bluuebunny/crossref_metadata_2025 huggingface dataset:
Climate Change Adaptation and Mitigation Measures Initiated by Farmers in Aravalli Hill Zone of Rajasthan, India
Authors: Jat Seema , Bhati D. S. , Choudhary Rekha , Rana Priyanka
Published: February 2023

Aims: To study about the adaptation and mitigation measures initiated by the farmers against climate change in local conditions.

Study Design: Ex-post-facto research design was followed.

Place and Duration of Study: The study was conducted at Department of Agricultural Extension and Communication, Bhagwant University, Ajmer during 2019-2022.

Methodology: The study was conducted in Aravalli Hill Zone of Rajasthan to understand adaptation & mitigation measures employed by farmers to the adverse effects of climate change. In the investigation region, 240 farmers were randomly selected.

Results: In the region 95.83 per cent of the farmers pursued that soil and water conservation was the most widely practiced strategy. Whereas, almost three fourths of the respondents were practicing adoption of drought tolerant and early maturing crop varieties were (75%), use of small-scale irrigation (73.75%), enhancing participatory forest management (73.33%) and afforestation/ reforestation (72.91%), while (70. 83%) practiced diversification of small ruminant animals and changing cropping calendar of agricultural activities. In the constants of  the maize crop adaptation measures against excess rainfall was 70.83 per cent of delayed sowing dates; this change in sowing date was adopted by the farmers and adaptation measures in maize crop against deficit rainfall observed by the investigator that 69.58 per cent of the farmers found that delayed sowing dates had affected them.

Conclusion: The local people employed different strategies to adapt the adverse effects of climate change, there were constraints that limit the farmer’s adaptation strategies i. e. lack of financial support, lack of climate information and lack of technical skills. Therefore, the local decision makers such as agricultural sector, microfinance sector, and meteorological agency should provide farmers credit access and climate information to reduce shortage of finance and lack of climate information. There is also need of providing training to the farmers on improved agricultural technology and market access to enhance their climate resilience conditions.
Acute Toxicity Assay and Anti-diabetic Activities of Shemmeco Extract in Drosophila melanogaster
Authors: Egene Emmamuel Ojochegbe
Published: February 2023

In this study the acute toxicity assay and anti- diabetic properties of Shemmeco extract were examined. The LC50 in this study was conducted using the concentrations: 5 mg, 10 mg, 25 mg, 50 mg, 100 mg, 250 mg, 500 mg, 1000 mg, 2500 mg and 5000 mg of extract, each per 10g fly diet. For ten days, Drosophila melanogaster was fed a high diet of sucrose (2.5 g/10 g diet) to elicit insulin resistance type 2 diabetes. The diabetic flies were treated with 5mg, 10mg, 25mg, 50mg and 250 mg per 10 g diet each of Shemmeco extract being safe concentrations from result of acute toxicity and 16mg of metformin/10g diet as standard drug. Glucose content significantly elevated (p<0.05) in diabetes untreated compared to control group. Metformin significantly declined (p<0.05) the glucose content of fruit flies treated with 5 mg (S1) of Shemmeco extract compared to diabetic untreated and metformin treated. The slight decline of glucose content of fruit flies treated with 5mg (S1) of Shemmeco extract therefore indicates that the extract is promising in the treatment of diabetes type 2 if developed further.
Modeling COVID-19 Pandemic by the \(\lambda\)ISR Volterra-Fredholm Integral Equation: A Case Study of South Africa
Authors: Warnapala Yajni , Gilbert Kate
Published: February 2023

Inspired by the COVID-19 pandemic, this paper investigates the feasibility of obtaining good convergence results for a nonhomogeneous Volterra-Fredholm integral equation model of the second kind. Volterra-Fredholm integral equations are often used to model infection and recovery of diseases in a population and can be used to model a pandemic or an endemic. This model uses a Volterra-Fredholm integral equation of the second kind to predict the number of individuals recovered from the COVID-19 pandemic in South Africa. The integral model was approximated by using the Gaussian Quadrature Method. The \(\lambda\)ISR model accounts for many variables of the pandemic including the number of initially infected individuals I0, susceptible individuals S0, and removed individuals R0. It also accounts for the initial recovery rate \(\gamma\), the infectivity of the virus \(\beta\) , removal rate \(\mu\) , and the total population of South Africa N. In addition to these, we also considered blood type S (x), and the rh factor \(\lambda\)(x) .

The model was constructed in “person-days,” which is the combined variable of time (t, days) and the number of individuals (x). Specific blood types and presence of the rh factor have been shown to have varying susceptibility to infection and severity of infection (requiring intubation), therefore this was an important parameter for this model [1,2].
Evaluation of Potentially Avoidable Acute Care Utilization Among Patients Insured by Medicare Advantage vs Traditional Medicare
Authors: Beckman Adam L. , Frakt Austin B. , Duggan Ciara , Zheng Jie , Orav E. John , Tsai Thomas C. , Figueroa Jose F.
Published: February 2023

Importance

Medicare Advantage plans have strong incentives to reduce potentially wasteful health care, including costly acute care visits for ambulatory care−sensitive conditions (ACSCs). However, it remains unknown whether Medicare Advantage plans lower acute care use compared with traditional Medicare, or if it shifts patients from hospitalization to observation stays and emergency department (ED) direct discharges.

Objective

To determine whether Medicare Advantage is associated with differential utilization of hospitalizations, observations, and ED direct discharges for ACSCs compared with traditional Medicare.

Design, Setting, and Participants

Cross-sectional study of US Medicare Advantage vs traditional Medicare beneficiaries from January 1 to December 31, 2018. Poisson regression models were used to compare risk-adjusted rates of Medicare Advantage vs traditional Medicare, controlling for patient demographic characteristics and clinical risk and including county fixed-effects. Data were analyzed between April 2021 and April 2023.

