When does the female bias arise? Insights from the sex determination cascade of a flea beetle with a strongly skewed sex ratio.

Reproduction-manipulating bacteria like Wolbachia can shift sex ratios in insects towards females, but skewed sex ratios may also arise from genetic conflicts. The flea beetle Altica lythri harbors three main mtDNA strains that are coupled to three different Wolbachia infections. Depending on the mtDNA types, the females produce either offspring with a balanced sex ratio or exclusively daughters. To obtain markers that can monitor when sex bias arises in the beetle's ontogeny, we elucidated the sex determination cascade of A. lythri. We established a RT-PCR method based on length variants of dsx (doublesex) transcripts to determine the sex of morphologically indistinguishable eggs and larvae. In females of one mtDNA type (HT1/HT1*) known to produce only daughters, male offspring were already missing at the egg stage while for females of another type (HT2), the dsx splice variants revealed a balanced sex ratio among eggs and larvae. Our data suggest that the sex determination cascade in A. lythri is initiated by maternally transmitted female-specific tra (transformer) mRNA as primary signal. This tra mRNA seems to be involved in a positive feedback loop that maintains the production of the female splice variant, as known for female offspring in Tribolium castaneum. The translation of the maternally transmitted female tra mRNA must be inhibited in male offspring, but the underlying primary genetic signal remains to be identified. We discuss which differences between the mtDNA types can influence sex determination and lead to the skewed sex ratio of HT1.

The blind spot of online creative idea generation studies: A perspective of media materiality.

Online creative idea generation is often considered an extension of traditional creative idea activities on the Internet platform, in which digital technology plays an important role. Consistent with the studies on traditional creative idea activities, the studies on online creative idea generation take the creativity of mass psychology as the core, and believe that digital technology can stimulate people's creative output. This study challenges the past research paradigm from the perspective of media materiality, redefines the processes and activities of online creative idea generation, and further suggests that it may affect people's psychology by reducing their creativity without real awareness. The study is innovative in both theory and practice. We also discuss the limitations and future directions of the study.

Improved Dynamic Window Approach for Unmanned Surface Vehicles' Local Path Planning Considering the Impact of Environmental Factors.

The aim of local path planning for unmanned surface vehicles (USVs) is to avoid unknown dynamic or static obstacles. However, current relative studies have not fully considered the impact of ocean environmental factors which significantly increase the control difficulty and collision risk of USVs. Therefore, this work studies two ocean environmental factors, namely, wave and current, given that they both have a significant impact on USVs. Furthermore, we redesign a kinematic model of an USV and the evaluation function of a classical and practical local path planning method based on the dynamic window approach (DWA). As shown by the results of the simulations, the path length was impacted mainly by the intensity of the environmental load and slightly by the direction of the environmental load, but the navigation time was significantly influenced by both. Taking the situation in still water as a benchmark in terms of the intensity and direction of the environmental factors, the maximum change rates of the path length were 8.6% and 0.6%, respectively, but the maximum change rates of the navigating time were 17.9% and 25.6%, separately. In addition, the average calculation time of each cycle was only 0.0418 s, and the longest time did not exceed the simulation time corresponding to a single cycle of 0.1 s. This method has proven to be a good candidate for real-time local path planning of USVs since it systematically considers the impact of waves and currents on the navigation of USVs, and thus ensures that USVs can adjust to the planned path in time and avoid obstacles when navigating in the real ocean environment.

MOFs-Derived Flower-Like Hierarchically Porous Zn-Mn-Se/C Composite for Extraordinary Rate Performance and Durable Anode of Sodium-Ion and Potassium-Ion Batteries.

The slow kinetics and poor structural stability prevent transition metal selenides from being widely used in sodium-ion batteries (SIBs) and potassium-ion batteries (PIBs). Herein, the "flower-like" porous carbon anchored by Zn-Mn binary selenides (ZMS@FC) composites are fabricated by selenizing the modified hierarchically metal-organic frameworks. The 2D conductive hierarchically flakes' abundant pore structure and multiple active sites shorten the ion diffusion length and promote conductivity, while the synergistic effect of the binary metals and intrinsic large pseudocapacitive contribution effectively improve capacity and rate performance. ZMS@FC composites exhibit impressive rate capability of 294.4 mA h g-1 at 10 A g-1 and excellent cyclic stability with 369.6 mA h g-1 specific capacity retention at 2 A g-1 after 1000 cycling in SIBs. It is noted that 156.9 mA h g-1 can be retained at 5 A g-1 and 227.0 mA h g-1 is remained after 500 cycles at 2 A g-1 in PIBs. The ex situ X-ray diffraction patterns and transmission electron microscopy pictures are used to confirm the conversion reaction processes of the Zn-Mn-Se. Designing high-performance energy storage materials may benefit greatly from the universal synthesis technology of bimetallic sulfide anodes for enhanced SIBs and PIBs.

