Publications by authors named "Jicheng Wang"

146 Publications

Comparison of the effects of single probiotic strains Lactobacillus casei Zhang and Bifidobacterium animalis ssp. lactis Probio-M8 and their combination on volatile and nonvolatile metabolomic profiles of yogurt.

J Dairy Sci 2021 Apr 1. Epub 2021 Apr 1.

Key Laboratory of Dairy Biotechnology and Engineering, Ministry of Education, Inner Mongolia Agricultural University, Hohhot 010018, China; Key Laboratory of Dairy Products Processing, Ministry of Agriculture and Rural Affairs, Inner Mongolia Agricultural University, Hohhot 010018, China; Qingdao Special Food Research Institute, Qingdao Agricultural University, Qingdao 266109, China. Electronic address:

There has been a growing interest in cofermentation of starter cultures with probiotics in milk. In this study, we analyzed the effects of adding the single probiotics Lactobacillus casei Zhang (Zhang) or Bifidobacterium animalis ssp. lactis Probio-M8 (M8) or a combination of Zhang and M8 to starter cultures on volatile and nonvolatile metabolomic profiles after 14 d of storage at 4°C and compared using a liquid chromatography-tandem mass spectrometry (LC-MS) and GC-MS-based metabolomics approach. Principal component analysis, heatmap plots, and Spearman correlation results showed that Zhang alone had a greater effect on volatile and nonvolatile metabolomic profiles than M8 alone. The combination of Zhang and M8 had additive effects on the production of metabolites. For volatile metabolites, the levels of acetaldehyde, diacetyl, acetoin, and acetic acid were higher for the combination of Zhang and M8 compared with either single probiotic culture. Significantly increased nonvolatile components induced by adding Zhang were identified were enriched in the galactose, amino- and nucleotide sugar, fructose and mannose, purine, phenylalanine metabolism, and arginine biosynthesis pathways. The metabolism and biosynthesis of starch, sucrose, tyrosine, galactose metabolism, and aminoacyl-tRNA biosynthesis were significantly upregulated by adding the combination of Zhang and M8. This work provides a detailed insight into different effects of Zhang and M8 used alone or in combination on the volatile and nonvolatile metabolomic profiles of yogurts.
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http://dx.doi.org/10.3168/jds.2020-20099DOI Listing
April 2021

Superficial Peroneal Neuromodulation of Persistent Bladder Underactivity Induced by Prolonged Pudendal Afferent Nerve Stimulation in Cats.

Am J Physiol Regul Integr Comp Physiol 2021 Mar 10. Epub 2021 Mar 10.

University of Pittsburgh.

The purpose of this study is to determine if superficial peroneal nerve stimulation (SPNS) can reverse persistent bladder underactivity induced by prolonged pudendal nerve stimulation (PNS). In 16 α-chloralose anesthetized cats, PNS and SPNS were applied by nerve cuff electrodes. Skin surface electrodes were also used for SPNS. Bladder underactivity consisting of a significant increase in bladder capacity to 157.8±10.9% of control and a significant reduction in bladder contraction amplitude to 56.0±5.0% of control was induced by repetitive (4-16 times) application of 30-min PNS. SPNS (1 Hz, 0.2 ms) at 1.5 to 2 times threshold intensity (T) for inducing posterior thigh muscle contractions was applied either continuously (SPNSc) or intermittently (SPNSi) during a cystometrogram (CMG) to determine if the stimulation can reverse the PNS-induced bladder underactivity. SPNSc or SPNSi applied by nerve cuff electrodes during the prolonged PNS inhibition significantly reduced bladder capacity to 124.4±10.7% and 132.4±14.2% of control, respectively, and increased contraction amplitude to 85.3±6.2% and 75.8±4.7%, respectively. Transcutaneous SPNSc and SPNSi also significantly reduced bladder capacity and increased contraction amplitude. Additional PNS applied during the bladder underactivity further increased bladder capacity, while SPNSc applied simultaneously with the PNS reversed the increase in bladder capacity. This study indicates that a non-invasive superficial peroneal neuromodulation therapy might be developed to treat bladder underactivity caused by abnormal pudendal nerve somatic afferent activation that is hypothesized to occur in patients with Fowler's syndrome.
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http://dx.doi.org/10.1152/ajpregu.00346.2020DOI Listing
March 2021

Restoring both continence and micturition after chronic spinal cord injury by pudendal neuromodulation.

Exp Neurol 2021 Feb 24;340:113658. Epub 2021 Feb 24.

