bluuebunny/crossref_metadata_2025 huggingface dataset:
Rebranding James Baldwin and His Queer Others
Authors: Zaborowska Magdalena J. , Radel Nicholas F. , Hatton Nigel , Gibson Ernest L.
Published: September 2020

“Rebranding James Baldwin and His Queer Others” was a session held
at the annual meeting of the American Studies Association in November 2019 in
Honolulu, Hawaii. The papers gathered here show how Baldwin’s writings
and life story participate in dialogues with other authors and artists who probe
issues of identity and identification, as well as with other types of texts and
non-American stories, boldly addressing theoretical and political perspectives
different from his own. Nick Radel’s temporal challenge to reading novels
on homoerotic male desire asks of us a leap of faith, one that makes it possible
to read race as not necessarily a synonym for “Black,” but as a
powerful historical and sexual trope that resists “over-easy”
binaries of Western masculinity. Ernest L. Gibson’s engagement with
Beauford Delaney’s brilliant art and the ways in which it enabled the
teenage Baldwin’s “dark rapture” of self-discovery as a
writer reminds us that “something [has been missing] in our discussions
of male relationships.” Finally, Nigel Hatton suggests “a
relationship among Baldwin, Denmark, and Giovanni’s Room
that adds another thread to the important scholarship on his groundbreaking work
of fiction that has impacted African-American literature, Cold War studies,
transnational American studies, feminist thought, and queer theory.” All
three essays enlarge our assessment of Baldwin’s contribution to
understanding the ways gender and sexuality always inflect racialized Western
masculinities. Thus, they help us work to better gauge the extent of
Baldwin’s influence right here and right now.
Birthing a New World
Authors: Smith Marquita R.
Published: September 2020

This essay analyzes how James Baldwin’s late novel If Beale Street
Could Talk represents Black women’s care work in the face of
social death as an example of how Black women act as surrogates for Black
liberation giving birth to a new world and possibilities of freedom for Black
(male) people. Within the politics of Black nationalism, Black women were
affective workers playing a vital role in the (re)creation of heteronormative
family structures that formed the basis of Black liberation cohered by a belief
in the power of patriarchy to make way for communal freedom. This essay
demonstrates how Beale Street’s imagining of freedom
centers not on what Black women do to support themselves or each other, but on
the needs of the community at large, with embodied sacrifice as a presumed
condition of such liberation.
Stoichiometric interactions explain spindle dynamics and scaling across 100 million years of nematode evolution
Authors: Farhadifar Reza , Yu Che-Hang , Fabig Gunar , Wu Hai-Yin , Stein David B , Rockman Matthew , Müller-Reichert Thomas , Shelley Michael J , Needleman Daniel J
Published: September 2020

The spindle shows remarkable diversity, and changes in an integrated fashion, as cells vary over evolution. Here, we provide a mechanistic explanation for variations in the first mitotic spindle in nematodes. We used a combination of quantitative genetics and biophysics to rule out broad classes of models of the regulation of spindle length and dynamics, and to establish the importance of a balance of cortical pulling forces acting in different directions. These experiments led us to construct a model of cortical pulling forces in which the stoichiometric interactions of microtubules and force generators (each force generator can bind only one microtubule), is key to explaining the dynamics of spindle positioning and elongation, and spindle final length and scaling with cell size. This model accounts for variations in all the spindle traits we studied here, both within species and across nematode species spanning over 100 million years of evolution.
Bimodal function of chromatin remodeler Hmga1 in neural crest induction and Wnt-dependent emigration
Authors: Gandhi Shashank , Hutchins Erica J , Maruszko Krystyna , Park Jong H , Thomson Matthew , Bronner Marianne E
Published: September 2020

During gastrulation, neural crest cells are specified at the neural plate border, as characterized byPax7expression. Using single-cell RNA sequencing coupled with high-resolutionin situhybridization to identify novel transcriptional regulators, we show that chromatin remodelerHmga1is highly expressed prior to specification and maintained in migrating chick neural crest cells. Temporally controlled CRISPR-Cas9-mediated knockouts uncovered two distinct functions ofHmga1in neural crest development. At the neural plate border,Hmga1regulates Pax7-dependent neural crest lineage specification. At premigratory stages, a second role manifests whereHmga1loss reduces cranial crest emigration from the dorsal neural tube independent ofPax7.Interestingly, this is rescued by stabilized ß-catenin, thus implicatingHmga1as a canonical Wnt activator. Together, our results show thatHmga1functions in a bimodal manner during neural crest development to regulate specification at the neural plate border, and subsequent emigration from the neural tube via canonical Wnt signaling.
Unbiased homeologous recombination during pneumococcal transformation allows for multiple chromosomal integration events
Authors: Kurushima Jun , Campo Nathalie , van Raaphorst Renske , Cerckel Guillaume , Polard Patrice , Veening Jan-Willem
Published: September 2020

The spread of antimicrobial resistance and vaccine escape in the human pathogenStreptococcus pneumoniaecan be largely attributed to competence-induced transformation. Here, we studied this process at the single-cell level. We show that within isogenic populations, all cells become naturally competent and bind exogenous DNA. We find that transformation is highly efficient and that the chromosomal location of the integration site or whether the transformed gene is encoded on the leading or lagging strand has limited influence on recombination efficiency. Indeed, we have observed multiple recombination events in single recipients in real-time. However, because of saturation and because a single-stranded donor DNA replaces the original allele, transformation efficiency has an upper threshold of approximately 50% of the population. The fixed mechanism of transformation results in a fail-safe strategy for the population as half of the population generally keeps an intact copy of the original genome.
Light-regulated allosteric switch enables temporal and subcellular control of enzyme activity
Authors: Shaaya Mark , Fauser Jordan , Zhurikhina Anastasia , Conage-Pough Jason E , Huyot Vincent , Brennan Martin , Flower Cameron T , Matsche Jacob , Khan Shahzeb , Natarajan Viswanathan , Rehman Jalees , Kota Pradeep , White Forest M , Tsygankov Denis , Karginov Andrei V
Published: September 2020

