bluuebunny/crossref_metadata_2025 huggingface dataset:
Ferritin Oxidation in Vitro: Implication of Iron Release and Degradation by the 20S Proteasome
Authors: Rudeck M. , Volk T. , Sitte N. , Grune T.
Published: July 2002

Ferritin, the major iron storage protein in mammalian cells, was treated with various concentrations of different oxidants: xanthine/xanthine oxidase, Sin‐1 (3‐morpholinosydnonimine, purchased from Alexis, Grunberg, Germany), DEA‐NO (Diethylamine NONOate, purchased from Calblochem‐Novabiochem, Schwalbach, Germany), and hydrogen peroxide. The proteolytic susceptibility towards the isolated 20S proteasome of untreated ferritin and oxidized ferritin was measured in parallel with the iron liberated by these oxidants. With increasing hydrogen peroxide, Sin‐1, and xanthine oxidase concentrations, the measured proteasomal degradation of ferritin also increased. At higher oxidant concentrations, however, the proteolytic susceptibility began to decrease. The oxidation of ferritin by DEA‐NO was accompanied by a lesser increase of proteolytic susceptibility in comparison with the effects of the other oxidants. Addition of DEA‐NO to Sin‐1 suppressed the increase in proteolytic susceptibility of ferritin, whereas adding xanthine/xanthine oxidase had no additional effect. Iron was liberated readily from ferritin as a result of the oxidation process, although the increase in proteolytic susceptibility was not always correlated to the iron release. In fact, the degradation of oxidatively damaged ferritin was not accompanied by a further increase of free iron. Therefore, we conclude that the proteasome is a secondary antioxidative defense system that degrades only nonfunctional ferritin.
Vid24p, a Novel Protein Localized to the Fructose-1,6-bisphosphatase–containing Vesicles, Regulates Targeting of Fructose-1,6-bisphosphatase from the Vesicles to the Vacuole for Degradation
Authors: Chiang Meng-Chieh , Chiang Hui-Ling
Published: July 2002

Glucose regulates the degradation of the key gluconeogenic enzyme, fructose-1,6-bisphosphatase (FBPase), in Saccharomyces cerevisiae. FBPase is targeted from the cytosol to a novel type of vesicle, and then to the vacuole for degradation when yeast cells are transferred from medium containing poor carbon sources to fresh glucose. To identify proteins involved in the FBPase degradation pathway, we cloned our first VID (vacuolar import and degradation) gene. The VID24 gene was identified by complementation of the FBPase degradation defect of the vid24-1 mutant. Vid24p is a novel protein of 41 kD and is synthesized in response to glucose. Vid24p is localized to the FBPase-containing vesicles as a peripheral membrane protein. In the absence of functional Vid24p, FBPase accumulates in the vesicles and fails to move to the vacuole, suggesting that Vid24p regulates FBPase targeting from the vesicles to the vacuole. FBPase sequestration into the vesicles is not affected in the vid24-1 mutant, indicating that Vid24p acts after FBPase sequestration into the vesicles has occurred. Vid24p is the first protein identified that marks the FBPase-containing vesicles and plays a critical role in delivering FBPase from the vesicles to the vacuole for degradation.
Enhanced Secretion of Amylase from Exocrine Pancreas of Connexin32-deficient Mice
Authors: Chanson Marc , Fanjul Marjorie , Bosco Domenico , Nelles Eric , Suter Susanne , Willecke Klaus , Meda Paolo
Published: July 2002

To determine whether junctional communication between pancreatic acinar cells contributes to their secretory function in vivo, we have compared wild-type mice, which express the gap junctional proteins connexin32 (Cx32) and connexin26, to mice deficient for the Cx32 gene. Pancreatic acinar cells from Cx32 (−/−) mice failed to express Cx32 as evidenced by reverse transcription–PCR and immunolabeling and showed a marked reduction (4.8- and 25-fold, respectively) in the number and size of gap junctions. Dye transfer studies showed that the extent of intercellular communication was inhibited in Cx32 (−/−) acini. However, electrical coupling was detected by dual patch clamp recording in Cx32 (−/−) acinar cell pairs. Although wild-type and Cx32 (−/−) acini were similarly stimulated to release amylase by carbamylcholine, Cx32 (−/−) acini showed a twofold increase of their basal secretion. This effect was caused by an increase in the proportion of secreting acini, as detected with a reverse hemolytic plaque assay. Blood measurements further revealed that Cx32 (−/−) mice had elevated basal levels of circulating amylase. The results, which demonstrate an inverse relationship between the extent of acinar cell coupling and basal amylase secretion in vivo, support the view that the physiological recruitment of secretory acinar cells is regulated by gap junction mediated intercellular communication.
Neuroendocrine Synaptic Vesicles Are Formed In Vitro by Both Clathrin-dependent and Clathrin-independent Pathways
Authors: Shi Gongyi , Faúndez Victor , Roos Jack , Dell'Angelica Esteban C. , Kelly Regis B.
Published: July 2002