Department of Urology, University of Pittsburgh, Pittsburgh, PA, USA; Department of Pharmacology and Chemical Biology, University of Pittsburgh, Pittsburgh, PA, USA; Department of Bioengineering, University of Pittsburgh, Pittsburgh, PA, USA. Electronic address:

Neurogenic bladder management after spinal cord injury (SCI) is very challenging. Daily urethral catheterization is most commonly used to empty the bladder, which causes frequent infections of the lower urinary tract. This study reports a novel idea to restore both continence and micturition after SCI by an implantable pudendal nerve stimulator (PNS). The PNS was surgically implanted in four cats with complete SCI at T9-T10 spinal level and tested weekly for 13-14 weeks under awake conditions. These chronic SCI cats consistently exhibited large residual bladder volumes (average 40-50 ml) due to their inability to void efficiently, while urine leakage also occurred frequently. The PNS which consisted of stimulating the pudendal nerve at 20-30 Hz to trigger a spinal reflex bladder contraction and at the same time blocking the pudendal nerves bilaterally with 10 kHz stimulation to relax the external urethral sphincter and reduce the urethral outlet resistance successfully induced highly efficient (average 80-100%), low pressure (<50 cmHO) voiding. The PNS at 5 Hz also promoted urine storage by inhibiting reflex bladder activity and increasing bladder capacity. At the end of 14-week chronic testing, low pressure efficient voiding induced by PNS was further confirmed under anesthesia by directly measuring voiding pressure using a bladder catheter inserted through the bladder dome. This study demonstrated the efficacy and safety of the PNS in awake chronic SCI cats, suggesting that a novel neuroprosthesis can be developed for humans to restore bladder function after SCI by stimulating and/or blocking the pudendal nerves.
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http://dx.doi.org/10.1016/j.expneurol.2021.113658DOI Listing
February 2021

Characterisation of two unusual cases of haemoglobin Bart's hydrops foetalis caused by - and large novel α-globin gene cluster deletions.

J Int Med Res 2021 Feb;49(2):300060521993642

Medical Genetic Center, Guangdong Women and Children Hospital, Guangzhou, Guangdong, China.

Background: We describe 2 unusual haemoglobin (Hb) Bart's hydrops cases that could not be explained by traditional factors. Two families with a diagnosis or history of foetal hydrops were enrolled. A suspension-array system was used to detect the 23 most frequent mutations in southern China. Multiplex ligation-dependent probe amplification (MLPA) was used to screen for possible deletions. Precise characterisation of the breakpoints of the novel variants and uniparental disomy analysis were performed using a single nucleotide polymorphism (SNP) array. Quantitative fluorescence PCR was used to eliminate maternal cell contamination and nonpaternity. In case 1, the suspension-array system indicated a maternal heterozygous (-/) deletion, and the paternal sample was negative. The foetal hydrops was caused by the maternal (-/) deletion and a de novo α-globin gene deletion (-). In case 2, the paternal sample had a heterozygous (-/) deletion, and MLPA and SNP array analysis revealed a large maternal deletion (-) that encompassed the α-globin gene, which explained the history of Hb Bart's foetal hydrops.

Conclusions: Our cases describe 2 new α-thalassaemia deletions and illustrate the importance of using a combination of methods to detect rare types of α-thalassaemia.
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http://dx.doi.org/10.1177/0300060521993642DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7897832PMC
February 2021

Comparison of cord blood hematological parameters among normal, α-thalassemia, and β-thalassemia fetuses between 17 and 38 weeks of gestation.

Sci Rep 2021 Feb 15;11(1):3844. Epub 2021 Feb 15.

Medical Genetic Center, Guangdong Women and Children's Hospital, Guangzhou Medical University, 521-523 Xingnan Avenue, Panyu District, Guangzhou, 511442, People's Republic of China.

The aim of this study was to retrospectively compare hematological parameters among normal, α-, and β-thalassemia fetuses between 17 and 38 weeks of gestation. Pregnant women at risk of having fetuses with thalassemia major and underwent cordocentesis for prenatal diagnosis were recruited. Fetal cord blood samples were collected from 249 fetuses for hematological and DNA analysis. Fetuses were divided into subgroups according to thalassemia DNA genotypes. The average and gestational age of subjects were 27.95 ± 5.78 years and 27.78 ± 3.57 weeks, respectively. The distribution of α-thalassemia, β-thalassemia, and normal cases was 67.87%, 19.68%, and 12.45%, respectively. Significant differences in almost all the hematological parameters (HbF, HbA, Hb, HCT, MCV, MCH, MCHC, RDW, and NBRCs) were observed in three groups (P < 0.001, except for RBC, P = 0.446). These differences were also observed in four α-thalassemia subgroups (P < 0.001) and were associated with the number of defected genes. Similarly, in five β-thalassemia genotypes, HbF, HbA, RBC, MCV, MCH and NBRCs were presented differently (P < 0.05). Additionally, the trends in RBC, Hb, and HCT changes in three α-thalassemia subgroups (silent carrier, trait, and major) and β/β fetuses' MCV, MCH, and RDW levels with gestation age were opposite to those of normal fetuses. We compared the distribution of hematological parameters in fetuses affected by most genotypes of thalassemia, as well as their trends in relation to gestational age for the first time, which is a good reference for future studies and prenatal diagnostic practices. The investigated hematological parameters are also valuable in diagnosing and differentiating thalassemia.
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http://dx.doi.org/10.1038/s41598-021-82297-yDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7884422PMC
February 2021

Model Analysis of Post-Stimulation Effect on Axonal Conduction and Block.

