bluuebunny/crossref_metadata_2025 huggingface dataset:
Recombinant Co-Expression of Collagen A1 (I) Fragment with the Prolyl 4-Hydroxylases (P4H) Subunits in Komagataella phaffii
Authors: Avci Esra , Kesmen Zülal
Published: January 2021

Recombinant collagen and collagen-like products are increasingly replacing animal-sourced collagen that is difficult to produce in safe and standard quality. In this study to produce hydroxylated collagen, a 400 base pair collagen fragment of the bovine COL1A1 gene was co-expressed with prolyl-4-hydroxylase subunit α (P4Hα) and prolyl-4-hydroxylase subunit β(P4Hβ) encoding the P4H enzyme in Komagataella phaffii. For this purpose, each target gene was inserted into the pPICZαA vector and then cloned in E. coli DH5α cells. Subsequently, co-expression vectors were constructed using recombinant vectors isolated from positive clones according to the in vitro multimer ligation method. All recombinant expression and co-expression vectors were transformed into K. phaffii X33 cells by electroporation. The results of reverse transcriptase-polymerase chain reaction (PCR) proved that all target genes were transcribed by recombinant strains. The expression of recombinant proteins was performed for 96 hours by methanol-fed cultivation, and the concentration of the purified proteins from the culture medium was measured by the His-Tag enzyme-linked immunosorbent assay (ELISA) method. The concentrations of rP4Hα and rP4Hβ, and rCol1 proteins expressed individually by recombinant strains were determined to be 10.69 µg/L, 10.74 µg/L, and 8.61 µg/L, respectively, while the concentrations of co-expressed rP4Hα/β and rP4Hα/β/rCol1 proteins were 7.82 µg/L and 5.02 µg/L, respectively. These results showed that the target genes were successfully expressed and co-expressed in the recombinant K. phaffii cell.
Probiotics as Agents of Health Improvement, Infection Control and Diseases Treatment: A Review
Authors: Gbadamosi Francis A. , Akaniro Ifunanya R. , Olaitan Morufat O. , Nnamocha Theresa O.
Published: January 2021

Aims: This review presents valuable information on the contribution of probiotics to the improvement of health and quality of life.

Background: Due to their roles in normal physiology and impacts on human health, probiotics have become a subject of great interests especially in the field of Microbiology. The results of several well-designed clinical studies have shown probiotics to be reliable therapeutic option for the prevention, treatment and control of various health conditions; gastrointestinal diseases, respiratory diseases, neurological disorders, depressive symptoms and autoimmune disorders. Probiotics enhance gastrointestinal tract (GIT) health via vitamins production and supply to the human host and have also been reported to improve immune function thus, inhibiting pathogen invasion and colonization/development. Some show direct/indirect immune modulating capabilities by enhancing mucosal barrier functions, modulating sensory motor functions and delivering antigens. Many probiotic foods possess antioxidant properties that enable them to withstand oxidative stress and strengthen hosts’ anti oxidative defense mechanism.

Findings/Conclusion: The potential application of probiotics in functional foods and pharmaceuticals could demonstrate the improvement of health and quality of life.
Assessment of Stabilized Silt Clay Sand with Oil Palm Fibre Bunch (OPFB) Local Fibre for Slope Foundations: A Case of Coastal Soils of Mombasa, Kenya
Authors: Makone Jared Kambaga , Wekesa Ezra
Published: January 2021

Improvement of shear strength parameters is essential for designing the OPFB fiber mix with silt clay sand for slope stability. The objective of this study was to assess the stabilized silt clay with oil palm fibre bunch (OPFB) local fibre for slope foundation. Series of laboratory tests were conducted on various materials under study and the results revealed that, OPFB mix can be used as an additive to cement for purpose of improving engineering properties of the Silt Clay sand to cut down costs without compromising the set standards. It was established that, the shear strength parameters of the soil-fibre mixture (φ and C) can be improved significantly up to an optimum and reach a certain point where it starts to decline. The shear stress–strain curves obtained from the CU triaxial tests for reinforced sands with 30 mm fibre length together with those for unreinforced silty sand were compared; the result indicated that, fibre-reinforced specimen showed higher deviator stress at 0.25% fibre and reduces at 0.5% fibre. The strain corresponding to the peak deviator stress was increased by fibre content. Patterns of stress–strain curves for all reinforcedsamples indicated improvement in the deviator stress for all compositions and fibre content. Deviator stress of fibre-reinforced soil showed a slight increase with increasing pore pressure. The increase of the fibre content caused an increase in pore water pressure due to inclination of specimens to decrease the volume. Changes in the shear strength of fibre-reinforced soil indicated that soil strength parameters (internal friction angle φ’ and cohesion C’) increase as the internal friction surface increases between fibre and soil at certain point.
Effects of Computer Simulation Package on Academic Performance of Senior Secondary School Students in Some Science Concepts in Ekiti State, Nigeria
Authors: Alake Ese Monica , Olojo Jethro Oludare
Published: January 2021

