Oxytocinergic neurons, but not oxytocin, are crucial for male penile erection.

The cumulative evidence suggests that oxytocin is involved in the male sexual behaviors. However, no significant sexual impairments were observed in oxytocin gene knock-out (KO) mice, suggesting that oxytocin is not necessary for sexual behavior in male mice. To better understand the role of oxytocin in male erection, two types of oxytocin gene KO mice were created. In the first type, the oxytocin gene was deleted in the zygote, while in the second type, the oxytocin gene was mutated in adulthood by injecting the CRISPR/Cas9 AAVs. The results showed that disrupting the oxytocin gene at either the embryonic or adult stage did not affect erection, indicating that oxytocin is not necessary for penile erection. Pharmacologically, injecting oxytocin receptor agonist Carbetocin into the VTA of the oxytocin gene KO mice still evoked penile erection. By employing the Oxt-Ires-Cre mice, we found that specifically activating oxytocinergic neurons through chemogenetics strongly induced penile erection, while inhibiting these neurons blocked the erection responses. Furthermore, ablating PVN oxytocinergic neurons abolished the male erection response. In conclusion, although the neuropeptide oxytocin is not essential for male erection, the activity of oxytocinergic neurons is required. Our results might reflect the redundancy in the central nerve system in the sense that many signals contribute to the activation of oxytocinergic neurons to evoke penile erection during sexual behaviors.

[Arsenic Methylation Efficiency Changes During Paddy Soil Drying and Its Key Influencing Factors Analysis].

The straight head disease of rice is one of the main problems limiting rice production. Arsenic (As) methylation in paddy soils is considered to be highly related to the occurrence of the straight head disease. As a typical field practice, rice fields are usually drained during the late tillering stage and the mid-late grain filling stage. Nevertheless, the key influencing factors on the As methylation efficiency during paddy soil drying remain unclear. In this study, an indoor cultivation experiment was set up to simulate the drying process of paddy soil. Two As-contaminated soils collected from Xingren (XR) in Guizhou province and Nandan (ND) in Guangxi province were used as test soils. Each soil was treated with the addition of rice straw (RS) and without rice straw (CK). With the drying of paddy soil (0, 24, 36, 48, and 60 h), the changes in soil Eh, pH, total organic carbon (TOC), and As chemical species in the porewater were determined. The abundance of the As methylation functional gene (arsM), sulfate-reducing bacteria (harboring dsrA, As methylation-related microorganism), and methanogens (harboring mcrA, As demethylation-related microorganism), as well as the diversity of arsM-harboring microorganisms, were also observed. The results showed that during the process of drying paddy soil, soil Eh changed from -300--200 mV under complete flooding to -150--50 mV after drying; however, the change in soil pH was not obvious. The concentrations of inorganic As (iAs) and dimethylarsenic (DMAs) in porewater significantly increased (P<0.05) with the drying process. Additionally, the concentration of DMAs in the RS treatment was prominently higher than that in CK. Compared with XR soil, the concentration of DMAs in ND soil was higher. As a function of soil drying time, the As methylation efficiency of XR soil (XR-CK and XR-RS) slightly increased but was not significant (P>0.05), whereas the As methylation efficiency of ND soil (ND-CK and ND-RS) increased significantly (P<0.05). After the drying time reached 60 h, the As methylation efficiency of ND-CK and ND-RS increased by 61.8% and 23.2%, respectively, compared with those at the early stage of drying (0 hours). The copy numbers of the arsM and dsrA genes greatly increased with the extension of drying time, whereas an opposite trend was observed for the copy number of the mcrA gene. Furthermore, the addition of straw obviously increased the gene abundance of whole bacteria and arsM-, dsrA-, and mcrA-harboring bacteria. Based on the multi-factor analysis of variance and the redundancy analysis, it was found that the test soil type, straw addition, drying time, and their interaction had a critical influence on the changes in As species, As methylation efficiency, and the gene abundance in soils. TOC, Eh, and the functional genes associated with As methylation were positively linked with the methylated As content in soil porewater but negatively correlated with that of iAs. According to the sequence of the arsM-harboring microbe, it was clearly demonstrated that a community shift of As-methylating microbe occurred with the soil drying. Here, the following conclusions were derived:① the drying process did not lower the As methylation efficiency in paddy soil. On the contrary, in this study, the As methylation efficiency, especially that for ND soil, remarkably improved. The addition of straw notably promoted the As methylation efficiency and the content of DMAs in porewater. ② An increasing tendency was observed for the abundance of microbes related to As methylation, whereas a reverse trend was indicated for microbes related to As demethylation. The community shift of arsM-harboring microbes might be the crucial reason for the improved As methylation efficiency during the soil drying. These observations contribute to a better understanding of the As methylation process during paddy soil drying and will shed light on the future mitigation of rice straight head disease in paddy soils.

