bluuebunny/crossref_metadata_2025 huggingface dataset:
Airway Surface Liquid Osmolality Measured Using Fluorophore-Encapsulated Liposomes
Authors: Jayaraman Sujatha , Song Yuanlin , Verkman A.S.
Published: July 2002

The airway surface liquid (ASL) is the thin layer of fluid coating the luminal surface of airway epithelial cells at an air interface. Its composition and osmolality are thought to be important in normal airway physiology and in airway diseases such as asthma and cystic fibrosis. The determinants of ASL osmolality include epithelial cell solute and water transport properties, evaporative water loss, and the composition of secreted fluids. We developed a noninvasive approach to measure ASL osmolality using osmotically sensitive 400-nm-diam liposomes composed of phosphatidylcholine/cholesterol/polyethylene glycol-phosphatidylcholine (1:0.3:0.08 molar ratio). Calcein was encapsulated in the liposomes at self-quenching concentrations (30 mM) as a volume-sensitive marker, together with sulforhodamine 101 (2 mM) as a volume-insensitive reference. Liposome calcein/sulforhodamine 101 fluorescence ratios responded rapidly (<0.2 s) and stably to changes in solution osmolality. ASL osmolality was determined from calcein/sulforhodamine 101 fluorescence ratios after addition of microliter quantities of liposome suspensions to the ASL. In bovine airway epithelial cells cultured on porous supports at an air–liquid interface, ASL thickness (by confocal microscopy) was 22 μm and osmolality was 325 ± 12 mOsm. In anesthetized mice in which a transparent window was created in the trachea, ASL thickness was 55 μm and osmolality was 330 ± 36 mOsm. ASL osmolality was not affected by pharmacological inhibition of CFTR in airway cell cultures or by genetic deletion of CFTR in knockout mice. ASL osmolality could be increased substantially to >400 mOsm by exposure of the epithelium to dry air; the data were modeled mathematically using measured rates of osmosis and evaporative water loss. These results establish a ratio imaging method to map osmolality in biological compartments. ASL fluid is approximately isosmolar under normal physiological conditions, but can become hyperosmolar when exposed to dry air, which may induce cough and airway reactivity in some patients.
Pkc-Mediated Stimulation of Amphibian Cftr Depends on a Single Phosphorylation Consensus Site. Insertion of This Site Confers Pkc Sensitivity to Human Cftr
Authors: Button Brian , Reuss Luis , Altenberg Guillermo A.
Published: July 2002

Mutations of the CFTR, a phosphorylation-regulated Cl− channel, cause cystic fibrosis. Activation of CFTR by PKA stimulation appears to be mediated by a complex interaction between several consensus phosphorylation sites in the regulatory domain (R domain). None of these sites has a critical role in this process. Here, we show that although endogenous phosphorylation by PKC is required for the effect of PKA on CFTR, stimulation of PKC by itself has only a minor effect on human CFTR. In contrast, CFTR from the amphibians Necturus maculosus and Xenopus laevis (XCFTR) can be activated to similar degrees by stimulation of either PKA or PKC. Furthermore, the activation of XCFTR by PKC is independent of the net charge of the R domain, and mutagenesis experiments indicate that a single site (Thr665) is required for the activation of XCFTR. Human CFTR lacks the PKC phosphorylation consensus site that includes Thr665, but insertion of an equivalent site results in a large activation upon PKC stimulation. These observations establish the presence of a novel mechanism of activation of CFTR by phosphorylation of the R domain, i.e., activation by PKC requires a single consensus phosphorylation site and is unrelated to the net charge of the R domain.
Structural and Functional Determinants of Conserved Lipid Interaction Domains of Inward Rectifying Kir6.2 Channels
Authors: Cukras Catherine A. , Jeliazkova Iana , Nichols Colin G.
Published: July 2002

All members of the inward rectifiier K+ (Kir) channel family are activated by phosphoinositides and other amphiphilic lipids. To further elucidate the mechanistic basis, we examined the membrane association of Kir6.2 fragments of KATP channels, and the effects of site-directed mutations of these fragments and full-length Kir6.2 on membrane association and KATP channel activity, respectively. GFP-tagged Kir6.2 COOH terminus and GFP-tagged pleckstrin homology domain from phospholipase C δ1 both associate with isolated membranes, and association of each is specifically reduced by muscarinic m1 receptor–mediated phospholipid depletion. Kir COOH termini are predicted to contain multiple β-strands and a conserved α-helix (residues ∼306–311 in Kir6.2). Systematic mutagenesis of D307-F315 reveals a critical role of E308, I309, W311 and F315, consistent with residues lying on one side of a α-helix. Together with systematic mutation of conserved charges, the results define critical determinants of a conserved domain that underlies phospholipid interaction in Kir channels.
Baire spaces and hyperspace topologies
Authors: Zsilinszky László
Published: July 2002

Sufficient conditions for abstract (proximal) hit-and-miss hyperspace topologies and the Wijsman hyperspace topology, respectively, are given to be Baire spaces, thus extending results of McCoy, Beer, and Costantini. Further the quasi-regularity of (proximal) hit-and-miss topologies is investigated.
Products on 𝑀𝑈-modules
Authors: Strickland N.
Published: July 2002

Elmendorf, Kriz, Mandell and May have used their technology of modules over highly structured ring spectra to give new constructions of

