bluuebunny/crossref_metadata_2025 huggingface dataset:
A Dual Role for Src Homology 2 Domain–Containing Inositol-5-Phosphatase (Ship) in Immunity
Authors: Helgason Cheryl D. , Kalberer Christian P. , Damen Jacqueline E. , Chappel Suzanne M. , Pineault Nicolas , Krystal Gerald , Humphries R. Keith
Published: July 2002

In this report, we demonstrate that the Src homology 2 domain–containing inositol-5-phosphatase (SHIP) plays a critical role in regulating both B cell development and responsiveness to antigen stimulation. SHIP−/− mice exhibit a transplantable alteration in B lymphoid development that results in reduced numbers of precursor B (fraction C) and immature B cells in the bone marrow. In vitro, purified SHIP−/− B cells exhibit enhanced proliferation in response to B cell receptor stimulation in both the presence and absence of Fcγ receptor IIB coligation. This enhancement is associated with increased phosphorylation of both mitogen-activated protein kinase and Akt, as well as with increased survival and cell cycling. SHIP−/− mice manifest elevated serum immunoglobulin (Ig) levels and an exaggerated IgG response to the T cell–independent type 2 antigen trinitrophenyl Ficoll. However, only altered B cell development was apparent upon transplantation into nonobese diabetic–severe combined immunodeficient (NOD/SCID) mice. The in vitro hyperresponsiveness, together with the in vivo findings, suggests that SHIP regulates B lymphoid development and antigen responsiveness by both intrinsic and extrinsic mechanisms.
The Notch Ligand Jagged-1 Represents a Novel Growth Factor of Human Hematopoietic Stem Cells
Authors: Karanu Frances N. , Murdoch Barbara , Gallacher Lisa , Wu Dongmei M. , Koremoto Masahide , Sakano Seiji , Bhatia Mickie
Published: July 2002

The Notch ligand, Jagged-1, plays an essential role in tissue formation during embryonic development of primitive organisms. However, little is known regarding the role of Jagged-1 in the regulation of tissue-specific stem cells or its function in humans. Here, we show that uncommitted human hematopoietic cells and cells that comprise the putative blood stem cell microenvironment express Jagged-1 and the Notch receptors. Addition of a soluble form of human Jagged-1 to cultures of purified primitive human blood cells had modest effects in augmenting cytokine-induced proliferation of progenitors. However, intravenous transplantation of cultured cells into immunodeficient mice revealed that human (h)Jagged-1 induces the survival and expansion of human stem cells capable of pluripotent repopulating capacity. Our findings demonstrate that hJagged-1 represents a novel growth factor of human stem cells, thereby providing an opportunity for the clinical utility of Notch ligands in the expansion of primitive cells capable of hematopoietic reconstitution.
Total Charge Movement per Channel
Authors: Sigg Daniel , Bezanilla Francisco
Published: July 2002

One measure of the voltage dependence of ion channel conductance is the amount of gating charge that moves during activation and vice versa. The limiting slope method, introduced by Almers (Almers, W. 1978. Rev. Physiol. Biochem. Pharmacol. 82:96–190), exploits the relationship of charge movement and voltage sensitivity, yielding a lower limit to the range of single channel gating charge displacement. In practice, the technique is plagued by low experimental resolution due to the requirement that the logarithmic voltage sensitivity of activation be measured at very low probabilities of opening. In addition, the linear sequential models to which the original theory was restricted needed to be expanded to accommodate the complexity of mechanisms available for the activation of channels. In this communication, we refine the theory by developing a relationship between the mean activation charge displacement (a measure of the voltage sensitivity of activation) and the gating charge displacement (the integral of gating current). We demonstrate that recording the equilibrium gating charge displacement as an adjunct to the limiting slope technique greatly improves accuracy under conditions where the plots of mean activation charge displacement and gross gating charge displacement versus voltage can be superimposed. We explore this relationship for a wide variety of channel models, which include those having a continuous density of states, nonsequential activation pathways, and subconductance states. We introduce new criteria for the appropriate use of the limiting slope procedure and provide a practical example of the theory applied to low resolution simulation data.
Cysteine Modification of a Putative Pore Residue in Clc-0
Authors: Lin Chia-Wei , Chen Tsung-Yu
Published: July 2002

The ClC channel family consists of chloride channels important for various physiological functions. Two members in this family, ClC-0 and ClC-1, share ∼50–60% amino acid identity and show similar gating behaviors. Although they both contain two subunits, the number of pores present in the homodimeric channel is controversial. The double-barrel model proposed for ClC-0 was recently challenged by a one-pore model partly based on experiments with ClC-1 exploiting cysteine mutagenesis followed by modification with methanethiosulfonate (MTS) reagents. To investigate the pore stoichiometry of ClC-0 more rigorously, we applied a similar strategy of MTS modification in an inactivation-suppressed mutant (C212S) of ClC-0. Mutation of lysine 165 to cysteine (K165C) rendered the channel nonfunctional, but modification of the introduced cysteine by 2-aminoethyl MTS (MTSEA) recovered functional channels with altered properties of gating-permeation coupling. The fast gate of the MTSEA-modified K165C homodimer responded to external Cl− less effectively, so the Po-V curve was shifted to a more depolarized potential by ∼45 mV. The K165C-K165 heterodimer showed double-barrel–like channel activity after MTSEA modification, with the fast-gating behaviors mimicking a combination of those of the mutant and the wild-type pore, as expected for the two-pore model. Without MTSEA modification, the heterodimer showed only one pore, and was easier to inactivate than the two-pore channel. These results showed that K165 is important for both the fast and slow gating of ClC-0. Therefore, the effects of MTS reagents on channel gating need to be carefully considered when interpreting the apparent modification rate.
Gating Kinetics of the α1i T-Type Calcium Channel
Authors: Frazier Charles J. , Serrano Jose R. , George Eric G. , Yu Xiaofeng , Viswanathan Ahalya , Perez-Reyes Edward , Jones Stephen W.
Published: July 2002

