bluuebunny/crossref_metadata_2025 huggingface dataset:
NO, thiols and disulfides
Authors: Girard Pierre , Potier Pierre
Published: July 2002

The chemical nature of the messenger molecule, nitric oxide (NO), and especially its reactivity towards thiol groups and disuifides, could explain, at least partly, its intervention in so many different biological processes. NO can be regarded as the smallest molecule suitable for electron transport in biological systems. The S‐nitrosation reaction and its reverse reaction represent the most convenient general way to store, to transport and finally to release NO. Nitric oxide is also particularly convenient for playing a role in interconversions of thiol groups and disulfides in chain radical or oxidation‐reduction processes, and to be subsequently engaged in complex sequences of reactions accounting for different biological situations.
Effects of heavy metals on Tetraselmis suecica: Ultrastructural and energy‐dispersive X‐ray spectroscopic studies
Authors: Nassiri Youssef , Ginsburger‐Vogel Thomas , Mansot Jean Louis , We´ry Jany
Published: July 2002

Summry— The influence of metal contamination on the marine alga Tetraselmis suecica was investigated at physiological and ultrastructural levels. For this analysis, the growth response of this microalga was studied after the addition of various concentrations of heavy metals (Cd, Cu). The concentration corresponding to 50% growth inhibition (IC50) and the number of days per cell cycle (Td) studied, revealed that the toxic effects of copper are heavier than those of cadmium. In the case of copper contamination, the Td grows with increasing metal concentration in the culture medium, while it remains unchanged during the cadmium contamination. The toxicity of cadmium, only observed in the latency phase of growth, suggests an adaptation phenomenon of T suecica to this metal. Ultrastructural changes in response to pollutants were investigated; copper induced cytoplasmic vacuolisation, organelle changes, appearance of cells with multilayered cell walls and excretion of organic matter. In the case of cadmium contamination, ultrastructural changes mainly affected the osmiophilic vesicles, of which both number and volume increased with increasing metal concentration in the culture medium. The results of X‐ray microanalysis revealed that Cd and Cu were strongly present in excreted organic matter and osmiophilic vesicles. The latter can be excreted during cell division, thus participating in detoxification processes. Intracellular cadmium incorporation proved that some toxic effects of this metal are a result of interaction with endogenous cellular constituents. In the case of copper contamination, the presence of copper in walls of a multilayered cell suggests that these structures constitute an additionnal adsorbing area for this element, reducing metal free concentration in the medium. Mechanisms of metal detoxification of Tetraselmis suecica are discussed.
Psychopathology measured by established self-rating scales and correlated to serotonin measures in patients with fibromyalgia
Authors: Krag NJ , Nørregaard J , Hindberg I , Larsen JK , Danneskiold-Samsøe B
Published: July 2002

The objective of the study was to evaluate the presence of psychopathology in fibromyalgia patients compared to a control group of rheumatic patients with pain. Forty-nine fibromyalgia patients and 33 controls were evaluated using established self-rating scales. Serotonin was determined using a radioenzymatic method. Fibromyalgia patients scored significantly higher than the controls on the majority of the subscales on the SCL-90, the two subscales on the Spielberger State and Trait Anxiety Inventory, the GHQ 12 scale and on a visual analogue pain scale. In a multivariate analysis the somatization dimension followed by the state anxiety accounted for the highest difference. Platelet-poor plasma serotonin, platelet serotonin and platelet uptake index were not significantly different between the groups. In conclusion, fibromyalgia patients presented quantitatively more psychopathology than the control group on a wide range of psychopathologic axes, and this cannot solely be accounted for by their higher level of pain.
Cost-effectiveness in the treatment of schizophrenia
Authors: Knapp MRJ
Published: July 2002

This paper discusses the need for a health economics perspective and some of the central methodological issues raised by economic appraisals, including cost-effectiveness and cost-utility analyses. It illustrates how cost-effectiveness studies can inform policy and practice decisions concerning the treatment of schizophrenia, focusing on five generic evaluation questions commonly raised. Examples are drawn from recent and current UK research.
Molecular organization of the human serotonin transporter at the air/water interface
Authors: Faivre Vincent , Rosilio Véronique , Manivet Philippe , Langevin Dominique , Launay Jean-Marie , Baszkin Adam
Published: July 2002

The serotonin transporter (SERT) is the target of several important antidepressant and psychostimulant drugs. It has been shown that under defined conditions, the transporter spread at the air/water interface was able to bind its specific ligands. In this paper, the interfacial organization of the protein has been assessed from dynamic surface pressure and ellipsometric measurements. For areas comprising between 10 400 and 7100 Å2/molecule, ellipsometric measurements reveal an important change in the thickness of the SERT film. This change was attributed to the reorientation of the transporter molecules from a horizontal to their natural predictive transmembrane orientation. The thickness of the SERT film at 7100 Å2/molecule was found to be approximately equal to 84 Å and coincided well with the theoretical value estimated from the calculations based on the dimensions of α‐helices containing membrane proteins. These data suggest that the three‐dimensional arrangement of the SERT may be represented as a box with lengths dz
=83–85 Å and dy
or dx
=41–47 Å.
Nitric oxide synthase activity in mitochondria
Authors: Ghafourifar Pedram , Richter Christoph
Published: July 2002