M
U

MU

-modules such as

B
P

BP

,

K
(
n
)

K(n)

and so on, which makes it much easier to analyse product structures on these spectra. Unfortunately, their construction only works in its simplest form for modules over

M
U
[

1
2

]
∗

MU[\frac {1}{2}]_*

that are concentrated in degrees divisible by

4
4

; this guarantees that various obstruction groups are trivial. We extend these results to the cases where

2
=
0

2=0

or the homotopy groups are allowed to be nonzero in all even degrees; in this context the obstruction groups are nontrivial. We shall show that there are never any obstructions to associativity, and that the obstructions to commutativity are given by a certain power operation; this was inspired by parallel results of Mironov in Baas-Sullivan theory. We use formal group theory to derive various formulae for this power operation, and deduce a number of results about realising

2
2

-local

M

U
∗

MU_*

-modules as

M
U

MU

-modules.
Generators and relations for Schur algebras
Authors: Doty Stephen , Giaquinto Anthony
Published: July 2002

We obtain a presentation of Schur algebras (and

q
q

-Schur algebras) by generators and relations, one which is compatible with the usual presentation of the enveloping algebra (quantized enveloping algebra) corresponding to the Lie algebra

g
l

n

\mathfrak {gl}_n

of

n
×
n

n\times n

matrices. We also find several new bases of Schur algebras.
Activation of p42 Mitogen-activated Protein Kinase (MAPK), but not c-Jun NH2-Terminal Kinase, Induces Phosphorylation and Stabilization of MAPK PhosphataseXCL100 inXenopusOocytes
Authors: Sohaskey Michael L. , Ferrell James E.
Published: July 2002

Dual-specificity protein phosphatases are implicated in the direct down-regulation of mitogen-activated protein kinase (MAPK) activity in vivo. Accumulating evidence suggests that these phosphatases are components of negative feedback loops that restore MAPK activity to low levels after diverse physiological responses. Limited information exists, however, regarding their posttranscriptional regulation. We cloned two Xenopus homologs of the mammalian dual-specificity MAPK phosphatases MKP-1/CL100 and found that overexpression of XCL100 in G2-arrested oocytes delayed or prevented progesterone-induced meiotic maturation. Epitope-taggedXCL100 was phosphorylated on serine during G2 phase, and on serine and threonine in a p42 MAPK-dependent manner during M phase. Threonine phosphorylation mapped to a single residue, threonine 168. Phosphorylation of XCL100 had no measurable effect on its ability to dephosphorylate p42 MAPK. Similarly, mutation of threonine 168 to either valine or glutamate did not significantly alter the binding affinity of a catalytically inactive XCL100 protein for active p42 MAPK in vivo. XCL100 was a labile protein in G2-arrested and progesterone-stimulated oocytes; surprisingly, its degradation rate was increased more than twofold after exposure to hyperosmolar sorbitol. In sorbitol-treated oocytes expressing a conditionally active ΔRaf-DD:ER chimera, activation of the p42 MAPK cascade led to phosphorylation of XCL100 and a pronounced decrease in the rate of its degradation. Our results provide mechanistic insight into the regulation of a dual-specificity MAPK phosphatase during meiotic maturation and the adaptation to cellular stress.
Discrete simulation of regulatory homo- and heterodimerization
in the apoptosis effector phase
Authors: Siehs Christian , Oberbauer Rainer , Mayer Gert , Lukas Arno , Mayer Bernd
Published: July 2002

Motivation: Quantitative simulation of molecular reaction networks is among the most promising approaches towards an understanding of complex biochemical pathways. Numerous qualitative as well as quantitative data from diverse experimental settings, in particular from genomics and proteomics, have to be contextually linked to convert static data into dynamic functionality.

Results: This paper presents the Lattice Molecular Automaton, a Cellular Automaton-based simulation tool, capable of representing complex molecular dynamics at different levels of granularity. A data structure concept represents molecular units, whose dynamics, embedded on a 2D grid, is defined via detailed intermolecular interaction profiles. The data structures hold diverse information as molecular type, potential, as well as kinetic energy states, which allows a precise representation of intracellular reaction networks. The molecular dynamics is performed via local computation of individual molecular states on the lattice, which, in conjunction with discretized space and time, enables excellent scalability of this simulation concept. This paper finally gives Lattice Molecular Automaton simulation results on key elements of apoptosis, the cell death cascade, in particular focusing on the regulatory function of homo- and heterodimerization of members of the Bcl-2 protein family in the apoptosis effector phase. The regulatory proteins Bcl2, Bax, and Bak constitute a diffusion-driven molecular switch with inherent damping of apoptosis induction, thereby controlling the apoptosis reaction cascade under noisy, external apoptosis inducing conditions.

