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The Mechanism of Piezocatalysis: Energy Band Theory or Screening Charge Effect?

Wang K, Han C, Li J, Qiu J, Sunarso J, Liu S

Angew Chem Int Ed Engl, 2022 Feb 01;61(6):e202110429.
PMID: 34612568 DOI: 10.1002/anie.202110429

Piezocatalysis, a newly emerging catalysis technology that relies on the piezopotential and piezoelectric properties of the catalysts, is attracting unprecedented research enthusiasm for applications in energy conversion, organic synthesis, and environmental remediation. Despite the rapid development in the past three years, the mechanism of piezocatalysis is still under debate. A fundamental understanding of the working principles of this technology should enable the future design and optimization of piezocatalysts. Herein, we provide an overview of the two popular theories used to explain the observed piezocatalysis: energy band theory and screening charge effect. A comprehensive discussion and clarification of the differences, relevance, evidence, and contradiction of the two mechanisms are provided. Finally, challenges and perspectives for future mechanistic studies are highlighted. Hopefully, this Review can help readers gain a better understanding of piezocatalysis and enable its application in their own research.
Fulltext The use of protein-DNA, chromatin immunoprecipitation, and transcriptome arrays to describe transcriptional circuits in the dehydrated male rat hypothalamus

Qiu J, Kleineidam A, Gouraud S, Yao ST, Greenwood M, Hoe SZ, et al.

Endocrinology, 2014 Nov;155(11):4380-90.
PMID: 25144923 DOI: 10.1210/en.2014-1448

The supraoptic nucleus (SON) of the hypothalamus is responsible for maintaining osmotic stability in mammals through its elaboration of the antidiuretic hormone arginine vasopressin. Upon dehydration, the SON undergoes a function-related plasticity, which includes remodeling of morphology, electrical properties, and biosynthetic activity. This process occurs alongside alterations in steady state transcript levels, which might be mediated by changes in the activity of transcription factors. In order to identify which transcription factors might be involved in changing patterns of gene expression, an Affymetrix protein-DNA array analysis was carried out. Nuclear extracts of SON from dehydrated and control male rats were analyzed for binding to the 345 consensus DNA transcription factor binding sequences of the array. Statistical analysis revealed significant changes in binding to 26 consensus elements, of which EMSA confirmed increased binding to signal transducer and activator of transcription (Stat) 1/Stat3, cellular Myelocytomatosis virus-like cellular proto-oncogene (c-Myc)-Myc-associated factor X (Max), and pre-B cell leukemia transcription factor 1 sequences after dehydration. Focusing on c-Myc and Max, we used quantitative PCR to confirm previous transcriptomic analysis that had suggested an increase in c-Myc, but not Max, mRNA levels in the SON after dehydration, and we demonstrated c-Myc- and Max-like immunoreactivities in SON arginine vasopressin-expressing cells. Finally, by comparing new data obtained from Roche-NimbleGen chromatin immunoprecipitation arrays with previously published transcriptomic data, we have identified putative c-Myc target genes whose expression changes in the SON after dehydration. These include known c-Myc targets, such as the Slc7a5 gene, which encodes the L-type amino acid transporter 1, ribosomal protein L24, histone deactylase 2, and the Rat sarcoma proto-oncogene (Ras)-related nuclear GTPase.
Weedy rice, a hidden gold mine in the paddy field

Wu D, Qiu J, Sun J, Song BK, Olsen KM, Fan L

Mol Plant, 2022 Jan 12.
PMID: 35032686 DOI: 10.1016/j.molp.2022.01.008
Fulltext Longitudinal outcomes for educational placement and quality of life in a prospectively recruited multinational cohort of children with cochlear implants

Muller L, Goh BS, Cordovés AP, Sargsyan G, Sikka K, Singh S, et al.