CBCT Evaluation of Buccolingual Orientation of Inferior Alveolar Canal in Mandibular Posterior Region for Implant Planning.

Purpose: Inferior alveolar nerve (IAN) can be subjected to iatrogenic injury during implant surgical procedures. The purpose of this retrospective study was to identify the buccolingual orientation of IAN in posterior mandible as adjunct information for implant planning and to estimate ethnicity-, sex-, and side-related variations in Malaysian population. Material and Methods. A total of 121 CBCT images were viewed with eXamVision software. The buccolingual position of IAN was identified in the posterior region. Buccal bone width (B), canal thickness (C), and lingual bone width (L) were measured at the horizontal canal levels. Kruskal-Wallis H test and Friedman test were used to analyze the buccolingual position. One-way ANOVA was performed to evaluate the variations in B, C, and L values. Results: Overall, most of the IANs were located on the lingual sides of the second molar regions (left: 71.9%; right: 71.1%) and at the centers of the first molar regions (left: 57.9%; right: 47.10%) and exited through the mental foramen before the second premolar regions. There was statistically significant difference in the buccolingual position of the IAN between the sexes in the left second premolar regions (P = 0.03). There was variation in B between the sexes in the left first molar regions (P = 0.01). Statistically significant differences in C and L were also found between different ethnic groups (P = 0.04). Between both sides, there were variations in C in the first molar regions (P < 0.001) and the second molar regions (P = 0.03). Conclusion: From the second molar to the second premolar, the buccal bone width decreased while the lingual bone width increased. There were variations between ethnicities, sexes, and sides among Malaysians.

Thermodynamics, Kinetics, and Mechanisms of the Co-Removal of Arsenate and Arsenite by Sepiolite-Supported Nanoscale Zero-Valent Iron in Aqueous Solution.

In this study, a newly synthesized sepiolite-supported nanoscale zero-valent iron (S-nZVI) adsorbent was tested for the efficient removal of As(III) and As(V) in aqueous solution. Compared with ZVI nanoparticles, the As(III) and As(V) adsorption abilities of S-nZVI were substantially enhanced to 165.86 mg/g and 95.76 mg/g, respectively, owing to the good dispersion of nZVI on sepiolite. The results showed that the adsorption kinetics were well fitted with the pseudo-second-order model, and the adsorption isotherms were fitted with the Freundlich model, denoting a multilayer chemical adsorption process. The increase in the initial solution pH of the solution inhibited As(III) and As(V) adsorption, but a weaker influence on As(III) than As(V) adsorption was observed with increasing pH. Additionally, the presence of SO42- and NO3- ions had no pronounced effect on As(III) and As(V) removal, while PO43- and humic acid (HA) significantly restrained the As(III) and As(V) adsorption ability, and Mg2+/Ca2+ promoted the As(V) adsorption efficiency. Spectral analysis showed that As(III) and As(V) formed inner-sphere complexes on S-nZVI. As(III) oxidation and As(V) reduction occurred with the adsorption process on S-nZVI. Overall, the study demonstrated a potential adsorbent, S-nZVI, for the efficient removal of As(III) and As(V) from contaminated water.

The performance and mechanism of cadmium availability mitigation by biochars differ among soils with different pH: Hints for the reasonable choice of passivators.

