bluuebunny/crossref_metadata_2025 huggingface dataset:
The nuclear origin of the non‐phosphorylating NADH dehydrogenases of plant mitochondria
Authors: Cook-Johnson R.J , Zhang Q , Wiskich J.T , Soole K.L
Published: July 2002

The oxidation of matrix and cytosolic NADH by isolated beetroot and wheat leaf mitochondria was investigated to determine whether the rotenone‐insensitive NADH dehydrogenases of plant mitochondria were the products of nuclear or mitochondrial genes. After aging beetroot tissue (slicing and incubating in a CaSO4 solution), the induction of the level of matrix NADH oxidation in the presence of rotenone was greatly reduced in mitochondria isolated from tissue treated with cycloheximide, a nuclear protein synthesis inhibitor. This was also true for the oxidation of cytosolic NADH. Mitochondria isolated from chloramphenicol‐treated tissue exhibited greatly increased levels of both matrix and external rotenone‐insensitive NADH oxidation when compared to the increase due to the aging process alone. This increase was not accompanied by an increase in matrix NAD‐linked substrate dehydrogenases such as malic enzyme nor intra‐mitochondrial NAD levels. Possible explanations for this increase in rotenone‐insensitive NADH oxidation are discussed. Based on these results we have concluded that the matrix facing rotenone‐insensitive NADH dehydrogenase of plant mitochondria is encoded by a nuclear gene and synthesis of the protein occurs in the cytosol.
Solution conformation on bovine growth hormone releasing factor by 1H NMR and molecular modeling
Authors: Kweon Jeehye , Lee Ho-Jin , Kim Young-Man , Choi Young-Sang , Lee Kang-Bong
Published: July 2002

The structure of bovine growth hormone releasing factor (bGHRF) consisting of 44 amino acids has been studied in CD and 1H nuclear magnetic resonance (NMR) spectroscopy in conjunction with molecular modeling. Since bGHRF does not have an ordered structure in water alone, a 30% 2,2,2‐trifluoroethanol (TFE) aqueous solvent was used to induce considerable α‐helical structures, which corresponds to a helical content of ∼62% as determined by circular dichroism (CD). The secondary structure was obtained from nuclear Overhauser enhancement and 3JHNα coupling constant in 30% TFE solution. Three‐dimensional structures consistent with NMR data were generated by using distance geometry calculation. A set of 267 interproton distances derived from nuclear Overhauser effect correlation spectroscopy (NOESY) experiments and coupling constants were used. From the initial random conformations, 50 distance geometry structures with minimal violations were selected for further refinement. The 14 best structures were obtained after simulated annealing calculation with energy minimization. The structure of bGHRF in 30% TFE solution was characterized by one α‐helix (residues 8–19), two poorly constrained helices (residues 23–27 and residues 31–34) and a β I(III)‐turn fragment (residues 20–23; φ
i+1=−53.1°, Ψ
i+1=−19.6°, φ
i+2=−59.9°, Ψ
i+2=−20.6°) connected by the segments of less defined structures in N‐terminal and Ω‐shaped flexible C‐terminal determined from NOESY cross peaks between helical segment (residues 14–18) and tail fragment (residues 42–44). The obtained structure will play an important role toward the understanding of the structural and functional role of the GHRF.
MyoD binds to Mos and inhibits the Mos/MAP kinase pathway
Authors: Solhonne Brigitte , Lenormand Jean Luc , Pelpel Karine , Leibovitch Marie Pierre , Leibovitch Serge A.
Published: July 2002

When ectopically expressed, the serine/threonine kinase Mos can induce oncogenic transformation of somatic cells by direct phosphorylation of MAP kinase/ERK kinase (MEK1), activating the mitogen‐activated protein kinases ERK1 and ERK2. On the other hand, overexpression of Mos in C2C12 myoblasts is not transforming. Mos activates myogenic differentiation by promoting heterodimerization of the MyoD/E12 proteins, increasing the expression of myogenic markers and the positive autoregulatory loop of MyoD. In this study, we show that in myogenic cells, the mitogenic and oncogenic signalling from the Mos/MEK/ERK pathway is suppressed by MyoD through the formation of a heterotrimeric complex.
N‐terminus of mature heat‐labile enterotoxin chain B is critical for its extracellular secretion in Vibrio cholerae
Authors: Mukhija Reema , Garg Lalit C
Published: July 2002

The effects of addition of a few amino acids to the amino‐ and carboxy‐terminal regions of the mature portion of the heat‐labile enterotoxin chain B (LTB) of Escherichia coli on protein export, secretion and assembly were investigated. In E. coli, LTB (secretory protein) with or without the extension at the N‐ or C‐terminus accumulated in the periplasmic fraction. For Vibrio cholerae, LTB with the extension at the C‐terminus was exported to the periplasm followed by secretion to the extracellular milieu. However, LTB with the N‐terminus extension was exported to the periplasm only. Our findings suggest that in the case of V. cholerae, the N‐terminus of the mature LTB plays an important role in its secretion to the extracellular milieu.
Activation volumes for intramolecular electron transfer in bovine heart cytochrome c oxidase
Authors: Larsen Randy W
Published: July 2002

