Heterogeneous lattice strain strengthening in severely distorted crystalline solids.

Multi-principal element alloys (MPEAs) exhibit outstanding mechanical properties because the core effect of severe atomic lattice distortion is distinctly different from that of traditional alloys. However, at the mesoscopic scale the underlying physics for the abundant dislocation activities responsible for strength-ductility synergy has not been uncovered. While the Eshelby mean-field approaches become insufficient to tackle yielding and plasticity in severely distorted crystalline solids, here we develop a three-dimensional discrete dislocation dynamics simulation approach by taking into account the experimentally measured lattice strain field from a model FeCoCrNiMn MPEA to explore the heterogeneous strain-induced strengthening mechanisms. Our results reveal that the heterogeneous lattice strain causes unusual dislocation behaviors (i.e., multiple kinks/jogs and bidirectional cross slips), resulting in the strengthening mechanisms that underpin the strength-ductility synergy. The outcome of our research sheds important insights into the design of strong yet ductile distorted crystalline solids, such as high-entropy alloys and high-entropy ceramics.

New Insight into Bulk Structural Degradation of High-Voltage LiCoO2 at 4.55 V.

The aggravated mechanical and structural degradation of layered oxide cathode materials upon high-voltage charging invariably causes fast capacity fading, but the underlying degradation mechanisms remain elusive. Here we report a new type of mechanical degradation through the formation of a kink band in a Mg and Ti co-doped LiCoO2 cathode charged to 4.55 V (vs Li/Li+). The local stress accommodated by the kink band can impede crack propagation, improving the structural integrity in a highly delithiated state. Additionally, machine-learning-aided atomic-resolution imaging reveals that the formation of kink bands is often accompanied by the transformation from the O3 to O1 phase, which is energetically favorable as demonstrated by first-principles calculations. Our results provide new insights into the mechanical degradation mechanism of high-voltage LiCoO2 and the coupling between electrochemically triggered mechanical failures and structural transition, which may provide valuable guidance for enhancing the electrochemical performance of high-voltage layered oxide cathode materials for lithium-ion batteries.

Archaeal Kink-Turn Binding Protein Mediates Inhibition of Orthomyxovirus Splicing Biology.

Despite lacking a DNA intermediate, orthomyxoviruses complete their replication cycle in the nucleus and generate multiple transcripts by usurping the host splicing machinery. This biology results in dynamic changes of relative viral transcripts over time and dictates the replicative phase of the infection. Here, we demonstrate that the family of archaeal L7Ae proteins uniquely inhibit the splicing biology of influenza A virus, influenza B virus, and Salmon isavirus, revealing a common strategy utilized by Orthomyxoviridae members to achieve this dynamic. L7Ae-mediated inhibition of virus biology was lost with the generation of a splicing-independent strain of influenza A virus and attempts to select for an escape mutant resulted in variants that conformed to host splicing biology at significant cost to their overall fitness. As L7Ae recognizes conventional kink turns in various RNAs, these data implicate the formation of a similar structure as a shared strategy adopted by this virus family to coordinate their replication cycle. IMPORTANCE Here, we demonstrate that a family of proteins from archaea specifically inhibit this splicing biology of all tested members of the Orthomyxoviridae family. We show that this inhibition extends to influenza A virus, influenza B virus, and isavirus genera, while having no significant impact on the mammalian transcriptome or proteome. Attempts to generate an escape mutant against L7Ae-mediated inhibition resulted in mutations surrounding the viral splice sites and a significant loss of viral fitness. Together, these findings reveal a unique biology shared among diverse members of the Orthomyxoviridae family that may serve as a means to generate future universal therapeutics.

Deformed Popliteal Artery Due to Highly Flexed Knee Position Can Cause Kinks, Creating an Unfavorable Hemodynamic State.