The α1I T-type calcium channel inactivates almost 10-fold more slowly than the other family members (α1G and α1H) or most native T-channels. We have examined the underlying mechanisms using whole-cell recordings from rat α1I stably expressed in HEK293 cells. We found several kinetic differences between α1G and α1I, including some properties that at first appear qualitatively different. Notably, α1I tail currents require two or even three exponentials, whereas α1G tails were well described by a single exponential over a wide voltage range. Also, closed-state inactivation is more significant for α1I, even for relatively strong depolarizations. Despite these differences, gating of α1I can be described by the same kinetic scheme used for α1G, where voltage sensor movement is allosterically coupled to inactivation. Nearly all of the rate constants in the model are 5–12-fold slower for α1I, but the microscopic rate for channel closing is fourfold faster. This suggests that T-channels share a common gating mechanism, but with considerable quantitative variability.
Degree of irrationality of a product of two elliptic curves
Authors: Yoshihara Hisao
Published: July 2002

We consider the degree of irrationality

d
r

(
S
)

d_r(S)

of some algebraic surface

S
S

. Firstly we give an estimate of

d
r

(
S
)

d_r(S)

for a surface

S
S

with a structure of a fiber space. Secondly we prove the existence of a nonsingular curve of genus 3 on

E
×
E

E\times E

for a certain elliptic curve

E
E

with complex multiplications. As a corollary, we obtain that

d
r

(
E
×
E
)
=
3

d_r(E\times E)=3

.
Aspergillus nidulansSeptin AspB Plays Pre- and Postmitotic Roles in Septum, Branch, and Conidiophore Development
Authors: Westfall Patrick J. , Momany Michelle
Published: July 2002

Members of the septin family of proteins act as organizational scaffolds in areas of cell division and new growth in a variety of organisms. Herein, we show that in the filamentous fungusAspergillus nidulans, the septin AspB is important for cellular division, branching, and conidiation both pre- and postmitotically. AspB localizes postmitotically to the septation site with an underlying polarity that is evident as cytokinesis progresses. This localization at the septation site is dependent on actin and occurs before the cross-wall is visible. AspB localizes premitotically as a ring at sites of branching and secondary germ tube emergence. It is the only known branch site marker. In addition, AspB is found at several stages during the development of the asexual reproductive structure, the conidiophore. It localizes transiently to the vesicle/metula and metula/phialide interfaces, and persistently to the phialide/conidiospore interface. A temperature-sensitive mutant of AspB shows phenotypic abnormalities, including irregular septa, high numbers of branches, and immature asexual reproductive structures.
Genomic Analysis of Homotypic Vacuole Fusion
Authors: Seeley E. Scott , Kato Masashi , Margolis Nathan , Wickner William , Eitzen Gary
Published: July 2002

Yeast vacuoles undergo fission and homotypic fusion, yielding one to three vacuoles per cell at steady state. Defects in vacuole fusion result in vacuole fragmentation. We have screened 4828 yeast strains, each with a deletion of a nonessential gene, for vacuole morphology defects. Fragmented vacuoles were found in strains deleted for genes encoding known fusion catalysts as well as 19 enzymes of lipid metabolism, 4 SNAREs, 12 GTPases and GTPase effectors, 9 additional known vacuole protein-sorting genes, 16 protein kinases, 2 phosphatases, 11 cytoskeletal proteins, and 28 genes of unknown function. Vacuole fusion and vacuole protein sorting are catalyzed by distinct, but overlapping, sets of proteins. Novel pathways of vacuole priming and docking emerged from this deletion screen. These include ergosterol biosynthesis, phosphatidylinositol (4,5)-bisphosphate turnover, and signaling from Rho GTPases to actin remodeling. These pathways are supported by the sensitivity of the late stages of vacuole fusion to inhibitors of phospholipase C, calcium channels, and actin remodeling. Using databases of yeast protein interactions, we found that many nonessential genes identified in our deletion screen interact with essential genes that are directly involved in vacuole fusion. Our screen reveals regulatory pathways of vacuole docking and provides a genomic basis for studies of this reaction.
Type II Keratins Are Phosphorylated on a Unique Motif during Stress and Mitosis in Tissues and Cultured Cells
Authors: Toivola Diana M. , Zhou Qin , English Luc S. , Omary M. Bishr
Published: July 2002

