Publications by authors named "Xiaoke Ding"

Due to the plethora of nitrogen (N), phosphorus (P), potassium (K) in urine, it is bound to trigger phosphorus coprecipitation, thereby adversely affecting K-struvite purity in the coprecipitates. To obtain high pure K-struvite, the present study was to innovatively explore the effect of residual NH concentration, pH and initial Mg concentration on phosphorus coprecipitation in synthetic urine. Importantly, a Back-Propagation Artificial Neural Network (BPANN) model was innovatively proposed to simulate and predict crystal purities in the coprecipitates.

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Microbial fuel cell (MFC) and subsequent struvite crystallization are available low-carbon environmental- friendly techniques for resource utilization of waste activated sludge (WAS). In this study, low temperature thermo-alkaline pretreatment (LTTAP) was innovatively proposed for enhancing MFC electricity generation and subsequent struvite crystallization from WAS. The results indicated that LTTAP at 75 °C and pH 10 not only substantially shortened the start-up time of MFC to 3-4 days, but also significantly increased maximum power density to 5.

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Autoproteolysis has been discovered to play key roles in various biological processes, but functional autoproteolysis has been rarely reported for transmembrane signaling in prokaryotes. In this study, an autoproteolytic effect was discovered in the conserved periplasmic domain of anti-σ factor RsgIs from , which was found to transmit extracellular polysaccharide-sensing signals into cells for regulation of the cellulosome system, a polysaccharide-degrading multienzyme complex. Crystal and NMR structures of periplasmic domains from three RsgIs demonstrated that they are different from all known proteins that undergo autoproteolysis.

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Loop-mediated isothermal amplification (LAMP) is a nucleic acid amplification technique that has been widely used for the detection of pathogens in many organisms. Current LAMP-based sensors usually require the LAMP products to be labeled in order for them to be detected. Here, we present a novel label-free LAMP chip, which consists of a nanopore thin-film sensor embedded inside a LAMP reaction chamber.

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We report a method to fabricate silicon micro-nanostructures of different shapes by tuning the number of layers and the sizes of self-assembled polystyrene beads, which serve as the mask, and by tuning the reactive ion etching (RIE) time. This process is simple, scalable, and inexpensive without using any sophisticated nanomanufacturing equipment. Specifically, in this work, we demonstrate the proposed process by fabricating silicon micro- or nanoflowers, micro- or nanobells, nanopyramids, and nanotriangles using a self-assembled monolayer or bilayer of polystyrene beads as the mask.

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Because of the physiological and anatomical constraints of the eye, ophthalmic drug delivery is challenging. When applied topically, less than 1% of administered ophthalmic drugs reach the aqueous humor. The delivery of a drug within an efficient therapeutic concentration, to the required site of action, for an extended period of time, is complicated.

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The σ70 family alternative σI factors and their cognate anti-σI factors are widespread in Clostridia and Bacilli and play a role in heat stress response, virulence, and polysaccharide sensing. Multiple σI/anti-σI factors exist in some lignocellulolytic clostridial species, specifically for regulation of components of a multienzyme complex, termed the cellulosome. The σI and anti-σI factors are unique, because the C-terminal domain of σI (SigIC) and the N-terminal inhibitory domain of anti-σI (RsgIN) lack homology to known proteins.

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This Letter reports a method to significantly improve the optical resolution of the anodic aluminum oxide (AAO) nanopore thin film sensor based on multi-cavity Fabry-Perot interference. The newly designed sensor is fabricated by bonding a layer of transparent polymer thin film (pTF), which is polydimethylsiloxane (PDMS), to a transparent AAO thin film to form a flexible pTF-nanopore sensor. In comparison with the AAO nanopore thin film sensor, the pTF-nanopore sensor shows a much-improved quality (Q) factor and optical resolution.

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The cellulosome of Clostridium thermocellum is an elegant and efficient multi-enzyme complex for degrading lignocellulose. The cellulosome contains several dozens of carbohydrate hydrolysis enzymes, which are regulated by the presence of environmental substrates through several pairs of sigma and anti-sigma factors. The anti-sigma factors sense the presence of substrates and transduce the signals into the cell.

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