In the neuroendocrine cell line, PC12, synaptic vesicles can be generated from endosomes by a sorting and vesiculation process that requires the heterotetrameric adaptor protein AP3 and a small molecular weight GTPase of the ADP ribosylation factor (ARF) family. We have now discovered a second pathway that sorts the synaptic vesicle-associated membrane protein (VAMP) into similarly sized vesicles. For this pathway the plasma membrane is the precursor rather than endosomes. Both pathways require cytosol and ATP and are inhibited by GTPγS. The second pathway, however, uses AP2 instead of AP3 and is brefeldin A insensitive. The AP2-dependent pathway is inhibited by depletion of clathrin or by inhibitors of clathrin binding, whereas the AP3 pathway is not. The VAMP-containing, plasma membrane–derived vesicles can be readily separated on sucrose gradients from transferrin (Tf)-containing vesicles generated by incubating Tf-labeled plasma membrane preparations at 37°C. Dynamin- interacting proteins are required for the AP2-mediated vesiculation from the plasma membrane, but not from endosomes. Thus, VAMP is sorted into small vesicles by AP3 and ARF1 at endosomes and by AP2 and clathrin at the plasma membrane.
The J-related Segment of Tim44 Is Essential for Cell Viability: A Mutant Tim44 Remains in the Mitochondrial Import Site, but Inefficiently Recruits mtHsp70 and Impairs Protein Translocation
Authors: Merlin Alessio , Voos Wolfgang , Maarse Ammy C. , Meijer Michiel , Pfanner Nikolaus , Rassow Joachim
Published: July 2002

Tim44 is a protein of the mitochondrial inner membrane and serves as an adaptor protein for mtHsp70 that drives the import of preproteins in an ATP-dependent manner. In this study we have modified the interaction of Tim44 with mtHsp70 and characterized the consequences for protein translocation. By deletion of an 18-residue segment of Tim44 with limited similarity to J-proteins, the binding of Tim44 to mtHsp70 was weakened. We found that in the yeast Saccharomyces cerevisiae the deletion of this segment is lethal. To investigate the role of the 18-residue segment, we expressed Tim44Δ18 in addition to the endogenous wild-type Tim44. Tim44Δ18 is correctly targeted to mitochondria and assembles in the inner membrane import site. The coexpression of Tim44Δ18 together with wild-type Tim44, however, does not stimulate protein import, but reduces its efficiency. In particular, the promotion of unfolding of preproteins during translocation is inhibited. mtHsp70 is still able to bind to Tim44Δ18 in an ATP-regulated manner, but the efficiency of interaction is reduced. These results suggest that the J-related segment of Tim44 is needed for productive interaction with mtHsp70. The efficient cooperation of mtHsp70 with Tim44 facilitates the translocation of loosely folded preproteins and plays a crucial role in the import of preproteins which contain a tightly folded domain.
Nuclei and Microtubule Asters Stimulate Maturation/M Phase Promoting Factor (Mpf) Activation in Xenopus Eggs and Egg Cytoplasmic Extracts
Authors: Pérez-Mongiovi Daniel , Beckhelling Clare , Chang Patrick , Ford Christopher C. , Houliston Evelyn
Published: July 2002

Although maturation/M phase promoting factor (MPF) can activate autonomously in Xenopus egg cytoplasm, indirect evidence suggests that nuclei and centrosomes may focus activation within the cell. We have dissected the contribution of these structures to MPF activation in fertilized eggs and in egg fragments containing different combinations of nuclei, centrosomes, and microtubules by following the behavior of Cdc2 (the kinase component of MPF), the regulatory subunit cyclin B, and the activating phosphatase Cdc25. The absence of the entire nucleus–centrosome complex resulted in a marked delay in MPF activation, whereas the absence of the centrosome alone caused a lesser delay. Nocodazole treatment to depolymerize microtubules through first interphase had an effect equivalent to removing the centrosome. Furthermore, microinjection of isolated centrosomes into anucleate eggs promoted MPF activation and advanced the onset of surface contraction waves, which are close indicators of MPF activation and could be triggered by ectopic MPF injection. Finally, we were able to demonstrate stimulation of MPF activation by the nucleus–centriole complex in vitro, as low concentrations of isolated sperm nuclei advanced MPF activation in cycling cytoplasmic extracts. Together these results indicate that nuclei and microtubule asters can independently stimulate MPF activation and that they cooperate to enhance activation locally.
Short KIR Haplotypes in Pygmy Chimpanzee (Bonobo) Resemble the Conserved Framework of Diverse Human KIR Haplotypes
Authors: Rajalingam Raja , Hong Mei , Adams Erin J. , Shum Benny P. , Guethlein Lisbeth A. , Parham Peter
Published: July 2002

Some pygmy chimpanzees (also called Bonobos) give much simpler patterns of hybridization on Southern blotting with killer cell immunoglobulin-like receptor (KIR) cDNA probes than do either humans or common chimpanzees. Characterization of KIRs from pygmy chimpanzees having simple and complex banding patterns identified nine different KIRs, representing seven genes. Five of these genes have orthologs in the common chimpanzee, and three of them (KIRCI, KIR2DL4, and KIR2DL5) also have human orthologs. The remaining two genes are KIR3D paralogous to the human and common chimpanzee major histocompatibility complex A– and/or -B–specific KIRs. Within a pygmy chimpanzee family, KIR haplotypes were defined. Simple patterns on Southern blot were due to inheritance of “short” KIR haplotypes containing only three KIR genes, KIRCI, KIR2DL4, and KIR3D, each of which represents one of the three major KIR lineages. These three genes in pygmy chimpanzees or their corresponding genes in humans and common chimpanzees form the conserved “framework” common to all KIR haplotypes in these species and upon which haplotypic diversity is built. The fecundity and health of individual pygmy chimpanzees who are homozygotes for short KIR haplotypes attest to the viability of short KIR haplotypes, indicating that they can provide minimal, essential KIRs for the natural killer and T cells of the hominoid immune system.
Cytoplasmic Unsaturated Free Fatty Acids Inhibit Atp-Dependent Gating of the G Protein–Gated K+ Channel
Authors: Kim Donghee , Pleumsamran Apisate
Published: July 2002