The present work examines the activation volumes associated with intramolecular electron transfer (ET) within the CO‐mixed‐valence form of bovine heart cytochrome c oxidase (CcO). Activation volumes for intramolecular ET between cytochrome a
3 and cytochrome a (k=(6.7±0.9)×105 s−1 at ambient pressure) and between cytochrome a and CuA (k=(5.9±1.7)×104 s−1) are found to be +41±5 ml/mol and +28±4 ml/mol, respectively. Examination of the crystal structures of both the fully oxidized and fully reduced forms of bovine heart CcO suggest that the activation volume for the ET between cytochrome a
3 and cytochrome a arises from structural changes localized at cytochrome a
3 upon heme reduction. Similarly, the activation volume for the ET between cytochrome a and CuA is primarily due to structural changes localized at CuA upon reduction of this site. Reduction/oxidation of cytochrome a does not appear to make any significant contribution to the activation volume. Overall, these results suggest conformational regulation of ET by both CuA and cytochrome a
3 but not cytochrome a.
Isochore specificity of AUG initiator context of human genes
Authors: Pesole Graziano , Bernardi Giorgio , Saccone Cecilia
Published: July 2002

The efficiency of AUG start codon recognition in translation initiation is modulated by its sequence context. Here we investigated a non‐redundant set of 5914 human genes and show that this context is different in genes located in different isochores. In particular, of the two main consensus start sequences, RCCaugR is five‐fold more represented than AARaugR in genes from the GC‐rich H3 isochores compared to genes from the GC‐poor L isochores. Furthermore, genes located in GC‐rich isochores have shorter 5′ UTRs and stronger avoidance of upstream AUG than genes located in GC‐poor isochores. This suggests that genes requiring highly efficient translation are located in GC‐rich isochores and genes requiring fine modulation of expression are located in GC‐poor isochores. This is in agreement with independent data from the literature concerning the location of housekeeping and tissue‐specific genes, respectively.
Characterization of morphogenetic and invasive abilities of human mammary epithelial cells: Correlation with variations of urokinase‐type plasminogen activator activity and type‐1 plasminogen activator inhibitor level
Authors: Fauquette William , Bourhis Xuefen Dong‐Le , Delannoy‐Courdent Albine , Boilly Bénoni , Desbiens Xavier
Published: July 2002

Urokinase‐type plasminogen activator (uPA) and one of its inhibitors, the PAI‐1, are involved in the proteolytic cascade of matrix degradation during in vivo morphogenesis or metastasis. In the present study, we have characterized the in vitro morphological behavior of human normal and malignant mammary epithelial cells and determined the levels of uPA activity and PAI‐1 during these events. Two‐dimensional cultures in the presence of inductive fibroblast‐conditioned medium (CM) allowed migration of HBL‐100 cells and MDA‐MB‐231 cells. Normal human mammary epithelial cells (HMEC) and MCF‐7 cells failed to migrate under these conditions. The epithelial cell migration correlated with an increase in the uPA activity whereas their immobility correlated with both increases in uPA activity and PAI‐1 level. In three‐dimensional cultures in collagen gel, fibroblasts or fibroblast CM induced branching tubular morphogenesis to HMEC, cord‐like extensions to HBL‐100 cells and a greater invasiveness ability to MDA‐MB‐231 cells. These events correlated with an increased uPA activity. In contrast, no morphological rearrangement was observed in MCF‐7 cells and this correlated with both increases in uPA activity and PAI‐1 level. Altogether, these results show that the in vitro mammary epithelial behavior is under the influence of mesenchymal inductive signals and is in agreement with modifications of uPA activity and PAI‐1 levels. Our culture system gives a suitable model to study the mechanisms of mammary development and metastasis and to highlight the involvement of proteases and their inhibitors in cell‐cell positioning and cell‐matrix reorganization.
Panic in Australia
Authors: Burrows GD , Norman TR , Ellen SR , Maguire KP , Judd FK
Published: July 2002

Panic disorder is widespread in Australia, often in combination with other psychiatric conditions such as agoraphobia or major depression. Pharmacotherapy for panic disorder in Australia commenced with benzodiazepines, and later progressed to tricyclic antidepressants (TCAs) and monoamine oxidase inhibitors (MAOIs). More recently, treatment has moved towards use of the selective serotonin reuptake inhibitors (SSRIs), which are effective and better tolerated. Paroxetine is the first drug of this class to receive approval for treatment of panic disorder in Australia.
Correlation between 3D scanner image and MRI for tracking volume changes in head and neck cancer patients
Authors: Kim Jung‐in , Chung Joo‐Hyun , Kwon Ohyun , Min Park Jong , Wu Hong‐Gyun
Published: February 2021

Introduction

We investigated the correlation between optical surface imaging using a three‐dimensional (3D) scanner and magnetic resonance imaging (MRI) for suggesting feasibility in the clinical process of tracking volume changes in head and neck patients during radiation treatment.

Methods

Ten patients were divided into two groups depending on the location of their tumor (i.e., right or left side). With weekly imaging data, the change in volume based on MRI was evaluated during the treatment course. Four volumes of interest (VOIs) were calculated on the 3D surface image of the facial and cervical areas using an optical 3D scanner, and the correlation between volumetric parameters were analyzed.

Results

The target volume changed significantly overall for both groups. The changes parotid volume reduced by up to 3.8% and 28.0% for groups A (right side) and B (left side), respectively. In Group A, VOI 1 on the facial area and VOI 3 on the cervical area decreased gradually during the treatment course by up to 3.3% and 10.7%, respectively. In Group B, only VOI 4 decreased gradually during the treatment course and reduced by up to 9.2%. In group A, the change in target volume correlated strongly with right‐side parotid, VOI 1, and VOI 3, respectively. The parotid also showed strong correlations with VOIs (P < 0.01). The weight loss was strongly correlated with either PTV or parotid without statistical significance (P > 0.05). In group B (left side), the change in target volume correlated strongly with each volumetric parameter, including weight loss. For individual patient, PTV showed more correlation with VOIs on the cervical area than VOIs on the facial area.