BACKGROUND: Endovascular treatment devices of the femoropopliteal artery have evolved, improving clinical results. However, the effects of dynamic changes in the popliteal artery during knee flexion have not been sufficiently investigated. In this study we performed a 3-dimensional analysis to clarify the dynamic changes in the popliteal artery during knee flexion and their effects on hemodynamics.Methods and Results: To analyze dynamic changes in the popliteal artery in the knee flexion position, a computed tomography protocol was developed in the right-angled and maximum flexion knee positions. Thirty patients with lower extremity artery disease were recruited. V-Modeler software was used for anatomical and hemodynamic analyses. Various types of deformations of the popliteal artery were revealed, including hinge points and accessory flexions. Kinks can occur in the maximum flexion position; however, they rarely occur in the right-angled flexion position. In addition, hemodynamic analysis revealed a tendency for lower minimum wall shear stress and a higher maximum oscillatory shear index at the maximum curvature of the popliteal artery. CONCLUSIONS: Kinks in the maximum flexion position suggested that the outcome of endovascular treatment may change in areas such as Japan, where knee flexion is customary. Hemodynamics at the maximum curvature of the popliteal artery indicated that the luminal condition was unfavorable for endovascular treatment.

The direct and spillover effects of diabetes diagnosis on lifestyle behaviours.

Using blood sample data we exploit an arbitrary cut-off of diabetes risk and through a fuzzy regression kink design we estimate the effect of a diabetes diagnosis on own and partner health-related behaviours. Diabetes diagnosis increases the probability of exercising, both for those diagnosed with diabetes and their partner. We also conduct mediation analysis which suggests that joint household participation is the channel behind this effect. Our results have significant implications for the understanding of the channels that induce behavioural change, and household decision making, as well as, for the evaluation of diabetes related policies.

Explanations for Gender Differences in Preferences for Submissive Sexual Fantasies.

Women have a stronger preference for sexual submission than men do. In the current studies, we investigated gender differences in fantasies about sexual submission. Replicating previous research, in two studies we found that women expressed a stronger affinity for fantasies about sexual submission than men did. However, controlling for age and several sociocultural factors made the relationship between gender and preference for sexual submission non-significant-that is, we could statistically eliminate the gender difference. These analyses suggest the multiple factors that may influence sexual preferences and the multiple ways that gender differences in preference for submissive sexual fantasies can be eliminated by easily assessed demographic and contextual differences in the experiences of women and men.

Heat Flow Guiding and Modulation by Kinks in a Silicon Nanoribbon.

Tailoring heat flow in solids has profound implications for the innovation of functional thermal devices. However, the current methods face technological challenges related to system complexity, material stability, and operating temperature. In this study, we demonstrated efficient heat flow modulation in a single material without a phase transition, using a simple and entirely material-independent strategy, kinked nanostructure patterning, at near-ambient temperature. By carefully controlling the kink arm length and kink angle of the Si nanoribbons, we achieved a thermal conductivity modulation of up to ∼20%. Our theoretical modeling showed that this modulation results from the competing roles of phonon backscattering and open view channels on heat transport. We also build a regime map based on the existence of an open view channel and provide concrete design guidelines for thermal conductivity modulation considering the kink angle and arm length. This study opens up new opportunities for efficient heat flow manipulation through nanostructure patterning.

Effects of structural changes on antibacterial activity and cytotoxicity due to proline substitutions in chimeric peptide HnMc.

Owing to the rapidly increasing emergence of multidrug-resistant pathogens, antimicrobial peptides (AMPs) are being explored as next-generation antibiotics. However, AMPs present in nature are highly toxic and exhibit low antibacterial activity. Simple modifications, such as amino acid substitution, can enhance antimicrobial activity and cell selectivity. Herein, we show that HnMc-W, substituted by the Phe1Trp analog of HnMc, a chimeric peptide, resulted in membranolytic antibacterial action and enhanced salt tolerance, whereas HnMc-WP1 with one Ser9Pro substitution resulted in a proline-kink helical structure that increased salt-tolerant antibacterial effects and reduced cytotoxicity. In addition, the HnMc-WP2 peptide, designed with a PXXP motif, had a flexible central hinge in its α-helical structure due to the introduction of two Pro and two Gln (X positions, by deletion of two Gln at positions 16 and 17) residues instead of Ser at position. HnMc-WP2 exhibited excellent antibacterial effects without cytotoxicity in vitro. Moreover, its potent antibacterial activity was demonstrated in a drug-resistant Pseudomonas aeruginosa-infected mouse model in vivo. Our findings provide valuable information for the design of peptides with high antibacterial activity and cell selectivity.