This study reports the identification of an endogenous inhibitor of the G protein–gated (KACh) channel and its effect on the KACh channel kinetics. In the presence of acetylcholine in the pipette, KACh channels in inside-out atrial patches were activated by applying GTP to the cytoplasmic side of the membrane. In these patches, addition of physiological concentration of intracellular ATP (4 mM) upregulated KACh channel activity approximately fivefold and induced long-lived openings. However, such ATP-dependent gating is normally not observed in cell-attached patches, indicating that an endogenous substance that inhibits the ATP effect is present in the cell. We searched for such an inhibitor in the cell. ATP-dependent gating of the KACh channel was inhibited by the addition of the cytosolic fraction of rat atrial or brain tissues. The lipid component of the cytosolic fraction was found to contain the inhibitory activity. To identify the lipid inhibitor, we tested the effect of ∼40 different lipid molecules. Among the lipids tested, only unsaturated free fatty acids such as oleic, linoleic, and arachidonic acids (0.2–2 μM) reversibly inhibited the ATP-dependent gating of native KACh channels in atrial cells and hippocampal neurons, and of recombinant KACh channels (GIRK1/4 and GIRK1/2) expressed in oocytes. Unsaturated free fatty acids also inhibited phosphatidylinositol-4,5-bisphosphate (PIP2)-induced changes in KACh channel kinetics but were ineffective against ATP-activated background K1 channels and PIP2-activated KATP channels. These results show that during agonist-induced activation, unsaturated free fatty acids in the cytoplasm help to keep the cardiac and neuronal KACh channels downregulated by antagonizing their ATP-dependent gating. The opposing effects of ATP and free fatty acids represent a novel regulatory mechanism for the G protein–gated K+ channel.
Single Channel Studies of Inward Rectifier Potassium Channel Regulation by Muscarinic Acetylcholine Receptors
Authors: Bard Joel , Kunkel Maya T. , Peralta Ernest G.
Published: July 2002

Negative regulation of the heartbeat rate involves the activation of an inwardly rectifying potassium current (IKACh) by G protein–coupled receptors such as the m2 muscarinic acetylcholine receptor. Recent studies have shown that this process involves the direct binding of Gβγ subunits to the NH2- and COOH-terminal cytoplasmic domains of the proteins termed GIRK1 and GIRK4 (Kir3.1 and Kir3.4/CIR), which mediate IKACh. Because of the very low basal activity of native IKACh, it has been difficult to determine the single channel effect of Gβγ subunit binding on IKACh activity. Through analysis of a novel G protein–activated chimeric inward rectifier channel that displays increased basal activity relative to IKACh, we find that single channel activation can be explained by a G protein–dependent shift in the equilibrium of open channel transitions in favor of a bursting state of channel activity over a long-lived closed state.
The deconstructed journal — a new model for academic publishing
Authors: Smith John W T
Published: July 2002

The limitations of existing proposed and operational publishing models intended to replace the academic journal are briefly reviewed. Three ‘insights’ are described, the first is into the ‘means/end’ confusion of much current net‐based publishing activity, the second is that it is the purpose, not the form, that is the important aspect of the traditional academic journal model, and the third is that satisfactory net‐based publishing models need not contain a central publisher. From this new viewpoint is developed the Deconstructed Journal (DJ) model which it is suggested is a better model for network based academic publishing. It also solves some of the problems of the current model. Although the main focus of the DJ model is the replacement of the STM journal it has implications for all areas of academic journal publishing.
Non-amenable finitely presented torsion-by-cyclic groups
Authors: Ol’shanskii A. , Sapir M.
Published: July 2002

We construct a finitely presented non-amenable group without free non-cyclic subgroups thus providing a finitely presented counterexample to von Neumann’s problem. Our group is an extension of a group of finite exponent

n
≫
1

n\gg 1

by a cyclic group, so it satisfies the identity

[
x
,
y

]
n

=
1

[x,y]^n=1

.
Transmission of ocular media in labrid fishes
Authors: Siebeck Ulrike E. , Marshall N. Justin
Published: July 2002

Wrasses (Labridae) are the second largest family of fishes on the Great Barrier Reef (after the Gobiidae) and, in terms of morphology and lifestyle, one of the most diverse. They occupy all zones of the reef from the very shallow reef flats to deep slopes, feeding on a variety of fauna. Many wrasses also have elaborately patterned bodies and reflect a range of colours from ultraviolet (UV) to far red. As a first step to investigating the visual system of these fishes we measured the transmission properties of the ocular media of 36 species from the Great Barrier Reef, Australia, and Hawaii, California and the Florida Keys, USA. Transmission measurements were made of whole eyes with a window cut into the back, and also of isolated lenses and corneas. Based on the transmission properties of the corneas the species could be split into two distinct groups within which the exact wavelength of the cut–off was variable. One group had visibly yellow corneas, while the corneas of the other group appeared clear to human observers. Five species had ocular media that transmitted wavelengths below 400 nm, making a perception of UV wavelengths for those species possible. Possible functional roles for the different filter types are discussed.
Dependence of computer classification of clustered microcalcifications on the correct detection of microcalcifications
Authors: Jiang Yulei , Nishikawa Robert M. , Papaioannou John
Published: July 2002