Conclusions

An optical 3D scanner can be applied to track changes in volume without radiation exposure during treatment and the optical surface image correlated with MRI.
The prevalence effect in fingerprint identification: Match and non‐match base‐rates impact misses and false alarms
Authors: Growns Bethany , Kukucka Jeff
Published: February 2021

The prevalence effect is a phenomenon whereby target prevalence impacts performance in visual search (e.g., baggage screening) and visual comparison (e.g., face‐matching) tasks – people more often 'miss' infrequent target stimuli. The current study investigated prevalence effects in fingerprint identification – an important visual comparison task used in criminal investigations. Participants (N = 287) judged 100 fingerprint pairs where the prevalence of match trials was either 10% (low), 50% (equal), or 90% (high), and half received trial‐level feedback on their performance. As predicted, low match prevalence increased errors on match trials (i.e., misses), whereas high match prevalence errors on non‐match trials (i.e., false alarms) – but only when participants received feedback. These effects were largely driven by changes in bias (C), rather than sensitivity (d’). These results suggest that the combination of feedback and match prevalence can impact the types of errors that fingerprint examiners may make in practice.
Testing the seductive details effect: Does the format or the amount of seductive details matter?
Authors: Wang Zhe , Ardasheva Yuliya , Carbonneau Kira , Liu Qinglong
Published: February 2021

A body of research indicates that the inclusion of seductive details in instructional materials negatively impacts learning. However, there is scant research that examines the format and the amount of seductive details as potential moderating factors across multiple learning outcomes. In two studies, one focused on seductive pictures and one on seductive text, we examined whether the amount of seductive details influenced learning performance on several outcomes. Experiment 1 participants were 88 middle school students (68% female,Mage= 17.45 years) randomly assigned to no‐seductive‐images (n= 30), single‐seductive‐image‐per‐screen (n= 30), and multiple‐seductive‐images‐per‐screen (n= 28) conditions. In Experiment 2 focused on seductive text, participants were 93 middle school students (61% female;Mage= 17.26 years) randomly assigned to no‐seductive‐details (n= 33), short‐seductive‐details (n= 33), and long‐seductive‐details (n= 30) conditions. Across experiments, we collected data on situational interest, cognitive load, retention, and transfer as well as judgments of learning, distraction, and learning‐related emotions. Findings showed that students learning with longer seductive text (but not multiple images) significantly outperformed those learning with shorter‐text or no‐seductive‐details in terms of transfer. This study highlights the importance of exploring seductive details in relation to both the format of presentation and the amount of seductive details.
Mechanical Alloying of Immiscible Metallic Systems: Process, Microstructure, and Mechanism
Authors: Shuai Cijun , He Chongxian , Peng Shuping , Qi Fangwei , Wang Guoyong , Min Anjie , Yang Wenjing , Wang Weiguo
Published: February 2021

Immiscible metallic systems provide new opportunities for tailoring material properties due to their unique microstructure. However, they are immiscible in the liquid state, or separate into incompatible liquid phase during the cooling process, making it difficult to obtain their alloys or phases. Mechanical alloying is a solid‐state processing route, whose basic principle is to utilize mechanical impact to make materials suffer cyclic deforming, fracturing, and welding. It reduces the energy barrier and provides pathways of atom diffusion, achieving atomic‐level alloying in solid‐state. Notably, mechanical alloying does not undergo the cooling process from liquid to solid phase, which can avoid the solute separation. This article discusses the mechanical alloying process, microstructure, and mechanism of immiscible metallic systems. It focuses on the alloying principles, including solid solutions, intermetallic compounds, nanocrystalline or amorphous alloys. In addition, the effects of process parameters, including rotation speed, milling time, and ball‐to‐powder weight ratio, on microstructure and phase constitution are comprehensively reviewed. Some useful suggestions regarding the preparation of immiscible metallic systems are also put forward for future works.
Inhibition of Manganese Dissolution in Mn2O3 Cathode with Controllable Ni2+ Incorporation for High‐Performance Zinc Ion Battery
Authors: Zhang Dongdong , Cao Jin , Zhang Xinyu , Insin Numpon , Wang Shanmin , Han Jiantao , Zhao Yusheng , Qin Jiaqian , Huang Yunhui
Published: February 2021

Manganese‐based materials are considered potential cathode materials for aqueous zinc ion batteries (ZIBs). However, the dissolution of manganese leading to an abrupt decline of capacity and the sluggish electrochemical reaction kinetics are still the main bottlenecks restricting their further development. Herein, a NiMn‐layered double hydroxide‐derived Ni‐doped Mn2O3 (NM) is developed to suppress the dissolution of manganese. The incorporation of Ni2+ can promote electronic rearrangement and enhance the conductivity, ultimately improving the reaction kinetics and electrochemical performance of the NM. Moreover, the doped Ni2+ can effectively stabilize the MnO bond of Mn2O3 by reducing the formation energy. In addition, the storage mechanism based on the simultaneous insertion and transformation of H+ and Zn2+ is demonstrated. Interestingly, the Ni‐doped Mn2O3 shows a high specific capacity of 252 mAh g–1 (0.1 A g–1), three times more than the pure Mn2O3 (72 mAh g–1). The capacity retention (≈85.6% over 2500 cycles at 1.0 A g–1) is also more excellent when comparing with the Mn2O3 cathode (≈49.7%). Significantly, an ultra‐high energy density of 327.6 Wh kg–1 has been achieved using Ni‐doped Mn2O3 cathode, which suggests that the synergistic effect of manganese and other transition metal ions provide a promising strategy for future development of ZIBs.
Supraparticles for Sustainability
Authors: Wintzheimer Susanne , Reichstein Jakob , Groppe Philipp , Wolf Andreas , Fett Bastian , Zhou Huanhuan , Pujales‐Paradela Rosa , Miller Franziska , Müssig Stephan , Wenderoth Sarah , Mandel Karl
Published: February 2021