The performances of passivation materials mitigating Cadmium (Cd) bioavailability considerably vary with the pH condition of Cd-contaminated soils. However, less information was available for the method of improving Cd passivation efficiency taking into account the pH of the targeted soil. Furthermore, the underlying mechanism of Cd availability mitigation in soils with different pH has not been clearly explored. In this study, cotton straw biochar (CSB) and its modified products using NaOH (CSB-NaOH) were prepared and applied in two kinds of Cd-contaminated soils with different pH. It was found that CSB-NaOH was more effective than CSB in regulating the Cd bioavailability in the acid soil, while the opposite tendency was observed in alkaline soil. The difference of the Cd passivation efficiency is correlated with contributions of various Cd-biochar binding mechanisms, which cation exchange mechanism is largely eliminated for CSB-NaOH. The interaction of Cd with CSB/CSB-NaOH was further evidenced through characterization results of Scan Electron Microscopy (SEM), X-Ray Diffraction (XRD), Fourier-transformed infrared spectroscopy (FTIR) and X-ray Photoelectron spectroscopy (XPS). Characterization results proved that carboxyl, hydroxyl and ethyl groups were the key functional groups involved in Cd passivation. XPS results showed that Cd binding methods varied between CSB and CSB-NaOH, which Cd2+ and Cd-O were the main form of Cd binding to CSB while Cd-O was the main form on CSB-NaOH. In this work, it was demonstrated that in acid soil, pH change caused by biochar plays a more significant role in controlling the Cd bioavailability, while in alkaline soil, the strength of the Cd-biochar interaction is more decisive for the Cd passivation efficiency. This work provides information on how to select the suitable passivator to decrease the Cd bioavailability in terms of different soil pH and property.

Exogenous fulvic acid enhances stability of mineral-associated soil organic matter better than manure.

Mineral-associated soil organic matter (MAOM) is seen as the key to soil carbon sequestration, but its stability often varies with types of exogenous organic materials. Fulvic acid and manure are ones of the exogenous organic materials used for the improvement of degraded soil. However, little is known about if and how fulvic acid and manure affect the stability of MAOM. Using a field experiment of four fertilization treatments (no fertilization, mineral fertilizers, fulvic acid, and manure) and a comprehensive meta-analysis using relevant studies published prior to January 2020, we investigated effects of exogenous fulvic acid and manure applications on four MAOM stability indexes: association intensity, humus stabilization index, iron oxide complex coefficient, and aluminum oxide complex coefficient. Exogenous fulvic acid and manure applications increased soil organic carbon fractions by 26.04-48.47%, MAOM stability by 12.26-387.41%, and complexed iron/aluminum contents by 16.12-20.01%. Fulvic acid application increased MAOM stability by promoting mineral oxide complexation by 20.33% and manure application improved MAOM stability via increasing humus stabilization by 21-25%. Association intensity was positively correlated with contents of soil carbon fractions and the metal oxide complex coefficients were positively correlated with iron/aluminum oxide contents. Moreover, stable-humus exerted significantly positive direct and indirect effects on association intensity and humus stabilization index, while amorphous iron/aluminum content had significantly negative influences on metal oxide complex coefficients. The meta-analysis verified that long-term fulvic acid application improved MAOM stability more so than manure application in acidic soils. We recommend that strategies aiming to prevent land degradation should focus on the potential of fulvic acid as a soil amendment because it can significantly increase MAOM stability.

[Spatial-temporal differentiation of mountain-water-forest-farmland-lake-grass system in Qinghai area of the Qilian Mountain National Park, China]. / ç¥è¿žå±±å›½å®¶å ¬å›­é’æµ·ç‰‡åŒºå±±æ°´æž—ç”°æ¹–è‰çš„æ—¶ç©ºåˆ†å¼‚.

Higher and more precise requirements are critically needed for the protection, regulation, and restoration of ecological environment in the Qilian Mountain National Park after it is classified as a national park system pilot in China. Based on remote sensing data in 1980-2018, the spatial pattern map of mountain-water-forest-farmland-lake-grass system was constructed to analyze its spatial-temporal variations in the general control area and core conservation area in Qinghai area of the Qilian Mountain National Park. The results showed that grasslands, with an area of 8174.93 km2, were the main landscape in the park, and that grassland area in the core conservation area was 1.2 times as that of the general control area. The bare exposed rocks, a major type of unused land, accounted for 86.7% and 79.4% of the unused land in the core conservation area and the general control area, respectively. Forest area in the general control area was larger than that in the core conservation area. Water area in the core conservation area was 4.9 times as large as that in the general control area, with 90.4% of which being dominated by permanent glaciers and snowfields. The drylands were mainly concentrated in the general control area. From 1980 to 2018, the water area was decreasing and had been reduced by 186.75 km2. The area of permanent glaciers and snowfields decreased the most, with a drop of 12.05 and 175.88 km2 in the general control area and the core conservation area, respectively. The area of forests and grasslands were enlarged constantly. The changes of high-, medium-, and low-coverage grasslands in the core conservation area were greater than that in the general control area, which were the most significant during 1990-2000. Moreover, the degradation of high- and medium-coverage grasslands in the general control area as well as high- and low-coverage grasslands in the core conservation area was observed from 1980 to 2018. The area of bare exposed rocks was on the rise, while the permanent glaciers and snowfields displayed a decreasing trend. The permanent glaciers and snowfields and the bare exposed rocks exhibited the most obvious changes in the park. The glaciers in the core conservation area retreated remarkably faster than those in the general control area, which were transformed into the bare exposed rocks mainly in 1980-1990 and 2000-2010.