Use of computer simulated games among children/students is common and science students are not left out. Whereas poor performance and dwindling enrolment in science subjects have been observed among students in Nigeria, not much evidence has emerged at solving the problems from computer simulation mode of teaching. This study was designed to determine the effects of computer simulation package (CSP) on academic performance of senior secondary school students on the concepts of pollution and energy. Using multi-stage purposive and simple random sampling technique, six hundred (600) Senior Secondary (SS) class two students were selected from twelve co-educational schools consisting of four (4) schools in each of the senatorial districts of the State  and fifty (50) students  participated. Three hundred (300) students each were used for experimental and control groups. A validated Students’ Achievement Test (SAT) instrument, having 30 multiple choice items was used to generate pre-test and post-test data. Analysis of Covariance (ANCOVA) was used to test each of the hypotheses at 0.05 level of significance. Findings showed that the use of computer simulation package (CSP) has significant effect on students’ academic performance (F-cal 955.93, P = 0.00*< 0.05) while gender showed no significant influence on students’ performance (F-cal 1.03, P = 0.312 >0.05). Thus, science teachers should be trained and retrained in seminars, workshop and conferences on the use of computer simulation packages in order to encourage personalized learning among science students.
Evaluation as Disintegrant, Acetone-dehydrated Pre-Gelatinized Starch of Arthocarpus altilis Fruits in Oral paracetamol Tablets
Authors: Uwah T. O. , Effiong D. E. , Akpabio E. I. , Jacob G. , Awa I.
Published: January 2021

Introduction: Modifying natural polymers have imparted desirable properties making them suitable as pharmaceutical additives.

Aim: This research work was to prepare pre-gelatinized breadfruit starch using acetone to reduce drying time and energy expended. The modified starch was evaluated as a disintegrant in paracetamol oral compacts.

Methods: Starch from unripe mature bread fruit was pre-gelatinized, precipitated with acetone to reduce drying time. Native and pre-gelatinized starches were characterized for micromeritics, compatibility studies with test drug using Fourier Transform Infra-Red (FT-IR) and water interaction properties (viscosity, swelling power and hydration capacity). Paracetamol granules formed by wet granulation were compacted incorporating starches as disintegrant intragranularly, extragranularly and combining both methods. Disintegration and dissolution studies done.

Results: Pre-gelatinization did not alter the native starch chemically and their pH were within pharmaceutical limits. The disintegration efficiency ratio (DER) for the P2 and P3 (tablet batches with pre-gelatinized starches) compared favourably with that of corn starch. Also, the dissolution kinetics of the breadfruit starches followed the Hixson Crowel’s model while that of reference corn starch was best described by the Higuchi kinetic model.

Conclusion: Breadfruit starch is edible and the properties of its pre-gelatinized form as a disintegrant compares favourably with corn starch BP. It could be an good alternative as pharmaceutical excipient.
Ubiquitin‐independent proteasomal degradation of Spindlin‐1 by the E3 ligase HACE1 contributes to cell–cell adhesion
Authors: Palicharla Vivek Reddy , Gupta Devanshi , Bhattacharya Debjani , Maddika Subbareddy
Published: January 2021

HECT‐E3 ligases play an essential role in catalyzing the transfer of ubiquitin to protein substrates. The noncatalytic roles of HECT‐E3 ligases in cells are unknown. Here, we report that a HECT‐E3 ligase, HACE1, functions as an adaptor independent of its E3 ligase activity. We identified Spindlin‐1, a histone reader, as a new HACE1‐associated protein. Interestingly, we found that HACE1 promotes Spindlin‐1 degradation via the proteasome in an ubiquitination‐independent manner. Functionally, we demonstrated that the loss of HACE1 results in weak cell–cell adhesion due to Spindlin‐1‐mediated accumulation of GDNF, a negative regulator of cell adhesion. Together, our data suggest that HACE1 acts as a molecular adaptor and plays an important noncatalytic role in presenting selected substrates directly to the proteasome for degradation.
Amyloid‐β, cortical thickness, and subsequent cognitive decline in cognitively normal oldest‐old
Authors: Pelkmans Wiesje , Legdeur Nienke , ten Kate Mara , Barkhof Frederik , Yaqub Maqsood M. , Holstege Henne , van Berckel Bart N. M. , Scheltens Philip , van der Flier Wiesje M. , Visser Pieter Jelle , Tijms Betty M.
Published: January 2021

Objective

To investigate the relationship between amyloid‐β (Aβ) deposition and markers of brain structure on cognitive decline in oldest‐old individuals with initial normal cognition.

Methods

We studied cognitive functioning in four domains at baseline and change over time in fifty‐seven cognitively intact individuals from the EMIF‐AD 90+ study. Predictors were Aβ status determined by [18F]‐flutemetamol PET (normal = Aβ − vs. abnormal = Aβ+), cortical thickness in 34 regions and hippocampal volume. Mediation analyses were performed to test whether effects of Aβ on cognitive decline were mediated by atrophy of specific anatomical brain areas.

Results

Subjects had a mean age of 92.7 ± 2.9 years, of whom 19 (33%) were Aβ+. Compared to Aβ−, Aβ+ individuals showed steeper decline on memory (β ± SE = −0.26 ± 0.09), and processing speed (β ± SE = −0.18 ± 0.08) performance over 1.5 years (P < 0.05). Furthermore, medial and lateral temporal lobe atrophy was associated with steeper decline in memory and language across individuals. Mediation analyses revealed that part of the memory decline observed in Aβ+ individuals was mediated through parahippocampal atrophy.

Interpretation

These results show that Aβ abnormality even in the oldest old with initially normal cognition is not part of normal aging, but is associated with a decline in cognitive functioning. Other pathologies may also contribute to decline in the oldest old as cortical thickness predicted cognitive decline similarly in individuals with and without Aβ pathology.
Physical Inactivity and Incident Depression in a Multiracial, Multiethnic Systemic Lupus Erythematosus Cohort
Authors: Patterson Sarah L. , Trupin Laura , Yazdany Jinoos , Dall'Era Maria , Lanata Cristina , Dequattro Kimberly , Hartogensis Wendy , Katz Patricia
Published: January 2021

Objective

Physical activity is known to improve depressive symptoms. The present study was undertaken to examine physical inactivity as a predictor of incident depression in systemic lupus erythematosus (SLE).