Engineered allosteric regulation of protein activity provides significant advantages for the development of robust and broadly applicable tools. However, the application of allosteric switches in optogenetics has been scarce and suffers from critical limitations. Here, we report an optogenetic approach that utilizes an engineered Light-Regulated (LightR) allosteric switch module to achieve tight spatiotemporal control of enzymatic activity. Using the tyrosine kinase Src as a model, we demonstrate efficient regulation of the kinase and identify temporally distinct signaling responses ranging from seconds to minutes. LightR-Src off-kinetics can be tuned by modulating the LightR photoconversion cycle. A fast cycling variant enables the stimulation of transient pulses and local regulation of activity in a selected region of a cell. The design of the LightR module ensures broad applicability of the tool, as we demonstrate by achieving light-mediated regulation of Abl and bRaf kinases as well as Cre recombinase.
Forced Marriage Real Simple
Authors: Baumeister Hannah
Published: September 2020

The concepts of 'real rape' and 'real rape victim' play a key role in the reporting and prosecution of rape cases and strongly influence their outcomes. Similar biases and misconceptions obscure other acts of gender-based violence such as forced marriage in times of armed conflict.
This paper analyses how the Special Court for Sierra Leone, the Extraordinary Chambers in the Courts of Cambodia and the International Criminal Court construct and reconstruct the concepts of a 'real' and 'simple forced marriage'. It argues that the difference lies in the elements of consent,
coercion, duration and purpose. The paper highlights the gendered everyday realities in which myths surrounding conflict-related forced marriage are embedded and then taken for granted and accepted as normal, contributing to the denial, downplay or justification of acts of violence against
women. It argues that by reinforcing these concepts, courts miss an opportunity to educate the legal community and the public about women's experiences in peace and wartime and to develop a definition of the crime of forced marriage that reflects women's realities.
Measurements of the gingival papillae architecture using cone-beam computed tomography in young Chinese adults
Authors: Yang Gang , Cao Jie , Hu Wenjie , Chung Kwok-Hung
Published: September 2020

Background

The aim of this study was to measure the morphology of interdental papillae (IP) in maxillary anterior teeth using cone-beam computed tomography (CBCT).

Methods

Twenty-seven periodontally healthy subjects with 135 IP were evaluated by means of periodontal examination and a CBCT scan with an elastomeric matrix containing radiopaque material in position. According to the status of tooth contact and presence of IP, subjects were categorized into three groups: open contact point, complete papillae, and deficient papillae group. The papillae height (PH), facial-lingual thickness (FLT), and interdental distance (IDD) were measured. Data was analyzed with the significance level atα = 0.05.

Results

The mean PH values were 4.17 ± 0.51 mm, 3.99 ± 0.61 mm, and 3.99 ± 0.62 mm, for the open contact group, complete papilla, and deficient papilla group, respectively. The PH values of the recorded sites among central incisors, lateral incisors, and canine were 4.13 ± 0.56 mm, 3.87 ± 0. 63 mm, and 4.07 ± 0.58 mm, respectively. No statistically significant differences of the PH values were determined between the above three tested groups as well as between the different sites (p > 0.05). The IDD values obtained from the complete papilla group were significantly lower than the other tested groups (p < 0.05).

Conclusion

The contact point condition of upper anterior sextants may not influence the presence and dimension of the IP in periodontally healthy subjects.
The health-related quality of life of Syrian refugee women in their reproductive age
Authors: Nabolsi Manar , Safadi Reema , Sun Carolyn , Ahmad Muayyad , Al-Maharma Du’a , Halasa Suhaila , Saleh Mohammad , Dohrn Jennifer
Published: September 2020

Background

Health-Related Quality of Life (HRQoL) for refugee women in reproductive age is highly affected by physical, political, psychosocial and environmental conditions in countries of asylum. HRQoL is enormously affected by the satisfaction of this vulnerable group with the physical, psychological, emotional and social care services provided in this critical time. Therefore, this study aimed toassess the HRQoL among Syrian refugee women of reproductive age living outside camps in Jordan.

Methods

A cross-sectional correlational study was conducted with a convenience sample of 523 Syrian refugee women in the host communities in Jordan.Health-related quality of life (HRQOL) was measured using the short-form 36 (SF-36) questionnaire.

Results

Significant negative correlations were found between SF-36 individual subscales score and the length of marriage, the number of children, parity and family income. The strongest correlations were between pain scale and length of marriage (r =  − .21), and between Energy/Fatigue and ‘number of children’ (r =  − .21). Conversely, antenatal care was positively correlated with physical, role emotional, pain, and general health. Physical functioning and general health were predicted significantly with less years of marriage, younger age at marriage, less violence and by higher family income.

