The functions of Sertoli cells in spermatogenesis have attracted much more attention recently. Normal spermatogenesis depends on Sertoli cells, mainly due to their influence on nutrient supply, ...maintenance of cell junctions, and support for germ cells' mitosis and meiosis. Accumulating evidence in the past decade has highlighted the dominant functions of the MAPK, AMPK, and TGF-β/Smad signaling pathways during spermatogenesis. Among these pathways, the MAPK signaling pathway regulates dynamics of tight junctions and adherens junctions, proliferation and meiosis of germ cells, proliferation and lactate production of Sertoli cells; the AMPK and the TGF-β/Smad signaling pathways both affect dynamics of tight junctions and adherens junctions, as well as the proliferation of Sertoli cells. The AMPK signaling pathway also regulates lactate supply. These signaling pathways combine to form a complex regulatory network for spermatogenesis. In testicular tumors or infertile patients, the activities of these signaling pathways in Sertoli cells are abnormal. Clarifying the mechanisms of signaling pathways in Sertoli cells on spermatogenesis provides new insights into the physiological functions of Sertoli cells in male reproduction, and also serves as a pre-requisite to identify potential therapeutic targets in abnormal spermatogenesis including testicular tumor and male infertility.
Information processing with optoelectronic devices provides an alternative way to efficiently process hybrid optical and electronic signals. Ferroelectric field‐effect transistors (FeFETs) can ...effectively respond to external optical and electrical stimuli by modulating their polarization states. Here, a 2D FeFET is demonstrated by the epitaxial growth of high‐quality 2D bismuth layered oxyselenide (Bi2O2Se) films on PMN‐PT(001) ferroelectric single‐crystal substrates. Upon switching the polarization direction of PMN‐PT, the authors realize in situ, reversible, and nonvolatile manipulation of the resistance of Bi2O2Se thin film (≈877%). The device simultaneously exhibits a polarization‐dependent photoresponse through visible light (λ = 405 nm) and infrared light (IR, λ = 980 nm) illumination. Combining optical stimuli with ferroelectric gating, it is demonstrated that the devices not only show nonvolatile memory and optoelectronic responses, but also show coincidence detection of visible and IR light. This work holds great potential in constructing new multiresponse and multifunction 2D‐FeFETs.
2D ferroelectric field‐effect transistors devices are fabricated by epitaxial growth of Bi2O2Se on Pb(Mg1/3Nb2/3)O3‐PbTiO3. The devices exhibit ferroelectric polarization‐dependent photoresponse upon visible light (λ = 405 nm) and infrared light (IR, λ = 980 nm) illumination. Combining optical stimuli with ferroelectric gating, the devices show not only nonvolatile memory and optoelectronic response, but also coincidence detection of visible and infrared light.
The functional sperm is the key factor for species continuation. The process spermatogenesis, to produce mature sperm is quite complex. It begins with the proliferation and differentiation of ...spermatogonia, which develop from primary spermatocytes to secondary spermatocytes and round spermatids, which eventually develop into fertile mature sperm. Spermiogenesis is the latest stage of spermatogenesis, where the round spermatids undergo a series of dramatic morphological changes and extreme condensation of chromatin to construct mature sperm with species-specific shape. During spermiogenesis, chromatin remodeling is a unique progress. It leads the nucleosome from a histone-based structure to a mostly protamine-based configuration. The main events of chromatin remodeling are the replacement of histone by histone variants, hyperacetylation, transient DNA strand breaks and repair, variants by transition proteins and finally by protamines. In this review, we synthesize and summarize the current knowledge on the progress of chromatin remodeling during spermiogenesis. We straighten out the chronological order of chromatin remodeling and illustrate the possible regulation mechanisms of each step.
•Histone replacement sets basis for subsequent histone modifications.•Hyperacetylation leads to the presence of loosening and opening chromatin.•The transient DNA strand break is an indispensable step for DNA relaxation.