[Identification of chemical components of mahuang decoction by GC-MS and UPLC-Q-TOF-MS].

Since the polyjuice potion ingredient is complex, we need to develop an analysis method with well separation and high stability to perform qualitative analysis. After dividing chemical components of Mahuang Decoction into fat-soluble and water-soluble constituents by gradient extraction, GC-MS was used to analyze the chemical components of the ethyl acetate extraction. The results showed that forty compounds had been identified by NIST MS search 2.0 standard mass spectrometry Library and literatures. Next, UPLC-Q-TOF-MS was applied to idendify the chemical components of the water extraction. The results showed that thirty-nine compounds had been identified by MZmine-2.9.1, Isotope Pattern, fragmentation regularity of mass spectrometry and literatures. This experiment will provide evidences for elucidation of the effective substance in Mahuang decoction and can be used as a simple, shortcut method for analysis and identification for the polyjuice potion.

Evolution of rapid development in spadefoot toads is unrelated to arid environments.

The extent to which species' life histories evolve to match climatic conditions is a critical question in evolutionary biology and ecology and as human activities rapidly modify global climate. GIS-based climatic data offer new opportunities to rigorously test this question. Superficially, the spadefoot toads of North America (Scaphiopodidae) seem to offer a classic example of adaptive life-history evolution: some species occur in extremely dry deserts and have evolved the shortest aquatic larval periods known among anurans. However, the relationships between the climatic conditions where spadefoots occur and the relevant life-history traits have not been explicitly tested. Here, we analyzed these relationships using GIS-based climatic data, published life-history data, and a time-calibrated phylogeny for pelobatoid frogs. Surprisingly, we find no significant relationships between life-history variables and precipitation or aridity levels where these species occur. Instead, rapid development in pelobatoids is strongly related to their small genome sizes and to phylogeny.

Changes of the spectrum on thyroid disease after the ten-year implementation of universal salt iodization in Guangxi Zhuang Autonomous Region / 中华流行病学杂志

<p><b>OBJECTIVE</b>To reveal the relationship between iodine nutrition and the change of spectrum on thyroid diseases through comparing the different iodine environments pre- and post- the universal salt iodization(USI)campaign.</p><p><b>METHODS</b>To compare the urinary iodine concentration between 1000 normal people and 5998 patients with thyroid disease who had undergone surgical operations, from 4 major cities, including iodine deficient and rich areas of Guangxi Zhuang Autonomous Region.</p><p><b>RESULTS</b>After USI was put into practice, the urinary iodine concentration of patients with thyroid appeared higher than those of normal people(324.3 µg/L vs. 238.5 µg/L, P < 0.05). The urinary iodine concentrations of nodular goiter,Graves disease, toxic nodular goiter, thyroid papillary carcinoma and Hashimoto's thyroiditis were higher than those before the USI was taken(263.8 µg/L vs. 69.75 µg/L, 289.7 µg/L vs. 228.3 µg/L, 346.8 µg/L vs. 268.4 µg/L, 350.3 µg/L vs. 316.2 µg/L and 378.5 µg/L vs. 305.8 µg/L). The proportions of toxic nodular goiter, thyroid papillary carcinoma and Hashimoto's thyroiditis appeared as 7.59% vs. 4.80%, 5.85% vs. 4.02% and 3.88% vs. 2.46%, all higher than those before the implementation of USI, except the nodular goiter which showed a reduction (63.56% vs. 69.75%).</p><p><b>CONCLUSION</b>The spectrum of thyroid diseases appeared an obvious change in Guangxi within the last 10-year implementation of USI. However, the excessive intake of iodine might serve as a risk factor for toxic nodular goiter, thyroid papillary carcinoma and Hashimoto's thyroiditis.</p>