Effects of Liquid Viscosity on the Formation and Attenuation of Capillary Waves Induced by AC Electrowetting-on-Dielectric.

The capillary waves induced by electrowetting-on-dielectric have great potential in terms of capillary propulsion and other applications. At present, these applications are limited by a lack of research on the effects of liquid viscosity, which is an important parameter in controlling this phenomenon. This paper examines the formation, propagation, and attenuation of electrowetting-on-dielectric-induced capillary waves (EWCWs) on a liquid-free surface with different levels of liquid viscosity. The formation and propagation of the capillary waves are visualized using a high-speed camera and a free-surface synthetic Schlieren method. A theoretical model is established to describe the wave amplitude and wave propagation of EWCWs. The results show that the liquid viscosity, as well as the surface tension, significantly affects the formation and propagation of EWCWs. Using the results presented in this paper, a new type of Stokes viscometer based on EWCWs is proposed, enabling accurate measurements of liquid viscosity over a wide range of viscosity and temperature conditions.

Evolution of Cherries (Prunus Subgenus Cerasus) Based on Chloroplast Genomes.

Cherries (Prunus Subgenus Cerasus) have economic value and ecological significance, yet their phylogeny, geographic origin, timing, and dispersal patterns remain challenging to understand. To fill this gap, we conducted a comprehensive analysis of the complete chloroplast genomes of 54 subg. Cerasus individuals, along with 36 additional genomes from the NCBI database, resulting in a total of 90 genomes for comparative analysis. The chloroplast genomes of subg. Cerasus exhibited varying sizes and consisted of 129 genes, including protein-coding, transfer RNA, and ribosomIal RNA genes. Genomic variation was investigated through InDels and SNPs, showcasing distribution patterns and impact levels. A comparative analysis of chloroplast genome boundaries highlighted variations in inverted repeat (IR) regions among Cerasus and other Prunus species. Phylogeny based on whole-chloroplast genome sequences supported the division of Prunus into three subgenera, I subg. Padus, II subg. Prunus and III subg. Cerasus. The subg. Cerasus was subdivided into seven lineages (IIIa to IIIg), which matched roughly to taxonomic sections. The subg. Padus first diverged 51.42 Mya, followed by the separation of subg. Cerasus from subg. Prunus 39.27 Mya. The subg. Cerasus started diversification at 15.01 Mya, coinciding with geological and climatic changes, including the uplift of the Qinghai-Tibet Plateau and global cooling. The Himalayans were the refuge of cherries, from which a few species reached Europe through westward migration and another species reached North America through northeastward migration. The mainstage of cherry evolution was on the Qing-Tibet Plateau and later East China and Japan as well. These findings strengthen our understanding of the evolution of cherry and provide valuable insights into the conservation and sustainable utilization of cherry's genetic resources.

Genetic Analysis and Construction of a Fingerprint for Licensed Triadica sebifera Cultivars Using SSR Markers.

Triadica sebifera is an important landscaping tree species because of its colorful autumn leaves. In recent years, some cultivars have been bred and licensed, but it can be difficult to identify them from their morphological traits due to their similar phenotypes. To explore the genetic relationships and construct a fingerprint of the cultivars, the licensed T. sebifera cultivars were analyzed using SSR markers. A total of 179 alleles were identified among the 21 cultivars at 16 SSR loci, and these alleles exhibited a high level of genetic diversity (He = 0.86). The genetic variations mainly occurred among cultivars based on an analysis of molecular variance (AMOVA). According to phylogenetic analysis, principal coordinate analysis (PCoA), and Bayesian clustering analysis, the genetic relationships were independent of geographic distances, which may be mainly due to transplantations between regions. Some cultivars with different leaf colors showed obvious genetic differentiation and may be preliminary candidates for cross-breeding. Finally, the fingerprint for the licensed cultivars was constructed with two SSR markers. The results of this study can provide technical support for the application and legal protection of licensed Triadica sebifera cultivars.

Orbital Electrowetting-on-Dielectric for Droplet Manipulation on Superhydrophobic Surfaces.