In the present study we show the existence of a functional nitric oxide synthase (NOS) in rat liver mitochondria. The enzyme uses l‐arginine (l‐arg) to produce nitric oxide (NO) and l‐citrulline, and is Ca2+‐dependent. l‐Arg analogues, N
ω‐monomethyl‐l‐arg and N
ω‐nitro‐l‐arg, inhibit the enzyme, and d‐arginine is not a substrate for it. We found mitochondrial NOS (mtNOS) activity associated with the inner mitochondrial membrane but not with the matrix fraction. In intact, succinate‐energized mitochondria, the enzyme is constitutively active and exerts substantial control over mitochondrial respiration and membrane potential. The activity is further stimulated when Ca2+ is taken up by mitochondria. We suggest that the existence of mtNOS and its Ca2+ dependence are highly relevant for mitochondrial functioning.
CFTR mRNA and its truncated splice variant (TRN‐CFTR) are differentially expressed during collecting duct ontogeny
Authors: Huber Stephan , Braun Gerald , Burger-Kentischer Anke , Reinhart Brigitte , Luckow Bruno , Horster Michael
Published: July 2002

The collecting duct epithelium originates from the embryonic ureter by branching morphogenesis. Ontogeny‐dependent changes of CFTR mRNA expression were assessed by quantitative reverse transcriptase‐polymerase chain reaction (RT‐PCR) in primary monolayer cultures of rat ureteric buds (UB) and cortical collecting ducts, microdissected at different embryonic and postnatal developmental stages. The amount of wild‐type CFTR‐specific PCR product in UB declined to 20% of the initial value between embryonic gestational day E15 and postnatal day P1. After birth the CFTR product increased transiently between P1 and P7 by a factor of 10 and decreased towards day P14. PCR products specific for TRN‐CFTR, a truncated splice variant, however, were low in early embryonic cells, increased markedly between day E17 and P2, and reached a plateau postnatally. Therefore, mRNA encoding TRN‐CFTR does not appear to have a specific embryonic‐morphogenetic function. By contrast, such function is suggested for wild‐type CFTR mRNA as its abundance was high in early embryonic nephrogenesis, as well as during a postnatal period shortly before branching morphogenesis is completed.
Calcitonin gene‐related peptide decreases expression of acetylcholinesterase in mammalian myotubes
Authors: Boudreau-Larivière Céline , Jasmin Bernard J
Published: July 2002

Nerve‐derived trophic factors are known to modulate expression of acetylcholinesterase (AChE) in skeletal muscle fibers, yet the precise identity of these factors remains elusive. In the present study, we treated mouse C2 myotubes with calcitonin gene‐related peptide (CGRP). Compared to non‐treated myotubes, cell‐associated AChE activity levels were decreased by ∼60% after 48 h of treatment. A parallel reduction in AChE total protein levels was also observed as determined by Western blot analysis. The reduction in AChE activity was due to a decrease in the levels of the G1 molecular form and to an elimination of G4. By contrast, levels of secreted AChE remained unchanged following CGRP treatment. Finally, the overall decrease in AChE activity was accompanied by a reduction in AChE transcripts which could not be attributed to changes in the transcriptional rate of the ACHE gene.
Effects of IL‐1 receptor‐associated kinase (IRAK) expression on IL‐1 signaling are independent of its kinase activity
Authors: Knop J. , Martin M.U.
Published: July 2002

Interleukin‐1 (IL‐1) stimulates the association of the IL‐1 receptor‐associated protein kinase (IRAK) with the heterodimer of IL‐1RI and IL‐1RAcP via the adapter protein MyD88. In the receptor complex IRAK becomes heavily phosphorylated and concomitantly activated. Here we show that overexpression of a kinase‐inactive mutant of IRAK (K239S) inhibits neither IL‐1‐stimulated activation of the transcription factor NF‐κB, nor that of the c‐Jun N‐terminal kinase nor IL‐2 production in murine EL‐4 cells, but enhances these effects in a manner comparable to wild type IRAK. This strongly suggests that the intrinsic kinase activity is not required for downstream signaling via IRAK.
Characterization of purified and unidirectionally reconstituted Pho84 phosphate permease of Saccharomyces cerevisiae
Authors: Fristedt Ulrika , Weinander Rolf , Martinsson Hanna-Stina , Persson Bengt L.
Published: July 2002

Hydropathy analysis of the amino acid sequence of the Pho84 phosphate permease of Saccharomyces cerevisiae suggests that the protein consists of 12 transmembrane domains connected by hydrophilic loops. The Pho84 protein has been modified by a gene fusion approach, yielding two different N‐terminal His‐tagged chimeras which can be expressed in Escherichia coli, purified and functionally reconstituted into defined proteoliposomes. The continuous epitopes in the N‐ and C‐terminal sequences of the Pho84 chimeras were shown to be accessible in proteoliposomes containing the purified active Pho84 proteins. Site‐specific proteolysis of the immunoreactive N‐terminal sequence in the reconstituted protein suggests a unidirectional insertion into liposomes.
Current reversible contraceptive methods: a global perspective
Authors: Huezo C.M
Published: July 2002