Conclusion

This study suggests low HRQoL scores for women of reproductive age across all domains. Several factors such as years of marriage, age at marriage, the number of children, violence, antenatal care and family income affected the women’s general health. The provision of appropriate and accessible reproductive and maternal healthcare services in antenatal visits is critical for ensuring the immediate and long-term health and wellbeing of refugee women and their families.
Production of Biscuits from Mixture of Tiger Nut Flour, Milk Permeate and Soft Wheat Flour
Authors: Shenawy Moustafa El- , Hussien Ahmed M. S. , Fouad Mohamed Tawfeek
Published: September 2020

This study was carried out to use mixture of permeate and germinated tiger nut flour(GTNF), soft wheat flour(SWF) for production and evaluation of biscuit product. Biscuits made of 100% SWF and permeate was also prepared for comparison. Chemical composition, mixolab parameters, color attributes, baking quality, and sensory properties of biscuits were studied. GTNF was added to SWF at 10,20 and 30% level. Results revealed that GTNF characterized with its higher fiber (5.41%), fat (27.85%) and ash (3.24%).Therefore, increasing mixing level of GTNF with SWF led to increase the nutritional value of biscuits. Mixolab parameters showed that water absorption and dough stability was increased as the percentage of GTNF in SWF increase. Baking quality of biscuits showed that all biscuit samples from mixing GTNF with SWF had lower volume and specific volume than control. Results also showed that Hunter color parameters (L*, a* & b*) of biscuits were darker as mixing level of GTNF increased. This result was confirmed with the obtained sensorial results. Also, the bacteriological parameters were within the permissible bacterial limits, adopted by the Egyptian Standers, until 3-6 months of storage. Moreover, sensory evaluation of biscuits indicated that all treatments were acceptable, moreover mixture contained GTNF had superior nutritional value and could be suitable for child nutrition.
Chemical and Antioxidant Quality of Breakfast Cereal Extruded from Maize Grits, Partially Defatted Peanut and Beetroot Flour Blend
Authors: Akor I. A. , Ukeyima T. M. , Kyenge B. , Ochele P.
Published: September 2020

The mineral, essential and non essential amino acids contents and the antioxidant capacity of extruded breakfast cereal from maize grits, partially defatted peanut and beetroot flour blends was investigated. Composite flour blends were prepared from maize, peanuts and beetroot flour in the following proportion A= (100% Maize flour as control), B= (90:0:10), C= (90:10:0), D= (80:10:10), E= (70:20:10), F= (60:30:10), and G= (50:40:10). There was significant difference in the mineral composition of composite flour blends, the values ranged from 6.05-62.32 mg/g, 0.83-4.53 mg/g, 1.03-3.14 mg/g, 163.81-640.03 mg/g for calcium, iron, zinc, potassium respectively. The esstenial amino acids values of the four blends for isoleucine, leucine, lysine, methionine, alanine, threonine, tryptohan and valine ranged from 0.24-1.25, 0.04-1.08, 0.08-0.40, 0.13-0.49, 0.28-0.48, 0.22-0.44, 0.4-0.24 and 0.30-0.69 respectively. There was increase in antioxidant capacity of the sample with beetroot and peanut inclusion. The 2.2 diphenyl 1-1 picryl hydroxyl (DPPH) radical scavenging activity ranged from 4.03-16.83 while the ferric reducing antioxidant power ranged from 15.65-45.53 MgGAE/Mol with trolox equivalent antioxidant capacity was from 10.21-37.01 mmol trolox/Mol and the total phenohic sontent 5.01-22.01 MgGAE/g.
Standardization of Nagaraja Guliya; A Sri Lankan Traditional Formula Used in Poisons of Animal Origin (Jangama Visha)
Authors: Eshwara J. H. K. , Kulathunga R. D. H. , Gunarathna E. D. T. P.
Published: September 2020

Sri Lanka has unique heritage of own medical system handed down from generation to another over a period of 3,000 years.  Native medical practitioners in different disciplines are inherited within a family tradition and their treatments are still effective and accepted by the Sri Lankan community.  Nagaraja Guliya is one of traditional preparations prescribed as internal or external medicaments by the traditional physicians in the southern province in Sri Lanka since ten decades for poisons of animal origin. The study has been focused to standardize the herbo mineral formula in respect of quality, safety and analyze the potential of Nagaraja Guliya. The formulation consists of the eight herbo mineral ingredients; Aconitum ferox, Zingiber officinale, Myristica fragrans, Syzygium aromaticum, Mercury, Arsenic trisulfide, Copper sulphate and Luffa cylindrica. Authentication of the ingredients was carried out at Bandaranayaka Memorial Ayurveda Research Institute, Nawinna, Sri Lanka. Data has been gathered from Sri Lankan traditional manuscripts, Ayurveda authentic texts and different scientific journals. The results revealed that the Nagaraja Guliya contains secondary plant metabolites like Alkaloids, Tannins, Saponin and Phenols. The pH of the formulation was found to be 5.28 and is in acceptable range for oral administration and external application. Further, heavy metal contents of Mercury and Arsenic in the preparation was not reached to the harmful level to the human body. In Ayurveda view point; pharmacodynamic properties of the formula showed that maximum number of ingredients consist of Katu Rasa (pungent taste) Laghu Guna (Light property), Ushna Veerya (Hot in potency) and Katu vipaka with properties of pacification of Kapha and Vata dosha. Kushtagna, Vedanastapana, Raktashodaka, Shotahara and Vishahara. Hence, future studies should be planned to evaluate the existing data on traditional use of Nagaraja Guliya, along with experimental and clinical trials.
Some Statistical Properties of a Weighted Distribution and Its Application to Waiting Time Data
Authors: Singh Brijesh P. , Das Utpal Dhar
Published: September 2020

The weighted distribution is mainly used in various real life fields such as ecology, reliability engineering, medical science etc. Some statistical properties are derived such as moment generating function, characteristic function, cumulative generating function, the hazard function, Renyi entropy, Cumulative residual entropy. For parameter estimation maximum likelihood estimation method is used. The considered weighted probability distribution is applied to two real data sets of waiting time to examine the suitability and applicability.
Leg Length Discrepancies in Nigerian Children with Sickle Cell Anaemia
Authors: Ihuarula Eneh Chizoma
Published: September 2020

Background: Sickle cell anaemia, (SCA) the homozygous and most severe of the sickle cell diseases exerts adverse effects on growth and linear body proportions. In Nigeria, these changes in the lower extremity are scarcely documented.