Methods

Data derive from the California Lupus Epidemiology Study (CLUES), a longitudinal cohort with confirmed SLE diagnoses. Physical inactivity was assessed from a single item, “I rarely or never do any physical activities,” and depressive symptoms by the 8‐item Patient Health Questionnaire (PHQ‐8). Analysis included those not depressed at baseline (PHQ‐8 score <10) who completed an in‐person baseline assessment and at least 1 follow‐up visit (n = 225). Incident depression was defined as a PHQ‐8 score of ≥10 at follow‐up. Cox proportional hazards regression modeled incident depression over 2 years as a function of baseline physical inactivity, controlling for age, sex, race, income, comorbidities, disease activity, and disease damage.

Results

At baseline, the mean ± SD age of the participants was 45 ± 15 years, 88% were female, and 70% identified as non‐White. Mean PHQ scores for those without depression at baseline did not differ by activity status, but those who were inactive at baseline were significantly more likely to develop depression over the next 2 years (hazard ratio [HR] 2.89 [95% confidence interval (95% CI) 1.46–5.71]). After adjusting for covariates, the association remained strong, including a >3‐fold increased risk of incident depression among the sedentary group (HR 3.88 [95% CI 1.67–9.03]).

Conclusion

In this diverse SLE cohort, a simple question about physical inactivity was highly predictive of incident depression over the subsequent 2 years. Results suggest an urgent need for approaches to reduce sedentary behavior in this high‐risk population.
Modeling 3D Human Tumor Lymphatic Vessel Network Using High‐Throughput Platform
Authors: Lee Somin , Kang Habin , Park Dohyun , Yu James , Koh Seung Kwon , Cho Duck , Kim Da‐Hyun , Kang Kyung‐Sun , Jeon Noo Li
Published: January 2021

The lymphatic vessel (LV) plays an important role in cancer biology as a major route for tumor metastasis. Whereas, recent oncoimmunological approaches have focused its role in immune surveillance. In response to the emerging topics of lymphatic vascular biology, physiologically relevant human cell‐based in vitro model is in high demand. This study introduces a 3D in vitro model of human LV within tumor immune microenvironment (TIME) using an injection‐molded plastic array culture platform (Lymph‐IMPACT). Through spontaneous capillary flow‐driven patterning of 3D cellular hydrogel and optimized cellular composition, the platform enables robust and reproducible formation of self‐organized LV in vitro. This co‐culture model recapitulates cancer cell type‐dependent morphogenesis of LV in vitro. Moreover, the robustness of the model enables high‐content analysis on the effect of anti‐VEGFR3 drug depending on the existence of blood vessels or different types of cancer cells. By virtue of high perfusability of 3D lumenized in vitro LV, a trans‐endothelial migration of cytotoxic primary lymphocytes, which is one of the critical processes in anti‐tumor immunology, is recapitulated within reconstructed melanoma TIME. From drug testing to cellular migration assays using the high‐throughput platform, the Lymph‐IMPACT demonstrates its powerful potential to be applied on investigating lymphatic‐related strategies for cancer therapeutics.
Spatiotemporal Control Over Multicellular Migration Using Green Light Reversible Cell–Cell Interactions
Authors: Nzigou Mombo Brice , Bijonowski Brent M. , Rasoulinejad Samaneh , Mueller Marc , Wegner Seraphine V.
Published: January 2021

The regulation of cell–cell adhesions in space and time plays a crucial role in cell biology, especially in the coordination of multicellular behavior. Therefore, tools that allow for the modulation of cell–cell interactions with high precision are of great interest to a better understanding of their roles and building tissue‐like structures. Herein, the green light‐responsive protein CarH is expressed at the plasma membrane of cells as an artificial cell adhesion receptor, so that upon addition of its cofactor vitamin B12 specific cell–cell interactions form and lead to cell clustering in a concentration‐dependent manner. Upon green light illumination, the CarH based cell–cell interactions disassemble and allow for their reversion with high spatiotemporal control. Moreover, these artificial cell–cell interactions impact cell migration, as observed in a wound‐healing assay. When the cells interact with each other in the presence of vitamin B12 in the dark, the cells form on a solid front and migrate collectively; however, under green light illumination, individual cells migrate randomly out of the monolayer. Overall, the possibility of precisely controlling cell–cell interactions and regulating multicellular behavior is a potential pathway to gaining more insight into cell–cell interactions in biological processes.
Dual Systems for Enhancing Control of Protein Activity through Induced Dimerization Approaches
Authors: Pearce Sarah , Tucker Chandra L.
Published: January 2021

To reveal the underpinnings of complex biological systems, a variety of approaches have been developed that allow switchable control of protein function. One powerful approach for switchable control is the use of inducible dimerization systems, which can be configured to control activity of a target protein upon induced dimerization triggered by chemicals or light. Individually, many inducible dimerization systems suffer from pre‐defined dynamic ranges and overwhelming sensitivity to expression level and cellular context. Such systems often require extensive engineering efforts to overcome issues of background leakiness and restricted dynamic range. To address these limitations, recent tool development efforts have explored overlaying dimerizer systems with a second layer of regulation. Albeit more complex, the resulting layered systems have enhanced functionality, such as tighter control that can improve portability of these tools across platforms.
Stress Mapping on Ultrahigh Strength Steel Cut Edges
Authors: Lindberg Fredrik , Ryde Lena , Brask Johannes , Hörnström Sven Erik , Östberg Jonas , Müller Timo
Published: January 2021