Contact: bernd.mayer@univie.ac.at

* To whom correspondence should be addressed.
Population differentiation without speciation
Authors: Magurran Anne E.
Published: July 2002

Population differentiation is often viewed as an important step towards speciation, and part of the rationale for conserving variation at the intraspecific level is that the potential to generate more biological diversity should be retained. Yet, speciation is not an inevitable consequence of population divergence. This paper reviews recent work on the Trinidadian guppy,Poecilia reticulata, a species that is renowned for its capacity for population differentiation. Guppy populations evolve rapidly, within 10to 102generations, as a response to changes in selection exerted by predators. The rates of evolution involved can be up to seven orders of magnitude greater than those seen in the fossil record. Sexual selection, particuarly female choice, appears to reinforce the divergence that natural selection has generated. Perplexingly, however, there is no reproductive isolation (either prezygotic or postzygotic) between populations, even those that have been separated for at least 106generations. Sexual conflict may be the key to explaining this absence of speciation. Male reproductive behaviour, particularly the high incidence of sneaky mating, may be instrumental in producing sufficient gene flow to prevent reproductive isolation. Sneaky mating has the potential to undermine female choice, and is known to be an important means of sperm transfer in wild populations. Sexual dimorphism, also a result of sexual conflict in guppies, may inhibit speciation in another way. Morphological differences between the sexes, that have arisen for reproductive reasons, mean that males and females are pre–adapted for different foraging niches. This, in turn, reduces the opportunity for the development of feeding polymorphisms, a mechanism that seems to have been important in the sympatric speciation of other fish species.
Multiple kinetic components and the Ca2+ requirements of exocytosis
Authors: Kasai Haruo , Takahashi Noriko
Published: July 2002

The use of caged–Ca
2+
compounds to stimulate Ca
2+
–dependent exocytosis has substantially increased our understanding of this complex process. By this approach, the existence of multiple kinetic components of exocytosis has been established. These components may correspond to a series of sequential steps that lead to a single fusion–ready state (sequential mechanism) or, alternatively, to heterogeneity in secretory vesicles or in fusion–ready states (parallel mechanism). It is suggested that both of these mechanisms can underlie exocytosis of a single type of vesicle (mixed sequential–parallel mechanism). Studies with caged–Ca
2+
compounds have also indicated that the Ca
2+
requirement for exocytosis is substantially greater than that suggested by conventional methodologies. This discrepancy is mainly attributable to the underestimation, by imaging studies with high–affinity Ca
2+
indicators (due to dye saturation), of the local increases in cytosolic Ca
2+
concentration that trigger the exocytosis of individual vesicles. The effects of local saturation of such indicators are explored by means of a simple theory.
Hair cell heterogeneity and ultrasonic hearing: recent advances in understanding fish hearing
Authors: Popper Arthur N.
Published: July 2002

The past decade has seen a wealth of new data on the auditory capabilities and mechanisms of fishes. We now have a significantly better appreciation of the structure and function of the auditory system in fishes with regard to their peripheral and central anatomy, physiology, behaviour, sound source localization and hearing capabilities. This paper deals with two of the newest of these findings, hair cell heterogeneity and the detection of ultrasound. As a result of this recent work, we now know that fishes have several different types of sensory hair cells in both the ear and lateral line and there is a growing body of evidence to suggest that these hair cell types arose very early in the evolution of the octavolateralis system. There is also some evidence to suggest that the differences in the hair cell types have functional implications for the way the ear and lateral line of fishes detect and process stimuli. Behavioural studies have shown that, whereas most fishes can only detect sound to 1–3 kHz, several species of the genus Alosa (Clupeiformes, i.e. herrings and their relatives) can detect sounds up to 180 kHz (or even higher). It is suggested that this capability evolved so that these fishes can detect one of their major predators, echolocating dolphins. The mechanism for ultrasound detection remains obscure, though it is hypothesized that the highly derived utricle of the inner ear in these species is involved.
δ -function converging sequences
Authors: Aguirregabiria J. M. , Hernández A. , Rivas M.
Published: July 2002

We discuss the usefulness and physical interpretation of a simple and general way of constructing sequences of functions that converge to the Dirac delta function. The main result, which seems to have been largely overlooked, includes most of the δ-function converging sequences found in textbooks, is easily extended, and can be used to introduce many useful generalized functions to physics students with little mathematical background. We show that some interesting delta-function identities are simple consequences of the one discussed here. An illustrative example in electrodynamics is also analyzed, with the surprising result that the formalism allows as a limit an uncharged massless particle which creates no electromagnetic field, but has a nonzero electromagnetic energy–momentum tensor.
Quantitative measures of hair cell loss in CBA and C57BL/6 mice throughout their life spans
Authors: Spongr Vlasta P. , Flood Dorothy G. , Frisina Robert D. , Salvi Richard J.
Published: July 2002

The CBA mouse shows little evidence of hearing loss until late in life, whereas the C57BL/6 strain develops a severe and progressive, high-frequency sensorineural hearing loss beginning around 3–6 months of age. These functional differences have been linked to genetic differences in the amount of hair cell loss as a function of age; however, a precise, quantitative description of the sensory cell loss is unavailable. The present study provides mean values of inner hair cell (IHC) and outer hair cell (OHC) loss for CBA and C57BL/6 mice at 1, 3, 8, 18, and 26 months of age. CBA mice showed little evidence of hair cell loss until 18 months of age. At 26 months of age, OHC losses in the apex and base of the cochlea were approximately 65% and 50%, respectively, and IHC losses were approximately 25% and 35%. By contrast, C57BL/6 mice showed approximately a 75% OHC and a 55% IHC loss in the base of the cochlea at 3 months of age. OHC and IHC losses increased rapidly with age along a base-to-apex gradient. By 26 months of age, more than 80% of the OHCs were missing throughout the entire cochlea; however, IHC losses ranged from 100% near the base of the cochlea to approximately 20% in the apex.
Analysis of annoyance of low-frequency beat inside a vehicle
Authors: Genuit Klaus
Published: July 2002