Main Outcomes and Measures

Hospitalizations, observation stays, and ED direct discharges for ACSCs.

Results

The study sample comprised 2 754 630 Medicare Advantage patients (mean [SD] age, 72.9 [9.9] years; 1 549 233 [56.2%] women; 1 926 437 [69.9%] White individuals) and 6 349 693 traditional Medicare patients (mean [SD] age, 72.3 [11.9] years; 3 479 387 [54.8%] women; 5 073 742 [79.9%] White individuals). Medicare Advantage patients had lower risk of hospitalization for ACSCs compared with traditional Medicare patients (relative risk [RR], 0.91; 95% CI, 0.91-0.92), primarily owing to fewer hospitalizations for acute conditions (eg, pneumonia). Medicare Advantage patients had a higher risk of ED direct discharges (RR, 1.30; 95% CI, 1.29-1.31) and observation stays (RR, 2.18; 95% CI, 2.15-2.21) for ACSCs vs traditional Medicare patients. Overall, Medicare Advantage patients were at higher risk of needing care for an ACSC (hospitalization, ED direct discharge, or observation stay) than traditional Medicare patients (RR, 1.20; 95% CI, 1.19-1.20). Within the Medicare Advantage population, patients in health maintenance organizations (HMOs) were at lower risk of ACSC-related hospitalization compared with patients in its preferred provider organizations (RR, 0.95; 95% CI, 0.94-0.97); however, those in the HMOs had a higher risk of ED direct discharge (RR, 1.08; 95% CI, 1.06-1.09) and observation stay (overall RR, 1.10; 95% CI, 1.07-1.13).

Conclusions and Relevance

The findings of this cross-sectional study of Medicare Advantage and traditional Medicare patients with ACSCs indicate that apparent gains in lowering rates of potentially avoidable acute care have been associated with shifting inpatient care to settings such as ED direct discharges and observation stays.
Assessment of Alcohol Exposure From Alcohol-Based Disinfectants Among Premature Infants in Neonatal Incubators in Japan
Authors: Hitaka Daisuke , Fujiyama Satoshi , Nishihama Yukiko , Ishii Ryota , Hoshino Yusuke , Hamada Hiromi , Miyazono Yayoi , Nakayama Shoji F. , Takada Hidetoshi
Published: February 2023

Importance

The risk of premature infants in neonatal incubators exposed to evaporated alcohol from alcohol-based disinfectants (ABDs) is unknown.

Objective

To assess alcohol concentrations in the peripheral blood of premature infants and neonatal incubators.

Design, Setting, and Participants

A quality improvement study comparing 2 different populations before and after introduction of ABD practice (ABD-PRAC) was conducted in a neonatal intensive care unit of a single tertiary hospital in Japan. Participants included premature infants who were born before 34 weeks of gestational age and received medical care in neonatal incubators. The study consisted of 3 periods: (1) September 1, 2020, to August 1, 2021 (prospective observation of pre–ABD-PRAC, (2) August 2 to August 22, 2021 (introduction of ABD-PRAC to medical staff and parents in the neonatal intensive care unit), and (3) August 23, 2021, to March 31, 2022 (prospective observation of post–ABD-PRAC). No follow-up studies were initiated.

Interventions

An ABD-PRAC that aimed to reduce alcohol evaporation from ABDs inside neonatal incubators was instituted: (1) place alcohol preps in the incubator just before use and remove them from the incubator as soon as possible and (2) withhold placing hands into the incubators until 60 seconds after using ABDs for disinfection (applied only to family members).

Main Outcomes and Measures

Blood alcohol concentration and evaporated alcohol concentrations in neonatal incubators.

Results

Disinfectant practice was assessed among 28 infants during the pre–ABD-PRAC (17 infants [10 girls]; median gestational age at birth, 29.4 [IQR, 26.3-30.3] weeks) and post–ABD-PRAC (11 infants [3 girls]; median gestational age at birth, 30.0 [IQR, 25.3-32.2] weeks) study periods. The median blood alcohol concentration was 7.0 (IQR, 5.4-9.3) mg/dL pre–ABD-PRAC and 4.2 (IQR, 2.5-7.2) mg/dL post–ABD-PRAC. The median evaporated alcohol concentration inside neonatal incubators during pre–ABD-PRAC during the day was 23.6 (IQR, 15.9-36.5) ppm and, at night, was 13.2 (IQR, 8.9-19.4) ppm; during post–ABD-PRAC, the concentration was 9.4 (IQR, 6.0-16.0) ppm during the day and 5.7 (IQR, 3.6-9.7) ppm at night. The introduction of ABD-PRAC at 22 weeks’ corrected gestational age was associated with a lower blood alcohol concentration in premature infants: regression coefficient value, −8.3 (95% CI, −12.0 to −4.7).

Conclusions and Relevance

In this study, alcohol evaporated from ABDs was absorbed by premature infants in neonatal incubators. The findings suggest that introduction of ABD-PRAC was associated with lower alcohol concentrations in neonatal incubators and in the blood of premature infants.
Photoacoustic imaging of hidden dental caries using visible–light diode laser
Authors: Tasmara Fikhri Astina , Widyaningrum Rini , Setiawan Andreas , Mitrayana Mitrayana
Published: February 2023

Background

Hidden caries is a type of tooth decay that is difficult to identify through visual diagnosis because teeth with hidden caries appear normal on the tooth surface but are damaged underneath.

Methods

A photoacoustic imaging system based on visible light using a diode laser with a wavelength of 532 nm was developed to detect hidden caries in teeth.

Results

The results indicate that the average of acoustic intensity level for healthy teeth is −74.2 ± 0.1 dB, and the average of acoustic intensity range for teeth with hidden caries is −81.2 ± 0.5 dB. The intensity level for the caries area varies depending on the severity of caries.