Our purpose was to study the dependence of computer performance in classifying clustered microcalcifications as malignant or benign on the correct detection of microcalcifications. Specifically, we studied the effects of computer‐detected true‐positive microcalcifications and computer‐detected false‐positive microcalcifications in true microcalcification clusters. Using a database of 100 mammograms, we compared computer classification performance obtained from computer‐detected microcalcifications to (1) computer classification performance obtained from manually identified microcalcifications, and (2) radiologists' performance. When an artificial neural network (ANN) was trained with manually identified microcalcifications, computer classification performance was comparable to or better than radiologists' performance as the number of computer‐detected true‐positive microcalcifications decreased to 40% and as the number of computer‐detected false‐positive microcalcifications increased to 50%. Further loss in computer‐detected true‐positive microcalcifications degraded classification performance substantially. Moreover, training the ANN with computer‐detected microcalcifications also degraded computer classification performance. These results show that computer performance in classifying clustered microcalcifications as malignant or benign is insensitive to moderate decreases in computer‐detected true‐positive microcalcifications and moderate increases in computer‐detected false‐positive microcalcifications.
Einstein’s hole argument
Authors: Macdonald Alan
Published: July 2002

In general relativity, space and time are inseparable from a gravitational field: no field, no spacetime. This is a lesson of Einstein’s hole argument. We use a simple transformation in a Schwartzschild spacetime to illustrate this. On the basis of the general theory of relativity … space as opposed to “what fills space” … has no separate existence. … There is no such thing as an empty space, i.e., a space without [a gravitational] field. … Spacetime does not claim existence on its own, but only as a structural quality of the field. Albert Einstein, 1952.
The origins of length contraction: I. The FitzGerald–Lorentz deformation hypothesis
Authors: Brown Harvey R.
Published: July 2002

“Can there be some point in the theory of Mr. Michelson’s experiment which has yet been overlooked?” H. A. Lorentz, letter to Lord Rayleigh, August 1892.   One of the widespread confusions concerning the history of the 1887 Michelson–Morley experiment has to do with the initial explanation of this celebrated null result due independently to FitzGerald and Lorentz. In neither case was a strict, longitudinal length contraction hypothesis invoked, as is commonly supposed. Lorentz postulated, particularly in 1895, any one of a certain family of possible deformation effects for rigid bodies in motion, including purely transverse alteration, and expansion as well as contraction; FitzGerald may well have had the same family in mind. A careful analysis of the Michelson–Morley experiment (which reveals a number of serious inadequacies in many textbook treatments) indeed shows that strict contraction is not required.
Acoustical and physical dynamics of the diatonic harmonica
Authors: Bahnson Henry T. , Antaki James F. , Beery Quinter C.
Published: July 2002

The harmonica is arguably the most widely played instrument in the world, yet there is a surprising paucity of published studies of its acoustics or physical dynamics. The typical diatonic harmonica and the physical forces involved in its natural function are described, and simple observations of the harp’s functions are reported. The speaking of the reeds, naturally, when producing a bend, and when speaking as an overblow or overdraw is discussed and investigated by simple stopping of the reeds, by videostroboscopic analysis, and by recording vibration of the reeds with displacement gauges. The reeds of the ten hole harmonica can be made to vibrate at varying frequencies depending on the size and shape of the player’s vocal tract. Three different modes of speaking from each hole and its pair of reeds are revealed and studied: first, naturally in a closing mode, either blown or drawn; second, as a bend, either blown or drawn, with pitch in the interval between the two notes in the hole; and third, as an overblow or overdraw in an opening mode with a pitch outside the interval between the two natural notes of the hole. This dynamic interaction allows the player to speak with the instrument perhaps as with no other.
Assessment of tire/pavement interaction noise under vehicle passby test conditions using sound intensity measurement methods
Authors: Donavan Paul R. , Schumacher Richard F. , Stott Jeffrey R.
Published: July 2002

Over the past several years, sound intensity measurement methods have become an increasing valuable tool in isolating tire/pavement interaction noise when a vehicle is tested under full throttle acceleration conditions such as the ISO 362 R15 procedure. Several investigations have been conducted and reported which demonstrate the relationship between ‘‘on-board’’ sound intensity measured close to a tire contact patch and the sound pressure level measured by a stationary microphone 7.5 m away from the line of travel of the vehicle. Using these relationships, the contribution of tire/pavement noise can be assessed relative to other noise sources associated with a vehicle under acceleration as measured at 7.5 m. In this application, it has been determined that some tires can produce significantly higher noise levels under the torque of acceleration than under cruise conditions. Sound intensity has also been used to separate sound propagation from sound generation effects in the assessment of test surfaces such as those specified by SAE and ISO. This paper reviews the various applications of sound intensity in the assessment of tire/pavement interaction noise issues related to vehicle passby noise, the implication of recent findings on noise reduction strategies, and the potential for standardization of sound intensity techniques.
Hot-spot model of single-bubble sonoluminescence
Authors: Yasui Kyuichi
Published: July 2002