Because station wagons have a greater volume than sedan vehicles, low-frequency acoustic effects (‘‘humming’’) very often occur in the frequency range between 30 and 50 Hz. This is not only unpleasant, but can lead to physiological changes in the driver due to specific properties of the acoustic signals. The mechanisms may be very varied: Excitation frequencies can be produced by the powertrain, exhaust system, or wheel suspension and are transmitted via the mounting points. Resonances in the regarded frequency range may well be present along these transmission paths. The spectral components thus arriving at the structure are radiated into the car interior via various ‘‘loudspeakers,’’ such as floor panels, roofs, or doors. Moreover, for particular frequencies some loudspeakers may show special resonances or the volume of the vehicle interior results in amplification. During field trials, excitation mechanisms and transmission paths were investigated using the combination of Artificial Head and multichannel measurement technology that allows subjective evaluation of various models. Playback of the Artificial Head signals, however, is not only via headphones, but via a special ‘‘sound car’’ which also creates low-frequency excitation of airborne and structure-borne noise. This enables a connection to be made between the frequencies at the driver’s ear giving cause for complaint and the various excitation points. Moreover, the use of a two-dimensional laser vibrometer enables a connection to be made between vibrating structures and the annoying sound components a driver is hearing.
A new theoretical approach to the analysis of nonlinear sound beams using the oblate spheroidal coordinate system
Authors: Kamakura Tomoo , Ishiwata Tsuneo , Matsuda Kazuhisa
Published: July 2002

In this article, the authors propose a new model equation which describes well progressive sound beams from a planar piston source with a circular aperture. The theory is based on the oblate spheroidal coordinate system and is easily extended to the analysis of nonlinear propagation of finite amplitude sound beams. The resultant beam equation facilitates numerical calculations in the far field. An experiment is performed in water using a 5-MHz planar ultrasonic transducer with a 9-mm radius aperture, and the results are compared with the theoretical prediction for sound pressure amplitudes of the fundamental and second harmonics. They are in excellent agreement with each other along and across the beam axis.
Acquisition of second language intonation
Authors: Jun Sun-Ah , Oh Mira
Published: July 2002

Foreign accents in second language (L2) production are caused by the phonological system and phonetic realization of the first language (L1), including both segmental and prosodic features. This paper examines the intonation structure of Seoul Korean and its realization by American English speakers. Four English speakers of Korean, differing in fluency, and two Korean speakers participated. Thirty-six sentences were designed to test the realization of prosodic structure, focus, and intonation patterns by varying the number of syllables within a word and a sentence, and conditions for the segment–tone interaction. Preliminary results show that, as in segmental data, more advanced L2 speakers produced more nativelike intonation pattern and prosodic structure than less advanced ones. Advanced L2 speakers were better in grouping words into phrases and producing the phrase-final high tone than less advanced speakers, but they still produced English-like pitch accents following English stress rules, suggesting that a lexically linked prosodic feature is hard to suppress. In addition, less advanced L2 speakers more often produced each word in one intonation phrase, reflecting a limitation of information processing as found in L1 acquisition. Finally, more advanced speakers distinguished the segmentally triggered tones better than less advanced speakers but with large variation.
Rheology of Concentrated Suspensions of Fibers in Tube Flow. II. An Exploratory Study
Authors: Maschmeyer Richard O. , Hill Christopher T.
Published: July 2002

The viscosities of concentrated suspensions of glass fibers in high viscosity silicone oils were measured with a 14″ capillary viscometer. Suspensions were mixed by various techniques, but only data for extruder mixed suspensions are presented. All pertinent suspension parameters were monitored, including wall effects. Yield stresses, squeeze-through, and capillary entrance exclusion were observed. Both the quantitative and qualitative aspects of fiber suspension rheology depended strongly on fiber length, which is consistent with the variety of behavior reported in the literature. Controlling fiber length independent of changes in other suspension parameters is difficult.
Kinetics of biopolymer gelation—Implications of a cascade theory description for the concentration, molecular weight, and temperature dependences of the shear modulus and gel time
Authors: Clark A. H. , Farrer D. B.
Published: July 2002

The kinetic progress of biopolymer gelation is measured in terms of the shear modulus–time curve available from mechanical spectroscopy. Attention is focused on the gel time, and on the limiting value of the modulus attained at long time. A theoretical treatment of these quantities is presented based on cascade theory. This model can take on a reversible, or irreversible, form depending on differential equations defining the growth of the degree of cross-linking α(t), i.e., depending on whether a crosslink equilibrium is assumed or permanent branched crosslinking competes with irreversible intramolecular cyclization. Application of this model to limiting modulus–concentra- tion and modulus–temperature data is illustrated using results for a low DE pectin–calcium system. The model’s ability to explain modulus–molecular weight data is also demonstrated using literature data for kappa carrageenan gels. Where gel time–concentration data are concerned, success is much more limited, however, and this problem is discussed.
Rheology of a viscoelastic emulsion with a liquid crystalline polymer dispersed phase
Authors: Lee Heon Sang , Denn Morton M.
Published: July 2002