Metal shearing operations are a stage in the process route from steel plate to finished product which may introduce stress that can be detrimental at later stages of the products life. This is especially true in connection with hydrogen embrittlement‐induced fracture. One prerequisite for hydrogen embrittlement is concentrations of residual stresses. During cutting operations, residual stresses originating from plastic deformation are introduced. Herein, how pencil‐beam high‐energy X‐ray diffraction using synchrotron radiation can be used to map stresses down to the microscale is demonstrated. The effects of alternative cutting methods, namely, milling after shearing and laser cutting, that are believed to relieve or to lessen the stress effect on the materials, are also presented. The residual stress measurements using diffraction data are supported using high‐resolution hardness measurements.
An Analytical Model for Oblique Cross Section Nanoindentation of Ion‐Irradiated Metallic Alloys Based on Studies of Oxide Dispersion Strengthened Steel MA957
Authors: Bhattacharyya Dhriti , Hurt Christopher , Xu Alan , Ionescu Mihail
Published: January 2021

Herein, oblique cross section (OCS) nanoindentation is used to measure the hardness changes in He2+ ion‐irradiated oxide dispersion strengthened (ODS) steel MA957, to obtain the hardness profile through the thickness, and correlate it with the damage dose profile. Following this, the dispersed barrier hardening (DBH) model is implemented to calculate the hardness of each layer of the irradiated material, based on the displacement damage and He concentration from simulations. Next, a simplified analytical model for the measured hardness at different depths is developed with the assumption that the plastic zone under the indenter is hemispherical and the hardness measured at any given depth depends on the average hardness of the plastic zone volume. This analytical model is implemented with the help of a program written in MATLAB. The calculated hardness profile is compared with the experimental profile, and it is found to be in reasonably good agreement for different energies of the irradiating He ions. This model can be used not only for ion‐irradiated materials with varying doses in different layers but also for other metallic materials with surface layers having diffuse interfaces.
Mechanical and Acoustic Behavior of 3D‐Printed Hierarchical Mathematical Fractal Menger Sponge
Authors: Kushwaha Brijesh , Dwivedi Kush , Ambekar Rushikesh S. , Pal Varinder , Jena Dibya Prakash , Mahapatra Debiprosad Roy , Tiwary Chandra Sekhar
Published: January 2021

Structural materials that feature hierarchical architectures (e.g., fractals) display remarkable mechanical properties. Menger sponge is one of the fractal geometries defined in Mathematics and made up of a unit cube with three orthogonal cavities. The precise fractal dimensions are fabricated using 3D printing. Experiments and simulations are conducted on the structure under uniaxial compression. The effect of increasing the levels of orthogonal cavities of the Menger sponge structure as well as the changing shape of the cavity are studied. The results show an interesting correlation between mechanical properties and the effective density of the structure. Multiple levels of hierarchy are analyzed in terms of different cavity shapes. These comparisons suggest that hierarchical structures are used to obtain better performance with a lower effective density of the resulting structures. Damage initiation for the different cavity shapes shows how each of the cavity shapes behaves under compressive loading. Herein, it is discerned how hierarchical architecture is used to access the unique properties of structures, providing insight into the role of design in regulating the mechanical properties of such mechanical structures. The result of acoustic investigation shows that it is a better absorber as compared with commercial sponge in the low‐frequency regime.
A Graftable Quaternary Ammonium Biocidal Polymer Reduces Biofilm Formation and Ensures Biocompatibility of Medical Devices
Authors: Bouloussa Houssam , Saleh‐Mghir Azzam , Valotteau Claire , Cherifi Chahrazad , Hafsia Narjes , Cohen‐Solal Martine , Court Charles , Crémieux Anne‐Claude , Humblot Vincent
Published: January 2021

A quaternized polyvinylpyridine (Q‐PVP) polymer methanolic solution synthesized in a single step is used to covalently graft titanium surfaces. Q‐PVP is quaternized with varying N+/N ratios. 1 cm2 pure titanium plates are polished and activated. Treated samples are grafted by spin coating or dip‐coating (grafting‐to method). Surfaces are characterized by X‐ray photoelectron spectroscopy, polarization modulation reflection absorption IR spectroscopy, atomic force microscopy, scanning electron microscopy, and surface charge density calculation. Polymer leaching is assessed at 7 days. Biocompatibility is assessed on MC3T3 and L929 cells (MTT‐assay) and SEM. In vitro antibacterial activity is assessed on methicillin‐resistant Staphylococcus aureus (MRSA) at 1 and 24 h (37 °C in brain heart infusion) and at 7 days in a biofilm model. Polymers exceeding 31.3 ± 0.7% quaternization led to bactericidal surfaces. Bactericidal activity increased with surface cationic density. Surface cationic density and biocompatibility are inversely correlated. Polymers with 44.6 ± 1.2% quaternization are antibacterial and biocompatible. High‐density Q‐PVP inhibited MRSA biofilm formation. Q‐PVP is a promising candidate for antibacterial surface modification. Further in vivo studies are required.
Scalable Pulsed Laser Deposition of Transparent Rear Electrode for Perovskite Solar Cells
Authors: Smirnov Yury , Schmengler Laura , Kuik Riemer , Repecaud Pierre‐Alexis , Najafi Mehrdad , Zhang Dong , Theelen Mirjam , Aydin Erkan , Veenstra Sjoerd , De Wolf Stefaan , Morales‐Masis Monica
Published: January 2021