Since the 1960's there have been important gains in the efforts to make the benefits of family planning accessible to people around the world. However, prevalence of contraceptive use is still low in some areas, especially in sub‐Saharan Africa. Making contraceptives accessible through good quality services should be a goal for reproductive health programs. In the absence of an ideal method of contraception which would suit every individual, there is a variety of contraceptive methods with advantages in some aspects and disadvantages in others from which people should be able to choose according to their particular characteristics and needs. Important aspects to take into consideration include effectiveness, convenience, and safety. In general, the most effective methods are more likely to have some side effects and method‐related complications. However, when weighing the risks and benefits, the most effective methods have greater benefits on the health of women by protecting them better from the health risks of unwanted pregnancies. Most methods also have non‐contraceptive benefits — for instance, combined oral contraceptives (COCs) provide important degrees of protection against endometrial and ovarian cancers, benign breast disease, pelvic inflammatory disease (PID), and ectopic pregnancy. They also reduce menstrual blood loss. Although barrier methods have lower effectiveness against pregnancy, their most important advantage is the protection they can provide against sexually transmitted diseases. The male condom in particular (and probably the female condom) has the special value of providing protection against HIV infection. This paper describes reversible methods of contraception including possible health risks and contraindications. Adequate counseling, however, is essential for people to make an appropriate choice of contraception and to secure safe and effective use of the method.
Activation of neurospecific gene expression by antennapedia homeobox peptide
Authors: Biagioni Stefano , Ciuffini Laura , De Jaco Antonella , Vignoli Anna Lidia , Augusti‐Tocco Gabriella
Published: July 2002

Antennapedia homeobox peptide has been reported to enhance neurite outgrowth and branching. Thus it is of interest to investigate whether antennapedia peptide is capable of modulating the expression of genes related to different events of neuronal development. In this paper we report the enhancement of a 68 KDa neurofilament subunit, choline acetyltransferase and acetylcholinesterase expression in spinal cord neurons, elicited by antennapedia peptide. Modulation of gene expression is different with respect to each gene product analyzed, suggesting a specific action of the peptide on diverse genes controlling different events of neuronal differentiation.
Disruption of the relationship between renin and atrial natriuretic peptide early in the course of ventricular dysfunction
Authors: Dutka David P. , Puri Sundeep , Strong Rachel , Cleland John G.F.
Published: July 2002

Background:

Plasma renin activity is normal in left ventricular dysfunction in the absence of diuretic therapy. In health there is a reciprocal relationship between renin and atrial natriuretic peptide (ANP) but a positive correlation in advanced heart failure. The relationship between renin and ANP in mild left ventricular dysfunction is unknown.

Methods and Results:

Patients with left ventricular dysfunction (n = 35, 18 without diuretic therapy) were compared to 20 age‐matched healthy subjects. Plasma concentrations of active renin (PARC), ANP and norepinephrine were measured after 20 min rest and 45 min after an infusion of normal saline (10 ml/kg body wt.). Basal plasma ANP was increased in patients with left ventricular dysfunction compared to healthy subjects, whether or not they were receiving diuretics. PARC was similar in healthy controls and patients untreated with diuretics but was increased in diuretic treated patients. After saline loading in healthy subjects PARC fell while ANP rose. Patients with left ventricular dysfunction had a smaller decline in PARC, that did not achieve statistical significance, but had a greater increase in plasma ANP compared to healthy subjects (P < 0.05). The close reciprocal relationship between PARC and ANP observed in healthy subjects before and after saline loading (r = 0.8, P < 0.001 and r = 0.6, P < 0.01) was weakened in those not receiving diuretics (r = 0.4, P < 0.05 and r = 0.24, ns) and lost in those receiving diuretics (r = 0.1 and r = 0.08).

Conclusions:

Patients with left ventricular dysfunction have a disturbance of the normal reciprocal relationship between PARC and ANP which antedates diuretic treatment. This should be taken into account when interpreting plasma neuroendocrine measurements in patients with ventricular dysfunction.
A comprehensive analysis of SNPs and CNVs identifies novel markers associated with disease outcomes in colorectal cancer
Authors: Yu Yajun , Werdyani Salem , Carey Megan , Parfrey Patrick , Yilmaz Yildiz E. , Savas Sevtap
Published: July 2021

We aimed to examine the associations of a genome‐wide set of single nucleotide polymorphisms (SNPs) and 254 copy number variations (CNVs) and/or insertion/deletions (INDELs) with clinical outcomes in colorectal cancer patients (n = 505). We also aimed to investigate whether their associations changed (e.g., appeared, diminished) over time. Multivariable Cox proportional hazards and piece‐wise Cox regression models were used to examine the associations. The Cancer Genome Atlas (TCGA) datasets were used for replication purposes and to examine the gene expression differences between tumor and nontumor tissue samples. A common SNP (WBP11‐rs7314075) was associated with disease‐specific survival with P‐value of 3.2 × 10−8. Association of this region with disease‐specific survival was also detected in the TCGA patient cohort. Two expression quantitative trait loci (eQTLs) were identified in this locus that were implicated in the regulation of ERP27 expression. Interestingly, expression levels of ERP27 and WBP11 were significantly different between colorectal tumors and nontumor tissues. Three SNPs predicted the risk of recurrent disease only after 5 years postdiagnosis. Overall, our study identified novel variants, one of which also showed an association in the TCGA dataset, but no CNVs/INDELs, that associated with outcomes in colorectal cancer. Three SNPs were candidate predictors of long‐term recurrence/metastasis risk.
The influence of white matter hyperintensity on cognitive impairment in Parkinson's disease
Authors: Liu Hailing , Deng Bin , Xie Fen , Yang Xiaohua , Xie Zhenchao , Chen Yonghua , Yang Zhi , Huang Xiyan , Zhu Shuzhen , Wang Qing
Published: July 2021