The steady-shear viscosity and first normal stress difference and the dynamic storage and loss moduli have been measured for a blend consisting of a thermotropic liquid crystalline polymer dispersed in a thermoplastic fluoropolymer matrix. The components are immiscible and nonreacting. Consistency with the Palierne emulsion theory for viscoelastic blends is possible if and only if the interfacial tension contribution is negligible for droplets that are comparable in size to a liquid crystalline domain or smaller, while retaining the effect for larger droplets. Steady shear results are approximately described by the scaling of the Doi–Ohta theory, but there is a significant reduction in the excess shear stress over a finite shear-rate range for the lowest concentration, which contains the smallest droplets.
Isotretinoin Laboratory Monitoring in Acne Treatment
Authors: Xia Eric , Han Jane , Faletsky Adam , Baldwin Hilary , Beleznay Katie , Bettoli Vincenzo , Dréno Brigitte , Goh Chee Leok , Stein Gold Linda , Gollnick Harald , Herane Maria Isabel , Kang Sewon , Kircik Leon , Mann Julianne , Nast Alexander , Oon Hazel H. , See Jo Ann , Tollefson Megha , Webster Guy , Zip Catherine , Tan Jerry , Tapper Elliot B. , Thiboutot Diane , Zaenglein Andrea , Barbieri John , Mostaghimi Arash
Published: June 2022

Importance

Although isotretinoin may rarely be associated with laboratory abnormalities such as hypertriglyceridemia, the optimal approach to laboratory monitoring is uncertain, and there is wide variation in clinical practice.

Objective

To establish a consensus for isotretinoin laboratory monitoring among a diverse, international cohort of clinical and research experts in acne.

Design, Setting, and Participants

Using a modified electronic Delphi process, 4 rounds of anonymous electronic surveys were administered from 2021 to 2022. For laboratory tests reaching consensus (≥70% agreement) for inclusion, questions regarding more time-specific monitoring throughout isotretinoin therapy were asked in subsequent rounds. The participants were international board-certified dermatologist acne experts who were selected on a voluntary basis based on involvement in acne-related professional organizations and research.

Main Outcomes and Measures

The primary outcome measured was whether participants could reach consensus on key isotretinoin laboratory monitoring parameters.

Results

The 22 participants from 5 continents had a mean (SD) time in practice of 23.7 (11.6) years and represented a variety of practice settings. Throughout the 4-round study, participation rates ranged from 90% to 100%. Consensus was achieved for the following: check alanine aminotransferase within a month prior to initiation (89.5%) and at peak dose (89.5%) but not monthly (76.2%) or after treatment completion (73.7%); check triglycerides within a month prior to initiation (89.5%) and at peak dose (78.9%) but not monthly (84.2%) or after treatment completion (73.7%); do not check complete blood cell count or basic metabolic panel parameters at any point during isotretinoin treatment (all >70%); do not check gamma-glutamyl transferase (78.9%), bilirubin (81.0%), albumin (72.7%), total protein (72.7%), low-density lipoprotein (73.7%), high-density lipoprotein (73.7%), or C-reactive protein (77.3%).

Conclusions and Relevance

This Delphi study identified a core set of laboratory tests that should be evaluated prior to and during treatment with isotretinoin. These results provide valuable data to guide clinical practice and clinical guideline development to optimize laboratory monitoring in patients treated with isotretinoin.
Polymer Colloids
Authors: Tangboriboonrat Pramuan , Sunintaboon Panya , Chaiyasat Amorn , Chaiyasat Preeyaporn
Published: June 2022

This article illustrates a comprehensive overview of polymer colloids in various aspects, including background, importance and preparation methods to fine‐tune their properties, particle morphology, particle analysis, and examples of their applications. For the preparation of polymer colloids, two general classifications, (heterogeneous) polymerization starting from monomers and nonpolymerization methods using preformed polymers as raw materials, are presented. A wide variety of preparation methods mainly based on emulsion polymerization including microemulsion and miniemulsion are given. Features of these methods and characteristics of polymer colloids obtained are also described. In fact, process operations influence the properties of polymer colloids, for example, copolymer composition, molecular weight distribution, polymer architecture, particle morphology, and particle size distribution. Thus, a summary of those process operations, that is, batch, semibatch, semicontinuous, and continuous processes, is included. Since particle morphology is of great importance for determining their properties and making them useful in a broad range of applications, the design and engineering for diversified types of structured particle are emphasized and related to their applications. Common analytical methods for particle analysis are included.
Comparison of Eclipse Smart Segmentation and MIM Atlas Segment for liver delineation for yttrium‐90 selective internal radiation therapy
Authors: Li Jun , Anne Rani
Published: June 2022

Purpose

The aim was to compare Smart Segmentation of Eclipse treatment planning system and Atlas Segment of MIM software for liver delineation for resin yttrium‐90 (Y‐90) procedures.

Materials and methods

CT images of 20 patients treated with resin Y‐90 selective internal radiation therapy (SIRT) were tested. Liver contours generated with Smart Segmentation and Atlas Segment were compared with physician manually delineated contours. Dice similarity coefficient (DSC), mean distance to agreement (MDA), and ratio of volume (RV) were calculated. The contours were evaluated with activity calculations and ratio of activity (RA) was calculated.

Results

Mean DSCs were 0.77 and 0.83, MDAs were 0.88 and 0.71 cm, mean RVs were 0.95 and 1.02, and mean RAs were 1.00 and 1.00, for Eclipse and MIM results, respectively.