Conclusion

Based on the acoustic intensity level measured by the interaction of teeth with laser light, the photoacoustic imaging system in the study can accurately detect the presence of hidden caries and recognize the difference between caries teeth and healthy teeth. This research can be developed into a prototype of a simple device that makes it easy to operate in dental practice.
Wind turbine emulator control improvement using nonlinear PI controller for wind energy conversion system: Design and real‐time implementation
Authors: Hazzab Abdeldjebar , Gouabi Hicham , Habbab Mohamed , Rezkallah Miloud , Ibrahim Hussein , Chandra Ambrish
Published: February 2023

Wind turbine emulators (WTE) have become a necessity for testing, developing, and improving design and control strategies in the renewable energy domain. The aim of this paper is to realize an experimental standalone wind energy conversion system emulator (WECSE) with improved torque and current control strategy using a nonlinear PI controller. The prototype was developed with a separately excited DC motor to simulate the wind turbine by providing the required speed and torque for power generation using a directly driven wound‐rotor synchronous generator and a power conversion system controlled by a modified drift‐free Perturb and Observe (P&O) Maximum Power Point Tracking algorithm (MPPT). The DC motor torque is controlled by an nonlinear PI controller regulator for an estimated current reference through a chopper driven by a dSPACE control board where the MATLAB/Simulink platform is used for wind turbine simulation. The proposed method was validated by experimental tests for different wind speeds and was compared with the conventional method. The experimental results have demonstrated that the control, emulation, and MPPT performances of the proposed method are significantly better.
Finite‐time adaptive quantized control of stochastic nonstrict‐feedback constrained nonlinear systems with multiple unmodeled dynamics
Authors: Chen Penghao , Luan Xiaoli , Liu Fei
Published: February 2023

In this article, a finite‐time adaptive quantized dynamic surface control problem is solved for stochastic partially nonaffine nonstrict‐feedback constrained nonlinear systems with multiple unmodeled dynamics. Firstly, a variable energy function is built to handle the stochastic state unmodeled dynamics under nonstrict‐feedback structure, and a normalized signal is employed to process the input unmodeled dynamics. Furthermore, a specific transformation technique is introduced to keep all states in a predefined asymmetric dynamic constrained region. Compared with the existing results, it not only avoids the circular argument, and also relaxes the condition of the constraint function. Then, the nonlinear function is approximated with the linearly parameterized neural networks. Subsequently, in order to make the tracking error reach a steady state in the finite time, with the help of the properties of the Gaussian function and dynamic surface control technique, a novel finite‐time adaptive quantized controller is designed to ensure that all error signals are semi‐globally practical finite‐time stable and all states obey stochastic probabilistic constraints. Numerical simulation examples are provided to verify the theoretical results obtained.
Strong Electronic Interaction between Amorphous MnO2 Nanosheets and Ultrafine Pd Nanoparticles toward Enhanced Oxygen Reduction and Ethylene Glycol Oxidation Reactions
Authors: Wang Ying , Liu Jiali , Yuan Hongjie , Liu Fan , Hu Tianjun , Yang Benqun
Published: February 2023

Strengthening the interface interaction between metal and support is an efficient strategy to improve the intrinsic activity and reduce the amount of noble metal. Amorphization of support is an effective approach for enhancing the metal‐support interaction due to the numerous surface defects in amorphous structure. In this work, a Pd/a‐MnO2 electrocatalyst containing ultrafine and well‐dispersive Pd nanoparticles and amorphous MnO2 nanosheets is successfully synthesized via a simple and rapid wet chemical method. Differing from the crystal counterpart (Pd/c‐MnO2), the flexible structure of amorphous support can be more favorable to electron transfer and further enhance the metal‐support interaction. The synergism between Pd and amorphous MnO2 results in the downshift of the d‐band center, which is beneficial for the desorption of critical intermediates both in oxygen reduction reaction (ORR) and in ethylene glycol oxidation (EGOR). Due to the lower *.OH desorption energy of Pd/a‐MnO2 surface, the rapid dissociation of *OH from Pd facilitates the formation of H2O in ORR, thus demonstrating superior ORR performance comparable to Pt/C. For EGOR, the presence of amorphous MnO2 promotes the formation of adsorbed OH species, which accelerates the desorption of intermediate CO from Pd sites, and thus exhibits excellent EGOR activity and stability.
3D Polydentate Complexing Agents for Passivating Defects and Modulating Crystallinity for High‐Performance Perovskite Solar Cells
Authors: Liu Congcong , Su Haijun , Pu Yu , Guo Min , Zhai Peng , Liu Lin , Fu Hengzhi
Published: February 2023

The grain boundaries (GBs)/surface defects within perovskite film directly impede the further improvement of photoelectric conversion efficiency (PCE) and stability of planar perovskite solar cells (PSCs). Herein, 3D phytic acid (PA) and phytic acid dipotassium (PAD) with polydentate are explored to synchronously passivate the defects of perovskite absorber directly in multiple spatial directions. The strong electron‐donating groups (H2PO4) in the PA molecule afford six anchor sites to bind firmly with uncoordinated Pb2+ at the GBs/surface and modulate perovskite crystallization, thus enhancing the quality of perovskite film. Particularly, PAD containing an additional (K→PO) push–pull structure promotes the dominant coordination of phosphate group (PO) with Pb2+ and passivates halide anion defects due to the complexation of potassium ions (K+) with iodide ions (I‐). Consequently, the PAD‐complexed PSCs deliver a champion PCE of 23.18%, which is remarkably higher than that of the control device (19.94%). Meanwhile, PAD‐complexed PSCs exhibit superior moisture and thermal stability, remaining 79% of their initial PCE after 1000 h under continuous illumination, while the control device remain only 48% of their PCE after 1000 h. This work provides important insights into designing multifunctional 3D passivators for the purpose of simultaneously enhancing the efficiency and stability of devices.
Glyphosate Adsorption from Water Using Hierarchically Porous Metal–Organic Frameworks
Authors: Naghdi Shaghayegh , Brown Emily , Zendehbad Mohammad , Duong Ann , Ipsmiller Wolfgang , Biswas Santu , Toroker Maytal Caspary , Kazemian Hossein , Eder Dominik
Published: February 2023