The aim of this meta‐analysis was to review systematically and to identify the relationship between the severity and location of white matter hyperintensities (WMHs) and the degree of cognitive decline in patients with Parkinson’s disease (PD). We searched the PubMed, EMBASE, Web of Science, Ovid, and Cochrane Library databases for clinical trials of the severity and location of WMHs on the degree of cognitive impairment in PD through October 2020. We conducted the survey to compare the association of WMH burden in patients with PD with mild cognitive impairment (PD‐MCI) versus those with normal cognition (PD‐NC) and in patients with PD with dementia (PDD) versus those with PD without dementia (PD‐ND). Nine studies with PD‐MCI versus PD‐NC and 10 studies with PDD versus PD‐ND comparisons were included. The WMH burden in PD‐MCI patients was significantly different compared to that in PD‐NC patients (standard mean difference, SMD = 0.39, 95% CI: 0.12 to 0.66, p = 0.005), while there was no correlation shown in the age‐matched subgroup of the comparison. In addition, PDD patients had a significantly higher burden of WMHs (SMD = 0.8, 95% CI: 0.44 to 1.71, p < 0.0001), especially deep white matter hyperintensities (SMD = 0.54, 95% CI: 0.36 to 0.73, p < 0.00001) and periventricular hyperintensities (SMD = 0.70, 95% CI: 0.36 to 1.04, p < 0.0001), than PD‐NC patients, regardless of the adjustment of age. WMHs might be imaging markers for cognitive impairment in PDD but not in PD‐MCI, regardless of age, vascular risk factors, or race. Further prospective studies are needed to validate the conclusions.
Engineered Polymeric Carbon Nitride Additive for Energy Storage Materials: A Review
Authors: Wang Zhonghao , Jin Bingjun , Peng Jun , Su Wan , Zhang Kan , Hu Xun , Wang Guannan , Park Jong Hyeok
Published: July 2021

The ever‐increasing demands for high energy density electronics have motivated research on exploring new types of electrode materials featuring mechanical flexibility and electrical storage capability. Of these, polymeric carbon nitride (PCN) has been increasingly studied in regard to electrical energy storage (EES) because of its abundant pyridinic N content, which is beneficial for enhancing electrochemical performance. However, state‐of‐the‐art PCN‐based electrode materials for EES are still far from industrial requirements. Herein, the current status of PCN‐based materials in batteries and supercapacitors (SCs) is primarily discussed. A particular emphasis is placed on the PCN processing into composite electrode materials, including the defect engineering of pristine PCN and its coupling with other conductive materials to develop heterojunction nanostructures, which is essential for developing highly efficient electrode materials. Moreover, the direct pyrolysis of PCN into N‐doped graphene with a tunable N content is introduced and achieves remarkable energy storage performance with superior electronic conductivity. Furthermore, the energy storage mechanisms for batteries and SCs are also highlighted to reveal structure–performance relationship. Finally, this comprehensive review outlines the remaining challenges and strategies for future improvements in PCN‐based materials in this emerging field. This review will provide inspiration on developing future PCN‐based materials for EES.
Mechanically Robust and Flexible Films of Ionic Liquid‐Modulated Polymer Thermoelectric Composites
Authors: Li Zhipeng , Deng Liang , Lv Haicai , Liang Lirong , Deng Wenjiang , Zhang Yichuan , Chen Guangming
Published: July 2021

In the recent decade, polymer thermoelectric (TE) composite has witnessed explosive achievements to address energy generation and utilization. Besides the significant progress in enhancement of TE performance, the high mechanical property has received increasing attention, being important for practical applications in complex environments. However, the mechanical performance has always been improved at the sacrifice of TE performance, and vice versa, which poses a great challenge. Here, ionic liquid (IL)‐assisted fabrication of flexible films of polymer TE composites with simultaneously high TE and mechanical performances based on poly(3,4‐ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS), polyvinyl alcohol (PVA), and single‐walled carbon nanotubes (SWCNTs) are reported. The resultant composite shows a high TE performance with a power factor of 106.1 ± 8.2 µW m−1 K−2 at room temperature, and strong mechanical robustness with a tensile modulus of 4.2 ± 0.5 GPa and fracture strength of 136.5 ± 10.6 MPa. It is the most mechanically robust TE composite known with such a high power factor in the available literature. The present study provides a promising way to help address the longstanding and intractable issue of inferior mechanical performance of TE composites without compromising TE performance.
Enhancing the Stabilization Potential of Lyophilization for Extracellular Vesicles
Authors: Trenkenschuh Eduard , Richter Maximilian , Heinrich Eilien , Koch Marcus , Fuhrmann Gregor , Friess Wolfgang
Published: July 2021

Extracellular vesicles (EV) are an emerging technology as immune therapeutics and drug delivery vehicles. However, EVs are usually stored at −80 °C which limits potential clinical applicability. Freeze‐drying of EVs striving for long‐term stable formulations is therefore studied. The most appropriate formulation parameters are identified in freeze‐thawing studies with two different EV types. After a freeze‐drying feasibility study, four lyophilized EV formulations are tested for storage stability for up to 6 months. Freeze‐thawing studies revealed improved colloidal EV stability in presence of sucrose or potassium phosphate buffer instead of sodium phosphate buffer or phosphate‐buffered saline. Less aggregation and/or vesicle fusion occurred at neutral pH compared to slightly acidic or alkaline pH. EVs colloidal stability can be most effectively preserved by addition of low amounts of poloxamer 188. Polyvinyl pyrrolidone failed to preserve EVs upon freeze‐drying. Particle size and concentration of EVs are retained over 6 months at 40 °C in lyophilizates containing 10 mm K‐ or Na‐phosphate buffer, 0.02% poloxamer 188, and 5% sucrose. The biological activity of associated beta‐glucuronidase is maintained for 1 month, but decreased after 6 months. Here optimized parameters for lyophilization of EVs that contribute to generate long‐term stable EV formulations are presented.
The Action‐Networks of Nanosilver: Bridging the Gap between Material and Biology
Authors: Cao Huiliang , Qin Hui , Li Yongsheng , Jandt Klaus D.
Published: July 2021

