Accretion of matter onto black holes (BHs) is a prevalent phenomenon in the cosmos, resulting in consequential changes to both the mass and irreducible mass of the BH. These alterations significantly ...impact the rotational energy reservoir harbored within. This study investigates the relationship between the increase in a BH’s irreducible mass and the augmentation of its total mass due to the infall of matter (test particles) from the innermost stable circular orbit (ISCO) of a Kerr BH. Interestingly, the ratio of total mass growth to irreducible mass growth proves to be a non-monotonic function concerning the dimensionless spin parameter. It initially rises with spin, culminating near an extreme BH (
), before declining. At the extreme BH position, the ratio is
, indicating that accretion along the ISCO leads to the ultimate stabilization of the BH as an extreme one. Conversely, massless particles falling along unstable circular orbits exhibit a continuous increasing ratio of total mass growth to irreducible mass growth with respect to the dimensionless spin parameter.
The electron-rich five-membered aromatic aza-heterocyclic imidazole, which contains two nitrogen atoms, is an important functional fragment widely present in a large number of biomolecules and ...medicinal drugs; its unique structure is beneficial to easily bind with various inorganic or organic ions and molecules through noncovalent interactions to form a variety of supramolecular complexes with broad medicinal potential, which is being paid an increasing amount of attention regarding more and more contributions to imidazole-based supramolecular complexes for possible medicinal application. This work gives systematical and comprehensive insights into medicinal research on imidazole-based supramolecular complexes, including anticancer, antibacterial, antifungal, antiparasitic, antidiabetic, antihypertensive, and anti-inflammatory aspects as well as ion receptors, imaging agents, and pathologic probes. The new trend of the foreseeable research in the near future toward imidazole-based supramolecular medicinal chemistry is also prospected. It is hoped that this work provides beneficial help for the rational design of imidazole-based drug molecules and supramolecular medicinal agents and more effective diagnostic agents and pathological probes.
Background
To conduct a meta‐analysis to compare the safety and efficacy of transoral endoscopic thyroidectomy vestibular approach (TOETVA) with conventional open thyroidectomy (COT).
Methods
...MEDLINE, EMBASE, Science Citation Index Expanded, and the Cochrane Central Register of Controlled Trials in the Cochrane Library from January 2007 to March 2020 were searched to identify studies comparing TOETVA and COT.
Results
Six eligible nonrandomized studies involving 1151 patients were included. Meta‐analysis results revealed that TOETVA group had a significantly longer operative time (weighted mean difference WMD, 66.09; 95% confidence interval CI, 35.22‐96.96; P < .0001) and larger amount of drainage (WMD, 98; 95% CI, 20.14‐175.86; P = .01). There were no significant differences in terms of postoperative outcomes.
Conclusion
TOETVA appears to be as feasible and safe as the COT for the treatment of patients with benign thyroid nodules and selected differential thyroid carcinomas.
Water scarcity mitigation in regional agricultural systems contributes to water use efficiency improvement. Blue (WSI
blue
), green (WSI
green
) and grey (WSI
grey
) water scarcity indices were ...proposed to describe various water stresses in detail and further determine the type of regional water scarcity. WSI
blue
and WSI
green
reveal resource-based water scarcities, and WSI
grey
characterizes environment-based water shortages. Provincial water scarcity indices of China from 2000–2014 were calculated and analyzed in the current paper. The results indicated that the national WSI, WSI
grey
, WSI
blue
and WSI
green
values are 0.84, 0.16, 0.39 and 0.89, respectively. China is facing a high water stress, manifested as a resource-based water shortage. Northwest and Northeast China experience a severe water quantity scarcity with high WSI
blue
and WSI
green
values, and the central and eastern regions exhibit a high WSI
grey
value. Eastern China faces both serious resource-based and environmental water shortages. The constructed blue, green and grey water scarcity indices compensate for the inability of the existing index to determine the type of water shortage and indicate the reason for water scarcity. They also provide a targeted guiding significance for the formulation of effective measures to improve agricultural water resource management and alleviate regional water scarcity.