Sputtered transparent conducting oxides (TCOs) are widely accepted transparent electrodes for several types of high‐efficiency solar cells. However, the different sputtering yield of atoms makes stoichiometric transfer of target material challenging for multi‐compounds. Additionally, the high kinetic energies of the arriving species may damage sensitive functional layers beneath. Conversely, pulsed laser deposition (PLD) is operated at higher deposition pressures promoting thermalization of particles. This leads to stoichiometric transfer and additionally reduces the kinetic energy of ablated species. Despite these advantages, PLD is rarely used within the photovoltaic community due to concerns about low deposition rates and the scalability of the technique. In this study, wafer‐scale (4‐inch) PLD of high‐mobility Zr‐doped In2O3 (IZrO) TCO for solar cells is demonstrated. IZrO films are grown at room temperature with deposition rate on par with RF‐sputtering (>4 nm min−1). As‐deposited IZrO films are mostly amorphous and exhibit excellent optoelectronic properties after solid phase crystallization at <200 °C. 100‐nm thick films feature a sheet resistance of 21 Ω◻−1 with electron mobilities ≈70 cm2 V−1s−1. PLD‐grown IZrO is applied as rear electrode in efficient semi‐transparent halide perovskite solar cells leading to the improved stabilized maximum power point efficiency (15.1%) as compared to the cells with sputtered ITO electrodes (11.9%).
A 3D Printed Wearable Bioelectronic Patch for Multi‐Sensing and In Situ Sweat Electrolyte Monitoring
Authors: Kim Taeil , Yi Qian , Hoang Emily , Esfandyarpour Rahim
Published: January 2021

Wearable biosensors′ ability to measure continuous health parameters gives promise to healthcare with great potentials to advance precision medicine. The stability and balance within the human body are critical for organ systems′ normal functions. The imbalance of electrolytes may lead to several diseases such as hypertension, heart failure, and kidney diseases. Sweat electrolytes analysis, that is, the analysis of one of the noninvasively accessible biofluids, can provide important information about physiologically relevant quantities, and a combination of them can be employed for comprehensive studies. However, wearable biosensors′ large‐scale utilization for extensive population monitoring requires rapid, reliable, low‐cost, and high‐throughput integration of such platforms. Here, 3D‐printing technology is adapted to develop a novel, multiplex, low‐cost, and mechanically flexible all‐inclusive integrated wearable (AIIW) patch, which contains 3D‐printed flexible sensors along with flexible wearable‐microfluidic sample handling (WMFSH) units, integrated in a few hours. The AIIW patch is fully characterized, and its utility for noninvasive and continuous health monitoring is successfully demonstrated by simultaneous ex situ and in situ measuring of multiple electrolyte levels in sweat. This work is envisioned as another step toward enabling personalized health monitoring practices by implementing 3D‐printing technology in the easy and low‐cost development of customized integrated, flexible wearable biosensing platforms to monitor an individual's health parameters.
Combining Soft with Hard Condensed Matter for Circular Polarized Light Sensing and Logic Operations
Authors: Grey Paul , Chapa Manuel , Alexandre Miguel , Mateus Tiago , Fortunato Elvira , Martins Rodrigo , Mendes Manuel J. , Pereira Luís
Published: January 2021

The study shows the incorporation of chiral nematic photonic cellulose nanocrystal (CNC) films, well known for their adaptive character of selective reflection of circular polarized light (CPL), and silicon‐based thin‐film photodiodes, thus achieving a light sensor capable of discriminating right‐ from left‐handed CPL. The circular polarization (CP) response is maximum for specific wavelengths in the green‐to‐red region. When subjected to these wavelengths, they produce photocurrents that are over 50% distinct between the two CP states. Proper signal processing, thus, yields a binary output depending on the handedness of the light. Through the addition of monovalent salt to the initial CNC suspension, a blueshift to the photonic band gap is induced, enabling a larger wavelength gamut and application possibilities. The measured results are then used as a basis for electromagnetic simulations that show remarkable consistency with the experimental results, thus defining a new tool that can be used to efficiently optimize the devices’ response. Fast transient responses to CPL are shown with possible logic operations, as well as humidity sensing. The developed devices are, thus, applicable in areas as diverse as imaging, CPL sensing, optoelectronic counterfeiting, and information processing with logic states that depend solely on the handedness of the incident light.
Transition‐Metal‐Free Base‐Controlled C−N Coupling Reactions: Selective Mono Versus Diarylation of Primary Amines with 2‐Chlorobenzimidazoles
Authors: Sang Wei , Gong Yan‐Yan , Cheng Hua , Zhang Rui , Yuan Ye , Fan Guang‐Gao , Wang Zhi‐Qin , Chen Cheng , Verpoort Francis
Published: January 2021

Herein, a base‐controlled protocol was developed for the C−N coupling of primary amines and 2‐chlorobenzimidazoles, affording a handful of secondary or tertiary amines in a selective fashion. Moreover, this protocol was realized under transition‐metal‐free conditions, and the variation of the base from iPr2NH to LiOtBu completely switched the selectivity from monoarylation to diarylation. Further investigations elucidated that the variety, intrinsic basicity and amount of the utilized bases considerably affected these reactions.

