0.4–2.0, P init = 80–500 psi), is investigated using a constant volume bomb. The results indicate that the AIT generally decreases as the chain length and molecular weight each increase. The AIT decreases as the fuel molar concentration, as well as air molar concentration, increase. The AIT of n-heptane remains approximately constant (280 °C) as the fuel/air molar concentration increase. While the AIT of methanol, ethanol, and butanol decrease from 548 °C to 479 °C, from 450 °C to ∼371 °C, and from 401 to 342 °C, respectively, with increasing fuel/air molar concentration. Numerical study is performed to identify the cause of AIT variation using validated comprehensive reaction mechanisms of n-heptane and methanol. The AIT of n-heptane remains almost constant under wide parameters, because of the low activation energy and multiple reaction pathways of keto-hydroperoxides formation and decomposition, which are the chain branching reactions of n-heptane low-temperature oxidation. Conversely, the AIT of methanol is susceptible to external factors such as fuel/air molar concentration may be attributed to the high energy barriers and relatively simple routes of H atom abstraction from methanol by hydroperoxyl radical and hydrogen peroxide decomposition, which are the chain branching reactions of methanol oxidation.

The growing spectrum crunch has motivated exploratory efforts in the use of LTE in the 5GHz ISM bands for downlink traffic. However, this paradigm raises concerns of fair sharing of the spectrum and the adverse impact of scheduled LTE frames on Wi-Fi Packet Success Rates (PSR). To address this issue, we propose E-Fi, an interference-evasion mechanism that allows Wi-Fi devices to survive LTE transmissions without any cooperation between these two different standards. Different from existing approaches, we argue that the simple use of Almost Blank Subframes (ABS) within the LTE standard offering short channel access windows overestimates opportunities for Wi-Fi. The pilots embedded in the ABS not only interfere with Wi-Fi but also adversely impact the carrier sensing function. E-Fi mitigates this problem through a two-fold approach. It uses a combination of (i) Wi-Fi Direct with packet relaying and (ii) classical distributed coordination function to reach distant nodes. Second, it ensures load balancing for both Wi-Fi uplink and downlink traffic with high PSR by creating node-groups based with dedicated contention-based medium access intervals. Our approach is validated by comprehensive simulation and experimental results that indicate significantly higher throughput in E-Fi compared to classical Wi-Fi.

A new variant of grapevine berry inner necrosis virus (GINV) was identified by sequencing of small RNA extracted from 'Beta' and Thompson seedless grapevines showing leaf mottle and ring spot symptoms. However, GINV was not found in symptomless samples used as a control. The complete genome sequences of two GINV isolates (KU234316-17) were determined, and these showed 75.76-89.74% sequence identity to the genome of a previously reported Japanese GINV isolate. The new variants appear to be evolutionarily distinct from the original GINV isolate. This is the first report of GINV outside of Japan.

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