IEEE Trans Biomed Eng 2021 Feb 5;PP. Epub 2021 Feb 5.

Objective: To reveal the possible contribution of changes in membrane ion concentration gradients and ion pump activity to axonal conduction/block induced by long-duration electrical stimulation.

Methods: A new model for conduction and block of unmyelinated axons based on the classical Hodgkin-Huxley (HH) equations is developed to include changes in Na+ and K+ concentrations and ion pumps. The effects of long-duration stimulation on axonal conduction/block is analyzed by computer simulation using this new model.

Results: The new model successfully simulates initiation, propagation, and block of action potentials induced by short-duration (multiple milliseconds) stimulations that do not significantly change the ion concentrations in the classical HH model. In addition, the activity-dependent effects such as action potential attenuation and broadening observed in animal studies are also successfully simulated by the new model. Finally, the model successfully simulates axonal block occurring after terminating a long-duration (multiple seconds) direct current (DC) stimulation as observed in recent animal studies and reveals 3 different mechanisms for the post-DC block of axonal conduction.

Conclusion: Ion concentrations and pumps play an important role in post-stimulation effects and activity-dependent effects on axonal conduction/block. The duration of stimulation is a determinant factor because it influences the total charges applied to the axon, which in turn determines the ion concentrations inside and outside the axon.

Significance: Despite recent clinical success of many neurostimulation therapies, the effects of long-duration stimulation on axonal conduction/block are poorly understood. This new model could significantly impact our understanding of the mechanisms underlying different neurostimulation therapies.
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http://dx.doi.org/10.1109/TBME.2021.3057522DOI Listing
February 2021

Metabolic footprint analysis of volatile metabolites to discriminate between different key time points in the fermentation and storage of starter cultures and probiotic Lactobacillus casei Zhang milk.

J Dairy Sci 2021 Mar 15;104(3):2553-2563. Epub 2021 Jan 15.

Key Laboratory of Dairy Biotechnology and Engineering, Ministry of Education, Inner Mongolia Agricultural University, Hohhot 010018, China; Key Laboratory of Dairy Products Processing, Ministry of Agriculture and Rural Affairs, Inner Mongolia Agricultural University, Hohhot 010018, China. Electronic address:

Interest has been growing in the co-fermentation of starter cultures with probiotic bacteria in milk. However, the representative metabolites and metabolic changes at different key time points during milk fermentation and storage in starter cultures and probiotic bacteria are still unclear. In this study, we used gas chromatography/mass spectrometry-based metabolomics to identify volatile metabolites and discriminate between 6 different time points [fermentation initiation (FI), fermentation curd (FC), fermentation termination (FT), storage 1 d (S1d), storage 7 d (S7d), and storage 14 d (S14d)] during the fermentation and storage of starter cultures and Lactobacillus casei Zhang milk. Of the 52 volatile metabolites identified, 15 contributed to discrimination of the 6 time points. Then, using the profile from the different time points, we analyzed pairwise comparisons (FI vs. FC; FC vs. FT; FT vs. S1d; S1d vs. S7d; S7d vs. S14d); these time-lapse comparisons showed metabolic progressions from one fermentation stage to the next. We found representative and exclusive metabolites at specific fermentation and storage time points. The greatest difference in metabolites occurred between FC and FT, and the metabolic profiles between S7d and S14d were most similar. Interestingly, decanoic acid, octanoic acid, and hexanoic acid reached their highest level at storage 14 d, indicating that the post-fermentation storage of fermented milk with L. casei Zhang may add more probiotic functions. This work provides detailed insight into the time-specific profiles of volatile metabolites and their dynamic changes; these data may be used for understanding and eventually predicting metabolic changes in milk fermentation and storage, where probiotic strains may be used.
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http://dx.doi.org/10.3168/jds.2020-18968DOI Listing
March 2021

Quantum-channel capacity of distributing orbital-angular-momentum states for underwater optical quantum communication.