The hot-spot model of single-bubble sonoluminescence (SBSL) is studied. The temperature is assumed to be spatially uniform inside the bubble except at the thermal boundary layer near the bubble wall even at the strong collapse based on the theoretical results by Kwak et al. [Phys. Rev. Lett. 77, 4454 (1996)]. The effect of the kinetic energy of gases inside the bubble is taken into account, which heats up the whole bubble when gases stop their motions at the end of the strong collapse. A bubble in water containing air is assumed to consist mainly of argon based on the hypothesis by D. Lohse [D. Lohse et al., Phys. Rev. Lett. 78, 1359 (1997)]. Numerical calculations under an SBSL condition reveal that the kinetic energy of gases heats up the whole bubble considerably. It is also clarified that vapor molecules (H2O) undergo chemical reactions in the heated interior of the bubble at the collapse and that chemical reactions decrease the temperature inside the bubble considerably. It is suggested that SBSL originates in quasithermal radiation from the whole bubble rather than a local point (the bubble center) heated by a converging spherical shock wave widely suggested in the previous theories of SBSL.
Thermal processes in the oscillations of gas bubbles in tubes
Authors: Chen X. M. , Prosperetti A.
Published: July 2002

The forced oscillations of a system consisting of two finite liquid columns in a duct separated by a gas bubble are studied in the linear approximation. It is found that thermal processes in the gas induce a very significant damping in the system, which can exceed viscous damping even in capillaries with a submillimeter diameter. The study is motivated by the possibility of using gas bubbles as actuators in microdevices.
Powder X-ray characterization of djenkolic acid
Authors: Melnikov Petr , Cuin Alexandre , Corbi Pedro P. , Cavicchioli Maurício , Massabni Antonio C.
Published: July 2002

X-ray powder diffraction data for the orthorhombic natural amino acid djenkolic acid, C7H14N2O4S2, is described in this paper. The orthorhombic cell parameters are:a=8.12 Å,b=12.16 Å, andc=5.38 Å
Characterization of US State COVID-19 Vaccine Incentive Programs
Authors: Hogan Caroline M. , Parzuchowski Aaron S. , Lyu Xiru , Goldstick Jason , Resnicow Kenneth
Published: October 2022

This cross-sectional study describes and compares key characteristics of state COVID-19 vaccine incentive programs in the US.
Molecular isolation and expression analysis of hemocyanin isoform 2 of Macrobrachium rosenbergii
Authors: Srisuk Chutima , Choolert Chanitcha , Bendena William G. , Longyant Siwaporn , Sithigorngul Paisarn , Chaivisuthangkura Parin
Published: October 2022

Objective

Hemocyanin is a copper-bearing protein in the hemolymph of many arthropods and mollusks and functions as an oxygen transport and important nonspecific immune protein.

Methods

In this study, complementary DNA of hemocyanin isoform 2 of the prawn Macrobrachium rosenbergii (MrHc2) was isolated by rapid amplification of cDNA ends and mRNA expression was characterized to elucidate molecular basis of its function.

Result

With a molecular mass of 77.3 kDa, MrHc2 contained three domains: hemocyanin-all-alpha, hemocyanin-copper-containing, and hemocyanin-immunoglobulin-like domains. Molecular phylogenetic analysis revealed that MrHc2 belongs to the γ-type subunit and is closely related to hemocyanin subunit 1 of the palaemonid shrimp Macrobrachium nipponense. In addition, MrHc2 resided in a different clade relative to hemocyanin (MrHc) of M. rosenbergii (α-type subunit) and in a different subclade relative to the hemocyanin proteins of penaeid shrimp. The messenger RNA transcript of MrHc2 was highly expressed in the hepatopancreas and weakly expressed in the gills, intestine, stomach, muscle, and hemocytes. Upon challenge with M. rosenbergii nodavirus (MrNV), the expression of MrHc2 was 1.96-, 2.93-, and 1.96-fold on days 3, 4, and 5, respectively, and then gradually declined to basal levels on day 7.

Conclusion

This study suggests that MrHc2 plays an important role in the innate immune response of M. rosenbergii to MrNV.
Ruan posed to bear fruit for more liberal prescribing
Authors: Knopf Alison
Published: October 2022

The unanimous ruling by the U.S. Supreme Court this summer which heralded possible liberalization of opioid and other controlled substance prescribing appears to be bearing fruit. Fewer physicians, based on mainly off‐the‐record interviews and comments, are afraid of the Drug Enforcement Administration (DEA) in the wake of the Supreme Court's ruling on Ruan v. United States, in which two physicians had been accused of running “pill mills.” The basis of the ruling was that physicians should have a defense based on good faith (see Supreme Court rejects standard underlying prosecutions of opioid prescribers, ADAW July 11, https://onlinelibrary.wiley.com/doi/10.1002/adaw.33491). According to the opinion, in order to convict a prescriber for unauthorized distribution of a controlled substance, the government must use a subjective standard that the physician knowingly believed he or she was unlawfully distributing drugs.
Semiconductor Halogenation in Molecular Highly‐Oriented Layered p–n (n–p) Junctions
Authors: Cojocariu Iulia , Jugovac Matteo , Sarwar Sidra , Rawson Jeff , Sanz Sergio , Kögerler Paul , Feyer Vitaliy , Schneider Claus Michael
Published: October 2022