Epithelial cell keratins make up the type I (K9–K20) and type II (K1–K8) intermediate filament proteins. In glandular epithelia, K8 becomes phosphorylated on S73 (71LLpSPL) in human cultured cells and tissues during stress, apoptosis, and mitosis. Of all known proteins, the context of the K8 S73 motif (LLS/TPL) is unique to type II keratins and is conserved in epidermal K5/K6, esophageal K4, and type II hair keratins, except that serine is replaced by threonine. Because knowledge regarding epidermal and esophageal keratin regulation is limited, we tested whether K4–K6 are phosphorylated on the LLTPL motif. K5 and K6 become phosphorylated in vitro on threonine by the stress-activated kinase p38. Site-specific anti-phosphokeratin antibodies to LLpTPL were generated, which demonstrated negligible basal K4–K6 phosphorylation. In contrast, treatment of primary keratinocytes and other cultured cells, and ex vivo skin and esophagus cultures, with serine/threonine phosphatase inhibitors causes a dramatic increase in K4–K6 LLpTPL phosphorylation. This phosphorylation is accompanied by keratin solubilization, filament reorganization, and collapse. K5/K6 LLTPL phosphorylation occurs in vivo during mitosis and apoptosis induced by UV light or anisomycin, and in human psoriatic skin and squamous cell carcinoma. In conclusion, type II keratins of proliferating epithelia undergo phosphorylation at a unique and conserved motif as part of physiological mitotic and stress-related signals.
GeneRAGE: a robust algorithm for sequence clustering and domain
detection
Authors: Enright Anton J. , Ouzounis Christos A.
Published: July 2002

* To whom correspondence should be addressed.

Motivation: Efficient, accurate and automatic clustering of large protein sequence datasets, such as complete proteomes, into families, according to sequence similarity. Detection and correction of false positive and negative relationships with subsequent detection and resolution of multi-domain proteins.

Results: A new algorithm for the automatic clustering of protein sequence datasets has been developed. This algorithm represents all similarity relationships within the dataset in a binary matrix. Removal of false positives is achieved through subsequent symmetrification of the matrix using a Smith–Waterman dynamic programming alignment algorithm. Detection of multi-domain protein families and further false positive relationships within the symmetrical matrix is achieved through iterative processing of matrix elements with successive rounds of Smith–Waterman dynamic programming alignments. Recursive single-linkage clustering of the corrected matrix allows efficient and accurate family representation for each protein in the dataset. Initial clusters containing multi-domain families, are split into their constituent clusters using the information obtained by the multi-domain detection step. This algorithm can hence quickly and accurately cluster large protein datasets into families. Problems due to the presence of multi-domain proteins are minimized, allowing more precise clustering information to be obtained automatically.

Availability: GeneRAGE (version 1.0) executable binaries for most platforms may be obtained from the authors on request. The system is available to academic users free of charge under license.

Contact: ouzounis@ebi.ac.uk
Translation initiation start prediction in human cDNAs with
high accuracy
Authors: Hatzigeorgiou Artemis G.
Published: July 2002

Motivation: Correct identification of the Translation Initiation Start (TIS) in cDNA sequences is an important issue for genome annotation. The aim of this work is to improve upon current methods and provide a performance guaranteed prediction.

Methods: This is achieved by using two modules, one sensitive to the conserved motif and the other sensitive to the coding/non-coding potential around the start codon. Both modules are based on Artificial Neural Networks (ANNs). By applying the simplified method of the ribosome scanning model, the algorithm starts a linear search at the beginning of the coding ORF and stops once the combination of the two modules predicts a positive score.

Results: According to the results of the test group, 94% of the TIS were correctly predicted. A confident decision is obtained through the use of the Las Vegas algorithm idea. The incorporation of this algorithm leads to a highly accurate recognition of the TIS in human cDNAs for 60% of the cases.

Availability: The program is available upon request from the author.

Contact: agh@pcbi.upenn.edu

2 Present address: Department of Genetics, University of Pennsylvania, School of Medicine, 1407 Blockley Hall, 418 Guardian Drive, Philadelphia, PA 19104-6021, USA.
Prediction of structural domains of TAP reveals details of its interaction with p15 and nucleoporins
Authors: Suyama Mikita , Doerks Tobias , Braun Isabelle C , Sattler Michael , Izaurralde Elisa , Bork Peer
Published: July 2002

Vertebrate TAP is a nuclear mRNA export factor homologous to yeast Mex67p. The middle domain of TAP binds directly to p15, a protein related to the nuclear transport factor 2 (NTF2), whereas its C‐terminal domain interacts with various nucleoporins, the components of the nuclear pore complex (NPC). Here, we report that the middle domain of TAP is also similar to NTF2, as well as to regions in Ras‐GAP SH3 domain binding protein (G3BP) and some plant protein kinases. Based on the known three‐dimensional structure of NTF2 homodimer, a heterodimerization model of TAP and p15 could be inferred. This model was confirmed by site‐directed mutagenesis of residues located at the dimer interface. Furthermore, the C‐terminus of TAP was found to contain a ubiquitin‐associated (UBA) domain. By site‐directed mutagenesis we show that a conserved loop in this domain plays an essential role in mediating TAP–nucleoporin interaction.
CD4 T–cell memory can persist in the absence of class II
Authors: Swain Susan L.
Published: July 2002

To understand how memory CD4 T cells are generated we have re–examined the requirements for continuing antigen stimulation in the generation and persistence of this population. We find that specific antigen is only required for a short period during the activation of naive CD4 Tcells and is not required for memory generation from activated CD4 T cells or for persistence of resting memory cells generated by transfer of activated CD4 to adoptive hosts. Moreover, transfer of activated CD4 T cells to class–II–deficient hosts, indicates that T cR–class II major histocompatibility interaction is also unnecessary for either the transition from activated CD4 T cell to resting memory cells or for persistence over an eightweek period. Thus the signals regulating generation and maintenance of memory are fundamentally different from those which regulate the expansion of effector CD4 T–cell populations which include antigen itself and the CD4 T–cell autocrine cytokines induced by antigen.
Somatic hypermutation of immunoglobulin and non–immunoglobulin genes
Authors: Storb Ursula , Ming Shen Hong , Michael Nancy , Kim Nayun
Published: July 2002