Int J Pediatr Otorhinolaryngol, 2023 Jul;170:111583.
PMID: 37245391 DOI: 10.1016/j.ijporl.2023.111583

OBJECTIVES: The aim of this study was to report on the educational placement, quality of life and speech reception changes in a prospectively recruited group of children after they received a cochlear implant (CI).
METHOD: Data was collected on 1085 CI recipients of as part of a prospective, longitudinal, observational, international, multi-centre, paediatric registry, initiated by Cochlear Ltd (Sydney, NSW, Australia). Outcome data from children (≤10 years old) implanted in routine practice was voluntarily entered into a central, externally hosted, e-platform. Collection occurred prior to initial device activation (baseline) and at six monthly follow-up intervals up to 24 months and then at 3 years post activation. Clinician reported baseline and follow up questionnaires and Categories of Auditory Performance version II (CAP-II) outcomes were collated. Self-reported evaluation forms and patient information were provided by the parent/caregiver/patient via the implant recipient baseline and follow up, Children Using Hearing Implants Quality of Life (CuHIQoL) and Speech Spatial Qualities (SSQ-P) Parents Version questionnaires.
RESULTS: Children were mainly bilaterally profoundly deaf, unilaterally implanted and used a contralateral hearing aid. Prior to implant 60% used signing or total communication as their main mode of communication. Mean age at implant was 3.2 ± 2.2 years (range 0-10 years). At baseline 8.6% were in mainstream education with no additional support and 82% had not yet entered school. After three years of implant use, 52% had entered mainstream education with no additional support and 38% had not yet entered school. In the sub-group of 141 children who were implanted at or after three years of age and were thus old enough to be in mainstream school at the three-year follow up, an even higher proportion (73%) were in mainstream education with no support. Quality of life scores for the child improved statistically significantly post implant compared to baseline and continued to improve significantly at each interval up to 3 years (p
Silver Nanowire Networks with Moisture-Enhanced Learning Ability

Qiu J, Li J, Li W, Wang K, Xiao T, Su H, et al.

ACS Appl Mater Interfaces, 2024 Feb 28;16(8):10361-10371.
PMID: 38362885 DOI: 10.1021/acsami.3c17438

The human brain possesses a remarkable ability to memorize information with the assistance of a specific external environment. Therefore, mimicking the human brain's environment-enhanced learning abilities in artificial electronic devices is essential but remains a considerable challenge. Here, a network of Ag nanowires with a moisture-enhanced learning ability, which can mimic long-term potentiation (LTP) synaptic plasticity at an ultralow operating voltage as low as 0.01 V, is presented. To realize a moisture-enhanced learning ability and to adjust the aggregations of Ag ions, we introduced a thin polyvinylpyrrolidone (PVP) coating layer with moisture-sensitive properties to the surfaces of the Ag nanowires of Ag ions. That Ag nanowire network was shown to exhibit, in response to the humidity of its operating environment, different learning speeds during the LTP process. In high-humidity environments, the synaptic plasticity was significantly strengthened with a higher learning speed compared with that in relatively low-humidity environments. Based on experimental and simulation results, we attribute this enhancement to the higher electric mobility of the Ag ions in the water-absorbed PVP layer. Finally, we demonstrated by simulation that the moisture-enhanced synaptic plasticity enabled the device to adjust connection weights and delivery modes based on various input patterns. The recognition rate of a handwritten data set reached 94.5% with fewer epochs in a high-humidity environment. This work shows the feasibility of building our electronic device to achieve artificial adaptive learning abilities.
Fulltext Diverse genetic mechanisms underlie worldwide convergent rice feralization

Qiu J, Jia L, Wu D, Weng X, Chen L, Sun J, et al.

Genome Biol, 2020 03 26;21(1):70.
PMID: 32213201 DOI: 10.1186/s13059-020-01980-x

BACKGROUND: Worldwide feralization of crop species into agricultural weeds threatens global food security. Weedy rice is a feral form of rice that infests paddies worldwide and aggressively outcompetes cultivated varieties. Despite increasing attention in recent years, a comprehensive understanding of the origins of weedy crop relatives and how a universal feralization process acts at the genomic and molecular level to allow the rapid adaptation to weediness are still yet to be explored.
RESULTS: We use whole-genome sequencing to examine the origin and adaptation of 524 global weedy rice samples representing all major regions of rice cultivation. Weed populations have evolved multiple times from cultivated rice, and a strikingly high proportion of contemporary Asian weed strains can be traced to a few Green Revolution cultivars that were widely grown in the late twentieth century. Latin American weedy rice stands out in having originated through extensive hybridization. Selection scans indicate that most genomic regions underlying weedy adaptations do not overlap with domestication targets of selection, suggesting that feralization occurs largely through changes at loci unrelated to domestication.
CONCLUSIONS: This is the first investigation to provide detailed genomic characterizations of weedy rice on a global scale, and the results reveal diverse genetic mechanisms underlying worldwide convergent rice feralization.
Fulltext Osmoregulation requires brain expression of the renal Na-K-2Cl cotransporter NKCC2

Konopacka A, Qiu J, Yao ST, Greenwood MP, Greenwood M, Lancaster T, et al.