J Opt Soc Am A Opt Image Sci Vis 2021 Jan;38(1):36-41

We employ non-diffractive Bessel-Gaussian beams to investigate the effect of oceanic turbulence on quantum communication protocols via behaviors of quantum-channel capacity and trace distance, based on the analytical expression of the phase structure function of an orbital-angular-momentum (OAM) beam in underwater wireless optical communication. Our results show that turbulence conditions with a larger inner-scale and outer-scale factors, higher dissipation rate of kinetic energy, lower dissipation rate of the mean-squared temperature, and smaller temperature-salinity contribution ratio are beneficial to quantum communication performance. Moreover, we show that the distribution protocol may be improved by distributing quantum superposition states instead of OAM eigenstates. We believe our work provides the first theoretical exploration of quantum-channel capacity in underwater OAM quantum communication.
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http://dx.doi.org/10.1364/JOSAA.402794DOI Listing
January 2021

Fermented milk containing Lactobacillus casei Zhang and Bifidobacterium animalis ssp. lactis V9 alleviated constipation symptoms through regulation of intestinal microbiota, inflammation, and metabolic pathways.

J Dairy Sci 2020 Dec 23;103(12):11025-11038. Epub 2020 Oct 23.

Key Laboratory of Dairy Biotechnology and Engineering, Ministry of Education, Key Laboratory of Dairy Products Processing, Ministry of Agriculture, Inner Mongolia Agricultural University, Huhhot 010018, China. Electronic address:

Studies suggest that probiotics and fermented milk can improve defecation in constipated patients. However, the mechanism of fermented milk containing probiotics on constipation remains poorly understood. Volunteers with chronic constipation symptoms were recruited and given 200 g/d of fermented milk containing Lactobacillus casei Zhang and Bifidobacterium animalis ssp. lactis V9 (PFM) for 4 wk. Clinical symptoms, cytokines, metagenomics, and metabolomics were evaluated in constipated participants before and after PFM intervention. After PFM intervention, we observed significant improvement of constipation symptoms. In the serum samples, the anti-inflammatory cytokine IL-10 increased and the proinflammatory cytokine C-reactive protein and lipopolysaccharides decreased. Metagenomics results showed that the increase of B. animalis was correlated with an increase in defecation frequency. Fatty acid biosynthesis and bile acid biosynthesis in stool samples as well as carnitine shuttle, vitamin E metabolism, and ascorbate and aldarate metabolism were identified as significantly altered metabolic pathways. Acylcarnitine, located on the carnitine shuttle pathway, had a significantly positive correlation with defecation frequency. It was speculated that PFM may contribute to alleviating constipation symptoms through 3 potential mechanisms: fine-tuning gastrointestinal microbiota, fighting inflammation, and regulating metabolic pathways.
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http://dx.doi.org/10.3168/jds.2020-18639DOI Listing
December 2020

Compound heterozygosity for hemoglobin variant Hb-Broomhill and the Southeast Asian α-thalassemia deletion does not worsen outcome: a case report of two unrelated patients.

J Int Med Res 2020 Nov;48(11):300060520967825

Medical Genetic Center, Guangdong Women and Children Hospital, Guangzhou, Guangdong, China.

We report two unrelated cases of compound heterozygosity for hemoglobin (Hb) variant Broomhill and the Southeast Asian (- - /) α-thalassemia deletion, whose clinical features and laboratory findings have never been reported. Hematological analyses revealed abnormal values for both cases as α-thalassemia traits, and capillary electrophoresis suggested an abnormal peak that was incompletely separated from the Hb A peak. A suspension array system and Sanger sequencing were used to characterize the genotypes. Sanger sequencing confirmed the presence of Hb Broomhill [α114(GH2)Pro→Ala; : c.343C>G]. Eventually, both cases were accurately diagnosed as compound heterozygotes for Hb Broomhill and the (- - /) α-thalassemia deletion, which is the first known report of these variants. This information will be useful when providing appropriate genetic counselling and prenatal diagnosis.
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http://dx.doi.org/10.1177/0300060520967825DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7683915PMC
November 2020

Bladder underactivity induced by prolonged pudendal afferent activity in cats.

Am J Physiol Regul Integr Comp Physiol 2021 01 4;320(1):R80-R87. Epub 2020 Nov 4.

Department of Urology, University of Pittsburgh, Pittsburgh, Pennsylvania.

