Crystal structure, thermal analyses, and acetate binding properties in Zinc(II) complex of a urea-functionalized pyridyl ligand

1302-1310A zinc(II) acetate complex with a urea-functionalized pyridyl ligand, [ZnL2(OAc)2]·2H2O (1) (L = N-(4-chlorophenyl)-N'-(4-pyridyl)urea), has been synthesized by the reaction of L with Zn(OAc)2·2H2O under water-containing condition. X-ray single-crystal diffraction analyses reveal that 2-D sheetlike network structure has been formed by the urea N−H×××Npyridyl interactions and C–H···O interactions in the free ligand L. Complex 1 features 3-D hydrogen bonded network formed by intermolecular N−H···O hydrogen bonds and O−H×××O hydrogen bonds involving urea groups, acetate anions and bridged water molecules. The hydrogen bonds play an important role in stabilizing the supramolecular structures. Thermal gravity analyses have been used to investigate the thermal stabilities of L and 1, and the apparent activation energy (Ea) of the decompositions have also been calculated, and the results indicate that the main decomposition of L needs higher apparent activation energy values Ea than that of 1. The acetate binding properties of L in solution have also been evaluated by Ultraviolet-Visible (UV-Vis) spectroscopy. CCDC: 1506202, L; 1506203, 1

Finishing the euchromatic sequence of the human genome

The sequence of the human genome encodes the genetic instructions for human physiology, as well as rich information about human evolution. In 2001, the International Human Genome Sequencing Consortium reported a draft sequence of the euchromatic portion of the human genome. Since then, the international collaboration has worked to convert this draft into a genome sequence with high accuracy and nearly complete coverage. Here, we report the result of this finishing process. The current genome sequence (Build 35) contains 2.85 billion nucleotides interrupted by only 341 gaps. It covers ∼99% of the euchromatic genome and is accurate to an error rate of ∼1 event per 100,000 bases. Many of the remaining euchromatic gaps are associated with segmental duplications and will require focused work with new methods. The near-complete sequence, the first for a vertebrate, greatly improves the precision of biological analyses of the human genome including studies of gene number, birth and death. Notably, the human enome seems to encode only 20,000-25,000 protein-coding genes. The genome sequence reported here should serve as a firm foundation for biomedical research in the decades ahead

Arginine methylation in the E2F1 pathway

The E2F1 pathway plays an important role in coordinating early cell cycle progression. Deregulation of the E2F1 pathway, which may be brought about by somatic mutations in genes such as INK4A, RB1 and CDK4, is found in a majority of cancers. The transcription factor E2F1 is able to activate genes involved in proliferation as well as apoptosis, but the mechanisms that govern these opposing biological effects remain poorly understood. In this study, I would describe how E2F1 activity can be regulated by two novel post-translational modifications which result in different functional consequences. It was found that PRMT1 asymmetrically methylates E2F1 at R109, while PRMT5 symmetrically methylates R111 and R113. The symmetric dimethyl marks on E2F1 promoted the recruitment of Skp2, a component of the E3 ubiquitin ligase complex, which coincided with decreased protein stability and transcriptional activity, as well as enhanced cell proliferation and reduced apoptosis. The asymmetric dimethyl marks on E2F1 was found to hinder symmetric dimethylation, leading to reduced cell proliferation and enhanced apoptosis. The competition between PRMT1 and PRMT5 at the E2F1 RG-rich motif was found to be regulated by the adjacent cyclin A binding site. Induction of DNA damage, which resulted in decreased cyclin A level, corresponded to an increase in PRMT1 and decrease in PRMT5 binding. This study uncovers a new mechanism in E2F1 regulation and establishes the importance of arginine methylation in cell proliferation and apoptosis.</p

