•Adamts9 has a role in PGC migration in zebrafish.•Adamts9 is critical for the development and maintenance of ovarian follicles.•Adamts1, Adamts9, Mmp2, and Mmp9 change during gonadal development and ...ovulation.•Post-translational activation of metalloproteases is critical for their functions.•Multiple proteases complementing each other in their ECM targeting.
Changes in expression or activation of various metalloproteases including matrix metalloproteases (Mmp), a disintegrin and metalloprotease (Adam) and a disintegrin and metalloprotease with thrombospondin motif (Adamts), and their endogenous inhibitors (tissue inhibitors of metalloproteases, Timp), have been shown to be critical for ovulation in various species from studies in past decades. Some of these metalloproteases such as Adamts1, Adamts9, Mmp2, and Mmp9 have also been shown to be regulated by luteinizing hormone (LH) and/or progestin, which are essential triggers for ovulation in all vertebrate species. Most of these metalloproteases also express broadly in various tissues and cells including germ cells and somatic gonad cells. Thus, metalloproteases likely play roles in gonad formation processes comprising primordial germ cell (PGC) migration, development of germ and somatic cells, and sex determination. However, our knowledge on the functions and mechanisms of metalloproteases in these processes in vertebrates is still lacking. This review will summarize our current knowledge on the metalloproteases in ovulation and gonad formation with emphasis on PGC migration and germ cell development.
Stretchable electronics are attracting intensive attention due to their promising applications in many areas where electronic devices undergo large deformation and/or form intimate contact with ...curvilinear surfaces. On the other hand, a plethora of nanomaterials with outstanding properties have emerged over the past decades. The understanding of nanoscale phenomena, materials, and devices has progressed to a point where substantial strides in nanomaterial‐enabled applications become realistic. This review summarizes recent advances in one such application, nanomaterial‐enabled stretchable conductors (one of the most important components for stretchable electronics) and related stretchable devices (e.g., capacitive sensors, supercapacitors and electroactive polymer actuators), over the past five years. Focusing on bottom‐up synthesized carbon nanomaterials (e.g., carbon nanotubes and graphene) and metal nanomaterials (e.g., metal nanowires and nanoparticles), this review provides fundamental insights into the strategies for developing nanomaterial‐enabled highly conductive and stretchable conductors. Finally, some of the challenges and important directions in the area of nanomaterial‐enabled stretchable conductors and devices are discussed.
Recent progress with regard to nanomaterial‐enabled stretchable conductors and related stretchable devices is reviewed (e.g., capacitive sensors, supercapacitors and electroactive polymer actuators). Focusing on carbon nanomaterials (e.g., carbon nanotubes and graphene) and metal nanomaterials (e.g., metal nanowires and nanoparticles), this review provides fundamental insights into the strategies for developing nanomaterial‐enabled highly conductive and stretchable conductors.
A series of zirconium polyphenolate‐decorated‐(metallo)porphyrin metal–organic frameworks (MOFs), ZrPP‐n (n = 1, 2), featuring infinite ZrIV‐oxo chains linked via polyphenolate groups on four ...peripheries of eclipse‐arranged porphyrin macrocycles, are successfully constructed through a top–down process from simulation to synthesis. These are the unusual examples of Zr‐MOFs (or MOFs in general) based on phenolic porphyrins, instead of commonly known carboxylate‐based types. Representative ZrPP‐1 not only exhibits strong acid resistance (pH = 1, HCl) but also remains intact even when immersed in saturated NaOH solution (≈20 m), an exceptionally large range of pH resistance among MOFs. The metallation at the porphyrin core gives rise to materials with enhanced sorption and catalytic properties. In particular, ZrPP‐1‐Co, with precise and uniform distribution of active centers, exhibits not only high CO2 trapping capability (≈90 cm3 g−1 at 1 atm, 273 K, among the highest in Zr‐MOFs) but also high photocatalytic activity for reduction of CO2 into CO (≈14 mmol g−1 h−1) and high selectivity over CH4 (>96.4%) without any cocatalyst under visible‐light irradiation (λ > 420 nm). Given the strong chemical resistance under extreme alkali conditions, these catalysts can be recycled without appreciable loss of activity. The possible mechanism for photocatalytic reduction of CO2‐to‐CO over ZrPP‐1‐Co is also proposed.
Top–down fabrication of robust and porous materials based on infinite ZrIV‐polyphenolate chains linked via eclipsed‐arranged porphyrin macrocycles is presented. Among them, ZrPP‐1 retains its framework integrity when immersed in saturated NaOH solution as long as 1 week. Moreover, metallation at the porphyrin core gives rise to materials with enhanced CO2 trapping capability and high visible‐light‐driven CO2‐to‐CO photoreduction activity.
Considerable efforts have been made to achieve highly sensitive and wearable sensors that can simultaneously detect multiple stimuli such as stretch, pressure, temperature or touch. Here we develop ...highly stretchable multifunctional sensors that can detect strain (up to 50%), pressure (up to ∼1.2 MPa) and finger touch with high sensitivity, fast response time (∼40 ms) and good pressure mapping function. The reported sensors utilize the capacitive sensing mechanism, where silver nanowires are used as electrodes (conductors) and Ecoflex is used as a dielectric. The silver nanowire electrodes are screen printed. Our sensors have been demonstrated for several wearable applications including monitoring thumb movement, sensing the strain of the knee joint in patellar reflex (knee-jerk) and other human motions such as walking, running and jumping from squatting, illustrating the potential utilities of such sensors in robotic systems, prosthetics, healthcare and flexible touch panels.