Organic p–n junctions attract widespread interest in the field of molecular electronics because of their unique optoelectronic singularities. Importantly, the molecular donor/acceptor character is strongly correlated to the degree of substitution, e.g., the introduction of electron‐withdrawing groups. Herein, by gradually increasing the degree of peripheral fluorination on planar, D4h−symmetric iron(II) phthalocyanato (FePc) complexes, the energy level alignment and molecular order is defined in a metal‐supported bilayered Pc‐based junction using photoemission orbital tomography. This non‐destructive method selectively allows identifying molecular levels of the hetero‐architectures. It demonstrates that, while the symmetric fluorination of FePc does not disrupt the long‐range order and degree of metal‐to‐molecule charge transfer in the first molecular layer, it strongly impacts the energy alignment in both the interface and topmost layer in the bilayered structures. The p–n junction formed in the bilayer of perhydrogenated FePc and perfluorinated FeF16Pc may serve as an ideal model for understanding the basic charge‐transport phenomena at the metal‐supported organic–organic interfaces, with possible application in photovoltaic devices.
Highly Stable and End‐group Tuneable Metal–Organic Framework/Polymer Composite for Superior Triboelectric Nanogenerator Application
Authors: More Yogeshwar D. , Saurabh Satyam , Mollick Samraj , Singh Sachin Kumar , Dutta Subhajit , Fajal Sahel , Prathamshetti Anil , Shirolkar Mandar M. , Panchal Suresh , Wable Minal , Ogale Satishchandra , Ghosh Sujit K.
Published: October 2022

Triboelectric nanogenerators (TENGs) are receiving significant attention lately as efficient mechanical energy harvesting devices. They are finding multiple uses in numerous low‐power applications. Current TENG designs, although innovative, fall short on practical demands like performance tunability, modulatory, and stability. This invites further research in the use of new materials for TENGs. Metal‐organic frameworks (MOFs) offer a unique feature of molecular tunability to optimize energy conversion which has been exploited in this study. Prototypal hybridization strategy is deployed on underexplored isoreticular subfamily UiO‐66(Zr) MOFs through UiO‐66‐X/PVDF (X = H or Br) composites for TENG output tuning and amplification. UiO‐66‐X/PVDF exhibits good aquatic and thermal stability accompanying substantial boost in TENG power. Functionalized H2BDC linker improved surface roughness and potential. UiO‐66‐Br encased in PVDF matrix boosted charge and TENG performance by enhancing electrification. Computational details support observations. Device captures waste energy in a vertical contact‐separation mode and functions consistently amidst diverse environmental settings. Functionalized TENG‐2 delivers a Vp–p of 110.41 V, which is 2.92 times and 14.12 times higher than unfunctionalized TENG‐1 and PVDF film, respectively. Findings reveal maiden example of ligand‐mediated functional group‐driven performance tuning of TENG and mechanistic insight using isoreticular MOFs/PVDF composites.
Thermally Induced Mechanical Switching of the Second‐Harmonic Generation in pNIPAM Hydrogels‐Linked Resonant Au and Si Nanoparticles
Authors: Gerasimova Elena N. , Yaroshenko Vitaly V. , Mikhailova Lidia V. , Dolgintsev Dmitry M. , Timin Alexander S. , Zyuzin Mikhail V. , Zuev Dmitry A.
Published: October 2022

Nanostructures enabling light manipulation in response to external stimuli offer unprecedented opportunities for efficient control over optomechanical systems at the nanoscale. The integration of stimuli‐responsive materials in such systems is an important milestone in the creation of miniaturized and smart nano‐ and micromechanical systems. In this article, a thermally sensitive mechanically driven platform based on pNIPAM microspheres modified with high refractive index dielectric silicon (Si) and plasmonic gold (Au) nanoparticles is presented to probe the temperature‐dependent reversible mechanical transformations through the second‐harmonic generation signal switching. The second‐harmonic generation process is investigated theoretically and experimentally depending on the applied temperature and pNIPAM phase. It is found that the change of the interparticle distance in the system during the phase transition provokes generation of optically induced static electric field probed by the second‐harmonic generation signal. The obtained results can become the foundation in the creation of nanophotonic devices based on thermo‐sensitive polymers, as they combine reversible tuning of optical signals with the opportunity of local probing of mechanical changes.
Unraveling the Atomic‐Level Manipulation Mechanism of Li2S Redox Kinetics via Electron‐Donor Doping for Designing High‐Volumetric‐Energy‐Density, Lean‐Electrolyte Lithium–Sulfur Batteries
Authors: Shan Jiongwei , Wang Wei , Zhang Bing , Wang Xinying , Zhou Weiliang , Yue Liguo , Li Yunyong
Published: October 2022

Designing dense thick sulfur cathodes to gain high‐volumetric/areal‐capacity lithium–sulfur batteries (LSBs) in lean electrolytes is extremely desired. Nevertheless, the severe Li2S clogging and unclear mechanism seriously hinder its development. Herein, an integrated strategy is developed to manipulate Li2S redox kinetics of CoP/MXene catalyst via electron‐donor Cu doping. Meanwhile a dense S/Cu0.1Co0.9P/MXene cathode (density = 1.95 g cm−3) is constructed, which presents a large volumetric capacity of 1664 Ah L−1 (routine electrolyte) and a high areal capacity of ≈8.3 mAh cm−2 (lean electrolyte of 5.0 µL mgs−1) at 0.1 C. Systematical thermodynamics, kinetics, and theoretical simulation confirm that electron‐donor Cu doping induces the charge accumulation of Co atoms to form more chemical bonding with polysulfides, whereas weakens CoS bonding energy and generates abundant lattice vacancies and active sites to facilitate the diffusion and catalysis of polysulfides/Li2S on electrocatalyst surface, thereby decreasing the diffusion energy barrier and activation energy of Li2S nucleation and dissolution, boosting Li2S redox kinetics, and inhibiting shuttling in the dense thick sulfur cathode. This work deeply understands the atomic‐level manipulation mechanism of Li2S redox kinetics and provides dependable principles for designing high‐volumetric‐energy‐density, lean‐electrolyte LSBs through integrating bidirectional electro‐catalysts with manipulated Li2S redox and dense‐sulfur engineering.
Carbon Nanotube Ink Dispersed by Chitin Nanocrystals for Thermoelectric Converter for Self‐Powering Multifunctional Wearable Electronics
Authors: He Yunqing , Lin Xiaoying , Feng Yue , Luo Binghong , Liu Mingxian
Published: October 2022