Self-emitted surface corrugations in dynamic fracture of silicon single crystal.

When a dynamic crack front travels through material heterogeneities, elastic waves are emitted, which perturb the crack and change the morphology of the fracture surface. For asperity-free crystalline materials, crack propagation along preferential cleavage planes is expected to present a smooth crack front and form a mirror-like fracture surface. Surprisingly, we show here that in single crystalline silicon without material asperities, the crack front presents a local kink during high-speed crack propagation. Meanwhile, local oscillations of the crack front, which can move along the crack front, emerge at the front kink position and generate periodic fracture surface corrugations. They grow from angstrom amplitude to a few hundred nanometers and propagate with a long lifetime at a frequency-dependent speed, while keeping a scale-independent shape. In particular, the local front oscillations collide in a particle-like manner rather than proceeding with a linear superposition upon interaction, which presents the characteristic of solitary waves. We propose that such a propagating mode of the crack front, which results from the fracture energy fluctuation at a critical crack speed in the silicon crystal, can be considered as nonlinear elastic waves that we call "corrugation waves."

Estimation and inference for multikink expectile regression with longitudinal data.

In this article, we investigate parameter estimation, kink points testing and statistical inference for a longitudinal multikink expectile regression model. The estimators for the kink locations and regression coefficients are obtained by using a bootstrap restarting iterative algorithm to avoid local minima. A backward selection procedure based on a modified BIC is applied to estimate the number of kink points. We theoretically demonstrate the number selection consistency of kink points and the asymptotic normality of all estimators. In particular, the estimators of kink locations are shown to achieve root-n consistency. A weighted cumulative sum type statistic is proposed to test the existence of kink effects at a given expectile, and its limiting distributions are derived under both the null and the local alternative hypotheses. The traditional Wald-type and cluster bootstrap confidence intervals for kink locations are also constructed. Simulation studies show that the proposed estimators and test have desirable finite sample performance in both homoscedastic and heteroscedastic errors. Two applications to the Nation Growth, Lung and Health Study and Capital Bike sharing dataset in Washington D.C. are also presented. The R codes for simulation studies and the real data are available at https://github.com/wangleink/MKER.

The role of point defects related with carbon impurity on the kink of logJ-Vin GaN-on-Si epitaxial layers.

Carbon impurity as point defects makes key impact on the leakage in GaN-on-Si structures. GaN-based epitaxial layers with different point defects by changing carbon-doped concentration were used to investigate the point defects behavior. It was found that leakage mechanisms correspond with space-charge-limited current models at low voltages, and after 1st kink, electron injection from silicon to GaN and PF conduction play a key role in the leakage of both point defects case with low carbon and high carbon doped. In addition, high carbon in GaN-on-Si epitaxial layers obtained lower leakage and larger breakdown voltage. The slope of logJ-Vhas two kinks and effective energy barrierEahas two peaks, 0.4247 eV at about 300 V and 0.3485 eV at about 900 V, respectively, which is related to accepted states and donor states related with carbon impurity. While the slope of logJ-Vhas one kink and effective energy barrierEahas one peak, 0.4794 eV at about 400 V of low carbon in GaN-on-Si epitaxial layers, indicating only field-induced accepted ionized makes impact on leakage. The comparative results of more donor trap density in high carbon indicate point defects related with carbon impurity play a key role in the kinks of logJ-Vslope.

Findings From a Community Survey of Individuals Who Engage in Pup Play.

This study presents findings from a community survey on pup play. Pup play is a kink activity and a form of role play that is growing in popularity internationally, and gaining increasing attention in sexology, yet prior research on pup play has almost entirely employed qualitative methods and primarily involved gay and bisexual men. Using survey data of 733 pup play participants primarily from the US, but also internationally, this study reports on the demographics of participants, how they engage in pup play, its social and sexual elements, and how it relates to social identity and mental health. Unique pup names and identifying with breeds of dogs were used to foster a sense of individuality within pup play, while the majority of participants owned and wore gear when engaging in pup play. We also found significant associations between being younger and identifying as a pup. Most participants reported that pup play improved their mental health. Binary logistic regression analyses indicated that having a mental health diagnosis was associated with identifying with a more social style of pup play and self-reporting the mental health benefits of pup play. We find that the conceptualization of pup play in the existing literature to be accurate to this international sample and highlight areas where further research is needed, alongside limitations of the study.