Cropping systems have fertilized soils for decades with undetermined consequences for the productivity and functioning of terrestrial ecosystems. One of the critical unknowns is the role of soil ...biodiversity in controlling crop production after decades of fertilization. This knowledge gap limits our capacity to assess how changes in soil biodiversity could alter crop production and soil health in changing environments. Here, we used multitrophic ecological networks to investigate the importance of soil biodiversity, in particular, the biodiversity of key-stone taxa in controlling soil functioning and wheat production in a 35-year field fertilization experiment. We found strong and positive associations between soil functional genes, crop production and the biodiversity of key-stone phylotypes; soils supporting a larger number of key-stone nematode, bacteria and fungi phylotypes yielded the highest wheat production. These key-stone phylotypes were also positively associated with plant growth (phototrophic bacteria, nitrogen fixers) and multiple functional genes related to nutrient cycling. The retrieved information on the genomes clustered with key-stone bacterial phylotypes indicated that the key-stone taxa had higher gene copies of oxidoreductases (participating most biogeochemical cycles of ecosystems and linking to microbial energetics) and 71 essential functional genes associated with carbon, nitrogen, phosphorus, and sulfur cycling. Altogether, our work highlights the fundamental role of the biodiversity of key-stone phylotypes in maintaining soil functioning and crop production after several decades of fertilization, and provides a list of key-stone phylotypes linking to crop production and soil nutrient cycling, which could give science-based guidance for sustainable food production.
A highly conductive and stretchable conductor with silver nanowires (AgNWs) embedded just below the surface of poly(dimethylsiloxane) (PDMS) is fabricated. Stable conductivity of 5285 S cm−1 is ...achieved in a large range of tensile strain (0–50%) after a few cycles of stretching/releasing of the substrate. This stable electric response is due to buckling of the AgNW/PDMS thin layer, which is attributed to irreversible sliding of the AgNWs in the PDMS matrix. AgNWs can be printed to fabricate patterned stretchable conductors with feature size as small as 50 μm.
Microplastics are emerging pollutants that have recently aroused considerable concern but most toxicological studies have focused on marine biota, with little investigation of the influence of ...microplastics on terrestrial ecosystems. Here, we fed the soil oligochaete Enchytraeus crypticus with oatmeal containing 0, 0.025, 0.5, and 10% (dry weight basis) nano-polystyrene (0.05–0.1 μm particle size) to elucidate the impact of microplastics on the growth and gut microbiome of Enchytraeus crypticus. We observed a significant reduction of weight in the animals fed 10% polystyrene and an increase in the reproduction of those fed 0.025%. More importantly, using 16S rRNA amplification and high-throughput sequencing we found a significant shift in the microbiome of those fed 10% microplastics with significant decreases in the relative abundance of the families Rhizobiaceae, Xanthobacteraceae and Isosphaeraceae. These families contain key microbes that contribute to nitrogen cycling and organic matter decomposition.
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•Exposure to nano-polystyrene disrupted the Enchytraeus crypticus microbiome.•Nano-polystyrene led to a decrease in bacterial diversity and a structural shift.•Exposure to nano-polystyrene altered the weight and reproduction of E. crypticus.
Nano-polystyrene exposure disrupted the microbiome of Enchytraeus crypticus, leading to a decrease in microbial diversity and a structural shift in bacterial composition.
Microbial mass movements Zhu, Yong-Guan; Gillings, Michael; Simonet, Pascal ...
Science (American Association for the Advancement of Science),
09/2017, Letnik:
357, Številka:
6356
Journal Article
Recenzirano
Odprti dostop
Wastewater, tourism, and trade are moving microbes around the globe at an unprecedented scale
For several billion years, microorganisms and the genes they carry have mainly been moved by physical ...forces such as air and water currents. These forces generated biogeographic patterns for microorganisms that are similar to those of animals and plants (
1
). In the past 100 years, humans have changed these dynamics by transporting large numbers of cells to new locations through waste disposal, tourism, and global transport and by modifying selection pressures at those locations. As a consequence, we are in the midst of a substantial alteration to microbial biogeography. This has the potential to change ecosystem services and biogeochemistry in unpredictable ways.
Printed electronics is attracting a great deal of attention in both research and commercialization as it enables fabrication of large‐scale, low‐cost electronic devices on a variety of substrates. ...Printed electronics plays a critical role in facilitating widespread flexible electronics and more recently stretchable electronics. Conductive nanomaterials, such as metal nanoparticles and nanowires, carbon nanotubes, and graphene, are promising building blocks for printed electronics. Nanomaterial‐based printing technologies, formulation of printable inks, post‐printing treatment, and integration of functional devices have progressed substantially in the recent years. This review summarizes basic principles and recent development of common printing technologies, formulations of printable inks based on conductive nanomaterials, deposition of conductive inks via different printing techniques, and performance enhancement by using various sintering methods. While this review places emphasis on conductive nanomaterials, the printing techniques and ink formulations can be applied to other materials such as semiconducting and insulating nanomaterials. Moreover, some applications of printed flexible and stretchable electronic devices are reviewed to illustrate their potential. Finally, the future challenges and prospects for printing conductive nanomaterials are discussed.
Printing of nanomaterials for flexible and stretchable electronics, including metal‐based and carbon nanomaterials, is summarized in this review along with challenges and opportunities. A variety of printing techniques, formulation of printable inks, and post‐printing treatment of the printed patterns are reviewed. Printing and integration of functional devices are also presented.
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