The purpose of this study was to determine the effects of pudendal nerve stimulation (PNS) on reflex bladder activity and develop an animal model of underactive bladder (UAB). In six anesthetized cats, a bladder catheter was inserted via the urethra to infuse saline and measure pressure. A cuff electrode was implanted on the pudendal nerve. After determination of the threshold intensity (T) for PNS to induce an anal twitch, PNS (5 Hz, 0.2 ms, 2 T or 4 T) was applied during cystometrograms (CMGs). PNS (4-6 T) of 30-min duration was then applied repeatedly until bladder underactivity was produced. Following stimulation, control CMGs were performed over 1.5-2 h to determine the duration of bladder underactivity. When applied during CMGs, PNS (2 T and 4 T) significantly ( < 0.05) increased bladder capacity while PNS at 4 T also significantly ( < 0.05) reduced bladder contraction amplitude, duration, and area under contraction curve. Repeated application of 30-min PNS for a cumulative period of 3-8 h produced bladder underactivity exhibiting a significantly ( < 0.05) increased bladder capacity (173 ± 14% of control) and a significantly ( < 0.05) reduced contraction amplitude (50 ± 7% of control). The bladder underactivity lasted more than 1.5-2 h after termination of the prolonged PNS. These results provide basic science evidence supporting the proposal that abnormal afferent activity from external urethral/anal sphincter could produce central inhibition that underlies nonobstructive urinary retention (NOUR) in Fowler's syndrome. This cat model of UAB may be useful to investigate the mechanism by which sacral neuromodulation reverses NOUR in Fowler's syndrome.
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http://dx.doi.org/10.1152/ajpregu.00239.2020DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7847056PMC
January 2021

High-performance terahertz vortex beam generator based on square-split-ring metasurfaces.

Opt Lett 2020 Nov;45(21):6054-6057

Generating a vortex beam is a fundamental task due to the potential applications in wireless communication. Here we propose a kind of high-performance terahertz vortex beam generator with several topological numbers based on the square-split-ring metasurfaces. Via the Fabry-Perot resonance effect of the structure, the transmittance of an orthogonal polarization mode could be remarkably enhanced. We use a Laguerre-Gaussian (LG) mode for illustration and then simulate the far-field propagation of the LG beam by using phase superposition of focusing lens and vortex phase plates. The theoretical and simulation results agree well, which implies a bright application prospect.
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http://dx.doi.org/10.1364/OL.401231DOI Listing
November 2020

Chemical exchange sensitive MRI of glucose uptake using xylose as a contrast agent.

Magn Reson Med 2021 04 26;85(4):1953-1961. Epub 2020 Oct 26.

Department of Radiology, University of Pittsburgh, Pittsburgh, Pennsylvania, USA.

Purpose: Glucose and its analogs can be detected by CEST and chemical exchange spin-lock (CESL) MRI techniques, but sensitivity is still a bottleneck for human applications. Here, CESL and CEST sensitivity and the effect of injection on baseline physiology were evaluated for a glucose analog, xylose.

Methods: The CEST and CESL sensitivity were evaluated at 9.4 T in phantoms and by in vivo rat experiments with 0.5 and 1 g/kg xylose injections. Arterial blood glucose level was sampled before and after 1 g/kg xylose injection. The effect of injection on baseline neuronal activity was measured by electrophysiology data during injections of saline, xylose, and 2-deoxy-D-glucose.

Results: In phantoms, xylose shows similar chemical exchange sensitivity and pH-dependence with that of glucose. In rat experiments with a bolus injection, CESL shows higher sensitivity in the detection of xylose than CEST, and the sensitivity of xylose is much higher than glucose. Injection of xylose does not significantly affect blood glucose level and baseline neural activity for 1-g/kg and 0.6-g/kg doses, respectively.

Conclusion: Due to its relatively high sensitivity and safety, xylose is a promising contrast agent for the study of glucose uptake.
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http://dx.doi.org/10.1002/mrm.28557DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7875248PMC
April 2021

Establishment and application of a novel method based on single nucleotide polymorphism analysis for detecting β-globin gene cluster deletions.

Sci Rep 2020 10 26;10(1):18298. Epub 2020 Oct 26.

Medical Genetic Centre, Guangdong Women and Children's Hospital, Guangzhou Medical University, 521-523 Xingnan Avenue, Panyu District, Guangzhou, 511400, China.

β-Globin gene mutations reduce or terminate the production of beta globin chains, of which approximately 10% are large deletions within the β-globin gene cluster. Because gene deletion leads to loss of heterozygosity at single nucleotide polymorphism (SNP), a novel method for detecting β-globin gene cluster deletions based on SNP heterozygosity analysis was established in this study. The location range of SNPs was selected according to the breakpoint of β-globin gene cluster deletions. SNPs were screened using bioinformatics analysis and population sequencing data. A novel method which enables genotyping of multiplex SNPs based on tetra-primer ARMS-PCR was designed and optimized. Forty clinical samples were tested in parallel by this method and MLPA to verify the performance of this method for detecting β-globin gene cluster deletion. Six informative SNPs were obtained, achieving heterozygote coverage of 93.3% in normal individuals. Genotyping of six SNPs were successfully integrated into two multiplex tetra-primer ARMS-PCR reactions. The sensitivity, specificity, positive predictive value and negative predictive value of the method for detecting β-globin gene cluster deletion were 100%, 96.30%, 92.86%, and 100%, respectively. This is a simple, cost-effective and novel method for detecting β-globin gene cluster deletions, which may be suitable for use in combination with MLPA for thalassemia molecular testing.
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http://dx.doi.org/10.1038/s41598-020-75507-6DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7588424PMC
October 2020

Water flow inside various geometric nano-confinement channels.