The indispensable transformation to a (more) sustainable human society on this planet heavily relies on innovative technologies and advanced materials. The merits of nanoparticles (NPs) in this context are demonstrated widely during the last decades. Yet, it is believed that the impact of particle‐based nanomaterials to sustainability can be even further enhanced: taking NPs as building blocks enables the creation of more complex entities, so‐called supraparticles (SPs). Due to their evolving phenomena coupling, emergence, and colocalization, SPs enable completely new material functionalities. These new functionalities in SPs can be utilized to render six fields, essential to human life as it is conceived, more sustainable. These fields, selected based on an entropy‐rate‐related definition of sustainability, are as follows: 1) purification technologies and 2) agricultural delivery systems secure humans “fundamental needs.” 3) Energy storage and conversion, as well as 4) catalysis enable the “basic comfort.” 5) Extending materials lifetime and 6) bringing materials back in use ensure sustaining “modern life comfort.” In this review article, a perspective is provided on why and how the properties of SPs, and not simply properties of individual NPs or conventional bulk materials, may grant attractive alternative pathways in these fields.
Guided Mid‐IR and Near‐IR Light within a Hybrid Hyperbolic‐Material/Silicon Waveguide Heterostructure
Authors: He Mingze , Halimi Sami I. , Folland Thomas G. , Sunku Sai S. , Liu Song , Edgar James H. , Basov D. N. , Weiss Sharon M. , Caldwell Joshua D.
Published: February 2021

Silicon waveguides have enabled large‐scale manipulation and processing of near‐infrared optical signals on chip. Yet, expanding the bandwidth of guided waves to other frequencies will further increase the functionality of silicon as a photonics platform. Frequency multiplexing by integrating additional architectures is one approach to the problem, but this is challenging to design and integrate within the existing form factor due to scaling with the free‐space wavelength. This paper demonstrates that a hexagonal boron nitride (hBN)/silicon hybrid waveguide can simultaneously enable dual‐band operation at both mid‐infrared (6.5–7.0 µm) and telecom (1.55 µm) frequencies, respectively. The device is realized via the lithography‐free transfer of hBN onto a silicon waveguide, maintaining near‐infrared operation. In addition, mid‐infrared waveguiding of the hyperbolic phonon polaritons (HPhPs) supported in hBN is induced by the index contrast between the silicon waveguide and the surrounding air underneath the hBN, thereby eliminating the need for deleterious etching of the hyperbolic medium. The behavior of HPhP waveguiding in both straight and curved trajectories is validated within an analytical waveguide theoretical framework. This exemplifies a generalizable approach based on integrating hyperbolic media with silicon photonics for realizing frequency multiplexing in on‐chip photonic systems.
2D Copper Tetrahydroxyquinone Conductive Metal–Organic Framework for Selective CO2 Electrocatalysis at Low Overpotentials
Authors: Majidi Leily , Ahmadiparidari Alireza , Shan Nannan , Misal Saurabh N. , Kumar Khagesh , Huang Zhehao , Rastegar Sina , Hemmat Zahra , Zou Xiaodong , Zapol Peter , Cabana Jordi , Curtiss Larry A. , Salehi‐Khojin Amin
Published: February 2021

Metal–organic frameworks (MOFs) are promising materials for electrocatalysis; however, lack of electrical conductivity in the majority of existing MOFs limits their effective utilization in the field. Herein, an excellent catalytic activity of a 2D copper (Cu)‐based conductive MOF, copper tetrahydroxyquinone (CuTHQ), is reported for aqueous CO2 reduction reaction (CO2RR) at low overpotentials. It is revealed that CuTHQ nanoflakes (NFs) with an average lateral size of 140 nm exhibit a negligible overpotential of 16 mV for the activation of this reaction, a high current density of ≈173 mA cm−2 at −0.45 V versus RHE, an average Faradaic efficiency (F.E.) of ≈91% toward CO production, and a remarkable turnover frequency as high as ≈20.82 s−1. In the low overpotential range, the obtained CO formation current density is more than 35 and 25 times higher compared to state‐of‐the‐art MOF and MOF‐derived catalysts, respectively. The operando Cu K‐edge X‐ray absorption near edge spectroscopy and density functional theory calculations reveal the existence of reduced Cu (Cu+) during CO2RR which reversibly returns to Cu2+ after the reaction. The outstanding CO2 catalytic functionality of conductive MOFs (c‐MOFs) can open a way toward high‐energy‐density electrochemical systems.
Translocation of DNA through Ultrathin Nanoslits
Authors: Yang Wayne , Radha Boya , Choudhary Adnan , You Yi , Mettela Gangaiah , Geim Andre K. , Aksimentiev Aleksei , Keerthi Ashok , Dekker Cees
Published: February 2021

2D nanoslit devices, where two crystals with atomically flat surfaces are separated by only a few nanometers, have attracted considerable attention because their tunable control over the confinement allows for the discovery of unusual transport behavior of gas, water, and ions. Here, the passage of double‐stranded DNA molecules is studied through nanoslits fabricated from exfoliated 2D materials, such as graphene or hexagonal boron nitride, and the DNA polymer behavior is examined in this tight confinement. Two types of events are observed in the ionic current: long current blockades that signal DNA translocation and short spikes where DNA enters the slits but withdraws. DNA translocation events exhibit three distinct phases in their current‐blockade traces—loading, translation, and exit. Coarse‐grained molecular dynamics simulation allows the different polymer configurations of these phases to be identified. DNA molecules, including folds and knots in their polymer structure, are observed to slide through the slits with near‐uniform velocity without noticeable frictional interactions of DNA with the confining graphene surfaces. It is anticipated that this new class of 2D‐nanoslit devices will provide unique ways to study polymer physics and enable lab‐on‐a‐chip biotechnology.
Pressure Sensitivity of Charge Conduction Through the Interface Between a Metal Oxide Nanocrystallite and Graphene
Authors: Hossein‐Babaei Faramarz , Yousefiazari Ehsan , Ghalamboran Milad
Published: February 2021