The emergence of nanosilver (silver in nanoscale shapes and their assemblies) benefits the landscape of modern healthcare; however, this brings about concerns over its safety issues associated with an ultrasmall size and high mobility. By reviewing previous reporting details about the synthesis and characterization of nanosilver and its biological responses, a gap between materials synthesis and their biomedical uses is characterized by the insufficient understanding of the interacting and interplaying nanoscale actions of silver. To improve reporting quality and advance clinical translations, it is suggested that researchers have a comprehensive recognition of the “Indications for use” before designing innovative nanosilver‐based materials and an “Action‐network” concept addressing the acting range and strength of those nanoscale actions is implemented. Although this discussion is specific to nanosilver, the idea of “Indications for use” centered design and synthesis is generally applicable to other biomedical nanomaterials.
Current‐Driven Organic Electrochemical Transistors for Monitoring Cell Layer Integrity with Enhanced Sensitivity
Authors: Lieberth Katharina , Romele Paolo , Torricelli Fabrizio , Koutsouras Dimitrios A. , Brückner Maximilian , Mailänder Volker , Gkoupidenis Paschalis , Blom Paul W. M.
Published: July 2021

In this progress report an overview is given on the use of the organic electrochemical transistor (OECT) as a biosensor for impedance sensing of cell layers. The transient OECT current can be used to detect changes in the impedance of the cell layer, as shown by Jimison et al. To circumvent the application of a high gate bias and preventing electrolysis of the electrolyte, in case of small impedance variations, an alternative measuring technique based on an OECT in a current‐driven configuration is developed. The ion‐sensitivity is larger than 1200 mV V‐1dec‐1 at low operating voltage. It can be even further enhanced using an OECT based complementary amplifier, which consists of a p‐type and an n‐type OECT connected in series, as known from digital electronics. The monitoring of cell layer integrity and irreversible disruption of barrier function with the current‐driven OECT is demonstrated for an epithelial Caco‐2 cell layer, showing the enhanced ion‐sensitivity as compared to the standard OECT configuration. As a state‐of‐the‐art application of the current‐driven OECT, the in situ monitoring of reversible tight junction modulation under the effect of drug additives, like poly‐l‐lysine, is discussed. This shows its potential for in vitro and even in vivo toxicological and drug delivery studies.
Programmable Mechanically Active Hydrogel‐Based Materials
Authors: Dong Yixiao , Ramey‐Ward Allison N. , Salaita Khalid
Published: July 2021

Programmable mechanically active materials (MAMs) are defined as materials that can sense and transduce external stimuli into mechanical outputs or conversely that can detect mechanical stimuli and respond through an optical change or other change in the appearance of the material. Programmable MAMs are a subset of responsive materials and offer potential in next generation robotics and smart systems. This review specifically focuses on hydrogel‐based MAMs because of their mechanical compliance, programmability, biocompatibility, and cost‐efficiency. First, the composition of hydrogel MAMs along with the top‐down and bottom‐up approaches used for programming these materials are discussed. Next, the fundamental principles for engineering responsivity in MAMS, which includes optical, thermal, magnetic, electrical, chemical, and mechanical stimuli, are considered. Some advantages and disadvantages of different responsivities are compared. Then, to conclude, the emerging applications of hydrogel‐based MAMs from recently published literature, as well as the future outlook of MAM studies, are summarized.
Comment on “Eppur si Muove: Proton Diffusion in Halide Perovskite Single Crystals”: Eppur Non si Muove: A Critical Evaluation of Proton Diffusion in Halide Perovskite Single Crystals
Authors: Buffeteau Thierry , Hirsch Lionel , Bassani Dario M.
Published: July 2021

A recent report by Cahen and co‐workers is examined that finds the diffusion constant for proton migration in methylammonium lead triiodide single crystals to be 2 × 105‐fold greater than that previously reported by Sadhu et al. By comparing the conversion of single crystals versus microcrystalline samples, it is concluded that proton diffusion in macroscopic single crystals is accelerated by the presence of defects acting as high‐diffusivity paths.
New Structure Mass Tag based on Zr‐NMOF for Multiparameter and Sensitive Single‐Cell Interrogating in Mass Cytometry
Authors: Dang Jingqi , Li Hongxia , Zhang Lulu , Li Sijie , Zhang Ting , Huang Shiyi , Li Yiyang , Huang Chengjie , Ke Yuqing , Shen Guangxia , Zhi Xiao , Ding Xianting
Published: July 2021