Somatic hypermutation (SHM) of immunoglobulin (Ig) genes is a highly specific mechanism restricted to B lymphocytes during only a few cell generations. Data presented here suggest that transcription of the target genes is required, but not sufficient for SHM. Presumably,cis–acting elements, such as those present in the Ig enhancers, are required to target a mutator factor (MuF) to Ig and humanBCL–6genes. It is postulated that the MuF travels with the transcribing RNA polymerase and is deposited on the target gene when the polymerase pauses. Point mutations, and rare deletions and insertions, are created by the combined actions of MuF and certain DNA polymerases. A subset of the mutations is corrected during SHM by DNA mismatch repair.
A Clone-Array Pooled Shotgun Strategy for Sequencing Large Genomes
Authors: Cai Wei-Wen , Chen Rui , Gibbs Richard A. , Bradley Allan
Published: July 2002

A simplified strategy for sequencing large genomes is proposed. Clone-Array Pooled Shotgun Sequencing (CAPSS) is based on pooling rows and columns of arrayed genomic clones, for shotgun library construction. Random sequences are accumulated, and the data are processed by sequential comparison of rows and columns to assemble the sequence of clones at points of intersection. Compared with either a clone-by-clone approach or whole-genome shotgun sequencing, CAPSS requires relatively few library constructions and only minimal computational power for a complete genome assembly. The strategy is suitable for sequencing large genomes for which there are no sequence-ready maps, but for which relatively high resolution STS maps and highly redundant BAC libraries are available. It is immediately applicable to the sequencing of mouse, rat, zebrafish, and other important genomes, and can be managed in a cooperative fashion to take advantage of a distributed international DNA sequencing capacity.
A tutorial presentation of the two stream instability and Landau damping
Authors: Anderson D. , Fedele R. , Lisak M.
Published: July 2002

A tutorial presentation is given of the interaction between a high frequency electrostatic wave and a plasma. The analysis is carried out in several consecutive simple steps, starting from electrostatic plasma waves in a cold plasma and successively introducing complications like streaming electrons, the two stream instability and eventually the Landau damping phenomenon. The analysis is based only on cold plasma fluid theory and does not involve kinetic Vlasov theory.
Measurement technique for bottom scattering in shallow water
Authors: Holland Charles W. , Hollett Reginald , Troiano Luigi
Published: July 2002

Sonar performance predictions of reverberation in shallow water rely upon good estimates of the bottom-scattering strength. However, little is understood about bottom scattering in shallow water in the frequency range 400–4000 Hz, particularly its dependency upon frequency and its relationship to the physical properties of the seafloor. In order to address these issues, a new measurement technique has been developed to probe the frequency and angular dependency of bottom-scattering strength. The experimental technique is described which employs either coherent or incoherent sources (lightbulbs). In addition, measurement and modeling results for two diverse shallow water sites are presented. At one site, the scattering appears to arise at or near the water–sediment interface. At the other site, scattering from a 23-m sub-bottom horizon is clearly apparent in the data at and below 1800 Hz. The fact that our measurement technique can directly reveal the presence of sub-bottom scattering is a significant advance in the development of methods to explore the physical mechanisms that control bottom scattering.
Vibration of truss structures
Authors: Bondaryk Joseph E.
Published: July 2002

Recent trends in underwater vehicle design suggest the use of trusslike structures to support vibrating machinery. Experimental measurements are used to understand the dynamic behavior of a set of 1:15 model, three-dimensional truss structures over the full scale equivalent frequency range 10–1400 Hz. A cubic truss with all equal struts, a rectangular truss with two strut sizes, and a less practical truss composed of pyramid-shaped cells are considered. In conjunction with experiments, a direct global stiffness matrix numerical model is used to identify fundamental truss processes. The periodic nature of trusses causes them to act as mechanical comb filters in frequency with 3–5 dB per bay of attenuation at nonresonant frequencies. In trusses with long runs of axial struts, energy is carried down the truss axis primarily by compressional resonances. The spacing of the resonant peaks is controlled by strut length. A filtering strategy uses strut length to reduce the overall truss response via destructive interference of the frequency resonance structures of the individual struts. Multiple periodicities and impedance discontinuities at the truss joints cause the resonant peaks at low frequencies to widen. The consequence of this is that trusses with varied strut lengths tend to a low-pass frequency characteristic. This effect is compared to an equivalent applied damping and is shown to achieve up to 6 dB per bay of attenuation at the higher frequencies.
Infants’ pitch perception: Masking by low- and high-frequency noises
Authors: Rogers Montgomery Christine , Clarkson Marsha G.
Published: July 2002

The present research employed an operant conditioning procedure typically used with infants to test noise masking of pure tones and tonal complexes in adults and in 7-month-old infants. Adults and infants were presented with either pure tones of 160 and 200 Hz or harmonic tonal complexes with pitches equivalent to 160 and 200 Hz. The tonal complexes did not contain energy at the fundamental frequency. After learning these tasks, subjects in the tonal complex group categorized spectrally varying tonal complexes according to the pitch of the missing fundamental. Stimuli were subsequently presented in combination with either a low- or a high-frequency noise. Both age groups successfully discriminated pure tones when combined with a high-frequency noise but not when combined with a low-frequency noise in the same frequency range as the pure tone. Infants, like adults, successfully categorized harmonic tonal complexes based on the pitch of the missing fundamental when those stimuli were combined with a low-frequency noise in the range of the missing fundamental but not when combined with a high-frequency noise which covered the frequency range of the harmonics themselves. These results suggest that infants rely primarily on a central process and not peripherally generated combination tones to hear the pitch of the missing fundamental.
Erratum: “Elasto-acoustics of a two-dimensional strip by a hybrid method” [J. Acoust. Soc. Am. 102, 955–967 (1997)]
Authors: El-Raheb Michael
Published: July 2002

