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The development of breast cancer is usually related to multiple pathways. A combinatory therapeutic system that combines drug/siRNA targeting several independent pathways has become an attractive approach to reduce the side effects and improve the efficiency of antitumor drugs. Herein, we designed a unique micelle-liposome hybrid nanoparticle platform for the combinatory administration of the cytotoxic drug DOX and Sphk2-siRNA for the treatment of multidrug-resistant (MDR) cancer. The synthesized lipid dioleoyl ethanolamine (DE) and pH-responsive DOPE were used to produce DOX/siRNA co-loaded hybrid nanoparticle (DOX-MC-siSphk2/ASLNP), with high drug-loading capacity and transfection efficacy. We demonstrated that simultaneous cellular endocytosis of DOX/siRNA induced by nanoparticles in MCF-7/ADR cells could acquire higher drug cytotoxicity and contribute to increasing the apoptosis of tumor cell. Furthermore, DOX-MC-siSphk2/ASLNP could significantly block the tumor growth of MDR breast cancer in xenograft mouse model with lower cardiotoxicity.

Using multiple proxy data of historical hydroclimate variations, this study first selects the five heaviest megadrought decades in North China during the last millennium and then depicts the spatial pattern of hydroclimate over the Northern Hemisphere through these five megadrought decades. The results shows that abnormally dry conditions existed in East Asia, North America, and Europe when megadroughts in North China during the last millennium. The intensity of dry conditions in North America was stronger than that in Europe. Then, through comparing the spatial patterns of hydroclimate from proxy data with ensemble modeling of nine CMIP5/PMIP3 models, we find that such megadroughts in North China, and the contemporaneously abnormal dry conditions over the Northern Hemisphere were very likely mainly induced by external forcing, i.e., large volcanic eruptions and weakened solar irradiation. These external forcing may lead to climate cooling and, hence, air motion downward at mid-lower layer of troposphere, inducing a much more stable troposphere; as well as, the land-ocean pressure differences were weakened, and, hence, there would be decreased water vapor flux from ocean to land. Both of intensified stability of troposphere and weakened vapor transportations to land would lead to precipitation decline and, as a result, would be favorable for drought. It is therefore necessary to consider these external forcing into future climate change predicting to improve our ability of predicting megadrought.

An extreme drought occurred from 1876 to 1878 in most regions of northern China, leading to a series of social impacts, including harvest failures, price inflation, and population migration. Most regions of the Northern Hemisphere concurrently experienced extreme drought. Here, we use reconstructed high-resolution hydroclimatic (Palmer Drought Severity Index/precipitation) datasets and investigate the seasonal–annual hydroclimatic spatial patterns and drought intensity in North China from 1876 to 1878. Furthermore, we select combined sea surface temperature (SST) modes with positive Indian Ocean Dipole (IOD)/Pacific Decadal Oscillation (PDO) and El Nino conditions from the 1200-year control run simulations of HadCM3 to determine the possible causes of this severe drought. The extent and intensity of the selected SST modes are similar to those in the Pacific and Indian oceans during the 1876–1878 period from the National Oceanic and Atmospheric Administration (NOAA) Extended Reconstructed Sea Surface Temperature (ERSST) dataset. The results show that the large-scale drought of 1876–1878 is mainly driven by El Nino and a positive PDO, while the effect of IOD is not significant. El Nino may trigger the circumglobal teleconnection of the Northern Hemisphere. And, the meridional disturbance of the eastward Rossby wave train at mid-latitudes may change the intensity of the troughs and ridges and further block water vapor transport from ocean to land.

The long-term variations in meteorological drought and its large-scale climate patterns in each season in Central Asia from 1901 to 2015 remain unclear. Here, this issue is addressed using meteorology measurements and reanalysis data through correlation and composite analyses. The drought intensity index (DII) and extent index (DEI) do not exhibit significant linear trends from 1901 to 2015 but do exhibit interannual to interdecadal variations. Both the DII and DEI are highly correlated with the tropical Nino 4 sea surface temperature (SST) and extratropical atmospheric teleconnections, including the East Atlantic (EA) pattern, the East Atlantic/West Russia (EAWR) pattern, and the Arctic oscillation (AO), but with seasonal discrepancies in terms of the degree of influence. The winter drought is strongly linked to both the negative EA and negative EAWR patterns, while spring and autumn drought are strongly linked to the negative EAWR and negative EA patterns, respectively. In the winter, spring, and autumn, drought is also closely linked to below normal Nino 4 SST. The links to EA and EAWR patterns are mainly derived from their impacts on precipitation in the central and northern sectors, while the link to Nino 4 SST is mainly derived from its impacts on precipitation in the southern sector. By considering both drought intensity and drought extent, the ten extreme drought years for each season are selected and, through composite analysis, their large-scale climate patterns are studied. The extreme drought generally occurs in the contexts of a negative EA pattern in winter, a negative EAWR pattern in spring, and a negative AO pattern in autumn. As an exception, summer drought is weakly correlated with Nino 4 SST and is not correlated with extratropical atmospheric teleconnections.