The selective removal of one ligand in mixed‐ligand MOFs upon thermolysis provides a powerful strategy to introduce additional mesopores without affecting the overall MOF structure. By varying the initial ligand ratio, MOFs of the MIL‐125‐Ti family with two distinct hierarchical pore architectures are synthesized, resembling either large cavities or branching fractures. The performance of the resulting hierarchically porous MOFs is evaluated toward the adsorptive removal of glyphosate (N‐(phosphonomethyl)glycine) from water, and the adsorption kinetics and mechanism are examined. Due to their strong affinity for phosphoric groups, the numerous Ti–OH groups resulting from the selective ligand removal act as natural anchor points for effective glyphosate uptake. The relationships between contact duration, glyphosate concentration, and adsorbent dosage are investigated, and the impact of these parameters on the effectiveness of glyphosate removal from contaminated water samples is examined. The introduction of additional mesopores has increased the adsorption capacities by nearly 3 times with record values exceeding 440.9 mg g−1, which ranks these MOFs among the best‐reported adsorbents.
Plasma Enhanced Lithium Coupled with Cobalt Fibers Arrays for Advanced Energy Storage
Authors: Qiu Zhong , Shen Shenghui , Liu Ping , Li Chen , Zhong Yu , Su Han , Xu Xueer , Zhang Yongqi , Cao Feng , Noori Abolhassan , Mousavi Mir F. , Chen Minghua , He Xinping , Xia Xinhui , Xia Yang , Zhang Wenkui , Tu Jiangping
Published: February 2023

Construction of high efficiency and stable Li metal anodes is extremely vital to the breakthrough of Li metal batteries. In this study, for the first time, groundbreaking in situ plasma interphase engineering is reported to construct high‐quality lithium halides‐dominated solid electrolyte interphase layer on Li metal to stabilize & protect the anode. Typically, SF6 plasma‐induced sulfured and fluorinated interphase (SFI) is composed of LiF and Li2S, interwoven with each other to form a consecutive solid electrolyte interphase. Simultaneously, brand‐new vertical Co fibers (diameter: ≈5 µm) scaffold is designed via a facile magnetic‐field‐assisted hydrothermal method to collaborate with plasma‐enhanced Li metal anodes (SFI@Li/Co). The Co fibers scaffold accommodates active Li with mechanical integrity and decreases local current density with good lithiophilicity and low geometric tortuosity, supported by DFT calculations and COMSOL Multiphysics simulation. Consequently, the assembled symmetric cells with SFI@Li/Co anodes exhibit superior stability over 525 h with a small voltage hysteresis (125 mV at 5 mA cm−2) and improved Coulombic efficiency (99.7%), much better than the counterparts. Enhanced electrochemical performance is also demonstrated in full cells with commercial cathodes and SFI@Li/Co anode. The research offers a new route to develop advanced alkali metal anodes for energy storage.
Dual Active Sites Engineering on Sea Urchin‐Like CoNiS Hollow Nanosphere for Stabilizing Oxygen Electrocatalysis via a Template‐Free Vulcanization Strategy
Authors: Liu Jin , Meng Xin , Xie Jiahao , Liu Bin , Tang Bo , Wang Rongyue , Wang Cheng , Gu Peng , Song Yidong , Huo Sichen , Zou Jinlong
Published: February 2023

Manipulating electronic structure and defects is crucial to achieve on‐demand functionalities of bimetallic sulfide catalysts for oxygen reduction/evolution reactions (ORR/OER). Here, via a vulcanization strategy, defects‐abundant NiCo2S4 needles obtained from sea urchin‐like NiCo2O4 are anchored on surface of hollow carbon‐sphere (NiCo2S4/HCS). NiCo2S4 nanoneedles (≈7.5 nm) are radially grown on shell of HCS with a cavity (254.5 m2 g−1), and their surface becomes rougher after vulcanization due to anion exchange reaction. As‐marked NiCo2S4/HCS‐3 exhibits better ORR activity (half‐wave potential of 0.89 V) and methanol tolerance than Pt/C (0.86 V). NiCo2S4/HCS‐3 shows a lower OER overpotential (310 mV) than RuO2 and retains 90.9% of initial activity after 9 h. Notably, zinc–air battery with NiCo2S4/HCS‐3 reveals highly‐stable charging/discharging voltages of 2.11/1.16 V with a negligible fading for 200 h. NiCo2S4 grown on outer/inner surfaces of HCS expands spatial distribution of active sites to enhance reactants‐electrode contact and charge transfer. Theoretical calculation shows that Co‐site with an electronic state near Fermi energy level is chiefly‐responsible for ORR, while Ni‐site mainly affords high OER activity. Bader charge analyses reveal that S doping increases the charge density and redox active sites in NiCo2S4. It sheds light on the understanding of electrocatalytic mechanisms on bimetallic sulfides for electronic device.
Interaction Between Prussian Blue Ultrathin Nanosheet and Ammonium Perchlorate for Highly Efficient Thermal Decomposition
Authors: Zhou Peng , Ren Zhuoqun , Tang Xiaolin , Zheng Zeyu , Zhang Kuan , Liao Jun , Zhong Yalan , Zhang Yifu , Huang Chi
Published: February 2023