Mass cytometry, also called cytometry by time‐of‐flight (CyTOF), is an emerging powerful proteomic analysis technique that utilizes metal chelated polymer (MCP) as mass tags for interrogating high‐dimensional biomarkers simultaneously on millions of individual cells. However, under the typical polymer‐based mass tag system, the sensitivity and multiplexing detection ability has been highly restricted. Herein, a new structure mass tag based on a nanometal organic framework (NMOF) is reported for multiparameter and sensitive single‐cell biomarker interrogating in CyTOF. A uniform‐sized Zr‐NMOF (33 nm) carrying 105 metal ions is synthesized under modulator/reaction time coregulation, which is monodispersed and colloidally stable in water for over one‐year storage. On functionalization with an antibody, the Zr mass tag exhibits specific molecular recognition properties and minimal cross‐reaction toward nontargeted cells. In addition, the Zr‐mass tag is compatible with MCP mass tags in a multiparameter assay for mouse spleen cells staining, which exploits four additional channels, m/z = 90, 91, 92, 94, for single‐cell immunoassays in CyTOF. Compared to the MCP mass tag, the Zr‐mass tag provides an additional fivefold signal amplification. This work provides the fundamental technical capability for exploiting NMOF‐based mass tags for CyTOF application, which opens up possibility of high‐dimensional single‐cell immune profiling, low abundant antigen detection, and development of new barcoding systems.
Controlling Surface Wettability for Automated In Situ Array Synthesis and Direct Bioscreening
Authors: Lin Weilin , Gandhi Shanil , Oviedo Lara Alan Rodrigo , Thomas Alvin K. , Helbig Ralf , Zhang Yixin
Published: July 2021

The in situ synthesis of biomolecules on glass surfaces for direct bioscreening can be a powerful tool in the fields of pharmaceutical sciences, biomaterials, and chemical biology. However, it is still challenging to 1) achieve this conventional multistep combinatorial synthesis on glass surfaces with small feature sizes and high yields and 2) develop a surface which is compatible with solid‐phase syntheses, as well as the subsequent bioscreening. This work reports an amphiphilic coating of a glass surface on which small droplets of polar aprotic organic solvents can be deposited with an enhanced contact angle and inhibited motion to permit fully automated multiple rounds of the combinatorial synthesis of small‐molecule compounds and peptides. This amphiphilic coating can be switched into a hydrophilic network for protein‐ and cell‐based screening. Employing this in situ synthesis method, chemical space can be probed via array technology with unprecedented speed for various applications, such as lead discovery/optimization in medicinal chemistry and biomaterial development.
The Wet‐Oxidation of a Cu(111) Foil Coated by Single Crystal Graphene
Authors: Luo Da , Wang Xiao , Li Bao‐Wen , Zhu Chongyang , Huang Ming , Qiu Lu , Wang Meihui , Jin Sunghwan , Kim Minhyeok , Ding Feng , Ruoff Rodney S.
Published: July 2021

The wet‐oxidation of a single crystal Cu(111) foil is studied by growing single crystal graphene islands on it followed by soaking it in water. 18O‐labeled water is also used; the oxygen atoms in the formed copper oxides in both the bare and graphene‐coated Cu regions come from water. The oxidation of the graphene‐coated Cu regions is enabled by water diffusing from the edges of graphene along the bunched Cu steps, and along some graphene ripples where such are present. This interfacial diffusion of water can occur because of the separation between the graphene and the “step corner” of bunched Cu steps. Density functional theory simulations suggest that adsorption of water in this gap is thermodynamically stable; the “step‐induced‐diffusion model” also applies to graphene‐coated Cu surfaces of various other crystal orientations. Since bunched Cu steps and graphene ripples are diffusion pathways for water, ripple‐free graphene is prepared on ultrasmooth Cu(111) surfaces and it is found that the graphene completely shields the underlying Cu from wet‐oxidation. This study greatly deepens the understanding of how a graphene‐coated copper surface is oxidized, and shows that graphene completely prevents the oxidation when that surface is ultrasmooth and when the graphene has no ripples or wrinkles.
Au‐Doped Ag2Te Quantum Dots with Bright NIR‐IIb Fluorescence for In Situ Monitoring of Angiogenesis and Arteriogenesis in a Hindlimb Ischemic Model
Authors: Yang Hongchao , Huang Haoying , Ma Xiang , Zhang Yejun , Yang Xiaohu , Yu Mengxuan , Sun Ziqiang , Li Chunyan , Wu Feng , Wang Qiangbin
Published: July 2021

Fluorescence located in 1500–1700 nm (denoted as the near‐infrared IIb window, NIR‐IIb) has drawn great interest for bioimaging, owing to its ultrahigh tissue penetration depth and spatiotemporal resolution. Therefore, NIR‐IIb fluorescent probes with high photoluminescence quantum yield (PLQY) and stability along with high biocompatibility are urgently pursued. Herein, a novel NIR‐IIb fluorescent probe of Au‐doped Ag2Te (Au:Ag2Te) quantum dots (QDs) is developed via a facile cation exchange method. The Au dopant concentration in the Ag2Te QDs is tunable from 0% to 10% by controlling the ratio of supplied Au precursor to Ag2Te QDs, resulting in a wide range of PL emission in the NIR‐IIb window and a much‐enhanced PL intensity. After surface modification, the Au:Ag2Te QDs possess bright NIR‐IIb emission, high colloidal stability and photostability, and decent biocompatibility. Further, in vivo monitoring of the process of angiogenesis and arteriogenesis in an ischemic hindlimb is successfully performed.
Dynamic Structural Color Display Based on Femtosecond Laser Variable Polarization Processing
Authors: Wu Peichao , Cao Xiaowen , Zhao Ling , Chen Zhihao , Zhang Mina , Juodkazis Saulius , Zhang Wenwu
Published: July 2021