43.40.Dx, 43.40.Rj, 43.10.Vx [CBB]
Elastic constants of the lithium tantalate crystal in the hypersonic range
Authors: Błachowicz Tomasz , Kleszczewski Zygmunt
Published: July 2002

Elastic constants of the lithium tantalate LiTaO3 crystal were determined in the hypersonic range by the use of the Brillouin laser light scattering method. Obtained values show variation with respect to ultrasonic measurements. Results are interesting because the same effects are qualitatively different in isomorphic lithium niobate LiNbO3 crystal.
Response phase: A view from the inner hair cell
Authors: Cheatham M. A. , Dallos P.
Published: July 2002

Inner hair cell (IHC) responses are recorded from the apical three turns of the guinea pig cochlea in order to define the relationship between hair cell depolarization and position of the basilar membrane. At low frequencies, inner hair cell depolarization is generally observed near basilar membrane velocity to scala vestibuli, reflecting the putative freestanding nature of the IHC’s stereocilia. While this is consistent with previous IHC results, independent of location, and with neural responses for fibers with low best frequencies, it is inconsistent with single-unit results from the base of the cochlea, where response phase is associated with basilar membrane velocity to scala tympani. Results suggest that the temporal disparity between IHC and neural data from the base of the cochlea may relate to several factors that influence transmembrane voltage in IHCs. First, extracellular voltages (Reference 1981; Reference 1982; Reference 1983) can potentially affect low- and high-frequency regions differently because electrical interactions are more likely in the base of the cochlea than in the apex (Reference 1983, Reference 1985). Second, waveform distortion and kinetic properties associated with voltage-dependent ion channels in the IHC’s basolateral membrane can both influence response phase by adding harmonic components and lagging the receptor potential by as much as 90 deg. Third, the velocity dependence of IHCs in the apex appears to extend to higher frequencies than the velocity dependence demonstrated for IHCs in the base of the cochlea. These features, which influence the timing of discharges in the auditory nerve, are compared and evaluated.
Low grazing angle bistatic sea floor scattering on the Florida Atlantic coastal shelf
Authors: Day Christopher M. , Yamamoto Tokuo
Published: July 2002

Observations of bistatic scattering at moderate frequencies 3750 Hz, 7500 Hz, and 15 000 Hz and low grazing angles (2°–20°) are presented with a geoacoustical description of the site. Given a source–receiver separation of 80.7 m, bistatic scattering strengths in the sandy sediments at the measurement site range from −70 to −15 dB. The observed bistatic scattering at low grazing angles depends primarily on the incident bearing angle. Bistatic scattering values are highest along the transect between the source and receiver. Maximum scattering strengths (−20 to −15 dB) appear 30 m from the receiver. Regions of high scattering (>−30 dB) strength are centered along the direct path between the source and receiver. The contribution of volume scattering to the observed scattering pattern is not very clear. However, given the sandy sediments found at the site, roughness scattering is expected to be a major contributor to the observed bistatic scattering patterns.
Inkjet‐Printed, Flexible Full‐Color Photoluminescence‐Type Color Filters for Displays
Authors: Gao Yiyang , Kang Chengbin , Prodanov Maksym F. , Vashchenko Valerii V. , Srivastava Abhishek K.
Published: February 2022

Photoluminescence‐type color filters (PLCFs) are supposed to offer vivid colors and higher power efficiency for modern displays by removing absorption losses of the conventional color filters (CFs). Inkjet printing (IJP) is a versatile and low‐cost method to pattern color converters. But uniformity of the patterns is a big concern. Poor photoluminescence stability is also problematic, especially for the perovskite nanoparticles (PNPs) and quantum color converters. Herein, a porous polymer film (PF) is deployed as a template for IJP. The capillary effect of sub‐micron pores in the PF modifies the rheological process of ink spreading that eliminates the coffee‐ring effect and simultaneously provides photoluminescence (PL) stability. A high‐quality green PNP, and red quantum rod (QR) based CF array onto the PF is successfully printed. A liquid crystal display (LCD) deploying this full‐color PF CFs is demonstrated. Color gamut of the device could reach 96.9% of BT2020. The PF CFs show good PL stability for more than 218 days. Furthermore, the fabricated PF CFs possess great flexibility, and any chromaticity and brightness change after 10 000 times of folding were not observed. Thus, the proposed CF using the PF is highly suitable for flexible display and photonics components.
Laboratory Tests on Performance of Waste‐Clay‐Brick‐Powder Cement Grouting Materials for Ground Improvement in Mine Goaf
Authors: Dun Zhilin , Wang Mengqi , Zou Youfeng , Ren Lianwei
Published: February 2022