Catalytic stability is the prerequisite for the catalyst to achieve high catalytic efficiency. This study finds a new path that Prussian Blue (PB) ultrathin nanosheet assembly material (PB‐NSa) is designed and used to reach efficient catalysis through continuous interaction with ammonium perchlorate (AP, component to be catalyzed). Based on the strong oxidation environment provided by AP, the decomposition of PB occurs in advance, the product Fe2O3 accelerates the decomposition of AP that can release a large amount of gas, then reacts on Fe2O3 and disperses it near the undecomposed AP, finally realizing continuous and efficient catalysis. The results show that under the catalysis of PB‐N, “deactivation” stage of AP thermal decomposition disappears, showing two consecutive exothermic stages, high temperature decomposition peak of AP is reduced to 341.1 °C, the reduction range is 73.1 °C. Combining kinetic calculation and TG‐IR test, it is found that PB‐NSa can keep excellent catalytic stability, which depends on its special structure and interaction with AP. This research provides a design idea for the material to achieve catalytic stability, which will greatly promote its rapid industrialization.
Volumetric Printing of Thiol‐Ene Photo‐Cross‐Linkable Poly(ε‐caprolactone): A Tunable Material Platform Serving Biomedical Applications
Authors: Thijssen Quinten , Quaak Astrid , Toombs Joseph , De Vlieghere Elly , Parmentier Laurens , Taylor Hayden , Van Vlierberghe Sandra
Published: February 2023

Current thoroughly described biodegradable and cross‐linkable polymers mainly rely on acrylate cross‐linking. However, despite the swift cross‐linking kinetics of acrylates, the concomitant brittleness of the resulting materials limits their applicability. Here, photo‐cross‐linkable poly(ε‐caprolactone) networks through orthogonal thiol‐ene chemistry are introduced. The step‐growth polymerized networks are tunable, predictable by means of the rubber elasticity theory and it is shown that their mechanical properties are significantly improved over their acrylate cross‐linked counterparts. Tunability is introduced to the materials, by altering Mc (or the molar mass between cross‐links), and its effect on the thermal properties, mechanical strength and degradability of the materials is evaluated. Moreover, excellent volumetric printability is illustrated and the smallest features obtained via volumetric 3D‐printing to date are reported, for thiol‐ene systems. Finally, by means of in vitro and in vivo characterization of 3D‐printed constructs, it is illustrated that the volumetrically 3D‐printed materials are biocompatible. This combination of mechanical stability, tunability, biocompatibility, and rapid fabrication by volumetric 3D‐printing charts a new path toward bedside manufacturing of biodegradable patient‐specific implants.
Intrinsic Anti‐Freezing and Unique Phosphorescence of Glassy Hydrogels with Ultrahigh Stiffness and Toughness at Low Temperatures
Authors: Hou Li Xin , Ju Huaqiang , Hao Xing Peng , Zhang Haoke , Zhang Lei , He Zhiyuan , Wang Jianjun , Zheng Qiang , Wu Zi Liang
Published: February 2023

Most hydrogels become frozen at subzero temperatures, leading to degraded properties and limited applications. Cryoprotectants are massively employed to improve anti‐freezing property of hydrogels; however, there are accompanied disadvantages, such as varied networks, reduced mechanical properties, and the risk of cryoprotectant leakage in aqueous conditions. Reported here is the glassy hydrogel having intrinsic anti‐freezing capacity and excellent optical and mechanical properties at ultra‐low temperatures. Supramolecular hydrogel of poly(acrylamide‐co‐methacrylic acid) with moderate water content (≈50 wt.%) and dense hydrogen‐bond associations is in a glassy state at room temperature. Since hydrogen bonds become strengthened as the temperature decreases, this gel becomes stronger and stiffer, yet still ductile, with Young's modulus of 900 MPa, tensile strength of 30 MPa, and breaking strain of 35% at −45 °C. This gel retains high transparency even in liquid nitrogen. It also exhibits unique phosphorescence due to presence of carbonyl clusters, which is further enhanced at subzero temperatures. Further investigations elucidate that the intrinsic anti‐freezing property is related to a fact that most water molecules are tightly bound and confined in the glassy matrix and become non‐freezable. This correlation, as validated in several systems, provides a roadmap to develop intrinsic anti‐freezing hydrogels for widespread applications at extreme conditions.
Experimental Observation of a Magnetic Interfacial Effect
Authors: Silva Wibson W. G. , Degiorgi Sérgio V. B. , Holanda José
Published: February 2023

A magnetic interfacial effect is observed due to the coupling between two surfaces of different materials. The studied interface is a noncollinear antiferromagnet and a quasi‐ferromagnet. The effect is measured using the ferromagnetic resonance technique without and with electric current and unequivocally proved its existence.
Highly Emissive Chiral Mn(II) Bromide Hybrids for UV‐Pumped Circularly Polarized LEDs and Scintillator Image Applications
Authors: Davydova Maria P. , Meng Lingqiang , Rakhmanova Mariana I. , Bagryanskaya Irina Yu. , Sulyaeva Veronica S. , Meng Hong , Artem'ev Alexander V.
Published: February 2023

Organic–inorganic hybrid metal halides are a promising platform for the design of materials for circularly polarized luminescence (CPL) and X‐ray detection applications. Meanwhile, despite the recent progress in this hot field, hybrid metal halides, simultaneously endowed with efficient CPL and high photoluminescence quantum yield (PLQY), are still limited to a few examples. Herein, the efficient, stable, and low‐cost CPL‐active Mn(II) hybrids are developed via blending of luminogenic [MnBr4]2− anions with N/OH‐bond free R/S‐[MBA‐Me3]+ cations in a single ionic structure. The synthesized R/S‐[MBA‐Me3]MnBr4 hybrids display brightly green Mn2+‐centered circularly polarized phosphorescence with near‐unity PLQY and a high glum factor of 0.0045. Single crystals of R/S‐[MBA‐Me3]MnBr4 are used to fabricate UV‐pumped circularly polarized light‐emitting diodes (LEDs) displaying a high optical selectivity upon exposure to right‐handed and left‐handed circular polarization conditions. Moreover, the titled compounds are found to emit strong X‐ray radioluminescence with excellent linear response to X‐ray dose rate that is used for X‐ray imaging demonstration. These findings reveal a great potential of R/S‐[MBA‐Me3]MnBr4 as low‐cost materials for CPL‐LEDs, scintillators, and X‐ray imaging applications.
Hydrophobic Ni@N‐Doped TiO2 Nanosheet Arrays‐Carbon Paper Photocatalyst for CO2 Photoreduction at Tri‐Phase Interfaces
Authors: Zhao Dawei , Dang Chunzhuo , Xuan Yimin , Zhu Qibin
Published: February 2023