J Neurosci, 2015 Apr 01;35(13):5144-55.
PMID: 25834041 DOI: 10.1523/JNEUROSCI.4121-14.2015

The Na-K-2Cl cotransporter 2 (NKCC2) was thought to be kidney specific. Here we show expression in the brain hypothalamo-neurohypophyseal system (HNS), wherein upregulation follows osmotic stress. The HNS controls osmotic stability through the synthesis and release of the neuropeptide hormone, arginine vasopressin (AVP). AVP travels through the bloodstream to the kidney, where it promotes water conservation. Knockdown of HNS NKCC2 elicited profound effects on fluid balance following ingestion of a high-salt solution-rats produced significantly more urine, concomitant with increases in fluid intake and plasma osmolality. Since NKCC2 is the molecular target of the loop diuretics bumetanide and furosemide, we asked about their effects on HNS function following disturbed water balance. Dehydration-evoked GABA-mediated excitation of AVP neurons was reversed by bumetanide, and furosemide blocked AVP release, both in vivo and in hypothalamic explants. Thus, NKCC2-dependent brain mechanisms that regulate osmotic stability are disrupted by loop diuretics in rats.
Cu(I)/Cu(II) Creutz-Taube Mixed-Valence 2D Coordination Polymers

Li N, Wu G, Xi S, Wei F, Lin M, Qiu J, et al.

Small Methods, 2023 Jan;7(1):e2201166.
PMID: 36543365 DOI: 10.1002/smtd.202201166

Graphene-like 2D coordination polymers (GCPs) have been of central research interest in recent decades with significant impact in many fields. According to classical coordination chemistry, Cu(II) can adopt the dsp2 hybridization to form square planar coordination geometry, but not Cu(I); this is why so far, there has been few 2D layered structures synthesized from Cu(I) precursors. Herein a pair of isostructural GCPs synthesized by the coordination of benzenehexathiol (BHT) ligands with Cu(I) and Cu(II) ions, respectively, is reported. Spectroscopic characterizations indicate that Cu(I) and Cu(II) coexist with a near 1:1 ratio in both GCPs but remain indistinguishable with a fractional oxidation state of +1.5 on average, making these two GCPs a unique pair of Creutz-Taube mixed-valence 2D structures. Based on density functional theory calculations, an intramolecular pseudo-redox mechanism is further uncovered whereby the radicals on BHT ligands can oxidize Cu(I) or reduce Cu(II) ions upon coordination, thus producing isostructures with distinct electron configurations. For the first time, it is demonstrated that using Cu(I) or Cu(II), one can achieve 2D isostructures, indicating an unusual fact that a neutral periodic structure can host a different number of total electrons as ground states, which may open a new chapter for 2D materials.
Fulltext Genomic insights into the evolution of Echinochloa species as weed and orphan crop

Wu D, Shen E, Jiang B, Feng Y, Tang W, Lao S, et al.

Nat Commun, 2022 02 03;13(1):689.
PMID: 35115514 DOI: 10.1038/s41467-022-28359-9

As one of the great survivors of the plant kingdom, barnyard grasses (Echinochloa spp.) are the most noxious and common weeds in paddy ecosystems. Meanwhile, at least two Echinochloa species have been domesticated and cultivated as millets. In order to better understand the genomic forces driving the evolution of Echinochloa species toward weed and crop characteristics, we assemble genomes of three Echinochloa species (allohexaploid E. crus-galli and E. colona, and allotetraploid E. oryzicola) and re-sequence 737 accessions of barnyard grasses and millets from 16 rice-producing countries. Phylogenomic and comparative genomic analyses reveal the complex and reticulate evolution in the speciation of Echinochloa polyploids and provide evidence of constrained disease-related gene copy numbers in Echinochloa. A population-level investigation uncovers deep population differentiation for local adaptation, multiple target-site herbicide resistance mutations of barnyard grasses, and limited domestication of barnyard millets. Our results provide genomic insights into the dual roles of Echinochloa species as weeds and crops as well as essential resources for studying plant polyploidization, adaptation, precision weed control and millet improvements.