The screen‐printing process of conductive ink can realize simple and large‐scale manufacture of micro/nano patterns for producing wearable electronic products. Herein, chitin nanocrystals (ChNCs) are used as a dispersant for the preparation of multiwalled carbon nanotube (MWCNT) ink with high viscosity and uniformity by ultrasound treatment. ChNCs can interact with MWCNT in noncovalent ways, including π–π and hydrophobic interactions. ChNCs/MWCNT (CCNT) ink does not aggregate even after standing for 3 months with a maximum MWCNT concentration of 33 mg mL−1 and dispersion efficiency of 91.1%. Using CCNT ink, a paper‐based thermoelectric generator (TEG) is manufactured by screen‐printing technology. With good thermoelectric and strain sensing properties, CCNT coated paper can stably collect human energy at room temperature to realize self‐powering. The CCNT coated paper‐based TEG can convert thermal voltage signals into musical notes, monitor the changes in human behavior and respiratory rate, and monitor joint movements. Moreover, CCNT coated paper has no cytotoxicity by CCK‐8 and live/dead staining. This work puts forward a strategy of green preparation of MWCNT‐based ink by adding renewable chitin, which opens up a new way to apply MWCNT‐based ink in self‐powering wearable multifunctional sensors.
Low‐Voltage and High Thermal Stability Single‐Element Te Selector with Failed Bit Pruning Operation Enabling Robust Cross‐Point Memory
Authors: Ding Yaxin , An Junjie , Shen Jiabin , Jia Shujing , Guo Jingrui , Wang Lingfei , Gong Tiancheng , Jiang Pengfei , Wang Yuan , Chen Yuting , Zhu Min , Dou Chunmeng , Luo Qing
Published: October 2022

The breakdown (BD) of one‐selector‐one‐resistor memory cells incurs increasing crosstalk and power consumption in the cross‐point memory array. In this work, failed bit pruning (FBP) operation of selectors is presented to cope with the side effects due to the BD cells. First, the FBP concept and its requirements on the device parameters is presented. Then the wide existence of FBP operation is demonstrated by investigating five different materials. Among them, the single‐element (Te) selector is highlighted. It not only shows high resistance after the prune operation (>50 MΩ) under a low prune voltage (2 V) but also achieves low threshold voltage (1.3 V) and high thermal stability (430 °C). This work demonstrates a new universal character for selector devices to enable robust high‐density cross‐point memory.
Dual‐Site Synergistic Passivation for Highly Efficient and Stable Perovskite Solar Cells
Authors: Zhang Wenyuan , He Lang , Meng Yan , Kanda Hiroyuki , Tang Dongyan , Ding Bin , Ding Yong , Nazeeruddin Mohammad Khaja , Li Xin
Published: October 2022

Defect passivation has been recognized as an effective strategy to improve efficiency and stability of perovskite solar cells (PSCs). In this work, in‐depth theoretical calculations and experimental characterizations reveal the dual‐site synergistic passivation of 1H‐benzimidazole (BIZ), and the conjugated structure of the benzene ring tends to increase the interaction between BIZ and perovskite. High‐quality perovskite films are thus achieved, with increased grain size, reduced defect density, and suppressed ion migration. Simultaneously, the reduced work function and optimized band alignment promote carrier transport, reducing nonradiative recombination, and loss of open‐circuit voltages, as well as fill factor. Consequently, the target PSC devices achieve a champion power conversion efficiency (PCE) of 24.59%, and 20.49% for perovskite solar module (a designated area of 27.5 cm2). The unencapsulated PSC maintains 91.49% of original PCE after storing in air with an average relative humidity of 40% for 2400 h. Moreover, the device exhibits remarkable the long‐term operational stability, maintaining 90.47% of initial PCE after continuously operating at the maximum power point for 1000 h. This study not only provides insights into the synergistic passivation of BIZ but also provides a strategy for the application of BIZ derivatives in the photovoltaic field.
Challenges, Opportunities, and Prospects in Metal Halide Perovskites from Theoretical and Machine Learning Perspectives
Authors: Myung Chang Woo , Hajibabaei Amir , Cha Ji‐Hyun , Ha Miran , Kim Junu , Kim Kwang S.
Published: October 2022