Rational interphase reaction provides a feasible method to overcome the matters of insufficient adsorption of CO2 molecules at the catalytic sites and competitive hydrogen evolution reaction (HER), which can increase the formation rate and selectivity of carbon derivatives in photocatalytic CO2 reduction. Herein, a hydrophobic photocatalyst with TiO2 nanosheet arrays grown on hydrophobic carbon paper (TiO2‐HCP) is fabricated using a combination of magnetron sputtering and hydrothermal method, and its unique structure not only endows it excellent light absorption and effective carrier spatial separation but also avoids the hydrophobic reagent covering reactive sites. When the interphase reaction shifts from solid–liquid diphase to gas‐liquid‐solid tri‐phase, the photocatalytic CO2 reduction over TiO2‐HCP mainly generates CO molecules and effectively suppresses HER due to the HCP suppressing the mass transfer of H2O molecules to active sites. Notably, amounts of H2 byproduct can further react with CO2/CO to produce high value‐added CH4 resultant by modifying the N‐doped TiO2‐HCP with nickel/nickel oxide species. In the tri‐phase interfacial CO2 photoreduction system, the CH4 formation rate of Ni@N‐doped TiO2‐HCP reaches 134.17 µmol m−2 h−1 (about 74.6% selectivity) and total carbon derivatives selectivity is about 93%.
Activation Function Dependence of Data‐Driven Spectra Prediction of Nanostructures
Authors: Qiu Weiyang , He Cheng , Zheng Genrang , Yi Qiaoling , Chen Guo
Published: February 2023

Accompanied by the fast growth of data and computing power, Deep Learning has developed at a tremendous speed. Other related areas including material science, physics, chemistry, medical science, and engineering also benefit from this well‐proven powerful tool. Activation function is an essential part of Deep Neural Networks, which has attracted a lot of attention, but there are few researches based on nanophotonics problems. In this work, comprehensive research is made on the effectiveness of several widely used activation functions. This research shows that among those fancy activation functions that are investigated, Tanhshrink performs the best, which can predict the spectra with a Root Mean Square Error <0.005 for over 99% of these randomly generated instances. Other traditional activation functions like Tanh and Sigmoid also show excellent outcomes in competition with novel ones. This work shows that although deep learning has already been a powerful tool to solve physics problems, there is still a lot of fundamental work to be done to achieve its maximum potential.
High‐Efficiency and Stable Long‐Persistent Luminescence from Undoped Cesium Cadmium Chlorine Crystals Induced by Intrinsic Point Defects
Authors: Yang Ruoting , Yang Dongwen , Wang Meng , Zhang Fei , Ji Xinzhen , Zhang Mengyao , Jia Mochen , Chen Xu , Wu Di , Li Xin Jian , Zhang Yu , Shi Zhifeng , Shan Chongxin
Published: February 2023

Application of long‐persistent luminescence (LPL) materials in many technological fields is in the spotlight. However, the exploration of undoped persistent luminescent materials with high emission efficiency, robust stability, and long persistent duration remains challenging. Here, inorganic cesium cadmium chlorine (CsCdCl3) is developed, featuring remarkable LPL characteristics at room temperature, which is synthesized by a facile hydrothermal method. Excited by ultraviolet light, the CsCdCl3 crystals exhibit an intense yellow emission with a large photoluminescence quantum yield of ≈90%. Different from the reported systems with lanthanides or transition metals doping, the CsCdCl3 crystals without dopants perform yellow LPL with a long duration of 6000 s. Joint experiment‐theory characterizations reveal the intrinsic point defects of CsCdCl3 act as the trap centers of excited electrons and the carrier de‐trapping process from such trap sites to localized emission centers contributes to the LPL. Encouraged by the attractive fluorescence and persistent luminescence as well as good stability of CsCdCl3 against environment oxygen/moisture (75%), heat (100 °C for 10 h), and ultraviolet light irradiation, an effective dual‐mode information storage‐reading application is demonstrated. The results open up a new frontier for exploring LPL materials without dopants and provide an opportunity for advanced information storage compatible for practical applications.
Manageable Bubble Release Through 3D Printed Microcapillary for Highly Efficient Overall Water Splitting
Authors: Zeng Tianbiao , Guo Binbin , Xu Zhiyao , Mo Funian , Chen Xiaoteng , Wang Liping , Ding Yihong , Bai Jiaming
Published: February 2023

Porous metal foams (e.g., Ni/Cu/Ti) are applied as catalyst supports extensively for water splitting due to their large specific area and excellent conductivity, however, intrinsic bubble congestion is unavoidable because of the irregular three‐dimensional (3D) networks, resulting in high polarization and degraded electrocatalytic performances. To boost the H2O decomposition kinetics, the immediate bubble removal and water supply sequential in the gas–liquid–solid interface is essential. Inspired by the high efficiency of water/nutrient transport in the capillaries plants, this work designs a graphene‐based capillary array with side holes as catalyst support to manage the bubble release and water supply via a Z‐axis controllable digital light processing (DLP) 3D printing technology. Like planting rice, a low‐cost, high‐active CoNi carbonate hydroxide (CoNiCH) is planted on support. A homemade cell can reach 10 mA cm−2 in 1.51 V, and be kept at 30 mA cm−2 for 60 h without noticeable degradation, surpassing most of the known cells. This research provides a promising avenue to design and prepare advanced catalysts in various fields, including energy applications, pollutant treatment, and chemical synthesis.
Do Silene species with exposed stigmas tolerate interference by heterospecific pollen?
Authors: Hao Kai , Fang Qiang , Huang Shuang‐Quan
Published: February 2023

Premise

Co‐flowering species that have not evolved an avoidance mechanism may have tolerance to heterospecific pollen (HP) deposition as an adaptive strategy to minimize any deleterious effects of HP transfer, but empirical evidence for the tolerance hypothesis remains scarce.