Measurement-device-independent quantum key distribution (MDI-QKD), based on two-photon interference, is immune to all attacks against the detection system and allows a QKD network with untrusted ...relays. Since the MDI-QKD protocol was proposed, fiber-based implementations aimed at longer distance, higher key rates, and network verification have been rapidly developed. However, owing to the effect of atmospheric turbulence, MDI-QKD over a free-space channel remains experimentally challenging. Herein, by developing a robust adaptive optics system, high-precision time synchronization and frequency locking between independent photon sources located far apart, we realized the first free-space MDI-QKD over a 19.2-km urban atmospheric channel, which well exceeds the effective atmospheric thickness. Our experiment takes the first step toward satellite-based MDI-QKD. Moreover, the technology developed herein opens the way to quantum experiments in free space involving long-distance interference of independent single photons.
Human KIF4 is a member of Kinesin-4 kinesin family. The highly conserved structure contains an N-terminal motor region, coiled-coil region and C-terminal loading region. KIF4 plays important roles in ...DNA repair and DNA replication, which maintains genetic stability. KIF4 is also essential for regulation of mitosis and meiosis. KIF4 cooperates with condensin I and TopoIIα to help with chromosomal condensation, and binds to a plethora of cell-cycle proteins to regulate spindle organization and cytokinesis. Additionally, KIF4 plays roles in germ plasm aggregation and radial order in germ cells. In neuronal cells, KIF4 promotes proper axon growth by transporting substrates P0 and L1 to their proper location. Interestingly, KIF4 is abnormally expressed in a variety of cancers, where KIF4 is often up-regulated but can also be down-regulated in some cancers. This suggests distinctive regulatory mechanisms for different cancers. Recent studies support important roles for KIF4 in cancers such as the promotion of drug resistance or inhibition of apoptosis. Previous studies showed that by inhibiting or enhancing the expression of KIF4, the proliferation of cancer cells can be significantly reduced. Therefore KIF4 has potential as a therapeutic target for cancer therapy. Moreover, the misregulation of KIF4 is related to viral infection and neural system diseases like Alzheimer. We believe better understanding of this protein will help us develop better therapies for the diseases mentioned above. Here, we summarize KIF4 functions in normal cells and in various cancers, and provide an overview on the association between KIF4 disorders and disease progression.
•KIF4's cellular functions in cell cycle and development are summarized.•Relationship between KIF4 and various diseases such as cancer is illustrated.•Recent studies and controversial theories are summarized exhaustively.•KIF4's functions in cell cycle and development were specified via model and table.
A Lewis acid catalyzed carbofunctionalization of styrenes with diacyl peroxides and nucleophiles, including amines, indoles, trimethoxybenzenes, and carboxylic acid, has been accomplished. A wide ...range of primary, secondary, and tertiary alkyl diacyl peroxides generated from inexpensive aliphatic acids serve as both simple alkylating reagents and internal oxidants for the synthesis of value‐added amines, indoles, 1,1‐diarylalkanes, and esters in moderate to good yields. This protocol features site selectivity, broad substrate scope, and mild reaction conditions.
Conventional wastewater treatment plants (WWTPs) clean wastewater and minimize water pollution; but, while doing so, they also contribute to air pollution and need energy/material input with ...associated emissions. However, energy recovery (e.g. anaerobic digestion) and resource recovery (e.g. water reuse) allow us to offset the adverse environmental impacts of wastewater treatment. Life cycle assessments (LCA) have been used more and more to evaluate the environmental impacts of WWTPs and to suggest improvement options. There is a need to search for resource recovery applications that genuinely realize a net-zero impact on the total environment of WWTPs. In this work, a scheme with highly efficient energy and resource recovery (especially for thermal energy) is proposed and evaluated. The environmental impact of a conventional WWTP in comparison with the scheme proposed here, with energy/resource recovery included, was calculated, and discussed with reference to LCA methodology. In the process of using LCA, it was necessary to choose a regional situation to focus on. In this case, a Chinese situation was focused as a reference, but the qualitative information gained is of worldwide relevance. The results clearly revealed that conventional WWTP does not benefit the total environment as a whole while the new scheme benefited the total environment via resource/energy recovery-based processes. Among others, thermal energy recovery played a significant role towards a net-zero LCA analysis (contributing around 40%) which suggests that more attention and research should be focused on it.