Objectives: To evaluate the differences between the real leg lengths and apparent leg lengths determined by tape measure among children with SCA.

Methods: A clinic-based, cross-sectional, comparative study of 140 age and sex matched “SS” and “AA” children. The real leg lengths, anterior superior iliac spine to medial malleolus and to the heel, the apparent leg length, umbilicus to the medial malleolus were measured with a plastic tape and recorded. 

Leg length discrepancy (LLD), the arithmetric differences between corresponding leg lengths were recorded and classified into nil (0), mild (<2cm), moderate (2-5cm) and severe (>5cm).

Results: At the medial malleolus, the subjects had more mild and moderate Real LLD than controls while more controls than subjects had nil Real LLD (p = .033). Both right and left real leg lengths were significantly shorter in the 6-9 year old subjects especially the males, all female subjects, all 10-13 year olds subjects more so the females than their respective counterparts. (All p values < 0.05) Similarly, the right and left leg lengths at the heel were significantly shorter in subjects of the same age and sex groups as above than all their respective counterparts. (P values < 0.05). However, male subjects had only the right real leg length significantly shorter than those of the controls. Real LLD: ASIS-MM was significantly higher in 10-13 year old female subjects, real LLD: ASIS-HEEL in 14-18 year old subjects than the controls. The right and left apparent leg length were significantly lower in all 10-13 year old subjects as well as 10-13 year old female subjects than the respective matches. All p values were < 0.05. No significant difference existed in the apparent LLD comparisons.
Adipose‐derived mesenchymal stem cells differentiate into pancreatic cancer‐associated fibroblasts in vitro
Authors: Miyazaki Yoshihiro , Oda Tatsuya , Mori Nobuhito , Kida Yasuyuki S.
Published: September 2020

Cancer‐associated fibroblasts (CAFs) are key components of the dense, proliferating stroma observed in pancreatic ductal adenocarcinoma (PDAC), and CAF subpopulations drive tumor heterogeneity and play a major role in PDAC progression and drug resistance. CAFs consist of heterogenous subpopulations such as myoblastic CAF (myCAF) and inflammatory CAF (iCAF), and each has distinct essential roles. However, it is not clear how CAF subpopulations are formed in PDAC. Adipose‐derived MSCs (AD‐MSCs), which possess a high multilineage potential and self‐renewal capacity, are reported to be one of the in vivo CAF sources. Here, we aimed to investigate whether AD‐MSCs can act as precursors for CAFs in vitro. We recorded morphological features and collected omics data from two in vitro co‐culture models for recapitulating clinical PDAC. Additionally, we tested the advantages of the co‐culture model in terms of accurately modeling morphology and CAF heterogeneity. We showed that AD‐MSCs differentiate into two distinct CAF subpopulations: Direct contact co‐culture with PDAC cell line Capan‐1 induced differentiation into myCAFs and iCAFs, while indirect co‐culture induced differentiation into only iCAFs. Using these co‐culture systems, we also identified novel CAF markers that may be helpful for elucidating the mechanisms of CAFs in the tumor microenvironment (TME). In conclusion, AD‐MSCs can differentiate into distinct CAF subtypes depending on the different co‐culture conditions in vitro, and the identification of potential CAF markers may aid in future investigations of the mechanisms underlying the role of CAFs in the TME.
Sunlight Exposure, Sun‐Protective Behavior, and Anti–Citrullinated Protein Antibody Positivity: A General Population‐Based Study in Quebec, Canada
Authors: Zhao Naizhuo , Smargiassi Audrey , Colmegna Ines , Hudson Marie , Fritzler Marvin , Bernatsky Sasha
Published: September 2020

Objective

To examine associations between sunlight exposure and anti–citrullinated protein antibodies (ACPAs) using general population data in Quebec, Canada.

Methods

A random sample of 7,600 individuals (including 786 subjects who were ACPA positive and 201 self‐reported rheumatoid arthritis [RA] cases) from the CARTaGENE cohort was studied cross‐sectionally. All subjects were nested in 4 census metropolitan areas, and mixed‐effects logistic regression models were used to calculate odds ratios (ORs) and 95% confidence intervals (95% CIs) for ACPA positivity related to sunlight exposure, adjusting for sun‐block use, industrial fine particulate matter (PM2.5) exposures, smoking, age, sex, French Canadian ancestry, and family income. We also performed sensitivity analyses excluding subjects with RA, defining ACPA positivity by higher titers, and stratifying by age and sex.

Results

The adjusted ORs and 95% CIs did not suggest conclusive associations between ACPA and sunlight exposure or sun‐block use, but robust positive relationships were observed between industrial PM2.5 emissions and ACPA (OR 1.19 per μg/m3 [95% CI 1.03–1.36] in primary analyses).