Phys Chem Chem Phys 2020 Nov 23;22(42):24633-24639. Epub 2020 Oct 23.

College of Water Resources and Architectural Engineering, Northwest A&F University, 712100 Yangling, China.

In nano-confined systems, the properties of a fluid are different from those of macroscopic systems, and the properties of a nanotube can significantly affect water transport. However, our knowledge of the effects of nanotube shape is far from adequate. In the present work, we study the properties of a fluid transporting in different nano-confined configurations by molecular dynamics simulations. This study is aimed at gaining insight into the transport of water molecules in carbon nanotubes with different configurations. We find that the closer of channel shape to the circular nanotube (more sides of the channel), the lower friction coefficient of the solid-liquid interface has and the friction coefficient of nanochannels increases with R when R < 1.0 nm. The friction coefficient converges to a stable value (close to the friction coefficient of graphene/water) when R > 1.0 nm. A variety of configurations leads to the variation of the fluid properties in nanotubes. Our results can be applied to the nanofluid properties of a complex channel structure and water nanochannel microscopic design.
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http://dx.doi.org/10.1039/d0cp04491aDOI Listing
November 2020

Poststimulation Block of Pudendal Nerve Conduction by High-Frequency (kHz) Biphasic Stimulation in Cats.

Neuromodulation 2020 Aug 5;23(6):747-753. Epub 2019 Nov 5.

Department of Urology, University of Pittsburgh, Pittsburgh, PA, USA.

Objective: To determine the relationship between various parameters of high-frequency biphasic stimulation (HFBS) and the recovery period of post-HFBS block of the pudendal nerve in cats.

Materials And Methods: A tripolar cuff electrode was implanted on the pudendal nerve to deliver HFBS in ten cats. Two hook electrodes were placed central or distal to the cuff electrode to stimulate the pudendal nerve and induce contractions of external urethral sphincter (EUS). A catheter was inserted toward the distal urethra to slowly perfuse the urethra and record the back-up pressure generated by EUS contractions. After determining the block threshold (T), HFBS (6 or 10 kHz) of different durations (1, 5, 10, 20, 30 min) and intensities (1T or 2T) was used to produce the post-HFBS block.

Results: HFBS at 10 kHz and 1T intensity must be applied for at least 30 min to induce post-HFBS block. However, 10 kHz HFBS at a higher intensity (2T) elicited post-HFBS block after stimulation of only 10 min; and 10 kHz HFBS at 2T for 30 min induced a longer-lasting (1-3 h) post-HFBS block that fully recovered with time. HFBS of 5-min duration at 6 kHz produced a longer period (20.4 ± 2.1 min, p < 0.05, N = 5 cats) of post-HFBS block than HFBS at 10 kHz (9.5 ± 2.1 min).

Conclusion: HFBS of longer duration, higher intensity, and lower frequency can produce longer-lasting reversible post-HFBS block. This study is important for developing new methods to block nerve conduction by HFBS.
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http://dx.doi.org/10.1111/ner.13060DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7447838PMC
August 2020

Pudendal Nerve Block by Low-Frequency (≤1 kHz) Biphasic Electrical Stimulation.

Neuromodulation 2020 Aug 6. Epub 2020 Aug 6.

Department of Urology, University of Pittsburgh, Pittsburgh, PA, USA.

Objectives: To test the hypothesis that poststimulation block of nerve conduction can be achieved by low-frequency (≤1 kHz) biphasic stimulation (LFBS).

Materials And Methods: A tripolar cuff electrode was placed around the pudendal nerve in cats to deliver LFBS (1 kHz, 500 Hz, and 100 Hz). Two bipolar hook electrodes were placed central and distal to the cuff electrode to induce external urethral sphincter (EUS) contractions. A catheter was inserted into the urethra to record EUS contraction pressure. Pudendal nerve block by LFBS was confirmed by the failure of the central hook electrode stimulation to induce EUS contractions, while the distal hook electrode stimulation still induced contractions.

Results: Pudendal nerve conduction was completely blocked by LFBS at different frequencies (1 kHz, 500 Hz, and 100 Hz) after terminating LFBS. The post-LFBS block induced at the minimal stimulation intensity and duration was fully reversible within the same time period (10-15 min on average) for the three frequencies. However, the stimulation duration to induce block significantly (p < 0.05) increased from 23 ± 8 sec to 95 ± 14 sec when frequency increased from 100 Hz to 1 kHz.