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•Impacts of resource recovery on the environment was assessed by an improved LCA.•Resource recovery can help WWTPs in their goal of a zero net environmental impact.•Effluent reuse alone is not sufficient to attain a zero net environmental impact.•Thermal energy recovery would contribute the most to improving the impact of WWTPs.
•Yield, WUE and some fruit quality indices increase with irrigation frequency.•A proper water deficit improves nutritional and storage quality.•Optimal irrigation scheduling is obtained using the ...TOPSIS method.•Total soluble solids highly correlate with the comprehensive fruit quality score.
Vegetable production in many countries relies on irrigation. While increasing irrigation amount normally improves yield, too much water could jeopardize fruit quality and comprise profit. Optimizing irrigation frequency and amount is thus essential to ensuring yield increase without compromising fruit quality. This paper presents a three-year (2011–2013) experimental study on responsive changes in yield, fruit quality and water use efficiency (WUE) of tomato grown in greenhouse to different irrigation frequency and amount under drip irrigation. The irrigation scheduling was based on accumulative evaporation (AE) measured from a standard 20 cm pan. Three irrigation frequencies were considered in which irrigation was resumed when AE was 10 mm (I1), 20 mm (I2) and 30 mm (I3) respectively. Each frequency was associated with four irrigation amounts, which were 50% (Kcp1), 70% (Kcp2), 90% (Kcp3) and 110% (Kcp4) of AE respectively. Water consumption, yield characteristics and fruit quality of the plants in each treatment were measured. The three-year results show that for each irrigation amount, increasing irrigation frequency led to an increase in yield and WUE. Visual fruit-quality traits, including average weight, longitudinal and transverse diameter, increased with irrigation amount but not with irrigation frequency. It was found that a reduction in irrigation amount increased all other fruit quality characteristics except the sugar-organic acid ratio in 2013. Both yield and WUE increased asymptotically with irrigation amount before approaching their plateau when the irrigation amount reached 90% and 70% of AE respectively. While the yield was positively related to fruit size and negatively to soluble solid content, it was independent of WUE. The results from technique for order preference by similarity to ideal solution analysis revealed that among all treatments, I1+Kcp2 was the optimal in terms of best balancing yield, fruit quality and water use efficiency. Principal component analysis found that the comprehensive fruit quality score was closely related to the total soluble solids content.
Since the end of 2019, a highly contagious disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has deprived numerous lives worldwide, called COVID-19. Up to date, omicron ...is the latest variant of concern, and BA.5 is replacing the BA.2 variant to become the main subtype rampaging worldwide. These subtypes harbor an L452R mutation, which increases their transmissibility among vaccinated people. Current methods for identifying SARS-CoV-2 variants are mainly based on polymerase chain reaction (PCR) followed by gene sequencing, making time-consuming processes and expensive instrumentation indispensable. In this study, we developed a rapid and ultrasensitive electrochemical biosensor to achieve the goals of high sensitivity, the ability of distinguishing the variants, and the direct detection of RNAs from viruses simultaneously. We used electrodes made of MXene-AuNP (gold nanoparticle) composites for improved sensitivity and the CRISPR/Cas13a system for high specificity in detecting the single-base L452R mutation in RNAs and clinical samples. Our biosensor will be an excellent supplement to the RT-qPCR method enabling the early diagnosis and quick distinguishment of SARS-CoV-2 Omicron BA.5 and BA.2 variants and more potential variants that might arise in the future.
Due to their unique physicochemical properties, nanoparticles (NPs) have been increasingly developed for use in various fields. However, there has been both growing negative concerns with toxicity ...and positive realization of opportunities in nanomedicine, coming from the growing understanding of the associations between NPs and the human body, particularly relating to their cellular autophagic effects. This review summarizes NP-induced autophagy via the modulation of the mTOR signaling pathway and other associated signals including AMPK and ERK and also demonstrates how reactive oxygen species generation greatly underlies the regulation processes. The perspectives in this review aim to contribute to NP design, particularly in consideration of nanotoxicity and the potential for the precise application of NPs in nanomedicine.
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