Vivid structural colors, inspired by butterflies, which can display iridescent colors dynamically when white light illuminates the surface with subwavelength period ripples, have attracted significant interest for its potential application in the fields of information storage, anti‐counterfeiting, etc. However, there is still a huge demand for the development of multipattern dynamically transformable display surfaces using a versatile method. A new scheme based on femtosecond laser combined with variable polarization processing has been proposed. This scheme enables a surface with a structural color function that can be easily prepared by adjusting the polarization of the laser via a half‐wave plate. Four types of structural units with designated periodic orientations are written on the same sample to exhibit four different colorful images. Through experiment and analysis, it is demonstrated that different colors can be displayed by changing the observation angle, and a multi‐pattern display can be realized by rotating the sample. The lithography‐free inscribed patterns show a strong azimuthal angular sensitivity to color and its brightness. This work demonstrates that femtosecond laser surface structuring provides a versatile platform to create various micro/nanostructures on a solid surface, and this technique can be used for the biomimetic lithography‐free processing of any material using ablation.
Fabrication of Non‐Uniform Nanolattices with Spatially Varying Geometry and Material Composition
Authors: Chen I‐Te , Dai Zijian , Lee Dennis T. , Chen Yi‐An , Parsons Gregory N. , Chang Chih‐Hao
Published: July 2021

The fabrication of periodic 3D nanostructures with uniform material properties has been widely investigated and is important for applications in photonics, mechanics, and energy storage. However, creating nanostructures with spatially varying lattice geometry and material composition is still largely an unexplored challenge in nanofabrication. This work presents the fabrication of non‐uniform nanolattices by patterning multiple layers of 3D nanostructures using phase shift lithography and atomic layer deposition. By controlling the processing parameters, the lattice geometry and material composition of each individual nanolattice layer can be tailored to create arbitrary material property profiles. Using the proposed method, a five‐layer nanolattice with spatially varying porosity and oxide materials has been demonstrated. This process can be used to create gradient‐index antireflection nanostructures, and a fabricated four‐layer nanolattice structure consisting of TiO2 and Al2O3 with gradually varying porosity reduces more than 90% of the specular reflectance from a silicon substrate. By enabling nanolattices with arbitrary profiles in physical properties, the demonstrated technique can find broad applications in nanophotonics, graded filters, energy storage systems, and nanoarchitected films.
Multifunctional Optical Polymeric Films with Photochromic, Fluorescent, and Ultra‐Long Room Temperature Phosphorescent Properties
Authors: Wu Bo , Xu Xingtang , Tang Yiyuan , Han Xiaolin , Wang Guojie
Published: July 2021

Photochromism, fluorescence, and ultra‐long room temperature phosphorescence (URTP) are attractive phenomena in photonics. However, achieving multiple optical properties such as photochromism, fluorescence, and URTP on one material still remains a challenge. Here, the authors report a multifunctional optical polymeric film with photochromic, fluorescent, and URTP properties, fabricated by simply doping the naphthopyran molecule into epoxy polymer with 3D network. When the polymer network is loose, the naphthopyran‐doped film exhibits photochromic property but no fluorescence and phosphorescence. When the polymer network becomes dense, the film shows fluorescent and URTP behaviors but no photochromic property. It is noted that the room temperature phosphorescence lifetime is as high as 604 ms. Based on the excellent optical properties of reversible photochromism, fluorescence, and URTP, an advanced sixfold encryption application has been successfully established. This work not only opens up a new direction in design and fabrication of multifunctional optical materials but also offers principles for developing organic optical materials toward multilevel information encryption and data storage.
Copper(II)‐Mediated Intermolecular Radical [3+2]‐Annulation of N,N‐Dimethyl Enaminones: Direct Access to 5‐Acyl‐3‐Furancarboxaldehydes
Authors: Zhang Biao , Zhou Pan , Xu Hui , Huang Jiuzhong , Sun Yulin , Liu Donghan , Yu Fuchao
Published: July 2021

Copper(II)‐mediated unprecedented intermolecular radical [3+2] annulation of N,N‐dimethyl enaminones has been developed. The protocol is promoted simply by copper(II) chloride to access 5‐acyl‐3‐furancarboxaldehydes with acceptable to good yields and broad substrate scope. This reaction allows the formation of multiple new bonds, including C(sp2)−O bond between two nucleophilic sites, C(sp2)−C(sp2) bond and C=O bond, through a radical cyclization process. Moreover, gram‐synthesis and application research show the potential application value of this transformation in industry.

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Mechanistic Investigation of Electrostatic Field‐Enhanced Water Evaporation
Authors: Fei Jipeng , Ding Bin , Koh See Wee , Ge Junyu , Wang Xingli , Lee Liquan , Sun Zixu , Yao Mengqi , Chen Yonghao , Gao Huajian , Li Hong
Published: July 2021

Investigations on external electrostatic field (EEF)‐enhanced liquid water evaporation have been reported decades ago, which suggest that molecular alignment and polarization tuned by EEF accelerating the phase change process could be responsible for EEF‐enhanced water evaporation. However, a detailed study revealing the role of EEF in altering the intermolecular and intramolecular water structure is lacking. Herein, an EEF is proved to tune water state by accelerating the thermal movement of water molecules, lowering the molecular escaping energy, and loosening the hydrogen bond structure. The detailed mechanisms and field interactions (heat and electrostatic) are investigated by in situ Raman characterizations and molecular dynamic simulations, which reveal that an EEF can effectively reduce the free energy barrier of water evaporation and then increase the evaporated water molecule flux. As a proof of concept, an EEF is integrated into an interfacial two‐dimentional solar steam generator, enhancing the efficiency by up to 15.6%. Similar to a catalyst lowing activation energy and enhancing kinetics of a chemical reaction, the EEF enhances water state tuning, lowers evaporation enthalpy, and then boosts steam generation rate with negligible additional energy consumption, which can serve as a generic method for water evaporation enhancement in water harvesting, purification, and beyond.
Osmium‐ and Cobalt‐Terpyridine‐Based Electrochromic Devices for “Smart” Signage Application: The Effect of Lighting on Color Perception
Authors: Laschuk Nadia O. , Ebralidze Iraklii I. , Easton E. Bradley , Zenkina Olena V.
Published: July 2021