Conclusion

MIM outperformed Eclipse in both DSC and MDA, whereas the differences in liver volumes and calculated activities were statistically insignificant between the Eclipse and MIM results. Both auto‐segmentation tools can be used to generate initial liver contours for resin Y‐90 SIRT, which need to be reviewed and edited by physicians.
Ultrasensitive Solar‐Blind Ultraviolet Photodetector Based on FePSe3/MoS2 Heterostructure Response to 10.6 µm
Authors: Long Mingsheng , Shen Zhen , Wang Ruijie , Dong Qingsong , Liu Zhiyi , Hu Xin , Hou Jie , Lu Yuan , Wang Fang , Zhao Dongxu , Ding Fei , Tu Yubing , Han Tao , Li Feng , Zhang Zongyuan , Hou Xingyuan , Wang Shaoliang , Shan Lei
Published: June 2022

Metal phosphorous tri‐chalcogenides are a category of new ternary 2D layered materials with a wide range of tuneable bandgaps (1.2–3.5 eV). These wide‐bandgap semiconductors exhibit great potential applications in solar‐blind ultraviolet (SBUV) photodetection. However, these 2D solar‐blind photodetectors suffer from low photoresponsivity, slow photoresponse speed, and narrow operation spectral region, thereby limiting their practical applications. Here, an ultra‐broadband photodetection based on a FePSe3/MoS2 heterostructure with coverage ranging from solar‐blind ultraviolet 265 nm to longwave infrared (LWIR) 10.6 µm is reported. Notably, the device exhibits excellent weak light detection capability. A high photoresponsivity of 33 600 A W−1 and an external quantum efficiency of 1.57 × 107% are demonstrated. A noise‐equivalent power as low as 5.7 ×  10–16 W Hz−1/2 and a specific detectivity up to 1.51 × 1013 cm Hz1/2 W−1 are realized in the SBUV region. The room temperature LWIR photoresponsivity of 0.12 A W−1 is realized. This work opens a route to design high‐performance SBUV photodetectors and wide spectral photoresponse applications.
High‐Performance Biomechanical Energy Harvester Enabled by Switching Interfacial Adhesion via Hydrogen Bonding and Phase Separation
Authors: Wang Lingyun , Wang Yu , Bo Xiangkun , Wang Haoyu , Yang Su , Tao Xiaoming , Zi Yunlong , Yu William W. , Li Wen Jung , Daoud Walid A.
Published: June 2022

Dramatic advances in wearable electronics have triggered tremendous demands for wearable power sources. To mitigate the impact of CO2 emission on the environment caused by energy consumption, biomechanical energy harvesting for self‐powered wearable electronics offers a promising solution. The output power of devices largely relies on the surface charge density, where adhesion interfaces generate a higher amount than nonadhesion counterparts, yet unfavorable for wearable devices due to the large detachment force required. Thus, sustaining high surface charge density in an adhesion‐free interface represents a major challenge. Herein, by leveraging intermolecular interactions and solvent evaporation induced phase separation, a nonadhesion interface is successfully realized, minimizing the interfacial adhesion from 20 to 0 kPa. Importantly, benefiting from the induced nano/microscale topography upon phase separation, comparable surface charges are generated at the interface. Consequently, a high‐performance flexible biomechanical energy harvester featuring a record high peak power density of 20.5 W m‐2 Hz‐1 at low matching impedance of 1 MΩ is achieved under a low biomechanical input force of 5 N. The device can power small electronics by harvesting regular or intermittent biomechanical energy and illuminate light‐emitting diodes wired/wirelessly. This work provides a facile strategy for interfacial engineering toward efficient energy harvesting.
Nonlinear Computational Edge Detection Metalens
Authors: Zhou Junxiao , Zhao Junxiang , Wu Qianyi , Chen Ching‐Fu , Lei Ming , Chen Guanghao , Tian Fanglin , Liu Zhaowei
Published: June 2022

Optical image processing and computing systems provide supreme information processing rates by utilizing parallel optical architectures. Existing optical analog processing techniques require multiple devices for projecting images and executing computations. In addition, those devices are typically limited to linear operations due to the time‐invariant optical responses of the building materials. In this work, a single metalens with an illumination intensity dependent coherent transfer function (CTF) is proposed and experimentally demonstrated, which performs varying computed imaging without requiring any additional optical components. The metalens consisting of nanoantenna structures with a static geometric phase and a nonlinear metallic quantum well layer offering an intensity‐dependent dynamic phase results in a continuously tunable CTF. The approach allows for a weighted summation of two designed functions based on the metalens design, which potentially enables all optical computations of complex functions. The nonlinear metalens may lead to important applications in optical neural networks and parallel analog computing.
Deep Learning Assisted Body Area Triboelectric Hydrogel Sensor Network for Infant Care
Authors: Guo Rui , Fang Yunsheng , Wang Zhaosu , Libanori Alberto , Xiao Xiao , Wan Dong , Cui Xiaojing , Sang Shengbo , Zhang Wendong , Zhang Hulin , Chen Jun
Published: June 2022

