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The mammalian spermatozoon has many cellular compartments, such as head and tail, permitting it to interact with the female reproductive tract and fertilize the egg. It acquires this fertilizing potential during transit through the epididymis, which secretes proteins that coat different sperm domains. Optimal levels of these proteins provide the spermatozoon with its ability to move to, bind to, fuse with, and penetrate the egg; otherwise male infertility results. As few human epididymal proteins have been characterized, this work was performed to generate a database of human epididymal sperm-located proteins involved in maturation. Two-dimensional gel electrophoresis of epididymal tissue and luminal fluid proteins, followed by identification using MALDI-TOF/MS or MALDI-TOF/TOF, revealed over a thousand spots in gels comprising 745 abundant nonstructural proteins, 408 in luminal fluids, of which 207 were present on spermatozoa. Antibodies raised to 619 recombinant or synthetic peptides, used in Western blots, histological sections, and washed sperm preparations to confirm antibody quality and protein expression, indicated their regional location in the epididymal epithelium and highly specific locations on washed functional spermatozoa. Sperm function tests suggested the role of some proteins in motility and protection against oxidative attack. A large database of these proteins, characterized by size, pI, chromosomal location, and function, was given a unified terminology reflecting their sperm domain location. These novel, secreted human epididymal proteins are potential targets for a posttesticular contraceptive acting to provide rapid, reversible, functional sterility in men and they are also biomarkers that could be used in noninvasive assessments of male fertility. Molecular & Cellular Proteomics 9:2517-2528, 2010.There are two major challenges for population and reproductive health. First, rapid global population expansion, which will see the world population reach 9 billion by 2045 (http:// www.census.gov/ipc/www/idb/worldpopgraph.php). Second, infertility is suffered by around 180 million couples, comprising about 10%-15% worldwide and over 25% in some countries, of which 40%-50% is related to the male (http://www.who.int/ reproductivehealth/publications/infertility/progress_63/en/ index.html). Natural fertilization requires tightly coordinated and sequential sperm functions (1), from maturation in the epididymis (2) and survival in the female tract to fusion with the ovum (3). Fertility and infertility are both sides of the same reproductive coin so that understanding one can provide clues to the other. On the one hand, the widespread application to infertile couples of artificial reproductive technology, which bypasses natural fertilization mechanisms, has diverted attention from understanding the biological causes of the infertility for its cure, to that of overcoming the symptom of childlessness. On the other, controlling population growth by contraceptive means is currently only available to large ...

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BackgroundGeographical isolation combined with historical climatic fluctuations have been identified as two major factors that contribute to the formation of new species. On the other hand, biotic factors such as competition and predation are also able to drive the evolution and diversification of organisms. To determine whether geographical barriers contributed to population divergence or speciation in the rare endemic cicada Subpsaltria yangi the population differentiation, genetic structure and phylogeography of the species were investigated in the Loess Plateau and adjacent areas of northwestern China by analysing mitochondrial and nuclear DNA and comparing the calling song structure of 161 male individuals.ResultsThe results reveal a low level of genetic differentiation and relatively simple phylogeographic structure for this species, but two independent clades corresponding to geographically isolated populations were recognised. Genetic and geographical distances were significantly correlated among lineages. Results of divergence-time estimation are consistent with a scenario of isolation due to glacial refugia and interglacial climate oscillation in northwestern China. Significant genetic divergence was found between the population occurring in the Helan Mountains and other populations, and recent population expansion has occurred in the Helan Mountains and/or adjacent areas. This population is also significantly different in calling song structure from other populations.ConclusionsGeographical barriers (i.e., the deserts and semi-deserts surrounding the Helan Mountains), possibly coupled with related ecological differences, may have driven population divergence and allopatric speciation. This provides a possible example of incipient speciation in Cicadidae, improves understanding of population differentiation, acoustic signal diversification and phylogeographic relationships of this rare cicada species of conservation concern, and informs future studies on population differentiation, speciation and phylogeography of other insects with a high degree of endemism in the Helan Mountains and adjacent areas.Electronic supplementary materialThe online version of this article (10.1186/s12862-018-1317-8) contains supplementary material, which is available to authorized users.