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Palladium‐Catalyzed Carbonylation in the Synthesis of N‐Ynonylsulfoximines
Authors: Ma Ding , Wang Chenyang , Kong Deshen , Tu Yongliang , Shi Peng , Bolm Carsten
Published: January 2021

Palladium‐catalyzed carbonylation reactions with Cr(CO)6 as carbonyl source are key for the preparation of N‐ynonylsulfoximines from NH‐sulfoximines and bromoalkynes. The couplings proceed at room temperature with a wide range of substrate combinations affording the corresponding products in good yields.

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Resistance Theory of General 2 × n Resistor Networks
Authors: Zhang Yi‐Tian , Hu Xuan , Chen Hai‐Xiang , Wang Ming‐Yue , Chen Wan‐Jiao , Fang Xin‐Yu , Tan Zhi‐Zhong
Published: January 2021

Here the problem of equivalent resistance of general 2 × n‐order resistor networks with four different resistor parameters is investigated, and innovations in theory and method are made. Here, the second‐order matrix equation model and boundary condition equation model are established by the RT‐I technique (recursion–transform theory based on current parameters), and the general solution and the special solution of the matrix equation are given by using the matrix transformation method. The current distribution law in the circuit is obtained, and three equivalent resistance formulas of general ‐order resistor networks are obtained. Finally, by analyzing and discussing the special case of the conclusion, the relationship between different resistances is obtained, and the results are compared with those of other literatures.
Trap Reduction through O3 Post‐Deposition Treatment of Y2O3 Thin Films Grown by Atomic Layer Deposition on Ge Substrates
Authors: Kim Dong Gun , Kwon Dae Seon , Lim Junil , Seo Haengha , Kim Tae Kyun , Lee Woongkyu , Hwang Cheol Seong
Published: January 2021

For Ge‐based metal‐oxide‐semiconductor field‐effect transistor application, high‐k Y2O3 thin films are deposited on Ge single‐crystal substrate using atomic layer deposition. The primary drawbacks of a metal‐oxide‐semiconductor capacitor with pristine Y2O3 are large hysteresis and high leakage current. Through forming gas annealing (FGA), the leakage current can be reduced by approximately three orders of magnitude, along with the reduction of interface trap density. However, there is still a large hysteresis in the capacitance–voltage curves. O3 post‐deposition annealing (OPA) is used to solve the problem. The formation of the YGeOx interfacial layer through OPA and the reduction of the defect level of the Y2O3 thin film effectively decrease the hysteresis, which also decreases the leakage current. Additionally, the hysteresis is 690 mV when only FGA is performed. However, it is further reduced to 260 mV through OPA. Moreover, the remote oxygen scavenging effect using TiN/Pt electrodes prevents an unintentional increase in equivalent oxide thickness (EOT). The 4.7 nm thick Y2O3 film results in an EOT of 1.77 nm and leakage current density of 2.1 × 10−7 A cm−2 (at flat band voltage—1 V) after the OPA.
Hybrid Memory Device (Memory/Selector) with Scalable and Simple Structure for XNOR‐Based Neural Network Applications
Authors: Sung Changhyuck , Kim Seong Hun , Kwak Myounghoon , Lee Donghwa , Hwang Hyunsang
Published: January 2021

This study investigates the electrical behavior of a hybrid memory device with both memory and selector characteristics. Electrical measurements and simulations indicate that the electrical behaviors (nonvolatile characteristics in Al2O3 layers and volatile characteristics in TiO2 layers) are linked to the stability of the conductive filament (CF) used. The binding energy between the Ag atoms in the CF is crucial for achieving nonvolatile or volatile characteristics. Thus, the hybrid memory device exhibits tunable threshold‐voltage characteristics and a consistent off‐state without requiring an additional selector device. Furthermore, the buffer metal layer between the active electrode and oxide layer affects the filament‐formation process in terms of the switching time. Experimental results show that the buffer layer significantly affects ion motion, such as redox reactions and ion migration. Thus, hybrid memory devices with a Zr buffer layer can solve the voltage–time dilemma, enabling fast and low‐voltage switching. Robust XNOR‐based neural network applications are developed using hybrid memory devices in a cross‐point array with characteristics such as scalability, simple structure, and excellent switching characteristics. By carefully considering the on–off ratio and device variability, hybrid memory devices can ensure reliable operation with a high pattern recognition accuracy in XNOR‐based neural neuromorphic hardware systems.
Crystal Reorientation and Amorphization Induced by Stressing Efficient and Stable P–I–N Vacuum‐Processed MAPbI3 Perovskite Solar Cells
Authors: Kaya Ismail C. , Zanoni Kassio P. S. , Palazon Francisco , Sessolo Michele , Akyildiz Hasan , Sonmezoglu Savas , Bolink Henk J.
Published: January 2021

Herein, the long‐term stability of vacuum‐deposited methylammonium lead iodide (MAPbI3) perovskite solar cells (PSCs) with power conversion efficiencies (PCEs) of around 19% is evaluated. A low‐temperature atomic layer deposition (ALD) Al2O3 coating is developed and used to protect the MAPbI3 layers and the solar cells from environmental agents. The ALD encapsulation enables the MAPbI3 to be exposed to temperatures as high as 150 °C for several hours without change in color. It also improves the thermal stability of the solar cells, which maintain 80% of the initial PCEs after aging for ≈40 and 37 days at 65 and 85 °C, respectively. However, room‐temperature operation of the solar cells under 1 sun illumination leads to a loss of 20% of their initial PCE in 230 h. Due to the very thin ALD Al2O3 encapsulation, X‐ray diffraction can be performed on the MAPbI3 films and completed solar cells before and after the different stress conditions. Surprisingly, it is found that the main effect of light soaking and thermal stress is a crystal reorientation with respect to the substrate from (002) to (202) of the perovskite layer, and that this reorientation is accelerated under illumination.
Agronomic performance of interspecific Paspalum hybrids under nitrogen fertilization or mixed with legumes
Authors: da Motta Eder A. Minski , DallAgnol Miguel , Rios Esteban F. , de Souza Cleber H. Lopes , Weiler Roberto L. , Brunes André Pich , Simioni Carine , Rockenbach de Ávila Mariana , Neto Douglas , Felix Leonardo Duarte , Nunes dos Santos Tamyris
Published: January 2021