Conclusion

We did not see clear links between ACPA and sunlight exposure or sun‐block use, but we did note positive associations with industrial PM2.5. Future studies of sunlight and RA (or ACPA) should take air pollution exposures into account.
Hollow Microfibers of Elastomeric Nanocomposites for Fully Stretchable and Highly Sensitive Microfluidic Immunobiosensor Patch
Authors: Huynh Van Long , Trung Tran Quang , Meeseepong Montri , Lee Han‐Byeol , Nguyen Trong Danh , Lee Nae‐Eung
Published: September 2020

The on‐body immunodetection of biomarkers in sweat would significantly augment the potential of wearable body‐interfaced biosensors for self‐testing but has been limited due to the difficulty of integrating liquid handling and immunobiosensing devices in a wearable platform. Herein, a stretchable microfluidic immunobiosensor (SMIB) patch with hollow microfibers of elastomeric nanocomposites for the highly sensitive on‐body biosensing of neuropeptide Y (NPY), a stress biomarker, in human sweat is reported. The SMIB patch is composed of a stretchable liquid handling device and an electrochemical impedimetric immunobiosensor made of hollow and conductive microfibers of reduced graphene oxide (rGO) and rGO‐Ag nanowires in polyurethane matrix, respectively. The patch possesses a low limit of detection of 50 fm, a large dynamic range (50 fm–1 nm), good linearity, no labeling or reagent requirements, and facile formation in a patch form factor. By combining handling of the biofluid and delivery of the washing solution by a simple finger‐touch operation as well as the analytical capability of NPY with an extremely low concentration in human sweat, the SMIB patch is a promising approach toward wearable non‐invasive immunodetection for self‐testing.
High‐Precision 3D Bio‐Dot Printing to Improve Paracrine Interaction between Multiple Types of Cell Spheroids
Authors: Jeon Seunggyu , Heo Jun‐Ho , Kim Min Kyeong , Jeong Wonwoo , Kang Hyun‐Wook
Published: September 2020

Cell–cell interaction accounts for one of the most influential factors affecting the viability and functionality of cell‐based tissue models. In this respect, various methods capable of producing micro‐patterns with cell spheroids are introduced to simultaneously improve contact‐dependent and ‐independent cell‐cell interactions. However, no method has yet been designed to effectively generate precise 3D patterns with multiple spheroid types. In this study, a new high‐precision and convenient 3D spheroid printing technology is developed, designated as 3D bio‐dot printing. This new technique is designed to produce cell‐laden, non‐adhesive micro‐pores within 3D structures to allow cell spheroids to be induced at printed sites. Experimental results show that various cell types, including hepatocytes, pancreatic β‐cells, and breast cancer cells, can be employed for the in situ formation of cell spheroids, and 3D freeform structures with multiple spheroid types can be printed. Moreover, this novel technology can also be used for performing 3D invasion assays. More importantly, it ensures that the precise control of spheroid size and position is achieved at micrometer scale. Finally, the usefulness of this novel technology is demonstrated by producing multicellular micro‐patterns with primary hepatocyte spheroids and endothelial cells, that exhibit significantly improved long‐term hepatic function and drug metabolism.
Hysteresis, Loss and Nonlinearity in Epitaxial PbZr0.55Ti0.45O3 Films: A Polarization Rotation Model
Authors: Lucke Philip , Bayraktar Muharrem , Birkhölzer Yorick A. , Nematollahi Mohammadreza , Yakshin Andrey , Rijnders Guus , Bijkerk Fred , Houwman Evert P.
Published: September 2020

The phenomena of hysteresis, ferroelectric loss, and nonlinearity are investigated for the strain and polarization of a monoclinic, epitaxial Pb(Zr,Ti)O3 film over the 70 Hz to 5 kHz frequency range at sub‐coercive excitation fields and zero electrical bias. For the strain, a linear hysteretic behavior is found, whereas the polarization shows a strongly nonlinear hysteretic behavior. In contrast to polycrystalline structures (for instance in ceramics or chemical solution deposited thin films), the commonly referred Rayleigh model cannot explain the observed behavior. A new model is presented, based on the rotation of the polarization vector within the monoclinic or rhombohedral unit cell under an applied electric field, with the viscous interaction of domains accompanying the unit cell deformation. The model explains the amplitude and frequency scaling of the strain, polarization, and loss tangent as well as the observed higher harmonics of polarization in the measured epitaxial Pb(Zr,Ti)O3 films. It is concluded that the nonlinear response and the hysteretic loss originate from two separate physical processes. The nonlinear response is attributed to the nonlinear angular rotation of the polarization vector, whereas the hysteresis and ferroelectric loss are due to a viscous interaction of domains while the polarization vector is rotating.
Hierarchically Surface‐Textured Ultrastable Hybrid Film for Large‐Scale Triboelectric Nanogenerators
Authors: Lee Hyunhwan , Lee Han Eol , Wang Hee Seung , Kang Seung‐Mo , Lee Daewon , Kim Yun Hyeok , Shin Jung Ho , Lim Young‐Woo , Lee Keon Jae , Bae Byeong‐Soo
Published: September 2020

The supply of electrical power is indispensable in the internet of things (IoT) area. Triboelectric nanogenerators (TENGs) has been largely used as a power supply due to simple device structure and various possibilities of material selection. Although various surface modifications of TENG are utilized for improving the output performance of TENG, these methods have significant drawbacks of high‐cost fabrication process, limited device size, and wearing out. Here, a mechanically robust TENG using a newly developed surface‐textured glass fabric reinforced siloxane hybrid film (SGH film) is presented. The large‐scale SGH film is cost‐effectively fabricated via a simple roll‐to‐plate and UV curing process. The film is repeatedly duplicated over 100 times using one pre‐treated substrate mold. SGH film exhibits superior thermal and mechanical stability, compared to other polymer films. Finally, surface textured TENG (THTENG) is achieved using extremely stable SGH film, resulting in enhanced output power compared to flat TENG and high durability during the 100  000 cycles of TENG operation.
Chemically Stable Black Phase CsPbI3 Inorganic Perovskites for High‐Efficiency Photovoltaics
Authors: Wang Yong , Chen Yuetian , Zhang Taiyang , Wang Xingtao , Zhao Yixin
Published: September 2020