Infants are physically vulnerable and cannot express their feelings. Continuous monitoring and measuring the biomechanical pressure to which an infant body is exposed remains critical to avoid infant injury and illness. Here, a body area sensor network comprising edible triboelectric hydrogel sensors for all‐around infant motion monitoring is reported. Each soft sensor holds a collection of compelling features of high signal‐to‐noise ratio of 23.1 dB, high sensitivity of 0.28 V kPa−1, and fast response time of 50 ms. With the assistance of deep learning algorithms, the body area sensor network can realize infant motion pattern identification and recognition with classification accuracy as high as 100%. Additionally, a customized user‐friendly cellphone application is developed to provide real‐time warning and one‐click guardian interaction. This self‐powered body area sensor network system provides a promising paradigm for reliable infant care in the era of the Internet of Things.
Unraveling Device Physics of Dilute‐Donor Narrow‐Bandgap Organic Solar Cells with Highly Transparent Active Layers
Authors: Schopp Nora , Akhtanova Gulnur , Panoy Patchareepond , Arbuz Alexandr , Chae Sangmin , Yi Ahra , Kim Hyo Jung , Promarak Vinich , Nguyen Thuc‐Quyen , Brus Viktor V.
Published: June 2022

The charge generation–recombination dynamics in three narrow‐bandgap near‐IR absorbing nonfullerene (NFA) based organic photovoltaic (OPV) systems with varied donor concentrations of 40%, 30%, and 20% are investigated. The dilution of the polymer donor with visible‐range absorption leads to highly transparent active layers with blend average visible transmittance (AVT) values of 64%, 70%, and 77%, respectively. Opaque devices in the optimized highly reproducible device configuration comprising these transparent active layers lead to photoconversion efficiencies (PCEs) of 7.0%, 6.5%, and 4.1%. The investigation of these structures yields quantitative insights into changes in the charge generation, non‐geminate charge recombination, and extraction dynamics upon dilution of the donor. Lastly, this study gives an outlook for employing the highly transparent active layers in semitransparent organic photovoltaics (ST‐OPVs).
Defect‐Engineered Magnetic Field Dependent Optoelectronics of Vanadium Doped Tungsten Diselenide Monolayers
Authors: Nisi Katharina , Kiemle Jonas , Powalla Lukas , Scavuzzo Alessio , Nguyen Tuan Dung , Taniguchi Takashi , Watanabe Kenji , Duong Dinh Loc , Burghard Marko , Holleitner Alexander W. , Kastl Christoph
Published: June 2022

The ability to dope transition metal dichalcogenides such as tungsten diselenide (WSe2) with magnetic transition metal atoms in a controlled manner has motivated intense research with the aim of generating dilute magnetic semiconductors. In this work, semiconducting WSe2 monolayers, substitutionally doped with vanadium atoms, are investigated using low‐temperature luminescence and optoelectronic spectroscopy. V‐dopants lead to a p‐type doping character and an impurity‐related emission ≈160 meV below the neutral exciton, both of which scale with the nominal percentage of V‐dopants. Measurements using field‐effect devices of 0.3% V‐doped WSe2 demonstrate bipolar carrier tunability. The doped monolayers display a clear magnetic hysteresis in transport measurements both under illumination and without illumination, whereas the valley polarization of the excitons reveals a nonlinear g‐factor without a magnetic hysteresis within the experimental uncertainty. Hence, this work on V‐doped WSe2 provides crucial insights concerning suitable characterization methods on magnetic properties of doped 2D materials.
Fine‐Tuning Single‐Source White‐Light Emission from All‐Inorganic Corrugated 2D Antimony‐Halide Perovskite
Authors: Xu Fei , Wang Xiang , Li Yue , Jiang Beng , Dong Zuoru , Yang Zichen , Kang Jiaxing , Shu Xin , Jiang Zuimin , Hong Feng , Xu Run , Ma Zhongquan , Chen Teng , Xu Zhan , Xu Haitao
Published: June 2022

Corrugated 2D antimony‐halide perovskites such as Cs3Sb2Cl9 (CSC) are promising candidates for single‐source white‐light emission due to their ultra‐broadband spectra. However, CSC has a serious luminescence quenching phenomenon due to inadequate confinement of excitons. By the homovalent substitution of trivalent antimony cation Sb3+ by a small amount of trivalent rare earth (RE) cations RE3+, the photoluminescence intensities from high‐quality Cs3(Sb1−xREx)2Cl9 (CSRC) (RE = Ce, Sm, Nd, Y, Er, etc.) films at room temperature (RT) are over two orders of magnitude higher than that of CSC film. Especially, the photoluminescence quantum yield (PLQY) for the Cs3(Sb0.995Er0.005)2Cl9 film is 9.5% at RT, which is much higher than A3B2X9 perovskites previously reported for single‐source white‐light lighting. Furthermore, the Cs3(Sb0.995Er0.005)2Cl9 film exhibits an ultra‐broadband emission with the full width at half maximum reaching 554 meV at RT, resulting in a “warm” white‐light with the CIE coordinate (0.33, 0.46) and the correlated color temperature of 5450 K. The PLQY enhancement can be considered as the fact that a high activation energy by bandgap widening effect and Type‐I‐like “straddling” band alignment between Cs3Sb2Cl9 and Cs3Er2Cl9 lead to reducing nonradiative losses and increasing radiative recombination channels. Meanwhile, the spectral broadening can be considered to be attributed to strong effect of electron–phonon interaction.
Dual Functional Dopant‐Free Contacts with Titanium Protecting Layer: Boosting Stability while Balancing Electron Transport and Recombination Losses
Authors: Liu Zhaolang , Lin Hao , Wang Zilei , Chen Liyan , Wu Taojian , Pang Yicong , Cai Lun , He Jian , Peng Shanglong , Shen Hui , Gao Pingqi
Published: June 2022