Nitrogen supply and mixtures with legumes affect agronomic performance of pastures, and both practices can guide breeding decisions in Paspalum hybrids. The goals of this study were: (a) quantify herbage accumulation (HA), leaf accumulation (LA), cold tolerance, and N use efficiency (NUE) in P. plicatulum × P. guenoarum hybrids subjected to N fertilization or grown in a mixture with legumes; (b) compare the grass–legume system to a grass–N fertilizer system; and (c) select the best hybrid for future cultivar releases. A randomized complete block design with three replications and a split‐plot treatment arrangement was used for 2 yr, with five N rates (0, 60, 120, 240, and 480 kg N ha−1) and a grass–legume mixture [grass + white clover (Trifolium repens L.) + birdsfoot trefoil (Lotus corniculatus L.)] as whole plots, and six genotypes as subplots (hybrids: 1020133, 102069, 103084, 103061; and controls: P. guenoarum ‘Azulão’ and Megathyrsus maximus ‘Aruana’). Higher N rates increased HA, LA, and cold tolerance. Higher NUE was obtained between 60 and 120 kg N ha−1. In the grass–legume mixture HA was similar to the rates of 60 and 120 kg N ha−1. Hybrid 1020133 had HA similar to the controls, LA greater than Aruana, and greater cold tolerance and NUE at 60 kg N ha−1 than Azulão and Aruana. Hybrid 1020133 should be selected for further animal performance studies. The agronomic performance of perennial pastures can be improved through N management, and NUE should be a selection criterion in forage breeding.
Greenhouse gas emissions from an irrigated cropping rotation with dairy manure utilization in a semiarid climate
Authors: Dungan Robert S. , Leytem April B. , Tarkalson David D.
Published: January 2021

This long‐term study was established to increase knowledge of greenhouse gas (GHG) emissions from irrigated cropping systems utilizing dairy manure solids and compost in semiarid southern Idaho. The objective of this field study was to determine the effect of synthetic N fertilizer (urea or SuperU [enhanced‐efficiency synthetic fertilizer]), composted dairy manure, dairy manure (fall or spring applied), and a control (no fertilizer or manure) on nitrous oxide (N2O), carbon dioxide (CO2), and methane (CH4) emissions over the growing season. The fertilizer and manure treatments were not applied to alfalfa (Medicago sativa L.) (2017) but were applied to corn (Zea mays L.) (2018; except SuperU) and barley (Hordeum vulgare L.) (2019). Cumulative N2O losses over the 3 yr ranged from 2.8 to 5.2 kg N2O‐N ha–1, with the fall and spring manure emitting the greatest amounts of N2O. Emission factors indicated that up to 0.79% of the total N applied was lost as N2O‐N during the growing seasons. Cumulative losses of CO2 and CH4 across the rotation were on average 12,170 kg CO2–C ha–1 and –0.77 kg CH4–C ha–1, respectively, with no significant differences among the treatments. Major N2O pulses were associated with early‐season irrigation events and incorporation of fertilizer and manure, but overall fluxes tended to be the greatest when soil temperatures were higher. Dairy manure and compost applications were also found to cause rapid and significant increases in soil organic carbon (SOC) in the top 30 cm of soil under corn and barley. Despite the fact that manure does cause elevated soil N2O emissions, it should be considered as an alternative to synthetic fertilizer use due to its ability to increase SOC and potentially help reduce the global warming potential.
Robust and efficient determination of saturation pressure from constant mass expansion data
Authors: Wang Mingyuan , Argüelles‐Vivas Francisco J. , Okuno Ryosuke
Published: January 2021

This article presents an improved method for the determination of saturation pressure from pressure‐volume data of constant‐mass expansion (CME) for hydrocarbon mixtures. The conventional methods rely on the direct observation of an incipient phase and/or the change in total compressibility of the fluid sample near the saturation pressure in CME; however, they are unreliable for volatile oils, gas condensates, and near‐critical fluids. The method developed in this research is to capture the expansion behavior of the overall fluid through the attraction and covolume parameters of the Peng–Robinson equation of state. The reliability of the new method is demonstrated by comparing it with the conventional methods in the case studies using 59 different fluids. It was the only method that could reliably identify saturation pressures for five volatile oils, 11 gas condensates, and one near‐critical fluid among the datasets tested.
MBD5‐related intellectual disability in a Vietnamese child
Authors: Le Thanh Nha Uyen , Ha Thi Minh Thi
Published: January 2021