Summary Species of the family Tylenchidae are encountered in large numbers in soils. The genus Labrys was recently described characterised by a remarkable lip pattern that differs from all other known Tylenchidae genera. Here we describe a curious new species, Labrys fujianensis sp. n., that morphologically fits the genus Labrys but which is genetically divergent. The phylogeny was inferred based on 18S and 28S rDNA and light and scanning electron microscopy were used to extract detailed morphologies. The phylogenetic position of this species and its phenotypic convergence are discussed. The possibility of a long-branch attraction artefact was inspected both by removal of variable nucleotide sites and monophyletic testing of topologies. The results confirmed the divergent positioning of the presented species and it is demonstrated that the genetic diversity in Tylenchidae may be much higher than expected due to morphological homoplasy.

Summary In this study, we describe Labrys fuzhouensis sp. n. based on detailed morphology revealed by scanning electron microscopy and molecular data inferred from 18S and 28S rRNA. The new species differs from other Labrys species by a combination of several morphometric and morphological characters: vulva-anus distance 66-74 μm, tail length 172-182 μm, post-uterine sac 11-12 μm, excretory duct less sclerotised, and hexagon-shaped labial disc. The novelty of L. fuzhouensis sp. n. is also confirmed by multi-dimensional scaling analysis. The 18S and 28S rRNA-based phylogenies suggest that the new species nested in the Labrys clade as sister to L. chinensis. In addition to the new species description, Coslenchus rafiqi is reported from China for the first time, the description being supplemented by the first molecular data (18S and 28S rRNA) for this species.

Tylenchidae is a widely distributed soil-inhabiting nematode family. Regardless their abundance, molecular phylogeny based on rRNA genes is problematic, and the delimitation of taxa in this group remains poorly documented and highly uncertain. Mitochondrial Cytochrome Oxidase I (COI) gene is an important barcoding gene that has been widely used species identifications and phylogenetic analyses. However, currently COI data are only available for one species in Tylenchidae. In present study, we newly obtained 27 COI sequences from 12 species and 26 sequences from rRNA genes. The results suggest that the COI gene is valid to delimitate Tylenchidae species but fails to resolve phylogenetic relationships. Tylenchidae is a widely distributed soil-inhabiting nematode family. Regardless their abundance, molecular phylogeny based on rRNA genes is problematic, and the delimitation of taxa in this group remains poorly documented and highly uncertain. Mitochondrial Cytochrome Oxidase I (COI) gene is an important barcoding gene that has been widely used species identifications and phylogenetic analyses. However, currently COI data are only available for one species in Tylenchidae. In present study, we newly obtained 27 COI sequences from 12 species and 26 sequences from rRNA genes. The results suggest that the COI gene is valid to delimitate Tylenchidae species but fails to resolve phylogenetic relationships.

The potential causes of megadroughts over North China (NC) in the preindustrial period were investigated using eight climate models evolved using CMIP5/PMIP3 and multiple proxy data. The full forcing experiments driven by both external forcing and internal variability show that megadroughts in NC were accompanied by extensive decadal drying over the Northern Hemisphere (NH), particularly in most of North America and Europe. The spatial pattern of hydroclimate matched well with the proxy-based illustration. However, such hydroclimate conditions over NH were difficult to reproduce in control experiments driven solely by internal variability. This finding suggests that external forcing may be a crucial factor leading to megadroughts in NC and simultaneous decadal drying over the NH. Moreover, external forcing may lead to climate cooling. Climate cooling weakened the pressure gradient from the West Pacific to East Asia and hence reduced the water vapor to land; meanwhile, local vertical downward movement occurred in the cooling climate background, which was unfavorable to air convection over NC. Both reduced water vapor and weakened air convection led to less precipitation. Meanwhile, there was a negative NAO, which intensified the eastward wave train at mid-latitudes. Consequently, the North American trough and European trough deepened, the northerlies in the post trough pattern intensified, and the water vapor from the high-latitude continent or polar areas was low, which was unfavorable to precipitation. This study implies that the megadrought in NC and simultaneous hydroclimatic spatial pattern over the NH may be underestimated in the CMIP5 climate prediction, which excludes external forcing.