Highly sensitive, micron‐size, lightweight, and cost‐effective pressure sensors and pressure sensor arrays are in demand for varieties of sonic, biomedical, tactile, and wearable microelectronic applications. Here, the electrical conduction through the interface between a metal oxide semiconductor nanocrystallite and graphene (Gr) formed in O‐rich conditions is shown to be highly pressure sensitive, and a novel class of pressure sensors operating based on the electronic features of heterointerfaces is introduced. First‐principle studies on ZnO/Gr interface attribute the observed pressure sensitivity to the spontaneous formation of a sparse layer of oxygen at the O‐terminated ZnO/Gr interface. Strained by the external force, this layer controls the electron conduction through the junction. In the reduced oxygen conditions, the formation of a stable and pressure insensitive Zn‐terminated ZnO/Gr junction is predicted, which reversibly transforms to the former upon annealing in air at 300 °C. The presented results concerning the spontaneity of adsorbing oxygen species to the O‐terminated metal oxide/Gr junctions are anticipated to assist understanding and engineering of the piezoresistivity and chemiresistivity in the metal oxide‐Gr composites.
The Synergy of Plasmonic Enhancement and Hot‐Electron Effect on CsPbBr3 Nanosheets Photodetector
Authors: Dong Yuhui , Xu Leimeng , Zhao Yongli , Wang Shalong , Song Jizhong , Zou Yousheng , Zeng Haibo
Published: February 2021

Nowadays, 2D inorganic cesium lead halide perovskites (IHPs) based photodetectors (PDs) have shown great potential due to the excellent optoelectronic properties. However, most of them only focus on improving carrier transmission and not on synergistic increase in light absorption efficiency or vice versa, limiting the total number of photon‐generated carriers. Here, an effective and general strategy is demonstrated, combining the synergy of plasmonic enhancement of light absorption and hot‐electron effect. The responsivity and external quantum efficiency (EQE) of this planar PD improves obviously, which is more than 20‐fold of the pristine devices. Furthermore, a wide linear dynamic range (LDR) of 120 dB is realized, and both response speed and operating frequency are simultaneously improved. The results present the potential use of synergistic effect for PDs, and provide a promising strategy for improving performance of perovskite optoelectronic devices.
Step by Step Bisacrificial Templates Growth of Bimetallic Sulfide QDs‐Attached MOF Nanosheets for Nonlinear Optical Limiting
Authors: Zhu Yin‐Di , Kang Yao , Gu Zhi‐Gang , Zhang Jian
Published: February 2021

Here, the authors first report a bimetallic sulfide quantum dots (QDs)‐attached metal–organic framework (MOF) nanosheets‐based film from bisacrificial templates. By using a step by step bisacrificial templates strategy, MOF CuBDC precursors (BDC = 1,4‐benzenedicarboxylate) and chalcogenidometalates as the templates can successfully in‐situ assemble Cu2SnS3 (CTS) QDs‐attached CuBDC nanosheets on the functionalized substrate (CTS @ CuBDC film). The obtained CTS QDs possess a uniform size with ≈6.2 nm and are homogeneously dispersed on MOF nanosheets, which results in an improvement of conductivity and represents a semiconductive composite film for optical application. A Z‐scan study under the excitation of a 532 nm laser shows that the CTS @ CuBDC film possesses strong optical limiting (OL) behavior and very low OL thresholds (0.92 J cm−2) as well as large third‐order nonlinear susceptibility (1.9 × 10−6 esu). This work suggests that the step by step bisacrificial templates method is a fascinating and feasible strategy to prepare metal sulfide QDs dispersed MOF hybrid materials, and provides a promising potential candidate for nonlinear optical applications.
Immunogenic Cell Death Inducing Fluorinated Mitochondria‐Disrupting Helical Polypeptide Synergizes with PD‐L1 Immune Checkpoint Blockade
Authors: Jeong Seong Dong , Jung Bo‐Kyeong , Ahn Hyo Min , Lee DaeYong , Ha JongHoon , Noh Ilkoo , Yun Chae‐Ok , Kim Yeu‐Chun
Published: February 2021

Immunogenic cell death (ICD) is distinguished by the release of tumor‐associated antigens (TAAs) and danger‐associated molecular patterns (DAMPs). This cell death has been studied in the field of cancer immunotherapy due to the ability of ICD to induce antitumor immunity. Herein, endoplasmic reticulum (ER) stress‐mediated ICD inducing fluorinated mitochondria‐disrupting helical polypeptides (MDHPs) are reported. The fluorination of the polypeptide provides a high helical structure and potent anticancer ability. This helical polypeptide destabilizes the mitochondrial outer membrane, leading to the overproduction of intracellular reactive oxygen species (ROS) and apoptosis. In addition, this oxidative stress triggers ER stress‐mediated ICD. The in vivo results show that cotreatment of fluorinated MDHP and antiprogrammed death‐ligand 1 antibodies (αPD‐L1) significantly regresses tumor growth and prevents metastasis to the lungs by activating the cytotoxic T cell response and alleviating the immunosuppressive tumor microenvironment. These results indicate that fluorinated MDHP synergizes with the immune checkpoint blockade therapy to eliminate established tumors and to elicit antitumor immune responses.
Highly Selective Separation Intermediate‐Size Anionic Pollutants from Smaller and Larger Analogs via Thermodynamically and Kinetically Cooperative‐Controlled Crystallization
Authors: Mi Yongsheng , Zhao Chaofeng , Xue Shaomin , Ding Ning , Du Yao , Su Hui , Li Shenghua , Pang Siping
Published: February 2021