Electrowetting-on-dielectric (EWOD), recognized as the most successful electrical droplet actuation method, is essential in diverse applications, ranging from thermal management to microfluidics and water harvesting. Despite significant advances, it remains challenging to achieve repeatability, high speed, and simple circuitry in EWOD-based droplet manipulation on superhydrophobic surfaces. Moreover, its efficient operation typically requires electrode arrays and sophisticated circuit control. Here, a newly observed droplet manipulation phenomenon on superhydrophobic surfaces with orbital EWOD (OEW) is reported. Due to the asymmetric electrowetting force generated on the orbit, flexible and versatile droplet manipulation is facilitated with OEW. It is demonstrated that OEW droplet manipulation on superhydrophobic surfaces exhibits higher speed (up to 5 times faster), enhanced functionality (antigravity), and manipulation of diverse liquids (acid, base, salt, organic, e.g., methyl blue, artificial blood) without contamination, and good durability after 1000 tests. It is envisioned that this robust droplet manipulation strategy using OEW will provide a valuable platform for various processes involving droplets, spanning from microfluidic devices to controllable chemical reactions. The previously unreported droplet manipulation phenomenon and control strategy shown here can potentially upgrade EWOD-based microfluidics, antifogging, anti-icing, dust removal, and beyond.

Food-borne botulism from homemade sauce leading to cardiac arrest: A family case series with literature review.

Food-borne botulism is a rare but potentially fatal illness. Its management depends on rapid diagnosis and prompt antitoxin administration. However, diagnosing food-borne botulism can be challenging at an early stage. Here, we report a 62-year-old male with food-borne botulism. The patient presented with extremity muscle weakness, dyspnea, bilateral droopy eyelids (more significant on the right side), dysarthria, and progressive dysphagia. The electromyography indicated presynaptic membrane abnormalities. The toxicology screen reported a positive result for botulinum toxin type A. He received plasma exchange, botulism antitoxin, and supportive care. However, he had a cardiac arrest six days later. Spontaneous circulation was restored after immediate cardiopulmonary resuscitation. The patient gradually recovered his muscle strength and could have complete eyelid elevation. A detailed interview revealed that six family members developed similar symptoms. All of them consumed a homemade sauce prepared three years ago. They all tested positive for botulinum toxin type A. Two of them had cardiac arrests. Therefore, family aggregation could happen to botulism. Careful interviews, early diagnosis, and timely administration of botulism antitoxin are the keys to saving lives. Special attentions should be given to the cardiac evaluations since botulism can cause cardiac arrest and death.

Chromosome-Level Assembly of Flowering Cherry (Prunus campanulata) Provides Insight into Anthocyanin Accumulation.

The flowering cherries (genus Prunus, subgenus Cerasus) are popular ornamental trees in China, Japan, Korea, and elsewhere. Prunus campanulata Maxim. is an important species of flowering cherry native to Southern China, which is also distributed in Taiwan, the Ryukyu Islands of Japan, and Vietnam. It produces bell-shaped flowers with colors ranging from bright pink to crimson during the Chinese Spring Festival from January to March each year. We selected the P. campanulata cultivar "Lianmeiren", with only 0.54% of heterozygosity, as the focus of this study, and generated a high-quality chromosome-scale genome assembly of P. campanulata by combining Pacific Biosciences (PacBio) single-molecule sequencing, 10× Genomics sequencing, and high-throughput chromosome conformation capture (Hi-C) technology. We first assembled a 300.48 Mb genome assembly with a contig N50 length of 2.02 Mb. In total, 28,319 protein-coding genes were predicted from the genome, 95.8% of which were functionally annotated. Phylogenetic analyses indicated that P. campanulata diverged from a common ancestor of cherry approximately 15.1 million years ago. Comparative genomic analyses showed that the expanded gene families were significantly involved in ribosome biogenesis, diterpenoid biosynthesis, flavonoid biosynthesis, and circadian rhythm. Furthermore, we identified 171 MYB genes from the P. campanulata genome. Based on the RNA-seq of five organs at three flowering stages, expression analyses revealed that the majority of the MYB genes exhibited tissue-specific expression patterns, and some genes were identified as being associated with anthocyanin accumulation. This reference sequence is an important resource for further studies of floral morphology and phenology, and comparative genomics of the subgenera Cerasus and Prunus.

The complete chloroplast genome of Prunus takasagomontana, a deciduous flowering cherry native to Taiwan island.