Research on chemically stable inorganic perovskites has achieved rapid progress in terms of high efficiency exceeding 19% and high thermal stabilities, making it one of the most promising candidates for thermodynamically stable and high‐efficiency perovskite solar cells. Among those inorganic perovskites, CsPbI3 with good chemical components stability possesses the suitable bandgap (≈1.7 eV) for single‐junction and tandem solar cells. Comparing to the anisotropic organic cations, the isotropic cesium cation without hydrogen bond and cation orientation renders CsPbI3 exhibit unique optoelectronic properties. However, the unideal tolerance factor of CsPbI3 induces the challenges of different crystal phase competition and room temperature phase stability. Herein, the latest important developments regarding understanding of the crystal structure and phase of CsPbI3 perovskite are presented. The development of various solution chemistry approaches for depositing high‐quality phase‐pure CsPbI3 perovskite is summarized. Furthermore, some important phase stabilization strategies for black phase CsPbI3 are discussed. The latest experimental and theoretical studies on the fundamental physical properties of photoactive phase CsPbI3 have deepened the understanding of inorganic perovskites. The future development and research directions toward achieving highly stable CsPbI3 materials will further advance inorganic perovskite for highly stable and efficient photovoltaics.
Rational Design of Semiconductor‐Based Chemiresistors and their Libraries for Next‐Generation Artificial Olfaction
Authors: Jeong Seong‐Yong , Kim Jun‐Sik , Lee Jong‐Heun
Published: September 2020

Artificial olfaction based on gas sensor arrays aims to substitute for, support, and surpass human olfaction. Like mammalian olfaction, a larger number of sensors and more signal processing are crucial for strengthening artificial olfaction. Due to rapid progress in computing capabilities and machine‐learning algorithms, on‐demand high‐performance artificial olfaction that can eclipse human olfaction becomes inevitable once diverse and versatile gas sensing materials are provided. Here, rational strategies to design a myriad of different semiconductor‐based chemiresistors and to grow gas sensing libraries enough to identify a wide range of odors and gases are reviewed, discussed, and suggested. Key approaches include the use of p‐type oxide semiconductors, multinary perovskite and spinel oxides, carbon‐based materials, metal chalcogenides, their heterostructures, as well as heterocomposites as distinctive sensing materials, the utilization of bilayer sensor design, the design of robust sensing materials, and the high‐throughput screening of sensing materials. In addition, the state‐of‐the‐art and key issues in the implementation of electronic noses are discussed. Finally, a perspective on chemiresistive sensing materials for next‐generation artificial olfaction is provided.
High Thermoelectric Performance in n‐Type Perylene Bisimide Induced by the Soret Effect
Authors: Jiang Qinglin , Sun Hengda , Zhao Duokai , Zhang Fengling , Hu Dehua , Jiao Fei , Qin Leiqiang , Linseis Vincent , Fabiano Simone , Crispin Xavier , Ma Yuguang , Cao Yong
Published: September 2020

Low‐cost, non‐toxic, abundant organic thermoelectric materials are currently under investigation for use as potential alternatives for the production of electricity from waste heat. While organic conductors reach electrical conductivities as high as their inorganic counterparts, they suffer from an overall low thermoelectric figure of merit (ZT) due to their small Seebeck coefficient. Moreover, the lack of efficient n‐type organic materials still represents a major challenge when trying to fabricate efficient organic thermoelectric modules. Here, a novel strategy is proposed both to increase the Seebeck coefficient and achieve the highest thermoelectric efficiency for n‐type organic thermoelectrics to date. An organic mixed ion–electron n‐type conductor based on highly crystalline and reduced perylene bisimide is developed. Quasi‐frozen ionic carriers yield a large ionic Seebeck coefficient of −3021 μV K−1, while the electronic carriers dominate the electrical conductivity which is as high as 0.18 S cm−1 at 60% relative humidity. The overall power factor is remarkably high (165 μW m−1 K−2), with a ZT = 0.23 at room temperature. The resulting single leg thermoelectric generators display a high quasi‐constant power output. This work paves the way for the design and development of efficient organic thermoelectrics by the rational control of the mobility of the electronic and ionic carriers.
Beyond Substrates: Strain Engineering of Ferroelectric Membranes
Authors: Pesquera David , Parsonnet Eric , Qualls Alexander , Xu Ruijuan , Gubser Andrew J. , Kim Jieun , Jiang Yizhe , Velarde Gabriel , Huang Yen‐Lin , Hwang Harold Y. , Ramesh Ramamoorthy , Martin Lane W.
Published: September 2020