Selective separation of organic species, particularly that of intermediate‐size ones from their analogs, remains challenging because of their similar structures and properties. Here, a novel strategy is presented, cooperatively (thermodynamically and kinetically) controlled crystallization for the highly selective separation of intermediate‐size anionic pollutants from their analogs in water through one‐pot construction of cationic metal‐organic frameworks (CMOFs) with higher stabilities and faster crystallization, which are based on the target anions as charge‐balancing anions. 4,4′‐azo‐triazole and Cu2+ are chosen as suitable ligand and metal ion for CMOF construction because they can form stronger intermolecular interaction with p‐toluenesulfonate anion (Tsˉ) compared to its analogs. For this combination, a condition is established, under which the crystallization rate of a Tsˉ‐based CMOF is remarkably high while those of analog‐based CMOFs are almost zero. As a result, the faster crystallization and higher stability cooperatively endow the cationic framework with a close‐to‐100% selectivity for Tsˉ over its analogs in two‐component mixtures, and this preference is retained in a practical mixture containing more than seven competing (analogs and inorganic) anions. The nature of the free Tsˉ anion in the cationic framework also allows the resultant CMOF to be recyclable via anion exchange.
Lifetime‐Engineered Carbon Nanodots for Time Division Duplexing
Authors: Liang Ya‐Chuan , Liu Kai‐Kai , Wu Xue‐Ying , Lou Qing , Sui Lai‐Zhi , Dong Lin , Yuan Kai‐Jun , Shan Chong‐Xin
Published: February 2021

Optical multiplexing attracts considerable attention in the field of information encryption, optical probe, and time‐resolved bioimaging. However, the optical multiplexing based on rare‐earth nanoparticles suffers from heavy metal elements and relatively short lifetimes; sophisticated facilities are thus needed. Herein, time division duplexing based on eco‐friendly carbon nanodots (CNDs) with manipulative luminescence lifetimes is demonstrated. In a single green color emission channel, the luminescence lifetimes of the CNDs can be manipulated from nanosecond level to second level by introducing water, while the lifetime of the CNDs confined by a silica shell stays. Time division duplexing based on the CNDs and CNDs@silica with distinct lifetimes is realized and spatio‐temporal overlapping information is thus resolved. High‐level information encryption using the time division duplexing technology is realized. This work may promise the potential applications of CNDs in multi‐lifetime channels biological imaging, high‐density information storage, and anti‐counterfeiting.
Schottky Junctions with Bi Cocatalyst for Taming Aqueous Phase N2 Reduction toward Enhanced Solar Ammonia Production
Authors: Huang Yewei , Zhu Yisong , Chen Shuijiao , Xie Xiuqiang , Wu Zhenjun , Zhang Nan
Published: February 2021

Solar‐powered N2 reduction in aqueous solution is becoming a research hotspot for ammonia production. Schottky junctions at the metal/semiconductor interface have been effective to build up a one‐way channel for the delivery of photogenerated electrons toward photoredox reactions. However, their applications for enhancing the aqueous phase reduction of N2 to ammonia have been bottlenecked by the difficulty of N2 activation and the competing H2 evolution reaction (HER) at the metal surface. Herein, the application of Bi with low HER activity as a robust cocatalyst for constructing Schottky‐junction photocatalysts toward N2 reduction to ammonia is reported. The introduction of Bi not only boosts the interfacial electron transfer from excited photocatalysts due to the built‐in Schottky‐junction effect at the Bi/semiconductor interface but also synchronously facilitates the on‐site N2 adsorption and activation toward solar ammonia production. The unidirectional charge transfer to the active site of Bi significantly promotes the photocatalytic N2‐to‐ammonia conversion efficiency by 65 times for BiOBr. In addition, utilizing Bi to enhance the photocatalytic ammonia production can be extended to other semiconductor systems. This work is expected to unlock the promise of engineering Schottky junctions toward high‐efficiency solar N2‐to‐ammonia conversion in aqueous phase.
Magneto‐Based Synergetic Therapy for Implant‐Associated Infections via Biofilm Disruption and Innate Immunity Regulation
Authors: Wang Jiaxing , Wang Lingtian , Pan Jiong , Zhao Jinhui , Tang Jin , Jiang Dajun , Hu Ping , Jia Weitao , Shi Jianlin
Published: February 2021

Implant‐associated infections (IAIs) are a common cause of orthopedic surgery failure due to microbial biofilm‐induced antibiotic‐resistance and innate immune inactivation. Thus, the destruction of microbial biofilm plays a key role in reducing IAIs. Herein, first, a magneto‐based synergetic therapy (MST) is proposed and demonstrated against IAIs based on biofilm destruction. Under an alternating magnetic field (AMF), CoFe2O4@MnFe2O4 nanoparticles (MNPs), with a rather strong magnetic hyperthermal capacity, can generate sufficient thermal effect to cause dense biofilm dispersal. Loosened biofilms provide channels through which nitrosothiol‐coated MNPs (MNP‐SNOs) can penetrate. Subsequently, thermosensitive nitrosothiols rapidly release nitric oxide (NO) inside biofilms, thus efficiently killing sessile bacteria under the magnetothermal effect of MNPs. More importantly, MNP‐SNOs can trigger macrophage‐related immunity to prevent the relapse of IAIs by exposing the infected foci to a consistent innate immunomodulatory effect. The notable anti‐infection effect of this nanoplatform is also confirmed in a rat IAI model. This work presents the promising potential of combining magnetothermal therapy with immunotherapy, for the effective and durable control and elimination of IAIs.
Advanced Development Strategy of Nano Catalyst and DFT Calculations for Direct Synthesis of Hydrogen Peroxide
Authors: Han Geun‐Ho , Lee Seok‐Ho , Hwang Seong‐Yeon , Lee Kwan‐Young
Published: February 2021