Prunus takasagomontana Sasaki 1931 is a deciduous flowering cherry endemic to Taiwan island, China. Here, we first report the complete chloroplast genome of P. takasagomontana. The complete chloroplast genome of P. takasagomontana is 157,946 bp in length, which is comprised of a pair of inverted repeat (IR) regions of 26,437 bp, a small single-copy (SSC) region of 19,145 bp, and a large single-copy (LSC) region of 85,927 bp. A total of 129 genes are annotated, including 84 protein-coding genes, 37 tRNA genes, and eight rRNA ribosomal genes. The phylogenetic analysis showed that P. takasagomontana is sister to P. serrulata var. spontanea.

A Study on the Effects of Selenization Temperature on the Properties of Na-Doped Cu2ZnSn(S,Se)4 Thin Film and Its Correlation with the Performance of Solar Cells.

In this study, we prepared Na-doped Cu2ZnSn(S,Se)4 [noted as (Na0.1Cu0.9)2ZnSn(S,Se)4] films on the Mo substrate using a simple and cheap sol-gel method together with the post-annealing technique. The effects of selenization temperature on the properties of Na-doped Cu2ZnSn(S,Se)4 were surveyed. The results indicated that some sulfur atoms in the films were substituted by selenium atoms by increasing the selenization temperature, and all films selenized at different temperatures had a kesterite structure. As the selenization temperature increased from 520 to 560 °C, the band gaps of the film can be tuned from 1.03 to 1 eV. The film with better morphology and opto-electrical properties can be obtained at an intermediate selenization temperature range (e.g., 540 °C), which had the lowest resistivity of 47.7 Ω cm, Hall mobility of 4.63 × 10-1 cm2/Vs, and carrier concentration of 2.93 × 1017 cm-3. Finally, the best power conversion efficiency (PCE) of 4.82% was achieved with an open circuit voltage (Voc) of 338 mV, a short circuit current density (Jsc) of 27.16 mA/cm2 and a fill factor (FF) of 52.59% when the selenization temperature was 540 °C.

Triboelectric Nanogenerator Powered Electrowetting-on-Dielectric Actuator for Concealed Aquatic Microbots.

Aquatic microbots have drawn great research interest due to the demands in aquatic environmental monitoring, inspection, and confined space exploration. Current actuation methods heavily rely on mechanical motion powered by large-amplitude and high-frequency sources, which limit the applications with portability and concealment requirements. Herein we propose a triboelectric nanogenerator (TENG)-enabled electrowetting-on-dielectric (EWOD) actuator (TENG-EWA) for aquatic microbots. The transferred tribo-charges of a disc TENG alternatively modify the surface energy of the EWOD actuator, yielding a capillary wave propagation. The reaction force of the capillary wave actuates the microbot on the water surface. The characteristics of the TENG induced capillary wave are analyzed experimentally and modeled theoretically. An optical transparent microbot (weight of 0.07 g, body length of 1 cm) was actuated forward at a maximum locomotion velocity of 1 cm/s. Diverse locomotion functions are demonstrated: with a load of 3 times to the robot net weight, in seawater, at a silicone-oil/deionized water interface. Besides, the locomotion of the microbot was demonstrated by a wind-driven TENG, and a good concealment performance was achieved under infrared camera and decibel meter. The proposed aquatic TENG-Bot not only shows the potential of converting environmental energy into actuation force for microbots but also reveals advantages in optical, sonic, and infrared concealment.

Complete chloroplast genome sequence of Prunus mahaleb.

Prunus mahaleb (L.) Mill. is a kind of ornamental species which originated from Europe and Western Asia. Here, we use Illumina paired-end sequencing to obtain the complete chloroplast genome of P. mahaleb. The complete cp genome of P. mahaleb with a size of 157,824 bp in length is a circular molecular genome, including a pair of inverted repeat (IR) region of 26,410 bp each, separated by a large single copy (LSC) region of 85,926 bp and a small single-copy (SSC) region of 19,078 bp. The genome consisted of 129 genes, including 84 protein-codon genes (PCGs), 37 tRNA genes, and eight rRNA genes. The GC content of the whole chloroplast genome is 36.7%. Phylogenetic analysis revealed that P. mahaleb was the closest related to P. cerasoides and P. maximowiczii.