Many waste clay bricks have been produced when brick concrete buildings are demolished; at the same time, grouting treatment in goaf ground needs lots of cement. Waste‐clay‐brick‐powder (WCBP) is proposed to replace a large part of the cement to prepare environmentally friendly slurry suitable for ground grouting in mine goaf. Laboratory tests of replacing 50–90% of cement with WCBP are carried out. Bentonite and water‐reducing agent are used to optimize the slurry based on the performance indexes of water‐separation ratio, stone rate, viscosity, setting time, and compressive strength. Scanning electron microscopy (SEM) tests are also conducted to investigate the microscopic mechanism of some WCBP‐cement samples. Test results show that the slurry made of 20% cement, 70% WCBP, 10% bentonite, and 0.15% water‐reducing agent can meet the needs of ground grouting in mine goaf, and its stone rate is 12% higher than that of pure cement slurry. SEM results show that the WCBP in the early stage mainly exerts the microaggregate effect, and the pozzolanic activity in the later stage plays a role in supplementing the strength.
A Bioinspired Fibrous Helix with Periodic Gradient for Directional Fluidic Gates
Authors: Gao Lei , Guo Fengyun , Li Ni , Wang Yan , Guo Ziyi , Xiong Jie , Zhao Yong
Published: February 2022

Liquid transport is of great significance to industry and life, such as microfluidic chip, liquid separation, fluidic gates, and tissue fluid discharge. However, there are still some challenges to achieve well‐controlled directional transports, and the delamination often occurs for the now existing Janus membranes. Herein, fibrous assembly with hierarchically fibrous helix architecture bioinspired by tendrils through electrospinning combined with mechanical twisting technology is engineered and demonstrated. The liquid transport behavior using as fluidic gates by connecting light‐emitting diode (LED) and the resulting liquid separation mechanism were characterized and investigated, respectively. Different from previous materials, due to the existence of distinct periodic alternate gradient interface topology, the hierarchically fibrous helix exhibits a long‐range order and directional liquid transport trajectory as well as improved water management property. This strategy is cost‐effective and can be extended to other fields. The resultant materials are highly promising for applications in actuators, microfluidic chips, and fluidic gates.
Synergistically Detachable Microneedle Dressing for Programmed Treatment of Chronic Wounds
Authors: Ning Tianqin , Yang Fenghe , Chen Danli , Jia Zhenzhen , Yuan Rongqing , Du Zhenqin , Liu Shuaiyin , Yu Yao , Dai Xiaochuan , Niu Xufeng , Fan Yubo
Published: February 2022

Chronic wounds such as diabetic feet undergo a lifetime risk of developing into incurable ulcers. Current treatments for chronic wounds remain unsatisfactory due to the lack of ideal wound dressings that integrate facile dressing change, long‐acting treatment, and high therapeutic efficacy into one system. Herein, a synergistically detachable microneedle (MN) dressing with a dual‐layer structure is presented to enable programmed treatment via one‐time dressing application. Such a dual‐layer dressing MN system (DDMNS) is composed of chitosan (CS) hydrogel dressing (CSHD) on top of a detachable MN patch with a CS tip and a polyvinyl pyrrolidone (PVP) backing substrate incorporated with magnesium (Mg). The synergistic detachment is achieved with the backing Mg/PVP substrate dissolving within minutes due to the local moist environment of the CSHD enhancing the reaction between Mg and inflammation microenvironment. The combined treatment of Mg and panax notoginseng saponins (PNS) loaded in DDMNS achieves antibacterial, neovascularization, and activating a benign immune response so that the three overlapping periods of the inflammation, tissue proliferation, and tissue remodeling of wound healing reach a dynamic balance. This advanced DDMNS provides a facile approach for the programmed treatment of chronic wound management indicating potential value in wound healing and other related biomedical fields.
Topological Antiferromagnetic Van der Waals Phase in Topological Insulator/Ferromagnet Heterostructures Synthesized by a CMOS‐Compatible Sputtering Technique
Authors: Bhattacharjee Nirjhar , Mahalingam Krishnamurthy , Fedorko Adrian , Lauter Valeria , Matzelle Matthew , Singh Bahadur , Grutter Alexander , Will‐Cole Alexandria , Page Michael , McConney Michael , Markiewicz Robert , Bansil Arun , Heiman Don , Sun Nian Xiang
Published: February 2022

Breaking time‐reversal symmetry by introducing magnetic order, thereby opening a gap in the topological surface state bands, is essential for realizing useful topological properties such as the quantum anomalous Hall and axion insulator states. In this work, a novel topological antiferromagnetic (AFM) phase is created at the interface of a sputtered, c‐axis‐oriented, topological insulator/ferromagnet heterostructure—Bi2Te3/Ni80Fe20 because of diffusion of Ni in Bi2Te3 (Ni‐Bi2Te3). The AFM property of the Ni‐Bi2Te3 interfacial layer is established by observation of spontaneous exchange bias in the magnetic hysteresis loop and compensated moments in the depth profile of the magnetization using polarized neutron reflectometry. Analysis of the structural and chemical properties of the Ni‐Bi2Te3 layer is carried out using selected‐area electron diffraction, electron energy loss spectroscopy, and X‐ray photoelectron spectroscopy. These studies, in parallel with first‐principles calculations, indicate a solid‐state chemical reaction that leads to the formation of Ni−Te bonds and the presence of topological antiferromagnetic (AFM) compound NiBi2Te4 in the Ni‐Bi2Te3 interface layer. The Neél temperature of the Ni‐Bi2Te3 layer is ≈63 K, which is higher than that of typical magnetic topological insulators (MTIs). The presented results provide a pathway toward industrial complementary metal−oxide−semiconductor (CMOS)‐process‐compatible sputtered‐MTI heterostructures, leading to novel materials for topological quantum devices.
Evoking Highly Immunogenic Ferroptosis Aided by Intramolecular Motion‐Induced Photo‐Hyperthermia for Cancer Therapy
Authors: Chen Chao , Wang Zaiyu , Jia Shaorui , Zhang Yuan , Ji Shenglu , Zhao Zheng , Kwok Ryan T. K. , Lam Jacky W. Y. , Ding Dan , Shi Yang , Tang Ben Zhong
Published: February 2022