[Effects of different organic amendments on soil organic carbon and its labile fractions in the paddy soil of a double rice cropping system]. / æœ‰æœºç‰©æ–™è¿˜ç”°å¯¹åŒå­£ç¨»ç”°åœŸå£¤æœ‰æœºç¢³åŠå ¶æ´»æ€§ç»„åˆ†çš„å½±å“.

Application of organic amendments is an effective approach for improving soil organic carbon and soil fertility. To investigate the effects of different organic amendments on soil organic carbon and its labile fraction content, a batch of incubation experiments was conducted on the fluvo-aquic soil in Dongting Lake region, Hunan Province. There were six treatments, including soil amended with rice straw, soil amended with Chinese milk vetch, soil amended with bio-organic fertilizer, soil amended with pig manure, and soil amended with rice straw-derived biochar, with unamended soil as control. Each treatment had the same amount of carbon input. After 180 days of incubation, application of organic amendments increased soil labile organic carbon content. Application of bio-organic fertilizer, pig manure and rice straw-derived biochar significantly increased soil organic carbon content by 26.1%, 9.7% and 30.7%, respectively. There was no significant change in soil organic carbon content in rice straw and Chinese milk vetch treatments which were more favourable to the accumulation of soil dissolved organic carbon and microbial biomass carbon. Pig manure was more favourable to the accumulation of soil dissolved organic carbon. Bio-organic fertili-zer could benefit the accumulation of soil microbial biomass carbon and readily oxidizable organic carbon. Rice straw-derived biochar could promote the accumulation of soil microbial biomass carbon and light fraction organic carbon. Compared with rice straw, soil carbon pool management index was increased by 31.8%, 111.6%, 62.2% and 50.7% in Chinese milk vetch, bio-organic fertilizer, pig manure and rice straw-derived biochar treatments, respectively. The performance of bio-organic fertilizer, pig manure, and rice straw biochar was better than rice straw and Chinese milk vetch from the perspective of soil carbon sequestration and soil carbon pool management index.

[Changes of growing season NDVI at different elevations, slopes, slope aspects and its relationship with meteorological factors in the southern slope of the Qilian Mountains, China from 1998 to 2017]. / 1998­2017年祁连山南坡不同海拔、坡度和坡向生长季NDVIå˜åŒ–åŠå ¶ä¸Žæ°”è±¡å› å­çš„å ³ç³».

Qilian Mountains is an important water conservation area in Northwest China, which is the boundary between the first and second steps of China's topography and is sensitive to climate change. Based on the data of temperature, precipitation, normal difference vegetation index (NDVI), and digital elevation model (DEM) data, we analyzed NDVI change and its relationship with temperature and precipitation along the elevation, slope and slope aspect in the southern slope of Qilian Mountains using tendency analysis method, wavelet analysis and correlation analysis. The results showed that, from 1998 to 2017, NDVI value of the growing season presented increasing trend by a rate of 0.023·10 a-1. Changes of NDVI differed at different elevations, slopes and slope aspects. NDVI increased first and then decreased with elevation. The vegetation coverage at 2700-3700 m was good, and degraded in the area of >4700 m. NDVI reduced with the increases of slope, which showed little difference in different slope aspects but was better in sunny slope than in shade slope. NDVI of the growing season was closely related with temperature and precipitation. NDVI, temperature and precipitation in growing season all had a 14-year cycle. Vegetation at different elevations, slopes and slope aspects was differently affected by temperature and precipitation. Vegetation in areas with altitude <3700 m, >4700 m, slope <25° and each slope direction was more sensitive to precipitation.

[Land use change and its driving force on the southern slope of Qilian Mountains from 1980 to 2018]. / 1980­2018å¹´ç¥è¿žå±±å—å¡åœŸåœ°åˆ©ç”¨å˜åŒ–åŠå ¶é©±åŠ¨åŠ›.