Methods

To estimate the potential effects of heterospecific pollen deposition (HPD) on female reproductive success, we counted conspecific (CP) and HP pollen grains deposited on stigmas and assessed subsequent seed set of both open‐ and hand‐pollinated flowers in three co‐flowering Silene species with exposed stigmas that usually received numerous HP grains on the elongated receptive area.

Results

The percentage of HP grains per flower (HP%) varied from 16.6% to 43.0% among three species. Silene chungtienensis had lower HP%, and the CP‐HP relationship was neutral; S. gracilicaulis and S. yunnanensis had a relatively higher HP% with a positive CP‐HP relationship. The effects of CP and HP number on natural seed set were positive for all three species, but HP% had stronger negative effects in S. chungtienensis and S. gracilicaulis. In hand‐pollinated flowers of the three Silene species, seed set did not decrease with HP whether CP was in excess or insufficient, indicating no negative effects of HPD on seed production.

Conclusions

Consistent with the tolerance hypothesis, our results indicated that species with higher HP interference are likely to be tolerant to an increase in HP%. These species with generalist‐pollinated flowers and exposed large stigmas may benefit from an increase of conspecific pollen deposition, despite the associated increase in heterospecific pollen deposition.
UV‐Licht trifft Mechanochemie: Die Regioselektive Photochemische Festkörpersynthese von Nanographenen
Authors: Baier Daniel M. , Spula Carolina , Fanenstich Stephen , Grätz Sven , Borchardt Lars
Published: February 2023

Aufgrund der geringen Eindringtiefe von Licht sind photochemische Reaktoren auf hohe Verdünnungen angewiesen, um chemische Reaktionen zu ermöglichen. In diesem Beitrag stellen wir eine neue Methode der UV‐Photochemie in Abwesenheit großer Mengen Lösungsmitteln in einer Kugelmühle vor. Triphenylen wurde mittels der Mallory‐Reaktion und der Cyclodehydrochlorierung (CDHC) in Ausbeuten von 81 bzw. 92 % synthetisiert. Die CDHC wurde erfolgreich in den Gramm‐Maßstab skaliert, und die Robustheit der Methode für verschiedene Substrate nachgewiesen. Schließlich wurde der regioselektive Aufbau von Nanographenen für größere Systeme demonstriert. Der hier vorgestellte mechanochemische Ansatz bietet somit ein vielversprechendes neues Werkzeug zur Konstruktion von Nanographenen.
Electroreduction Enables Regioselective 1,2‐Diarylation of Alkenes with Two Electrophiles
Authors: Yu Weijie , Wang Shengchun , He Meng , Jiang Zhou , Yu Yi , Lan Jinping , Luo Jin , Wang Pengjie , Qi Xiaotian , Wang Tao , Lei Aiwen
Published: February 2023

Precisely introducing two similar functional groups into bulk chemical alkenes represents a formidable route to complex molecules. Especially, the selective activation of two electrophiles is in crucial demand, yet challenging for cross‐electrophile‐coupling. Herein, we demonstrate a redox‐mediated electrolysis, in which aryl nitriles are both aryl radical precursors and redox‐mediators, enables an intermolecular alkene 1,2‐diarylation with a remarkable regioselectivity, thereby avoiding the involvement of transition‐metal catalysts. This transformation utilizes cyanoarene radical anions for activating various aryl halides (including iodides, bromides, and even chlorides) and affords 1,2‐diarylation adducts in up to 83 % yield and >20 : 1 regioselectivity with more than 80 examples, providing a feasible approach to complex bibenzyl derivatives.
Domino‐meta‐C−H‐Ethylglykosylierung durch Ruthenium(II/III)‐Katalyse: Modularer Aufbau von meta‐C‐Alkylglykosiden
Authors: Wu Jun , Wei Wen , Pöhlmann Julia , Purushothaman Rajeshwaran , Ackermann Lutz
Published: February 2023

Radikalische Glykosyladditionsreaktionen sind gut erforscht und haben sich als eine effiziente Syntheseroute von C‐Alkylglykosiden erwiesen. Jedoch sind mehrkomponentige Domino‐Transformationen, für einen schnellen und kontrollierbaren Aufbau strukturell diversifizierter C‐Alkylglykoside, in einem einzigen Schritt, noch selten. Im Gegensatz dazu berichten wir hier über eine Ruthenium(II)‐katalysierte Domino‐meta‐C−H‐Ethylglykosylierung, welche die Herstellung anspruchsvoller meta‐C‐Alkylglykoside ermöglicht. Unsere Ruthenium(II)‐Katalyse zeichnete sich durch milde Reaktionsbedingungen, ausschließlicher meta‐Selektivität und einer hohen anomeren Selektivität aus. Darüber hinaus ermöglichte die Ruthenium(II)‐katalysierte Domino‐meta‐C−H‐Glykosylierung die Synthese vielseitiger 1,2‐trans‐C‐Alkylglykoside mit kommerziell erhältlichen Vinylarenen, Acrylaten und leicht zugänglichen Glykosylbromiden.
Dominometa‐C−H Ethyl Glycosylation by Ruthenium(II/III) Catalysis: Modular Assembly ofmeta‐C‐Alkyl Glycosides
Authors: Wu Jun , Wei Wen , Pöhlmann Julia , Purushothaman Rajeshwaran , Ackermann Lutz
Published: February 2023