The complete chloroplast genome of Prunus verecunda, and phylogenetic analysis with amygdaleae species.

We assembled complete chloroplast (cp) genome of Prunus verecunda based on Illumina sequencing. The cp genome of P. verecunda is 157,917 bp in length with 129 genes comprising 84 protein-coding genes, 37 tRNA genes and 8 rRNA ribosomal genes. The overall GC content of cp genome is 36.7%. A maximum likelihood phylogenetic analysis revealed that P. verecunda is sister to P. serrulata var. spontanea and P. maximowiczii.

The complete chloroplast genome of Prunus apetala, a native deciduous flowering cherry of Japan.

The complete chloroplast (cp) genome of Prunus apetala was determined. The length of the cp genome of P. apetala is 157,987 bp. A total of 129 genes are comprised of 84 protein-coding genes, 37 tRNA genes, and 8 rRNA ribosomal genes. The overall GC content of cp genome is 36.7%. The phylogenetic position of P. apetala is sister to Prunus serrulata var. spontanea.

Investigation on the Selenization Treatment of Kesterite Cu2Mg0.2Zn0.8Sn(S,Se)4 Films for Solar Cell.

High-selenium Cu2Mg0.2Zn0.8Sn(S,Se)4 (CMZTSSe) films were prepared on a soda lime glass substrate using the sol-gel spin coating method, followed by selenization treatment. In this work, we investigated the effects of selenization temperature and selenization time on the crystal quality, and electrical and optical properties of CMZTSSe films. The study on the micro-structure by XRD, Raman, X-ray photoelectron spectroscopy (XPS), and energy-dispersive X-ray spectroscopy (EDS) analysis showed that all CMZTSSe samples had kesterite crystalline structure. In addition, the crystalline quality of CMZTSSe is improved and larger Se takes the site of S in CMZTSSe with the increase of selenization temperature and selenization time. When increasing the selenization temperature from 500 to 530 °C and increasing the annealing time from 10 to 15 min, the morphological studies showed that the microstructures of the films were dense and void-free. When further increasing the temperature and time, the crystalline quality of the films began to deteriorate. In addition, the bandgaps of CMZTSSe are tuned from 1.06 to 0.93 eV through adjusting the selenization conditions. When CMZTSSe samples are annealed at 530 °C for 15 min under Se atmosphere, the crystal quality and optical-electrical characteristics of CMZTSSe will be optimal, and the grain size and carrier concentration reach maximums of 1.5-2.5 µm and 6.47 × 1018 cm-3.

Investigation of Optimum Mg Doping Content and Annealing Parameters of Cu2MgxZn1-xSnS4 Thin Films for Solar Cells.

Cu2MgxZn1-xSnS4 (0 ≤ x ≤0.6) thin films were prepared by a simple, low-temperature (300 °C) and low-cost sol-gel spin coating method followed by post-annealing at optimum conditions. We optimized the annealing conditions and investigated the effect of Mg content on the crystalline quality, electrical and optical performances of the Cu2MgxZn1-xSnS4 thin films. It was found that the Cu2MgxZn1-xSnS4 film annealed at 580 °C for 60 min contained large grain, less grain boundaries and high carrier concentration. Pure phase kesterite Cu2MgxZn1-xSnS4 (0 ≤ x ≤ 0.6) thin films were obtained by using optimal annealing conditions; notably, the smaller Zn2+ ions in the Cu2ZnSnS4 lattice were replaced by larger Mg2+ ions. With an increase in x from 0 to 0.6, the band gap energy of the films decreased from 1.43 to 1.29 eV. When the ratio of Mg/Mg + Zn is 0.2 (x = 0.2), the grain size of Cu2MgxZn1-xSnS4 reaches a maximum value of 1.5 µm and the surface morphology is smooth and dense. Simultaneously, the electrical performance of Cu2MgxZn1-xSnS4 thin film is optimized at x = 0.2, the carrier concentration reaches a maximum value of 3.29 × 1018 cm-3.

Electrowetting-driven solar indoor lighting (e-SIL): an optofluidic approach towards sustainable buildings.