Hydrogen peroxide is a simple oxidizing agent. Its environmental benignness and effectiveness have led to a continuous increase in its use and production. Anthraquinone autoxidation (the AO process) is generally used to manufacture hydrogen peroxide (H2O2); however, this complex multi‐stage process releases large amounts of organic solvent into the environment and requires significant energy to operate. As a green and energy‐efficient production method, the direct synthesis of hydrogen peroxide (DSHP) from molecular hydrogen and oxygen can overcome the disadvantages of the AO process. However, DSHP has remained challenging until recently as severe mass‐transfer limitations and unavoidable side reactions result in insufficient selectivity for H2O2. However, beyond the conventional development methods for catalysts, recent advances in chemical and engineering fields can appreciably assist in the discovery of a “dream catalyst” for DSHP; high‐end computational methods and the facile surface‐controllable syntheses of nanocatalysts. This review addresses how a combination of density functional theory (DFT) calculations and nanocatalyst synthesis technologies lead to the development of high‐performance catalysts for DSHP, and provides guidelines on efficient methodologies for the development of catalysts through the use of cutting edge technologies.
Origin of Hole Transport in Small Molecule Dilute Donor Solar Cells
Authors: Kaiser Waldemar , Murthy Lakshmi N. S. , Chung Chin‐Lung , Wong Ken‐Tsung , Hsu Julia W.P. , Gagliardi Alessio
Published: February 2021

Dilute donor organic solar cells (OSCs) are a promising technology to circumvent the trade‐off between open‐circuit voltage (Voc) and short‐circuit current density (Jsc). The origin of hole transport in OSCs with donor concentrations below the percolation threshold is diversely discussed in the community. Herein, both hole back transfer and long‐range hopping (tunneling) are analyzed as possible mechanisms of photocurrent in small molecule dilute donor OSCs using kinetic Monte Carlo (kMC) simulations. In contrast to previous kMC studies, the driving force for exciton dissociation is accounted for. As a study system, nitrogen‐bridged terthiophene (NBTT) molecules in a [6,6]‐phenyl‐C70‐butyric acid methyl ester (PC71BM) matrix are investigated. The simulations show that hole back transfer from the small molecule donor to the fullerene matrix explains the measured concentration dependences of the photocurrents as well as the Jsc dependence on the light intensity for donor concentrations below 5 wt%. For 5 wt%, distances between NBTT molecules decrease to reasonable ranges that long‐range hopping or tunneling cannot be discounted. Compared with polymer donors, larger hole localization is observed. The results emphasize that the barrier for hole back transfer is not only due to the highest occupied molecular orbital (HOMO) offset, but also by hole localization.
Photocatalytic Plasmon‐Enhanced Nitrogen Reduction to Ammonia
Authors: Monyoncho Evans A. , Dasog Mita
Published: February 2021

Nitrogen reduction to ammonia under ambient conditions is an emerging area of research sparked by the increasing concerns over climate change which is driving the efforts to find alternatives to energy‐intensive Haber–Bosch process. Ammonia is a critical component in the manufacturing of fertilizers and is required to support the global food supply. It can also be used as a fuel source to generate electricity. Many strategies have been used to drive nitrogen reduction under milder conditions including incorporation of plasmonic nanomaterials. The ability of plasmonic nanomaterials to strongly interact with light, resulting in near‐field enhancement, hot charge‐carrier generation and injection, increase in local temperature, has made them attractive candidates for catalysis. This review provides a comprehensive survey of recent developments in photocatalytic, plasmon‐enhanced nitrogen conversion to ammonia and the proposed mechanisms for the increased catalytic activity. A brief outlook on the current challenges and future directions is also provided.
Active optical sensor measurements and weather variables for predicting winter wheat yield
Authors: Aula Lawrence , Omara Peter , Nambi Eva , Oyebiyi Fikayo B. , Dhillon Jagmandeep , Eickhoff Elizabeth , Carpenter Jonathan , Raun William R.
Published: February 2021

Accurate winter wheat (Triticum aestivum L.) grain yield prediction is vital for improving N management decisions. Currently, most N optimization algorithms use in‐season estimated yield (INSEY) as a sole variable for predicting grain yield potential (YP). Although evidence suggests that this works, the yield prediction accuracy could be further improved by including other predictors in the model. The objective of this work was to evaluate INSEY, pre‐plant N rate, total rainfall, and average air temperature from September to December as predictors of winter wheat YP. An 8‐yr (2012–2019) data set for grain yield was obtained from Experiment 502, Lahoma, OK. The experiment was designed as a randomized complete block with four replications and N applied at 0, 45, 67, 90, and 112 kg ha–1. Weather data was obtained from the Oklahoma Mesonet (http://mesonet.org). The data were analyzed using R statistical computing platform. The best model was selected using least absolute shrinkage and selection operator. Root mean square error (RMSE) was obtained using k‐fold cross‐validation. The model selection algorithm produced the full model as the best model for yield prediction with an R2 of .79 and RMSE of 0.54 Mg ha–1. The best one‐variable model – as expected – used INSEY as the predictor and had the highest RMSE of 0.72 Mg ha–1 and an R2 of .62. Mid‐season YP prediction accuracy could be improved by including pre‐plant N rate, mean air temperature, and total rainfall from September to December in a model already containing INSEY.
Investigation of the influence of pancreatic surgery on new‐onset and persistent diabetes mellitus
Authors: Yamada Daisaku , Takahashi Hidenori , Asukai Kei , Hasegawa Shinichiro , Wada Hiroshi , Matsuda Chu , Yasui Masayoshi , Omori Takeshi , Miyata Hiroshi , Sakon Masato
Published: February 2021

Aim

The management of diabetes mellitus (DM) after pancreatic surgery is a long‐standing issue. We aimed to investigate DM concerning pancreatic surgery, including new onset diabetes mellitus (NODM), DM resolution, and the change in insulin excretion before/after pancreatic surgery.