Conclusion: This study discovered that LFBS (≤1 kHz), like high-frequency (≥5 kHz) biphasic stimulation (HFBS), can induce poststimulation block. The result provides support for the theory that biphasic stimulation waveforms block axonal conduction by changing intracellular and extracellular ion concentrations. The post-LFBS block provides the opportunity to develop new neuromodulation devices for clinical applications where initial nerve firing is acceptable.
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http://dx.doi.org/10.1111/ner.13241DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7921907PMC
August 2020

Characteristics of a bidirectional multifunction focusing and plasmon-launching lens with multiple periscope-like waveguides.

Opt Express 2020 Jul;28(14):20334-20344

A device incorporating a series of periscope-like waveguides to achieve bidirectional focusing and plasmon launching is proposed. Optimizing the number, positions, and dimensions of the waveguides and tuning the waveguide optical paths both produce the required phase shifts to shape wavefronts and achieve constructive interference at the desired points. Due to the symmetry and reversibility of the structure, the lens can focus the light incident on both sides. Energy redistribution to a specific multi-focus can also be achieved by applying appropriate phase shifts. This simple and high performance structure makes the bidirectional plasmonic launcher easy to implement in various application situations.
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http://dx.doi.org/10.1364/OE.395816DOI Listing
July 2020

Superficial peroneal neuromodulation of nonobstructive urinary retention in cats.

Neurourol Urodyn 2020 08 16;39(6):1679-1686. Epub 2020 Jun 16.

Department of Urology, University of Pittsburgh, Pittsburgh, Pennsylvania.

Aims: To determine if superficial peroneal nerve stimulation (SPNS) can improve nonobstructive urinary retention (NOUR).

Methods: In α-chloralose anesthetized cats, NOUR was induced by repetitive application (4-16 times) of 30-minute tibial nerve stimulation (TNS: 5 Hz frequency, 0.2 ms pulse width) at 4 to 6 times threshold intensity (T) for inducing toe twitches. SPNS (1 Hz, 0.2 ms) at 2 to 4 times threshold intensity (T) for inducing posterior thigh muscle contractions was applied either continuously (SPNSc) during a cystometrogram (CMG) or during voiding (SPNSv) by a surgically implanted cuff electrode or by skin surface electrodes to determine if the stimulation reduced NOUR induced by prolonged TNS.

Results: During control CMGs, efficient (86.4% ± 5.5%) voiding occurred with a postvoid residual (PVR) volume equal to 14.9% ± 6.2% of control bladder capacity. NOUR elicited by prolonged TNS significantly (P < .05) increased bladder capacity to 168.6% ± 15.5% of control, reduced voiding efficiency to 30.4% ± 4.8%, and increased PVR to 109% ± 9.2% of control. Using the implanted cuff electrode, SPNSc and SPNSv significantly (P < .05) increased voiding efficiency to 66.7% ± 7.4% and 65.0% ± 5.9%, respectively, and reduced PVR to 52.2% ± 11.4% and 64.3% ± 11.6%, respectively. SPNSc but not SPNSv significantly (P < .05) reduced bladder capacity to 133.4% ± 15% of control. Transcutaneous SPNSv but not SPNSc also significantly (P < .05) reversed the TNS-induced NOUR responses.

Conclusions: This study shows that SPNS is effective in reversing NOUR induced by prolonged TNS. Transcutaneous SPNS provides the opportunity to develop a noninvasive neuromodulation therapy for NOUR to treat more patients than current sacral neuromodulation therapy.
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http://dx.doi.org/10.1002/nau.24438DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7927909PMC
August 2020

Photonic Bragg waveguide platform for multichannel resonant sensing applications in the THz range.

Biomed Opt Express 2020 May 10;11(5):2476-2489. Epub 2020 Apr 10.

School of Science, Jiangnan University, 1800 Lihu Ave, Wuxi 214122, China.

In this paper, we study a photonic Bragg waveguide sensor for resonant sensing applications in the THz range. In order to enhance the resolution and detectivity of the sensor, we modify the relatively broad transmission spectrum of the Bragg waveguide with spectrally narrow transmission dips by creating a geometrical defect in Bragg reflector and causing anti-crossing phenomenon between the core-guided mode and defect mode. The spectral position of the resonant dip is highly sensitive to the thickness variation in the vicinity of the waveguide core. By designing and manufacturing a Bragg waveguide which includes several sections with different defect layer thicknesses, we can interrogate more than one sample simultaneously and thereby realize multichannel resonant sensing by directly tracking the independent resonant dips. Furthermore, we demonstrate the waveguide platform for online monitoring of the thickness variation of lactose powders, which is captured on the waveguide core via a centrifugal force using a home-built rotating setup. Additionally, we also demonstrate the waveguide for fingerprint detection of powder analytes, which further enriches the sensing scenario of the sensing platform. Finally, we discuss the advantages and the spectral tailoring flexibility of the THz Bragg waveguides sensors for future implementations.
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http://dx.doi.org/10.1364/BOE.390100DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7249813PMC
May 2020

Inversion Method Characterization of Graphene-Based Coordination Absorbers Incorporating Periodically Patterned Metal Ring Metasurfaces.