Qilian Mountains is the boundary of the first and second steps of China's terrain, with fragile ecological environment. There is great ecological significance to study land use change and driving force in transitional areas. In this study, we investigated the spatial and temporal characte-ristic of land use and its driving force in the south slope of Qilian Mountains, based on RS image data from 1980 to 2018, with the spatial autocorrelation method, ArcGIS spatial analysis method and principal component analysis. The results showed that, from 1980 to 2018, grassland was the main land use type, and the proportion of construction land was the smallest. Water area and grassland showed a declining trend, while unused land, construction land and farmland showed an increasing trend. There was smaller change for the woodland. The single dynamic degree of different land types decreased following an order of construction land, water, farmland, unused land, woodland and grassland. The comprehensive dynamic degree of land use was 0.9%. The spatial distribution of different land use types showed the characteristics of spatial agglomeration. The increased areas of farmland and the decreased areas of woodland and grassland were mainly distributed in the northwest of the Datong River valley of Menyuan County, while in the upper reaches of Datong River in the northeast of Tianjun County, grassland was occupied by construction land. The driving force of land use was population, science and technology, urbanization, level of economic development, and policies. Our results would support the government to reasonably plan and utilize land resources, which is of significance to the protection of ecological environment and the sustainable development of society and economy on the southern slope of Qilian Mountains.

Mutation at Different Sites of Metal Transporter Gene OsNramp5 Affects Cd Accumulation and Related Agronomic Traits in Rice (Oryza sativa L.).

OsNramp5 is a key gene involved in the control of the uptake of Cd, Mn, and other metal ions by rice root cells. The functional deficiency of this gene can significantly reduce the accumulation of Cd in rice grains, but the effects of its mutation on agronomic traits such as yield and quality have not been investigated comprehensively yet. In the present study, three Huanghuazhan-based OsNramp5 mutants [LCH1 (Low Cadmium Huanghuazhan 1), LCH2 (Low Cadmium Huanghuazhan 2), and LCH3 (Low Cadmium Huanghuazhan 3)] were obtained using clustered regularly interspaced short palindromic repeats/CRISPR-associated protein 9 (CRISPR/Cas9) technology. The mutation-type analysis showed that LCH1, LCH2, and LCH3 encoded defective OsNramp5 protein sequences containing only 76aa, 176aa, and 266aa, respectively. The determination of metal content and the statistics of related agronomic traits revealed that the functionally deficient OsNramp5 not only significantly reduced the accumulation of Cd in the grains of the mutants but also affected rice yield and quality. However, with the decrease of OsNramp5 mutation degree, its effects on chlorenchyma Mn accumulation, yield, and quality were also diminished. Additionally, we also found that the increase in the concentration of Mn in the soil restored the phenotype of the declined yield and quality due to the functional deficiency of OsNramp5. Our findings provide novel insights into and new materials for breeding rice varieties with low Cd accumulation and excellent agronomic traits under severe Cd pollution environment.

The Secreted Protein MoHrip1 Is Necessary for the Virulence of Magnaporthe oryzae.

Secreted effectors from Magnaporthe oryzae play critical roles in the interaction with rice to facilitate fungal infection and disease development. M. oryzae-secreted protein MoHrip1 can improve plant defense as an elicitor in vitro, however, its biological function in fungal infection is not clear. In this study, we found that the expression of mohrip1 was significantly induced in the stages of fungal penetration and colonization. Although dispensable for the growth and conidiation, MoHrip1 was necessary for the full virulence of M. oryzae. Deletion of mohrip1 remarkably compromised fungal virulence on rice seedlings and even on rice leaves with wounds. Rice sheath inoculation assay further demonstrated the defects of mohrip1-deleted mutants on penetration and proliferation in rice cells. Additionally, compared with WT and complementation strain, the inoculation of mohrip1-deleted mutants induced a higher expression of specific defense related genes and a higher production of specific defensive compounds in rice leaves. These data collectively indicated that MoHrip1 is necessary for fungal penetration and invasive expansion, and further full virulence of rice blast fungus.

Versatile mesoporous DyIII coordination framework for highly efficient trapping of diverse pollutants.

This work presents a mesoporous Dy(III) metal-organic framework with two types of void cages (diameters: 4.4 and 2.8 nm), which can efficiently adsorb a variety of chemical pollutants, including toxic metals, iodine, and formaldehyde.