Strain engineering in perovskite oxides provides for dramatic control over material structure, phase, and properties, but is restricted by the discrete strain states produced by available high‐quality substrates. Here, using the ferroelectric BaTiO3, production of precisely strain‐engineered, substrate‐released nanoscale membranes is demonstrated via an epitaxial lift‐off process that allows the high crystalline quality of films grown on substrates to be replicated. In turn, fine structural tuning is achieved using interlayer stress in symmetric trilayer oxide‐metal/ferroelectric/oxide‐metal structures fabricated from the released membranes. In devices integrated on silicon, the interlayer stress provides deterministic control of ordering temperature (from 75 to 425 °C) and releasing the substrate clamping is shown to dramatically impact ferroelectric switching and domain dynamics (including reducing coercive fields to <10 kV cm−1 and improving switching times to <5 ns for a 20 µm diameter capacitor in a 100‐nm‐thick film). In devices integrated on flexible polymers, enhanced room‐temperature dielectric permittivity with large mechanical tunability (a 90% change upon ±0.1% strain application) is demonstrated. This approach paves the way toward the fabrication of ultrafast CMOS‐compatible ferroelectric memories and ultrasensitive flexible nanosensor devices, and it may also be leveraged for the stabilization of novel phases and functionalities not achievable via direct epitaxial growth.
Filament‐Free Bulk Resistive Memory Enables Deterministic Analogue Switching
Authors: Li Yiyang , Fuller Elliot J. , Sugar Joshua D. , Yoo Sangmin , Ashby David S. , Bennett Christopher H. , Horton Robert D. , Bartsch Michael S. , Marinella Matthew J. , Lu Wei D. , Talin A. Alec
Published: September 2020

Digital computing is nearing its physical limits as computing needs and energy consumption rapidly increase. Analogue‐memory‐based neuromorphic computing can be orders of magnitude more energy efficient at data‐intensive tasks like deep neural networks, but has been limited by the inaccurate and unpredictable switching of analogue resistive memory. Filamentary resistive random access memory (RRAM) suffers from stochastic switching due to the random kinetic motion of discrete defects in the nanometer‐sized filament. In this work, this stochasticity is overcome by incorporating a solid electrolyte interlayer, in this case, yttria‐stabilized zirconia (YSZ), toward eliminating filaments. Filament‐free, bulk‐RRAM cells instead store analogue states using the bulk point defect concentration, yielding predictable switching because the statistical ensemble behavior of oxygen vacancy defects is deterministic even when individual defects are stochastic. Both experiments and modeling show bulk‐RRAM devices using TiO2‐X switching layers and YSZ electrolytes yield deterministic and linear analogue switching for efficient inference and training. Bulk‐RRAM solves many outstanding issues with memristor unpredictability that have inhibited commercialization, and can, therefore, enable unprecedented new applications for energy‐efficient neuromorphic computing. Beyond RRAM, this work shows how harnessing bulk point defects in ionic materials can be used to engineer deterministic nanoelectronic materials and devices.
Rare Earth‐Free Luminescent Materials for WLEDs: Recent Progress and Perspectives
Authors: Zhang Hui , Zhang Huqin , Pan Aizhao , Yang Biao , He Ling , Wu Youshen
Published: September 2020

The development and application of white light‐emitting diode (WLED) lighting technology are of great significance for reducing energy consumption. Commonly used WLED devices rely on the use of rare earth luminescent materials. However, rare earth elements are nonrenewable resources, and mining and refining processes have an adverse impact on the environment. In recent years, new white light‐emitting luminescent materials that do not contain rare earth elements have been developed, such as quantum dots, fluorescent carbon dots, perovskite luminescent materials, organic luminescent materials, and metal–organic framework materials, among others, some of which are successfully applied in the development of WLEDs. Herein the latest progress in this research field is reviewed, analyzing the construction of practical WLED devices and comparing the characteristics of newly developed rare earth‐free luminescent materials. Last, the future development prospects in this field are described.
Recent Advancements on Transition‐Metal‐Catalyzed, Chelation‐Induced ortho‐Hydroxylation of Arenes
Authors: Iqbal Zafar , Joshi Asha , Ranjan De Saroj
Published: September 2020

The phenols are key intermediates as well as desired products in many target oriented syntheses. The conversion of C−H bond to C−O bond is one of the most challenging tasks in organic synthesis. In last few decades, the hydroxylation of aromatic compounds has drawn a considerable attention because of their importance in Pharmaceutical industry, material chemistry, polymers and in agrochemicals. Indeed, transition‐metal‐catalyzed, coordination‐assisted regio‐ and chemoselective ortho‐hydroxylation of arenes has become very efficient and popular strategy to obtain good yields of phenols with tolerance of a wide range of functional groups. This review is the comprehensive summary of recent advancement on Pd‐, Ru‐, Rh‐, Cu‐ and Ir‐catalyzed, chelation‐controlled regioselective ortho‐C−H bond hydroxylation of aromatic compounds in the presence of diverse hydroxylating agents. The review has been classified on the sources of hydroxylating agents used in reaction.

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Modeling Optical Materials at the Single Scatterer Level: The Transition from Homogeneous to Heterogeneous Materials
Authors: Werdehausen Daniel , Santiago Xavier Garcia , Burger Sven , Staude Isabelle , Pertsch Thomas , Rockstuhl Carsten , Decker Manuel
Published: September 2020

Materials that contain distinct scatterers, for example, nanoparticles, with sizes exceeding 100 nm scatter light heavily and are heterogeneous. In contrast, the atomic or molecular scatterers in conventional optical materials form a homogeneous distribution on the scale of the wavelength. In this paper, the transition between homogeneous and heterogeneous materials is investigated. To this end, a procedure is introduced that allows for retrieving reliable refractive index values from full wave optical numerical simulations of the underlying multibody scattering problem. Using this procedure, it is shown that the concept of an effective refractive index breaks down on multiple levels as a material transitions out of the homogeneous regime. These findings allow for quantifying how novel dispersion‐engineered nanocomposites for bulk optical applications must be designed and show that Maxwell–Garnett‐type effective medium theories are accurate tools for the design of nanocomposites. The procedure can be readily generalized to other types of scatterers, including atoms and molecules and hence guide the design of different kinds of novel materials.
MeCas12a, a Highly Sensitive and Specific System for COVID‐19 Detection
Authors: Ma Peixiang , Meng Qingzhou , Sun Baoqing , Zhao Bing , Dang Lu , Zhong Mingtian , Liu Siyuan , Xu Hongtao , Mei Hong , Liu Jia , Chi Tian , Yang Guang , Liu Ming , Huang Xingxu , Wang Xinjie
Published: September 2020