Methods

We retrospectively investigated three different cohorts (total 403 patients) undergoing pancreatectomy. Of those, 275 patients without preoperative DM were investigated for the risk factors of NODM. Fifty‐four patients without preoperative DM of the other cohort were assessed for pre/postoperative 24‐hour urinary C‐peptide excretion (24‐hr CPR). To evaluate the influence of pancreatic surgery on DM treatment in patients with preoperative DM, 74 patients were investigated. In all those patients, the pancreatic volume in pre/postoperative images was assessed to estimate the resected pancreatic volume.

Results

NODM was observed in 60 patients (21%), and a lower ratio of remnant pancreatic volume (RRPV) was the only significant risk factor for NODM. Postoperative 24‐hr CPR was significantly associated with two factors, RRPV and preoperative 24‐hr CPR. Nine of 74 patients with preoperative DM achieved DM resolution after pancreatic surgery, and the presence of gastrointestinal anastomosis was a significant preferable factor for DM resolution.

Conclusions

Considering the management of DM after surgery, both predicting the postoperative pancreatic volume and the presence of gastrointestinal reconstruction are significant. We concluded that the combined assessment of the predicted remnant pancreatic volume and the preoperative 24‐hr CPR value is useful to predict the postoperative pancreatic function.
Working near a supervised injection facility: A qualitative study of perspectives of firefighter‐emergency medical responders
Authors: Pennington Michelle L. , Dupree Jessica , Coe Elizabeth , Ostiguy William , Kimbrel Nathan A. , Meyer Eric C. , Gulliver Suzy B.
Published: February 2021

Background

While firefighter‐emergency medical responders (FF‐EMR) are important stakeholders in cities considering the implementation of a supervised injection facility (SIF), there is little information on perspectives of first responders who serve these communities. The aim of the present study was to identify FF‐EMR perspectives on working near a SIF.

Methods

FF‐EMRs from Vancouver Fire and Rescue Services completed an online survey that queried participant perspectives on working near a SIF.

Results

Four main themes were identified: positive effects, negative effects, duration of assignment, and sense of duty. Similar percentages of first responders reported positive (22.2%) and negative aspects (25.9%) of working near the SIF, while some (18.5%) indicated preference for a short‐term assignment to the SIF area. FF‐EMRs most commonly described a sense of duty (35.2%).

Conclusions

To our knowledge, our study is the first to identify FF‐EMR perspectives related to work near a SIF. Perspectives and concerns of first responders should be considered in policy debates about implementation of new SIFs to guarantee an adequately‐prepared first responder workforce.
COVID‐19 deaths by occupation, Massachusetts, March 1–July 31, 2020
Authors: Hawkins Devan , Davis Letitia , Kriebel David
Published: February 2021

Background

Exposure to COVID‐19 is more likely among certain occupations compared with others. This descriptive study seeks to explore occupational differences in mortality due to COVID‐19 among workers in Massachusetts.

Methods

Death certificates of those who died from COVID‐19 in Massachusetts between March 1 and July 31, 2020 were collected. Occupational information was coded and age‐adjusted mortality rates were calculated according to occupation.

Results

There were 555 deaths among MA residents of age 16–64, with usable occupation information, resulting in an age‐adjusted mortality rate of 16.4 per 100,000 workers. Workers in 11 occupational groups including healthcare support and transportation and material moving had mortality rates higher than that for workers overall. Hispanic and Black workers had age‐adjusted mortality rates more than four times higher than that for White workers overall and also had higher rates than Whites within high‐risk occupation groups.

Conclusion

Efforts should be made to protect workers in high‐risk occupations identified in this report from COVID‐19 exposure.
Common pathogenesis for sirenomelia, OEIS complex, limb‐body wall defect, and other malformations of caudal structures
Authors: Stevenson Roger E.
Published: February 2021

Decades of clinical, pathological, and epidemiological study and the recent application of advanced microarray and gene sequencing technologies have led to an understanding of the causes and pathogenesis of most recognized patterns of malformation. Still, there remain a number of patterns of malformation whose pathogenesis has not been established. Six such patterns of malformation are sirenomelia, VACTERL association, OEIS complex, limb‐body wall defect (LBWD), urorectal septum malformation (URSM) sequence, and MURCS association, all of which predominantly affect caudal structures. On the basis of the overlap of the component malformations, the co‐occurrence in individual fetuses, and the findings on fetal examination, a common pathogenesis is proposed for these patterns of malformation. The presence of a single artery in the umbilical cord provides a visible clue to the pathogenesis of all cases of sirenomelia and 30%–50% of cases of VACTERL association, OEIS complex, URSM sequence, and LBWD. The single artery is formed by a coalescence of arteries that supply the yolk sac, arises from the descending aorta high in the abdominal cavity, and redirects blood flow from the developing caudal structures of the embryo to the placenta. This phenomenon during embryogenesis is termed vitelline vascular steal.