Optofluidics is an emerging research field that combines the two disciplines of microfluidics and optics. By using microfluidic technologies for light control, optofluidic devices can offer several advantages over solid-type optical components, including optical-grade smoothness at the fluidic interface and a high degree of optical tunability without bulky and complex mechanical moving parts. These features have made optofluidic devices more versatile and reconfigurable to improve their optical performances. In this paper, we present a novel optofluidic sunlight manipulation technology for solar indoor lighting using the electrowetting principle. Rooftop sunlight is collected by a solar concentrator and guided to individual rooms along an optical fiber (waveguide) on the bottom of which tunable liquid prisms are linearly integrated. In the light-off mode, electrowetting controls the apex angle of the prisms to be φ = 0°. Under this condition, incoming sunlight experiences total internal reflection and thus keeps propagating along the optical fiber without leaking to the prism bottom for indoor lighting. In contrast, when liquid prisms are controlled to have the angle at φ > 0°, incoming sunlight is partially transmitted to the bottom surface of the arrayed prisms to contribute to interior illumination. Simulation studies validate that our electrowetting-driven solar indoor lighting (e-SIL) system is capable of variably tuning the lighting power from 0% to 98.6% of the input solar power by controlling the prism angle and varying the refractive index of prism materials. For experimental studies, we fabricated an array of 5 prisms filled with silicone oil and water. Using a fiber illuminator as a white light source that includes visible light with various incident angles, we have demonstrated two important lighting functions, (1) light on/off and (2) illumination power control. Lighting performance can be further enhanced by lowering the aspect ratio of the prism as well as increasing the number of prisms. The e-SIL technology based on tunable liquid prisms offers a new approach towards sustainable buildings that are able to reduce their electricity usage as well as provide a healthy and comfortable indoor environment under illumination of natural sunlight.

The complete chloroplast genome sequence of Styrax zhejiangensis, a species with an extremely small population.

Styrax zhejiangensis is an endemic species to China and is only distributed in Jiande, Zhejiang Province. The species is on the verge of extinction. The chloroplast genome of S. zhejiangensis was determined from Illumina pair-end sequencing data. The sequence was 157,387 bp and consisted of one large (LSC, 87,193 bp) and one small (SSC, 18,286 bp) single-copy region region, separated by a pair of inverted repeat (IR, 25,954 bp) regions. The sequence included 116 genes, including 82 protein-coding genes, 19 rRNAs and 15 tRNAs. The overall GC content was 37.0%. A maximum likelihood phylogenetic analysis showed that Styracaceae was more closely related to Symplocaceae than to Ebenaceae.

Smartphone integrated optoelectrowetting (SiOEW) for on-chip sample processing and microscopic detection of water quality.

With the increasing capabilities and ubiquity of smartphones and their associated digital cameras, this study presents a smartphone integrated optoelectrowetting (SiOEW) device as a simple, portable tool capable of on-chip water sample preparation and microscopic detection of the target cells in water samples, which significantly reduce the detection time and the labor cost required for water quality monitoring. A commercially available smartphone is used as a low-intensity portable light source to perform optoelectrowetting (OEW)-based microfluidic operations such as droplet transportation, merging, mixing, and immobilization on a hydrophobic detection zone. Furthermore, a built-in smartphone camera allows on-chip microscopic detection of water quality with a 45× magnification. We have experimentally demonstrated that the SiOEW platform is able not only to automate the sample processing of marine water including the target algae cells (Amphiprora sp.) and staining reagents fluorescein diacetate (FDA) and 5-chloromethylfluorescein diacetate (CMFDA), but also detect the fluorescence signals emitted from the target cells in water samples and count their populations. Using the smartphone, the collected information (e.g. the location of the water sample collected and the time it was detected, the number of the target cells, etc.) can be rapidly and wirelessly shared with a central host such as an environmental regulation agency for real-time monitoring and further management of water quality.

A droplet energy harvesting and actuation system for self-powered digital microfluidics.