Immunogenic cell death (ICD) through apoptosis or necroptosis is widely adopted to improve the therapeutic effect in cancer treatment by triggering a specific antitumor immunity. However, the tumor resistance to apoptosis/necroptosis seriously impedes the therapeutic effect. Recently, ferroptosis featured with excessive lipid peroxidation is demonstrated capable of bypassing the apoptosis/necroptosis resistance to kill cancer cells. To date, numerous efficient ferroptosis inducers are developed and successfully utilized for sensitizing cancer cells to ferroptosis. Unfortunately, these inducers can hardly generate adequate immunogenicity during induction of ferroptotic cancer cell death, which distinctly attenuates the efficacy of triggering antitumor immune response, therefore leads to unsatisfactory therapeutic effect. Herein, a novel high‐performance photothermal nanoparticle (TPA‐NDTA NP) is designed by exploiting energy via excited‐state intramolecular motion and employed for immensely assisting ferroptosis inducer to evoke highly efficient ICD through ferroptosis pathway. Tumor models with poor immunogenicity are used to demonstrate the tremendously enhanced therapeutic effect endowed by highly enhanced immunogenic ferroptosis in vitro and in vivo by virtue of the NPs. This study sheds new light on a previously unrecognized facet of boosting the immunogenicity of ferroptosis for achieving satisfactory therapeutic effect in cancer therapy.
Water quality concentration trends and loads identify management needs in the Lake Wister watershed
Authors: Lasater Abbie , Haggard Brian
Published: February 2022

Trend analyses of water quality seek to determine whether concentrations of constituents have increased or decreased over time, which can show the effectiveness of management practices or the need for pollutant reduction. The Poteau River watershed (PRW) is a transboundary watershed across Arkansas and Oklahoma and, in Arkansas, has been listed as a priority watershed within the Arkansas Nonpoint Source Pollution Plan since 1998. The Poteau River, Black Fork, and Fourche Maline within the PRW flow into Lake Wister, which is an important reservoir for recreation, fishing, and waterfowl hunting for residents and tourists around eastern Oklahoma. The purpose of this study was to analyze long‐term concentration trends and loads on the major tributaries entering Lake Wister using the Weighted Regression on Time, Discharge, and Season (WRTDS). The largest magnitude of loads came from the Poteau River, but flow normalized (FN) P and sediments have decreased over time, which is a positive impact of watershed management and must be maintained. However, FN N on the Poteau River has increased over time and should be the focus of future management on the Poteau River. Although the magnitude of constituent loads from the Fourche Maline is less than from the Poteau River, increasing FN P is a concern and should be prioritized for management in Oklahoma. The relatively undisturbed Black Fork watershed contributes the smallest loads to Lake Wister, and FN concentrations are decreasing or not changing over time, suggesting a low priority for the Black Fork watershed.
Cu/LaFeO3 as an efficient and stable catalyst for CO2 reduction: Exploring synergistic effect between Cu and LaFeO3
Authors: Zhang Jingpeng , Wang Yaning , Tian Jiaming , Yan Binhang
Published: February 2022

Cu‐based catalysts, which are regarded as the most promising catalysts for CO2 conversion, suffer dramatic deactivation at high temperatures. In this work, LaFeO3, a typical perovskite‐type oxide, is employed to disperse and stabilize Cu particles for the reverse water gas shift reaction. Compared to traditional Cu‐based catalysts, Cu/LaFeO3 exhibits a higher conversion with 100% CO selectivity and better stability at 873 K. Structural and spectroscopic characterization including N2O chemisorption, high‐resolution transmission electron microscopy, in situ x‐ray diffraction, and x‐ray absorption fine structure show that metallic Cu is well dispersed on LaFeO3, forming more Cu‐LaFeO3 interface. CO2 temperature‐programmed surface reaction (CO2‐TPSR), two‐step transient surface reaction (two‐step TSR), and transient in situ diffuse reflectance infrared Fourier transformed spectroscopy experiments demonstrate that the superior activity is attributed to the synergistic effect between the highly dispersed Cu particles for H2 dissociation and the abundant oxygen vacancies in LaFeO3 support for CO2 activation. The synergistic effect between metal and perovskite‐type oxide increases metal‐support interfaces and enhances CO2 activation, leading to a potential application in a variety of chemical reactions.
Exploring Unconventional SAM Analogues To Build Cell‐Potent Bisubstrate Inhibitors for Nicotinamide N‐Methyltransferase
Authors: Iyamu Iredia D. , Vilseck Jonah Z. , Yadav Ravi , Noinaj Nicholas , Huang Rong
Published: February 2022