Differently-treated crops straw is being widely used to fertilize soil, while the potential impacts of straw amendment on the biogeochemistry and phytoavailability of mercury in contaminated soils ...are largely unknown. In the present study, differently-treated rice straw (dry straw, composted straw, straw biochar, and straw ash) was incorporated into mercury-contaminated soil at an environment relevant level (1/100, w/w), and mercury speciation, methylmercury (MeHg) phytoavailability (using ammonium thiosulfate extraction method, validated elsewhere) and bioaccumulation (in Indian mustard Brassica junceas) were quantified. Our results indicated that incorporating straw biochar or composted straw into soil would decrease phytoavailable MeHg levels, possibly due to the strong binding of MeHg with particulate organic matter in amended straw (‘MeHg immobilization effect’). Consequently, MeHg accumulation in aboveground tissue of Indian mustard harvested from straw biochar-amended soil decreased by 20% compared to the control. Differently, incorporation of dry straw resulted in elevated MeHg levels in soil (‘Mercury methylation effect’). Decomposition of amended dry straw in soil would evidently increase DOC levels (averagely 40%–195% higher than the control), which may subsequently mobilize MeHg in the soil (‘MeHg mobilization effect’). Accordingly, incorporation of dry straw led to increased phytoavailable MeHg levels in the soil and doubled MeHg accumulation in Indian mustard. Our results provided the first evidence that incorporating differently-treated rice straw into soil could have diverse effects on mercury biogeochemistry and phytoavailability, which should be taken into account in risk assessment or soil remediation.
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•Incorporating differently-treated straw had diverse effects on MeHg biogeochemistry.•Incorporation of dry straw into soil increased phytoavailable MeHg levels.•Incorporation of dry straw could affect both soil MeHg levels and MeHg phytoavailability.•Straw decomposition in soil produced high levels of DOM, which may mobilize MeHg.•Incorporation of straw biochar or composted straw reduced phytoavailable MeHg.
•Water footprint was measured along with water and fertilizer utilization processes on farmland.•Grey water footprint was the major part of water footprint of paddy rice.•Changes of precipitation did ...not affect total water footprint, but changed its composition and made production more clean.
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Water footprint (WF) is a comprehensive measure of water consumption by human activities and can be used to assess the impact on both water volume and quality. This study aims to explore the feasibility of evaluating green, blue and grey WFs of crop production based on field measurements. The irrigated paddy rice grown in three different experimental sites in different typical irrigation districts in Huai'an, East China over 2011 to 2014 was taken as study case. With fixed irrigation and fertilization, on the basis of measuring field water and fertilizer balance at daily step, we calculated WF of crop production under different test treatments. Results show that crop water requirement of rice was measured as 667.1mm and 6.2% of the total nitrogen (T-N) was washed away from farmland accompany with drainage and percolation. Average annual WF of paddy rice during 2011–2014 in Huai'an was 1.760m3/kg (33.3% green, 25.8% blue and 40.9% grey). The level of WF and blue water proportion in different locations (irrigation districts) and different years changed slightly, while the proportion of green and grey WF changed with the variance of precipitation. Green water proportion was 25.1%, 34.2 and 44.2%, while 48.0%, 40.2% and 31.0% for grey water proportion under precipitation levels of 400, 600 and 800mm, respectively. The reduced grey WF was due to increased drainage. This study not only proved the feasibility of assessing WF of crop production with field experiments, but also provided a new method for WF calculation based on field water and fertilizer migration processes.
Phelan-McDermid syndrome (PMDS) is a complex neurodevelopmental disorder characterized by global developmental delay, severely impaired speech, intellectual disability, and an increased risk of ...autism spectrum disorders (ASDs). PMDS is caused by heterozygous deletions of chromosome 22q13.3. Among the genes in the deleted region is SHANK3, which encodes a protein in the postsynaptic density (PSD). Rare mutations in SHANK3 have been associated with idiopathic ASDs, non-syndromic intellectual disability, and schizophrenia. Although SHANK3 is considered to be the most likely candidate gene for the neurological abnormalities in PMDS patients, the cellular and molecular phenotypes associated with this syndrome in human neurons are unknown. We generated induced pluripotent stem (iPS) cells from individuals with PMDS and autism and used them to produce functional neurons. We show that PMDS neurons have reduced SHANK3 expression and major defects in excitatory, but not inhibitory, synaptic transmission. Excitatory synaptic transmission in PMDS neurons can be corrected by restoring SHANK3 expression or by treating neurons with insulin-like growth factor 1 (IGF1). IGF1 treatment promotes formation of mature excitatory synapses that lack SHANK3 but contain PSD95 and N-methyl-D-aspartate (NMDA) receptors with fast deactivation kinetics. Our findings provide direct evidence for a disruption in the ratio of cellular excitation and inhibition in PMDS neurons, and point to a molecular pathway that can be recruited to restore it.
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