When a water droplet slides down a hydrophobic surface, a major energy it possesses is kinetic energy. However, people may ignore another important energy source: triboelectrification. To quantify and utilize triboelectrification energy, a phenomenon is presented in this study: one droplet slides down a tilted chip with a hydrophobic coating and patterned electrodes, triboelectrification happens and the induced charges are transferred to another horizontally placed chip with copper wires, on which another droplet is actuated by the transferred charges. The mechanism of this phenomenon is triboelectrification, electrostatic induction and EWOD (electrowetting on dielectrics). When an 80 µL droplet slides down the chip, the induced charges build up a potential difference between the electrodes of 46 V. With this potential difference, the droplet actuation is achieved not only on the horizontal chip, but also on the vertical chip. By patterning a comb-shaped electrode, functions for droplet manipulations are achieved. Theoretical analysis is conducted to quantify the frictional force, gravitational force and driving force (EWOD force). The presented concept and device could be employed for a self-powered digital microfluidics (DMF) system, replacing the bulky and energy consuming voltage sources which are commonly used in DMF devices.

Complete chloroplast genome sequences of two endangered Phoebe (Lauraceae) species.

BACKGROUND: Phoebe (Lauraceae) comprises of evergreen trees or shrubs with approximately 100 species, distributed in tropical and subtropical Asia and Neotropical America. A total of 34 species and three varieties occur in China. Despite of economic and ecological value, only limited genomic resources are available for this genus. RESULTS: We sequenced the two complete chloroplast (cp) genomes of Phoebe chekiangensis and P. bournei using Illumina sequencing technology via a combined strategy of de novo and reference-guided assembly. We also performed comparative analyses with the cp genomes of P. sheareri and P. sheareri var. oineiensis previously reported. The chloroplast genomes of P. chekiangensis and P. bournei identically contain 112 genes consisting of 78 protein coding genes, 30 tRNA genes, and 4 rRNA genes, with the size of 152,849 and 152,853 bp, respectively. From the two chloroplast genomes, 131 SSRs were identified and 12 different SSRs located in five protein coding genes. The analysis showed the extremely conserved structure of chloroplast genomes with surprisingly little variations at the LSC/IR and SSC/IR boundaries. Moreover, the mean nucleotide diversity was found to be 0.162% for 77 regions, suggesting an extraordinarily low level of sequence divergence. Four highest divergent regions (trnH-psbA, rps14-trnT, petA-psbJ, ccsA-ndhD) with the percentage of nucleotide diversity higher than 0.50% were identified, which had potential use for species identification and phylogenetic studies. CONCLUSION: This study will facilitate our understanding of population genetics, phylogenetic relationship and plant evolution of Phoebe species.

A Study of Dip-Coatable, High-Capacitance Ion Gel Dielectrics for 3D EWOD Device Fabrication.

We present a dip-coatable, high-capacitance ion gel dielectric for scalable fabrication of three-dimensional (3D) electrowetting-on-dielectric (EWOD) devices such as an n × n liquid prism array. Due to the formation of a nanometer-thick electric double layer (EDL) capacitor, an ion gel dielectric offers two to three orders higher specific capacitance (c ≈ 10 µF/cm²) than that of conventional dielectrics such as SiO2. However, the previous spin-coating method used for gel layer deposition poses several issues for 3D EWOD device fabrication, particularly when assembling multiple modules. Not only does the spin-coating process require multiple repetitions per module, but the ion gel layer also comes in risks of damage or contamination due to handling errors caused during assembly. In addition, it was observed that the chemical formulation previously used for the spin-coating method causes the surface defects on the dip-coated gel layers and thus leads to poor EWOD performance. In this paper, we alternatively propose a dip-coating method with modified gel solutions to obtain defect-free, functional ion gel layers without the issues arising from the spin-coating method for 3D device fabrication. A dip-coating approach offers a single-step coating solution with the benefits of simplicity, scalability, and high throughput for deposition of high-capacitance gel layers on non-planar EWOD devices. An ion gel solution was prepared by combining the [EMIM][TFSI] ionic liquid and the [P(VDF-HFP)] copolymer at various wt % ratios in acetone solvent. Experimental studies were conducted to fully understand the effects of chemical composition ratios in the gel solution and how varying thicknesses of ion gel and Teflon layers affects EWOD performance. The effectiveness and potentiality of dip-coatable gel layers for 3D EWOD devices have been demonstrated through fabricating 5 × 1 arrayed liquid prisms using a single-step dip-coating method. Each prism module has been individually controlled to achieve spatial beam steering without the need for bulky mechanical moving parts.