Modern electrochromic devices (ECDs) have found a wide range of applications, which are not limited to the traditional design of “smart” windows and self‐dimming mirrors. Novel cutting‐edge applications in optoelectronics and particularly in low‐energy displays and “smart” signage require electrochromic materials (ECMs) that demonstrate significant changes in optical density, fast switching times, and color differences between the colored and bleached states that are visible to the naked eye. Here ECMs that are designed by the chemical deposition of electrochromic Co(II) and Os(II) complexes and their mixture on surface‐enhanced support fabricated by screen printing of indium–tin oxide (ITO‐50) nanoparticles are presented on an ITO/glass substrate. The oxidation state of the metal complexes is reversibly addressed by voltage switching between −1 and +3 V. Further assembly of the ECMs and ITO/glass counter electrode using gel electrolyte results in solid‐state ECDs. The changes in optical properties of these ECDs induced by the metal oxidation state alteration are tracked by recording UV–vis spectra. Moreover, here color differences (CDs) and changes in luminance of ECDs (ΔL) in the colored and bleached state are compared when illuminated with light‐emitting diodes (LEDs) of different colors.
Bismuth Sulfide Strongly Coupled to Functionalized MWNTs Hybrids with Improved Thermoelectric Properties
Authors: Liao Yu , Liu Wenting , Jia Weiping , Wang Bo , Chen Ling , Huang Ke , Montgomery Matthew J. , Qian Jun , Lv Song , Pfefferle Lisa D.
Published: July 2021

The efficiency of thermoelectric (TE) materials depends on an interplay between various material properties, and strategies for co‐optimizing these properties will be necessary for implementing these materials in the future. In this work, bismuth sulfide (Bi2S3) and acid treated multiwalled carbon nanotube (f‐MWNT) composites are fabricated by wet chemical synthesis at room temperature. Bi2S3 is intimately anchored onto the surface of the f‐MWNT to form a coaxial nanostructure. The power factor of the composite is enhanced relative to both the pure Bi2S3 and MWNTs, due to a large enhancement of the electrical conductivity. The enhanced conductivity is attributed to restructuring of the bismuth (Bi) and oxygen (O) bonding environments when Bi2S3 is chemically interfaced with the f‐MWNTs, suggestive of the formation of a strongly coupled complex via BiO/BiS bonds. Strong‐coupling is further supported by scanning transmission electron microscopy, Raman, and diffuse reflectance spectroscopy, which reveal fast charge‐transfer between the Bi2S3 and MWNT when interfaced together. These results support material compositing as a potential strategy for engineering enhanced TE materials.
How will regulation influence commercial viability of autonomous equipment in US production agriculture?
Authors: Shockley Jordan , Dillon Carl , Lowenberg‐DeBoer James , Mark Tyler
Published: July 2021

Autonomous equipment for crop production is on the brink of commercialization in the United States but federal, state, and local policies could affect commercial viability and hinder adoption. This article examines the farm‐level implications of both a speed restriction and on‐site supervisory regulations. The rules reduce the profitability of autonomous machinery, and for some scenarios autonomous machines are no longer an economically viable alternative to conventional machinery. Regulations also increase the optimal number autonomous machines required and influence production practices. Smaller farms have more flexibility in supporting the rules because they have more to gain from the use of autonomous equipment.
Erythroferrone and hepcidin as mediators between erythropoiesis and iron metabolism during allogeneic hematopoietic stem cell transplant
Authors: Pirotte Michelle , Fillet Marianne , Seidel Laurence , Jaspers Aurélie , Baron Fréderic , Beguin Yves
Published: July 2021

Hematopoietic cell transplantation (HCT) brings important alterations in erythropoiesis and iron metabolism. Hepcidin, which regulates iron metabolism, increases in iron overload or inflammation and decreases with iron deficiency or activated erythropoiesis. Erythroferrone (ERFE) is the erythroid regulator of hepcidin. We investigated erythropoiesis and iron metabolism after allogeneic HCT in 70 patients randomized between erythropoietin (EPO) treatment or no EPO, by serially measuring hepcidin, ERFE, CRP (inflammation), soluble transferrin receptor (sTfR, erythropoiesis), serum iron and transferrin saturation (Tsat; iron for erythropoiesis) and ferritin (iron stores). We identified biological and clinical factors associated with serum hepcidin and ERFE levels. Serum ERFE correlated overall with sTfR and reticulocytes and inversely with hepcidin. Erythroferrone paralleled sTfR levels, dropping during conditioning and recovering with engraftment. Inversely, hepcidin peaked after conditioning and decreased during engraftment. Erythroferrone and hepcidin were not significantly different with or without EPO. Multivariate analyses showed that the major determinant of ERFE was erythropoiesis (sTfR, reticulocytes or serum Epo). Pretransplant hepcidin was associated with previous RBC transfusions and ferritin. After transplantation, the major determinants of hepcidin were iron status (ferritin at all time points and Tsat at day 56) and erythropoiesis (sTfR or reticulocytes or ERFE), while the impact of inflammation was less clear and clinical parameters had no detectable influence. Hepcidin remained significantly higher in patients with high compared to low pretransplant ferritin. After allogeneic HCT with or without EPO therapy, significant alterations of hepcidin occur between pretransplant and day 180, in correlation with iron status and inversely with erythroid ERFE.