Nicotinamide N‐methyltransferase (NNMT) methylates nicotinamide and has been associated with various diseases. Herein, we report the first cell‐potent NNMT bisubstrate inhibitor II399, demonstrating a Ki of 5.9 nM in a biochemical assay and a cellular IC50 value of 1.9 μM. The inhibition mechanism and cocrystal structure confirmed II399 engages both the substrate and cofactor binding pockets. Computational modeling and binding data reveal a balancing act between enthalpic and entropic components that lead to II399′s low nM binding affinity. Notably, II399 is 1 000‐fold more selective for NNMT than closely related methyltransferases. We expect that II399 would serve as a valuable probe to elucidate NNMT biology. Furthermore, this strategy provides the first case of introducing unconventional SAM mimics, which can be adopted to develop cell‐potent inhibitors for other SAM‐dependent methyltransferases.
In MOF eingebettete Enzyme für die kontinuierliche Durchflusskatalyse in wässrigen und organischen Lösungsmitteln
Authors: Greifenstein Raphael , Ballweg Tim , Hashem Tawheed , Gottwald Eric , Achauer David , Kirschhöfer Frank , Nusser Michael , Brenner‐Weiß Gerald , Sedghamiz Elaheh , Wenzel Wolfgang , Mittmann Esther , Rabe Kersten S. , Niemeyer Christof M. , Franzreb Matthias , Wöll Christof
Published: February 2022

Um das Potenzial von Enzymen in der zellfreien Biokatalyse voll auszuschöpfen, ist eine Stabilisierung der katalytisch aktiven Proteine und deren Integration in effiziente Reaktorsysteme erforderlich. Obwohl in den letzten Jahren erste Schritte zur Immobilisierung solcher Biomoleküle in metallorganischen Gerüsten (MOFs) unternommen wurden, waren diese Demonstrationen auf Batch‐Experimente und wässrige Bedingungen beschränkt. Hier demonstrieren wir ein kontinuierliches Enzymreaktorsystem auf MOF‐Basis mit hoher Produktivität und Stabilität, das auch für organische Lösungsmittel geeignet ist. Unter wässrigen Bedingungen wurde die Stabilität des Enzyms um das 30‐fache erhöht, und die Raum‐Zeit‐Ausbeute übertraf die mit anderen Enzym‐Immobilisierungsstrategien erzielten Werte um eine Größenordnung. Es ist herauszuheben, dass die hier gezeigte Infiltration der Proteine in das MOF keine zusätzliche Funktionalisierung erfordert, was eine zeit‐ und kosteneffiziente Herstellung der Biokatalysatoren mit markierungsfreien Enzymen ermöglicht.
Ecomorphology of the tarsometatarsus of waterfowl (Anseriformes) based on geometric morphometrics and its application to fossils
Authors: De Mendoza Ricardo Santiago , Gómez Raúl Orencio
Published: February 2022

Anseriformes is a diverse group of birds that comprises screamers, the Magpie Goose, and swans ducks and geese, with a relatively rich fossil record. Waterfowl live in close relation to water bodies, but show a diversity of locomotory habits, being typically categorized as walkers, dabblers, and divers. Owing to its functional significance and high preservation potential, the tarsometatarsus has been considered to be a “key” element upon which to base ecomorphological inferences in fossil waterfowl. For instance, based on features of the tarsometatarsus the Miocene flightless duck Cayaoa bruneti and the Oligocene‐Miocene large waterfowl Paranyroca have been inferred as divers. Herein, we use a geometric morphometric approach and comparative methods to assess the phylogenetic and ecomorphological signals in the shape and size of waterfowl tarsometatarsi in relation to their locomotory habits. We also apply phylogenetic flexible discriminant analysis (pFDA) to test the inferred diving habits in the extinct waterfowl Cayaoa and Paranyroca. Extant waterfowl species are largely distributed according to their locomotory habit along the main axis of variation in the shape space, a pattern mirrored by the phylogenetic generalized least squares model, which shows that a third of the shape variation is significantly explained by the habit. The pFDA reclassifies correctly almost all extant species and classified with high posterior probabilities the fossil Cayaoa and Paranyroca as a diver and as a dabbler, respectively. Our quantitative multivariate approach confirms the tarsometatarsus as a useful source of data upon which reliably assesses locomotory habits of fossil waterfowl.
Economic optimization for a dual‐feedstock lignocellulosic‐based sustainable biofuel supply chain considering greenhouse gas emission and soil carbon stock
Authors: Zhang Bingquan , Guo Changqiang , Lin Tao , Faaij André P. C.
Published: February 2022

Environmental factors, including greenhouse gas (GHG) emissions and soil organic carbon (SOC), should be considered when building a sustainable biofuel supply chain. This work developed a three‐step optimization approach integrating a geographical information system‐based mixed‐integer linear programming model to economically optimize the biofuel supply chain on the premise of meeting certain GHG emission criteria. The biomass supply grid cell was considered first, based on a maximum level of GHG emissions, prior to economic optimization. The optimization simultaneously considered dual‐feedstock sourcing, selection between distributed and centralized configurations, and the impact of maintaining SOC balance in agricultural soil on biomass availability. The applicability of the modeling approach was demonstrated through a case study that optimized a dual‐feedstock renewable jet fuel supply chain via a gasification‐Fischer–Tropsch (gasification‐FT) conversion pathway in 2050 under three biomass availability scenarios. The case study results show that the differences in procurement costs and GHG emissions between energy crops and agricultural residues have a large impact on the layout of the supply chain. The supply‐chain configuration tends to be more centralized with large‐scale biorefineries when a supply region has an intensive and centralized distribution of biomass resources. The cost‐supply curves demonstrated the technical potential of biofuels that could be obtained at a certain level of cost. Additionally, sensitivity analysis shows that the GHG emission credit from producing extra electricity during the gasification‐FT process will be significantly reduced with a rising share of renewable electricity generation in the future. © 2022 The Authors. Biofuels, Bioproducts and Biorefining published by Society of Industrial Chemistry and John Wiley & Sons Ltd.