Advances on Frequency Diverse Array Radar and Its Applications

Unlike the conventional phased array that provides only angle-dependent transmit beampattern, Frequency Diverse Array (FDA) employs a small frequency increment across its array elements to produce automatic beam scanning without requiring phase shifters or mechanical steering. FDA can produce both rangedependent and time-variant transmit beampatterns, which overcomes the disadvantages of conventional phased arrays that produce only angle-dependent beampattern. Thus, FDA has many promising applications. Based on a previous study conducted by the author, “Frequency Diverse Array Radar: Concept, Principle and Application” (Journal of Electronics & Information Technology, 2016, 38(4): 1000–1011), the current study introduces basic FDA radar concepts, principles, and application characteristics and reviews recent advances on FDA radar and its applications. In addition, several new promising applications of FDA technology are discussed, such as radar electronic warfare and radar-communications, as well as open technical challenges such as beampattern variance, effective receiver design, adaptive signal detection and estimation, and the implementation of practical FDA radar demos

Numerical Simulation of Gas-Liquid Flow in a Bubble Column by Intermittent Aeration in Newtonian Liquid/Non-Newtonian Liquid

The dynamic behaviors of gas-liquid two-phase flow were simulated in a lab-scale intermittent bubble column by Euler-Euler two-fluid model coupled with the PBM (population balance model) using two different liquid phases, i.e., Newtonian fluid (water)/non-Newtonian fluid (activated sludge). When non-Newtonian fluid was used during intermittent aeration, some interesting results were obtained. Two symmetric vortexes existed in the time-averaged flow field; the vertical time-averaged velocity of the liquid phase decreased with increasing anaerobic time; the average gas holdup distribution was like a trapezoid with long upper side and short lower side and affected by the dynamic viscosity of the liquid phase. Compared with non-Newtonian fluid, the use of Newtonian fluid as the liquid phase led to a more complicated time-averaged flow field structure and vertical time-averaged velocity distribution, higher average gas holdup, and the asymmetric column-shaped gas holdup distribution with increasing anaerobic time. For different liquid phases, the instantaneous flow field, instantaneous vertical velocity, and instantaneous gas holdup distribution all periodically changed with anaerobic time; however, different from Newtonian liquid phase, non-Newtonian liquid phase had no periodic oscillating instantaneous horizontal velocity

Deficit drip irrigation improves kiwifruit quality and water productivity under rain-shelter cultivation in the humid area of South China

Comprehending crop responses to water deficit at different growth stages is crucial for developing effective irrigation strategies. Different water deficit treatments (WDTs) were applied to the kiwifruit vines to investigate the effect of water deficit during different growth stages on the fruit quality, yield, and water productivity (WP); subsequently, the technique for order preference by similarity to an ideal solution method (TOPSIS) was employed to determine optimal treatments for kiwifruit cultivation. A total of 17 irrigation treatments were applied, including one control treatment (CTL, full irrigation) and four WDTs (denoted as D15%, D25%, D35%, and D45% respectively) during the bud burst to leafing (I), flowering to fruit set (II), fruit expansion (III), and fruit maturation (IV) stages. Results showed that WDTs during I, II, III, and IV decreased evapotranspiration (ET) over the whole growth period of kiwifruit vines by 1.2–3.8, 1.5–4.4, 4.7–14.3, and 6.9–21.3% compared with CTL, respectively. WDTs during stages I and II increased fruit volume (Vf) and fruit weight (FW), while exhibiting no significant impact on yield, WP, and chemical quality of kiwifruit. WDTs during stage III improved fruit firmness (Fn), total soluble solids (TSS), and titratable acidity (TA); however, it also caused severe reduction in Vf, FW, yield, and WP. Appropriate WDTs during stage IV significantly improved Fn, TSS, TA, vitamin C (Vc), and WP without compromising Vf, FW, and yield of kiwifruit. The IV-D25% treatment was determined to be the optimal treatment for improving fruit quality and WP of kiwifruit while maintaining yield, which increased TSS, TA, Vc, and WP by 9.1, 6.1, 19.2, 4.6%, respectively; the combination of D25%, D25%, full irrigation, and D25% treatments during stages I, II, III, and IV should be a viable irrigation strategy to simultaneously achieve high yield, quality, and WP of kiwifruit