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The cicada Meimuna mongolica (Distant) (Hemiptera: Cicadidae) is one of the most important pests of economic forest in Guanzhong Plain of Shaanxi Province, China. Information about ecological characteristics and some sustainable control measures of this species is urgently required for its control. In this study, nymphal instars, morphological variation, vertical distribution, and population density in soil, and emergence phenology of nymphs of M. mongolica on three main host plants (Pinus tabuliformis Carr., Populus tomentosa Carr., and Pyrus xerophila Yü) were studied, based on combined morphological and molecular identification, investigation of the first-instar nymphs hatched from eggs and others excavated from soil, and investigation of exuviae in the adult emergence period. Five nymphal instars of M. mongolica were redetermined according to the distribution plots of the head capsule widths of the nymphs. Nymphs of third and fourth instars showed morphological variation, which is closely related to host-plant association. The mean densities of nymphs in soil under the three host plants were significantly different, indicating a distinct host preference. The nymphs could extend their distribution from the 0–10 cm soil layer to the 51–60 cm soil layer underground but not beyond 60 cm soil layer under all the three host plants. The 21–30 cm soil layer under all the three host plants has the highest nymphal population density. The sex ratio of the entire population was nearly 50:50, but males dominated in the early half of the duration of the emergence. These ecological characteristics of M. mongolica could provide important information for sustainable control measures.

The cicada Hyalessa maculaticollis is widely distributed in East Asia, and is noted for its great morphological variability. The variation in this species and its allies has been a long-standing controversy. The population differentiation, genetic structure and phylogeography of this species are explored based on morphological observations, mitochondrial and nuclear DNA analyses, and comparison of the calling song structure of males. Our results reveal that the abundant intraspecific morphological variations are consistent with high levels of genetic divergence in this species, but incongruence between the morphological variations and genetic divergence is found in a few lineages. Phylogenetic and network analyses indicate that H. maculaticollis is composed of two major lineages -China and Japan. The East China Sea (ECS) land bridge acted as a dispersal corridor for H. maculaticollis during the glacial period. The climatic oscillations in the Pleistocene and the terrain structure of East Asia influenced population differentiation. The divergence time between the two sides of the East China Sea is estimated to be ∼1.05 (95% CI = 0.80-1.30) Ma, which was about the same period during which the sea level increased rapidly during the 'Ryukyu Coral Sea Stage' (0.2-1.3 Ma). Populations of H. maculaticollis are structured phylogeographically, with the China populations differentiated into a greater number of highly structured haplogroups. Qinling Mountains and the mountainous regions around the Sichuan Basin are presumed to have been major refugia for H. maculaticollis in glacial periods, and a recent population expansion has been detected for populations distributed in the area to the north of Qinling Mountains. The high degree of haplotype and nucleotide diversity shown in East China populations suggests that the flat terrain with low-altitude hills are suitable for the survival of H. maculaticollis. The species H. fuscata, treated as an independent species from H. maculaticollis by some researchers based on acoustic analyses of the calling song structure, is confirmed to be a junior synonym of H. maculaticollis based on the results of our analyses of morphological variation, calling song structure and acoustic playback experiments. Past geological events and climatic oscillations have played important roles in forming the contemporary genetic diversity Correspondence: Cong Wei, Key Laboratory of Plant Protection Resources and Pest Management, Ministry of Education, Entomological Museum,

This paper applies the convolutional long short‐term memory (convLSTM)‐based machine learning models to forecast global ionospheric total electron content (TEC) maps with up to 24 hr of lead time at a 1‐hr interval. Four convLSTM‐based models were investigated, and the one that implements the L1 loss function and the residual prediction strategy demonstrates the best performance. The convLSTM models are trained and evaluated using Center for Orbit Determination in Europe (CODE) global TEC maps over a period of nearly seven years from 19 October 2014 to 21 July 2021. Results show that the best convLSTM model outperforms the 1‐day predicted global TEC products released by CODE analysis center (c1pg) and persistence models under various levels of solar and geomagnetic activities, except for a lead time beyond 8 hr during the storm time where the c1pg has slightly better performance. The convLSTM forecasting performance degrades as the lead time increases.