Glycosyl anomeric radical addition reactions have been well‐explored and proved efficient for theC‐alkyl glycosides synthesis, but multicomponent Domino transformations for the rapid and controllable construction of structurally diversifiedC‐alkyl glycosides in a single step are still rare. In contrast, we, herein, report a ruthenium(II)‐catalyzed Dominometa‐C−H ethyl glycosylation, enabling the construction of challengingmeta‐C‐alkyl glycosides. Our ruthenium(II) catalysis was reflected by the mild reaction condition, exclusivemeta‐site selectivity and high levels of anomeric selectivity. In addition, the ruthenium(II)‐catalyzed Dominometa‐C−H glycosylation allowed for the synthesis of versatile 1,2‐trans‐C‐alkyl glycosides with commercially available vinyl arenes, acrylates and easily accessible glycosyl bromides.
Silicon rubber grafted with hydrophilic and thermoresponsive poly(DEGMA‐co‐OEGMA) with improved hemo‐ and cyto‐compatibility
Authors: Montoya‐Villegas Kathleen Abigail , González‐Ayón Mirian Angelene , Alvarez‐Lorenzo Carmen , Licea‐Claveríe Angel , Bucio Emilio , Ramírez‐Jiménez Alejandro
Published: February 2023

The grafting of thermo‐responsive, hydrophilic, hemo‐ and biocompatible poly(DEGMA‐co‐OEGMA) onto silicone rubber was carried out by the gamma‐radiation pre‐irradiation method. The size of the grafted chains was controlled using 4‐cyano‐4‐(propylsulfanylthiocarbonyl)sulfanyl pentanoic acid as RAFT agent. Different graft parameters were evaluated to obtain an adequate grafting percentage which allows combining the features of both the matrix and the grafted polymers. The controlled process was confirmed by GPC analysis of the homopolymers formed during the grafting process as by‐products and their molar composition was determined by 1H‐NMR. Grafted materials were characterized by FTIR‐ATR, differential scanning calorimetry, thermogravimetric analysis, dynamic mechanical analysis, scanning electron microscopy, and optical profilometry, while hydrophilicity and temperature‐responsive behavior were evaluated by water absorbing capacity and contact angle measurements. The obtained materials showed enhanced hydrophilicity and excellent hemo‐ and cytocompatibility as evaluated in terms of hemolysis, thrombus formation, protein adsorption, cell viability, and cytotoxicity. The obtained materials showed potential to be applied in the biomedical field in devices in contact with blood.
Ecomorphological correlates of inner and middle ear anatomy within phyllostomid bats
Authors: Dickinson Edwin , Tomblin Emily , Rose Madison , Tate Zoe , Gottimukkula Mihika , Granatosky Michael C. , Santana Sharlene E. , Hartstone‐Rose Adam
Published: February 2023

Echolocation is the primary sense used by most bats to navigate their environment. However, the influence of echolocating behaviors upon the morphology of the auditory apparatus remains largely uninvestigated. While it is known that middle ear ossicle size scales positively with body mass across mammals, and that peak call frequency scales negatively with body mass among bats, there are still large gaps in our understanding of the degree to which allometry or ecology influences the morphology of the chiropteran auditory apparatus. To investigate this, we used μCT datasets to quantify three morphological components of the inner and middle ear: ossicle size, ossicle shape, and cochlear spirality. These data were collected across 27 phyllostomid species, spanning a broad range of body sizes, habitats, and dietary categories, and the relationships between these variables and ear morphology were assessed using a comparative phylogenetic approach. Ossicle size consistently scaled with strong negative allometry relative to body mass. Cochlear spirality was significantly (p = .025) associated with wing aspect ratio (a proxy for habitat use) but was not associated with body mass. From a morphological perspective, the malleus and incus exhibited some variation in kind with diet and call frequency, while stapes morphology is more closely tied to body size. Future work will assess these relationships within other chiropteran lineages, and investigate potential morphological differences in the middle and inner ear of echolocating‐vs‐non‐echolocating taxa.
Metal‐Ion/Metal Nanoparticle‐Anchored Porous Organic Polymers as Efficient Catalysts for Organic Transformations – A Recent Overview
Authors: Kathiresan Murugavel
Published: February 2023

Porous organic polymers are porous materials that are interlinked with organic building blocks by strong covalent bonds. The functional groups on the building blocks can be carefully chosen to obtain a POP with desired functionalities. In certain cases, the pores or voids interact with the organic molecules via non‐covalent interactions and hence they serve as catalytic centers. In many cases, pristine POPs themselves were evaluated as heterogeneous catalysts for their catalytic activity. The inner functional groups of POPs act as a ligand or interact with metal ions/metal nanoparticles and hence a wide range of metal‐ion‐anchored POPs or metal nanoparticle‐loaded POPs were reported. These metal‐ion‐anchored POPs can catalyze different organic reactions as that of pristine metal‐based catalysis following a heterogeneous pathway. In this type of catalysis, POP plays an important role, i. e., it serves as a carbon matrix, and interacts with organic molecules via non‐covalent interactions, further in metal/metal‐ion‐anchored POPs, the metal concentration is highly reduced and the organic transformation effectively takes place at the interface of metal/carbon matrix. Herein, we discuss the recent developments on metal‐ion/metal nanoparticle loaded POPs and their role in various organic transformations such as C−C coupling reactions, borrowing hydrogen reactions, CO2 transformations, hydroformylations reactions, oxidation of alkynes to 1,2‐diketones and C−H arylation reactions.