Metal halide perovskite (MHP) is a promising next generation energy material for various applications, such as solar cells, light emitting diodes, lasers, sensors, and transistors. MHPs show excellent mechanical, dielectric, photovoltaic, photoluminescence, and electronic properties, and such intriguing physical and chemical properties have drawn attention recently. However, there exists a chasm between the successful applications of MHPs and theoretical understandings. The difficulty arises from the intrinsic properties of MHPs, including structural disorder, ionic interactions, nonadiabatic effects, and composition diversity. Machine learning (ML) approaches have shown great promise as a tool to overcome the theoretical obstacles in many fields of science. In this perspective, the pending theoretical challenges from experiments are overviewed and promising ML approaches, including ab initio ML potentials, materials design/optimization models, and data mining strategies are proposed. Possible roles and pipelines of ML frameworks are highlighted to close the gap between experiment and theory in MHPs.
Highly Stable Lithium Metal Batteries by Regulating the Lithium Nitrate Chemistry with a Modified Eutectic Electrolyte
Authors: Liang Yihong , Wu Wanbao , Li Deping , Wu Hao , Gao Chaochao , Chen Zhengjian , Ci Lijie , Zhang Jiaheng
Published: October 2022

Lithium nitrate is widely used as an additive in electrolytes to regulate the solid electrolyte interphase (SEI). However, the application of LiNO3 in lithium metal batteries (LMBs) is limited by its extremely low solubility in conventional carbonate‐based electrolytes. In this study, a non‐flammable deep eutectic solvent (DES) with lithium bis(trifluoromethanesulfonyl)imide and N‐methylacetamide (NMAC) as the main components is chosen as the LMB electrolyte. Using theoretical calculations and experiments, the strong interaction between NMAC and LiNO3 is proved to be effective in increasing the solubility of LiNO3 (up to 4 wt%) and realizing stable anion‐rich SEI layers. DES synergizes with LiNO3 to produce LiF, LixN, and LiNxOy enriched SEI layer, which improves the uniformity of lithium deposition. In particular, the NCM622||DES‐2||Li full cells achieve 84% capacity retention after 600 cycles at 0.5 C, far exceeding that of conventional carbonate electrolytes (56%). Consequently, this study provides a new strategy for employing LiNO3 in LMBs, in addition to its potential application in other alkali metal batteries and anode‐free batteries.
Interrogating the impact of aggregation‐induced emission nanoparticles on in vitro protein stability, ex vivo protein homeostasis, and in vivo biocompatibility
Authors: Wan Wang , Zhao Qun , Jing Biao , Peng Congcong , Wang Mengdie , Huang Yanan , Jin Wenhan , Zhong Bowen , Zhang Zhenduo , Dong Xuepeng , Gao Zhenming , Zhang Lihua , Liu Yu
Published: October 2022

Aggregation‐induced emission (AIE) materials offer promising perspectives in disease diagnosis and therapeutics given their unique optical and photochemical properties. A key step toward translational applications for AIE materials is to systematically and vigorously evaluate their biosafety and biocompatibility. While previous studies focus on cellular viability and toxicity, the impact of AIE materials on detailed stress responses manifesting cellular fitness has been less explored. Herein, this work provides the first piece of evidence to support amphiphilic functionalization of AIE nanoparticles minimizes the deterioration on proteome stability and cellular protein homeostasis (proteostasis). To this end, four scaffolds of AIE molecules were prepared, further functionalized into eight nanoparticles with two amphiphilic shells respectively, and characterized for their physicochemical properties. Thermal shift assay quantitatively demonstrates that AIE materials after amphiphilic functionalization into nanoparticles enhance proteome thermodynamic stability and ameliorate proteome aggregation propensity in cellular lysate, echoed by cell viability and fractionation experiments. Intriguingly, poor polydispersity index (PDI) of functionalized nanoparticles exaggerates their retention and aggregation in the cell. Comparative proteomic analysis uncovers that amphiphilic functionalization of AIE materials can minimize the deterioration of cellular protein homeostasis network. Finally, vigorous interrogation of functionalized AIE nanoparticles in mice model reveals the complexity of factors affecting the biocompatibility profiles in vivo, including materials’ size, PDI, and treatment frequencies. Overall, amphiphilic functionalization of AIE materials into nanoparticles is necessary to maintain proteome stability and balance cellular protein homeostasis.
Columnar Learning Networks for Multisensory Spatiotemporal Learning
Authors: Yoo Sangmin , Park Yongmo , Wang Ziyu , Wu Yuting , Medepalli Saaketh , Thio Wesley , Lu Wei D.
Published: October 2022

Network features found in the brain may help implement more efficient and robust neural networks. Spiking neural networks (SNNs) process spikes in the spatiotemporal domain and can offer better energy efficiency than deep neural networks. However, most SNN implementations rely on simple point neurons that neglect the rich neuronal and dendritic dynamics. Herein, a bio‐inspired columnar learning network (CLN) structure that employs feedforward, lateral, and feedback connections to make robust classification with sparse data is proposed. CLN is inspired by the mammalian neocortex, comprising cortical columns each containing multiple minicolumns formed by interacting pyramidal neurons. A column continuously processes spatiotemporal signals from its sensor, while learning spatial and temporal correlations between features in different regions of an object along with the sensor's movement through sensorimotor interaction. CLN can be implemented using memristor crossbars with a local learning rule, spiking timing‐dependent plasticity (STDP), which can be natively obtained in second‐order memristors. CLN allows inputs from multiple sensors to be simultaneously processed by different columns, resulting in higher classification accuracy and better noise tolerance. Analysis of networks implemented on memristor crossbars shows that the system can operate at very low power and high throughput, with high accuracy and robustness to noise.