"It Was Scary, But Then It Was Kind of Exciting": Young Women's Experiences with Choking During Sex.

Choking/strangulation during sex is prevalent among young adults, with one study finding that 58% of women college students had ever been choked during sex. However, no qualitative study has examined women's experiences with choking/strangulation during sex outside of intimate partner violence. The purpose of our qualitative interview study was to investigate women's experiences with choking and/or being choked during partnered sex. Through in-depth interviews with 24 undergraduate and graduate women students ages 18 to 33, we sought to understand how women communicate about choking, their learning about and initiation into choking, their feelings about being choked and choking others, as well as consent and safety practices used in relation to choking. We found that women had first learned about choking through diverse sources including pornography, erotic stories, magazines, social media, friends, and partners. While all 24 women had been choked during sex, only 13 of 24 had ever choked a partner. They described having engaged in choking with men as well as women and with committed as well as more casual partner types. Participants described consensual and non-consensual choking experiences. While many women enjoyed choking, others did it largely to please their sexual partner. Women described different methods and intensities of having been choked. Although very few had ever sought out information on safety practices or risk reduction, and only some had established safe words or safe gestures with partners, participants consistently expressed a belief that the ways in which they and their partner(s) engaged in choking were safe.

BDSM, Non-Monogamy, Consent, and Stigma Navigation: Narrative Experiences.

With the rise in popularity of media pieces depicting alternative sexual/relationship preferences, there has been a rise in interest in kink and BDSM (Sprott & Berkey, 2015), which corresponds with research suggesting that approximately 20% of Americans have been in a consensually non-monogamous relationship (Haupert et al., 2016). Despite this growing popularity, these populations are often stigmatized and misunderstood (Bettinger, 2002). The present study examined the self-reported experiences of individuals who have participated in kink, BDSM, non-monogamy, and/or polyamory. Specifically, the study used qualitative methodology to examine narratives of discrimination, harassment, coming out, being outed, consent violations, and/or sexual assault in a BDSM or non-monogamous encounter. Participants consisted of 67 adults who completed an online survey conducted by the National Coalition for Sexual Freedom and were asked to provide narratives of their experience. Data were analyzed using a modified consensual qualitative research methodology (CQR-M; Spangler et al., 2012). Results indicated 11 categories falling into three domains: navigating incidents (consent issues, negotiation of scenes or relationships, identity/beliefs about coming out, and reporting), contributing factors (role of social media/media, exacerbating factors, and beliefs about the community), and response/prevention (outcome of incident, emotions felt, lessons learned from incident by the participant, and what would be helpful from the community). This study contributes to our understanding of the experiences in this community and elucidates strategies that can be used to intervene and advocate for these populations, including education of the general public and deliberate community support.

Kink-band formation in the directionally-solidified Mg/LPSO two-phase alloys.

The variation in the mechanical properties with the volume fraction of the long-period stacking ordered (LPSO) phase in directionally solidified (DS) Mg/LPSO two-phase alloys was examined. Unexpectedly, the yield stress of the DS alloys increases non-monotonically with an increase in the volume fraction of the LPSO phase. The LPSO phase is considered an effective strengthening phase in Mg alloys, when the stress is applied parallel to the growth direction. Nevertheless, the highest strength was obtained in alloys with 61-86 vol.% of the LPSO phase, which was considerably higher than that in the LPSO single-phase alloy. It was clarified that this complicated variation in the yield stress was generated from the change in the formation stress of kink bands, which varied with the thickness of the LPSO-phase grains. Furthermore, the coexistence of Mg in the LPSO phase alloy induced the homogeneous formation of kink bands in the alloys, leading to the enhancement of the 'kink-band strengthening'. The results demonstrated that microstructural control is significantly important in Mg/LPSO two-phase alloys, in which both phases exhibit strong plastic anisotropy, to realize the maximum mechanical properties.