The disruption of methyl‐binding domain protein 5 (MBD5) gene has been determined as a significant cause of a group of disorders known as MBD5‐associated neurodevelopmental disorder. Here, we report a novel pathogenic mutation, NM_001378120.1 (MBD5): c.217‐1G>C, occurring at the acceptor splicing site of intron 6 of the MBD5 gene identified in a Vietnamese child with intellectual disability, autistic‐like behaviors, and seizure. Phenotypic manifestations in this patient are highlighted with neurodevelopmental impairments whereas his facial dysmorphism is unremarkable. Our finding has enriched the understanding of the spectrum of MBD5 variants, a critical database for diagnosis, genetic counseling, and management of the patients with neurological diseases.
Pediatric medical genetics house call: Telemedicine for the next generation of patients and providers
Authors: Cohen Andrea J. , Shur Natasha , Starin Danielle , MacLeod Erin , Roshan Lal Tamanna , Leon Eyby , Regier Debra S.
Published: January 2021

In an era of increasing technology and interaction with the patient bedside, we explore the role of relocating the bedside from the hospital to the home using telemedicine. The COVID‐19 pandemic pushed telemedicine from small and pilot programs to widespread practice at an unprecedented rate. With the rapid implementation of telemedicine, it is important to consider how to create a telehealth system that provides both good care for patients and families while maintaining an excellent education environment for trainees of all levels. To this end, we developed telemedicine educational milestones to describe novel skills required to provide high quality telemedicine care, and allow trainees and clinical educators a metric by which to assess trainee progress. We also created methods and tools to help trainees learn and families feel comfortable in their new role as virtual collaborators. We envision a time when safety does not set the venue; instead the needs of the patient will dictate whether a virtual or in‐person visit is the right choice for a family. We expect that pediatric medical genetics and metabolism groups across the country will continue to set a standard of a hybrid care system to meet the unique needs of each individual patient, using telemedicine technology.
Female reproductive energetics in mantled howler monkeys (Alouatta palliata): A follow‐up study
Authors: Rangel Negrín Ariadna , Coyohua Fuentes Alejandro , de la Torre Herrera Amalia , Cano Huertes Beatriz , Reynoso Cruz Eduardo , Ceccarelli Enrico , Gómez Espinosa Eugenia E. , Chavira Ramírez David R. , Moreno Espinoza Diana E. , Canales‐Espinosa Domingo , Maya Lastra Natalia , Cruz Miros Pamela , Cañadas Santiago Samuel , Garau Sara , Dias Pedro A. D.
Published: January 2021

Objective

Reproduction entails several challenges to primate females, among which energetic costs are remarkable at certain stages of the reproductive cycle. Still, females may use behavioral and physiological strategies to cope with those challenges. We had previously reported covariation between female energetic condition through the reproductive cycle and time‐budget adjustments in mantled howler monkeys (Alouatta palliata). Accordingly, we suggested that behavioral flexibility allowed coping with the energetic challenges of reproduction. Subsequent evidence from the same population, however, suggested otherwise, so we performed a follow‐up study on the variation in female reproductive energetics based on a larger sample of females.

Methods

We studied 48 free‐ranging adult females at Los Tuxtlas (Mexico). We assessed energy balance via urinary C‐peptide concentrations (2717 urine samples), behavioral energy intake and expenditure (5728 sampling hours), and physiological energy expenditure via fecal triiodothyronine metabolites (fTH3; 3138 fecal samples).

Results

We found that energy balance varied among reproductive states: (a) cycling was a period of low C‐peptide concentrations; (b) the highest C‐peptide concentrations occurred during gestation; and (c) the beginning of lactation marked a notable decrease in C‐peptide concentrations, which then improved at mid‐lactation to again decline at lactation offset. These peaks and valleys in energy balance did not seem to be associated with variation in energy acquisition but were rather mirrored by activity levels and fTH3 during lactation.

Discussion

Energy balance was not preserved through the reproductive cycle, supporting previous contentions that the reproductive performance of female mantled howler monkeys may be energetically constrained. The contrast between these and results that we have previously reported, highlights the importance of conducting follow‐up studies to continually improve our understanding of the reproductive energetics of primate females.
Hand preference in unimanual and bimanual coordinated tasks in wild western lowland gorillas (Gorilla gorilla gorilla) feeding on African ginger (Zingiberaceae)
Authors: Tamura Masaya , Akomo‐Okoue Etienne François
Published: January 2021

Objectives

Bimanual coordinated behaviors are critical for detecting robust individual hand preference in nonhuman primates but are particularly challenging to observe in the wild. This study focuses on spontaneous feeding behavior on African ginger (Aframomum sp. and Renealmia sp.), which involves a unimanual task (reaching and pulling out a ginger stem) and a bimanual coordinated task (extracting pith from a ginger stem) by wild western lowland gorillas.

Materials and methods

Study subjects were 21 gorillas in the Moukalaba‐Doudou National Park, Gabon. We examined whether they exhibit significant hand preference at the individual and group levels for both tasks.

Results

Sixteen gorillas showed significant hand preference in the unimanual task, whereas all 21 individuals showed significant hand preference in the bimanual coordinated task. Hand preference was significantly stronger in the bimanual coordinated task than in the unimanual task. It is noteworthy that gorillas showed a significant right‐hand preference at the group level for the bimanual task (roughly 70% of the subjects).

Discussion

This study confirmed that bimanual coordinated tasks are more sensitive in detecting hand preferences in nonhuman primates. In addition to the bimanual nature of the task, the precision grip for processing and the importance of African ginger as a food resource might influence the expression of hand preference. Evidence of a group‐level right‐hand preference may support the “postural origins theory.” Because all wild African great apes feed on the pith of African ginger, comparing this task and its hand preferences can contribute toward a better understanding of the evolution of handedness in Hominidae.