Combining electron‐ and hole‐selective materials in one crystalline silicon (Si) solar cell, thereby avoiding any dopants, is not considered for application to photovoltaic industry until only comparable efficiency and stable performance are achievable. Here, it is demonstrated how a conventionally unstable electron‐selective contact (ESC) is optimized with huge boost in stability as well as improved electron transport. With the introduction of a Ti thin film between a‐Si:H(i)/LiF and Al electrode, high‐level passivation (Seff = 4.6 cm s–1) from a‐Si:H(i) and preferential band alignment (ρC = 7.9 mΩ cm2) from low work function stack of LiF/Ti/Al are both stably retained in the newly constructed n‐Si/a‐Si:H(i)/LiF/Ti/Al ESC. A detailed interfacial elements analysis reveals that the efficiently blocked inward diffusion of Al from electrode by the Ti protecting layer balances transport and recombination losses in general. This excellent electron‐selective properties in combination with large process tolerance that enable remarkable device performance, particularly high efficiencies of 22.12% and 23.61%, respectively, are successfully approached by heterojunction solar cells with dopant‐free ESC and dopant‐free contacts for both polarities.
Bridging Multiscale Characterization Technologies and Digital Modeling to Evaluate Lithium Battery Full Lifecycle
Authors: Liu Xinhua , Zhang Lisheng , Yu Hanqing , Wang Jianan , Li Junfu , Yang Kai , Zhao Yunlong , Wang Huizhi , Wu Billy , Brandon Nigel P. , Yang Shichun
Published: June 2022

The safety, durability and power density of lithium‐ion batteries (LIBs) are currently inadequate to satisfy the continuously growing demand of the emerging battery markets. Rapid progress has been made from material engineering to system design, combining experimental results and simulations to enhance LIB performance. Limited by spatial and temporal resolution, state‐of‐the‐art advanced characterization techniques fail to fully reveal the complex multi‐scale degradation mechanism in LIBs. Strengthening interaction and iteration between characterization and modeling improves the understanding of reaction mechanisms as well as design and management of LIBs. Herein, a seed cyber hierarchy and interactional network framework is demonstrated to evaluate the overall lifecycle of LIBs. The typical examples of bridging the characterization techniques and modeling are discussed. The critical parameters extracted from multi‐scale characterization can serve as digital inputs for modeling. Furthermore, advanced computational techniques including cloud computing, big data, machine learning, and artificial intelligence can also promote the comprehensive understanding and precise control of the whole battery lifecycle. Digital twins techniques will be introduced enabling the real‐time monitoring and control of LIBs, autonomous computer‐assisted characterizations and intelligent manufacturing. It is anticipated that this work will provide a roadmap for further intensive research on developing high‐performance LIBs and intelligent battery management.
A dynamic 3‐factor survival model for acute myeloid leukemia that accounts for response to induction chemotherapy
Authors: Tefferi Ayalew , Gangat Naseema , Al‐Kali Aref , Alkhateeb Hassan , Shah Mithun , Patnaik Mrinal S. , Elliott Michelle A. , Hogan William J. , Litzow Mark R. , Hook Christopher C. , Mangaonkar Abhishek , Viswanatha David , Chen Dong , Pardanani Animesh , Ketterling Rhett P. , DiNardo Courtney D. , Kadia Tapan M. , Ravandi Farhad , Sasaki Koji , Begna Kebede H.
Published: June 2022

The current study was approached with the assumption that response to induction chemotherapy, in acute myeloid leukemia (AML), overshadows pre‐treatment risk variables in predicting survival and therefore be used as an anchor for a simplified risk model. We considered 759 intensively‐treated patients with AML, not promyelocytic: median age 60 years; primary 66%, secondary 25%, and therapy‐related 9%; European LeukemiaNet cytogenetic risk category favorable 8%, intermediate 61%, and adverse 31%. Complete remission with (CR) or without (CRi) count recovery was achieved in 608 (80%) patients. After a median follow‐up of 22 months, 503 deaths, 272 relapses, and 257 allogeneic hematopoietic stem cell transplants (AHSCTs) were recorded. Multivariable analysis identified failure to achieve CR/CRi (HR 3.8, 95% CI 3.1–4.8), adverse karyotype (2.2, 1.8–2.8), and age >55 years (2.1, 1.6–2.7) as main risk factors for survival. HR‐weighted scoring resulted in four‐tiered risk stratification: low (0 points; N = 183), intermediate‐1 (1 point; N = 331), intermediate‐2 (2 points; N = 117), and high (≥3 points; N = 128), with respective median survival (5‐year rate) not reached (68%), 34 (37%), 13 (20%), and 5 (5%) months (p < .001). FLT3‐ITD mutation was associated with inferior survival in intermediate‐1 (p = .004) and TP53 in intermediate‐2 (p = .06) and high (p = .02) risk disease; the latter was fully accounted for by the close association between TP53 mutation and complex/monosomal karyotype while the observations regarding FLT3‐ITD were not affected by treatment with midostaurin. AHSCT had a favorable impact on survival, most apparent in intermediate‐1 (p < .001), intermediate‐2 (p = .03), and high (p = .01) risk disease. The proposed 3‐factor survival model offers a novel prototype that is amenable to further enhancement by molecular information and was validated in an external cohort of 1032 intensively‐treated AML patients.