Sub-Band Spectrum Engineering via Structural Order in Tapered Nanowires.

The cross-sectional dimensions of nanowires set the quantization conditions for the electronic subbands they host. These can be used as a platform to realize one-dimesional topological superconductivity. Here we develop a protocol that forces such nanowires to kink and change their growth direction. Consequently, a thin rectangular nanoplate is formed, which gradually converges into a very thin square tip. We characterize the resulting tapered nanowires structurally and spectroscopically by scanning and transmission electron microscopy and scanning tunneling microscopy and spectroscopy and model their growth. A unique structure composed of ordered rows of atoms on the (110) facet of the nanoflag is further revealed by atomically resolved topography and modeled by simulations. We discuss possible advantages tapered InAs nanowires offer for Majorana zero-mode realization and manipulation.

Formation of Plasmonic Polarons in Highly Electron-Doped Anatase TiO2.

The existence of various quasiparticles of polarons because of electron-boson couplings plays important roles in determining electron transport in titanium dioxide (TiO2), which affects a wealth of physical properties from catalysis to interfacial superconductivity. In addition to the well-defined Fröhlich polarons whose electrons are dressed by the phonon clouds, it has been theoretically predicted that electrons can also couple to their own plasmonic oscillations, namely, the plasmonic polarons. Here we experimentally demonstrate the formation of plasmonic polarons in highly doped anatase TiO2 using angle-resolved photoemission spectroscopy. Our results show that the energy separation of plasmon-loss satellites follows a dependence on √n, where n is the electron density, manifesting the characteristic of plasmonic polarons. The spectral functions enable to quantitatively evaluate the strengths of electron-plasmon and electron-phonon couplings, respectively, providing an effective approach for characterizing the interplays among different bosonic modes in the complicate many-body interactions.

Can relief measures nudge compliance in a public health crisis? Evidence from a kinked fiscal policy rule.

We show that compensation measures aimed at improving the fairness of a crisis policy response can unintendedly nudge compliance with emergency rules. We combine information on the distribution of relief funds across Italian municipalities during the novel coronavirus pandemic with data tracking citizens' movements through mobile devices and navigation systems. To assess the impact of transfers on compliance, we exploit a sharp kink schedule in the allocation of funds. The empirical analysis provides evidence that compliance increased with transfers, suggesting that the observance of emergency rules also depends on the fairness of the pandemic policy response.

Kink in an English Field: The Drinking, Drug use and Sexual Practices of English Festival-Goers Who Engage in Kink.

Little is known about the other leisure activities of people who engage in kink, including sexual practices and the use of alcohol and other drugs. This article examines the drinking, illicit drug use and sexual practices of people who engage in kink from a novel sample of attendees at an English festival. Of 966 respondents, 64 reported having engaged in kink within the past 12 months. We provide evidence of these respondents' self-reported demographic characteristics, alcohol and other drug use in their lifetime and within the past 12 months, as well as other sexual practices they engaged in. This study illustrates the value of accessing participants through in situ festival fieldwork to understand kink practices, and helps us move beyond notions of clustered risky activities toward a leisure studies approach to understanding the practices of people who engage in kink.

The role of RNA structure in translational regulation by L7Ae protein in archaea.

A recent study has shown that archaeal L7Ae binds to a putative k-turn structure in the 5'-leader of the mRNA of its structural gene to regulate translation. To function as a regulator, the RNA should be unstructured in the absence of protein, but it should adopt a k-turn-containing stem-loop on binding L7Ae. Sequence analysis of UTR sequences indicates that their k-turn elements will be unable to fold in the absence of L7Ae, and we have demonstrated this experimentally in solution using FRET for the Archaeoglobus fulgidus sequence. We have solved the X-ray crystal structure of the complex of the A. fulgidus RNA bound to its cognate L7Ae protein. The RNA adopts a standard k-turn conformation that is specifically recognized by the L7Ae protein, so stabilizing the stem-loop. In-line probing of the natural-sequence UTR shows that the RNA is unstructured in the absence of L7Ae binding, but folds on binding the protein such that the ribosome binding site is occluded. Thus, L7Ae regulates its own translation by switching the conformation of the RNA to alter accessibility.