Cas12a‐based systems, which detect specific nucleic acids via collateral cleavage of reporter DNA, display huge potentials for rapid diagnosis of infectious diseases. Here, the Manganese‐enhanced Cas12a (MeCas12a) system is described, where manganese is used to increase the detection sensitivity up to 13‐fold, enabling the detection of target RNAs as low as five copies. MeCas12a is also highly specific, and is able to distinguish between single nucleotide polymorphisms (SNPs) differing by a single nucleotide. MeCas12a can detect severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) in clinical samples and distinguish between SARS‐CoV‐2 and Middle East respiratory syndrome coronavirus (MERS‐CoV) RNA in simulated samples, thus offering an attractive alternative to other methods for the diagnosis of infectious diseases including COVID‐19 and MERS.
Ultra‐High Thermoelectric Performance in Bulk BiSbTe/Amorphous Boron Composites with Nano‐Defect Architectures
Authors: Yang Guangsai , Niu Ranming , Sang Lina , Liao Xiaozhou , Mitchell David R. G. , Ye Ning , Pei Jun , Li Jing‐Feng , Wang Xiaolin
Published: September 2020

Based on the Seebeck and Peltier effects, state‐of‐the‐art bismuth telluride‐based thermoelectric materials, which are capable of direct and reversible conversion of thermal to electrical energy, have great potential in energy harvesting and solid‐state refrigerators. However, their widespread use is limited by their low conversion efficiency, which is determined by the dimensionless figure‐of‐merit (ZT). Significant enhancement of ZT is a great challenge owing to the common interdependence of electrical and thermal conductivity. Here, it is demonstrated that by incorporating nanoamorphous boron into the p‐type Bi0.5Sb1.5Te3, a record high ZT of 1.6 at 375 K is achieved. It is shown that a high density of nanostructures and dislocations due to the incorporation of the boron inclusions, leads to a significant reduction of thermal conductivity and improved charge transport. The findings represent an important step to further promote the development of thermoelectric technology and its widespread application in solid‐state refrigeration and power generation from waste heat.
Coupling Effect of Piezo–Flexocatalytic Hydrogen Evolution with Hybrid 1T‐ and 2H‐Phase Few‐Layered MoSe2 Nanosheets
Authors: Chung Yun‐Jung , Yang Cheng‐Shiun , Lee Jyun‐Ting , Wu Guan Hua , Wu Jyh Ming
Published: September 2020

Hybrid 1T‐ and 2H‐phase MoSe2 nanosheets with active reaction sites, which display strong piezoelectric responses and extraordinary flexoelectric potential (flexopotential), are demonstrated. The strain‐induced piezoelectric potential (piezopotential) establishes at interfacial areas between 1T and 2H‐phase that modulates the local‐contact characteristics to enhance charge separation. The piezo‐ and flexopotential coupling effect is observed not only on edge‐site MoSe2 nanosheets but also on polarized surfaces of the MoSe2 nanosheets across the top and bottom surfaces, thus establishing an internal electric field to separate electron–hole pairs and proceeding with electrochemical reaction with polar molecules, generating hydrogen gas at ≈5000 µmol g−1 h−1. The nanosheets assemble nanoflowers with abundant edge‐sites, which serve as cantilever beams for traction force at the free ends of nanosheets. On increasing the bending moment, an extraordinary flexopotential results along the z‐axis. The strain gradients induce piezo–flexoelectric coupling effects on numerous edge‐site nanosheets, structural boundaries, and the polarized surface along the z‐axis, which potentially facilitate a state‐of‐the‐art catalytic hydrogen evolution reaction.
3D CoSe@C Aerogel as a Host for Dendrite‐Free Lithium‐Metal Anode and Efficient Sulfur Cathode in Li–S Full Cells
Authors: He Jiarui , Manthiram Arumugam
Published: September 2020

Lithium–sulfur batteries are appealing due to their high energy density and low cost. However, their commercial viability is challenged by uncontrollable dendritic Li growth and severe polysulfide shuttling during cycling. Here, a 3D framework coupling lithiophilic and catalytic CoSe nanoparticles with conductive carbon nanowires (CoSe@C) as an efficient host both for lithium and sulfur is reported. As a cathode host, CoSe@C offers highly efficient catalytic activity for polysulfide redox. As a rationally designed matrix with a high affinity for Li, CoSe@C guides a homogenous growth of Li within the 3D framework, which effectively suppresses dendritic Li growth. As a result, the CoSe@C/Li anode exhibits an ultralong lifespan of > 3000 h with a low overpotential of <23 mV. Remarkably, a full cell with a S/CoSe@C cathode and a CoSe@C/Li anode with a low negative to positive electrode capacity (N/P) ratio of ≈4 exhibits long cycle life of over 600 cycles with a high areal capacity of 5.8 mA h cm−2. It also remains stable after 50 cycles even with lean electrolyte (E/S: 4.5 µL mg−1) and a low N/P ratio of ≈4. This work offers new insights and opportunities for developing dendrite‐free, high‐performance Li–S battery technology.