Nanomaterials (Basel) 2020 Jun 2;10(6). Epub 2020 Jun 2.

School of Science, Jiangnan University, Wuxi 214122, China.

In this paper, we propose a tunable coordinated multi-band absorber that combines graphene with metal-dielectric-metal structures for the realization of multiple toward perfect absorption. The parametric inversion method is used to extract the equivalent impedance and explain the phenomena of multiple-peak absorption. With the change of the Fermi level, equivalent impedances were extracted, and the peculiarities of the individual multiple absorption peaks to change were determined. By changing the structure parameters of gold rings, we obtain either multiple narrow-band absorption peaks or a broadband absorption peak, with the bandwidth of 0.8 μm where the absorptance is near 100%. Therefore, our results provide new insights into the development of tunable multi-band absorbers and broadband absorbers that can be applied to terahertz imaging in high-performance coordinate sensors and other promising optoelectronic devices.
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http://dx.doi.org/10.3390/nano10061102DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7353306PMC
June 2020

Thermal block of mammalian unmyelinated C fibers by local cooling to 15-25°C after a brief heating at 45°C.

J Neurophysiol 2020 06 6;123(6):2173-2179. Epub 2020 May 6.

Department of Urology, University of Pittsburgh, Pittsburgh, Pennsylvania.

The purpose of this study was to examine the changes in cold block of unmyelinated C fibers in the tibial nerve by preconditioning with heating and to develop a safe method for thermal block of C-fiber conduction. In seven cats under α-chloralose anesthesia, C-fiber-evoked potentials elicited by electrical stimulation were recorded on the tibial nerve during block of axonal conduction induced by exposing a small segment (9 mm) of the nerve to cooling (from 35°C to ≤5°C) or heating (45°C). Before heating, partial, reproducible, and reversible cold block was first detected at a threshold cold block temperature of 15°C and complete cold block occurred at a temperature of ≤5°C. After the nerve was heated at 45°C for 5-35 min, the threshold cold block temperature significantly ( < 0.05) increased from 15°C to 25°C and the complete cold block temperature significantly ( < 0.05) increased from ≤5°C to 15°C on average. The increased cold block temperatures persisted for the duration of the experiments (30-100 min) while the amplitude of the C-fiber-evoked potential measured at 35°C recovered significantly ( < 0.05) to ~80% of control. This study discovered a novel thermal method to block mammalian C fibers at an elevated temperature (15-25°C), providing the opportunity to develop a thermal nerve block technology to suppress chronic pain of peripheral origin. The interaction between heating and cooling effects on C-fiber conduction indicates a possible interaction between different temperature-sensitive channels known to be present in the mammalian C fibers. Our study discovered that the temperature range for producing a partial to complete cold block of mammalian C-fiber axons can be increased from 5-15°C to 15-25°C on average after a preheating at 45°C. This discovery raises many basic scientific questions about the influence of temperature on nerve conduction and block. It also raises the possibility of developing a novel implantable nerve block device to treat many chronic diseases including chronic pain.
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http://dx.doi.org/10.1152/jn.00133.2020DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7311731PMC
June 2020

Response of hypogastric afferent fibers to bladder distention or irritation in cats.

Exp Neurol 2020 07 3;329:113301. Epub 2020 Apr 3.

Department of Pharmacology and Chemical Biology, University of Pittsburgh, Pittsburgh, PA, USA. Electronic address:

The goal of this study in anesthetized cats was to identify silent hypogastric nerve (HGN) afferent fibers that do not respond to bladder distention but become responsive after chemical irritation of the bladder. The HGN was split into multiple filaments small enough for recording action potentials from single or multiple afferent fibers. The bladder was distended by infusion of either saline or 0.5% acetic acid (AA) through a urethral catheter while recording intravesical pressure. A total of 90 HGN filaments from 17 cats responded to bladder distention with saline or AA. Three types of HGN afferents were identified. The first type was non-nociceptive mechano-sensitive that responded to bladder distention at normal physiological pressures (10-40 cmHO). The second type was nociceptive mechano-sensitive that only responded to high-pressure (50-80 cmHO) bladder distention with saline but responded to low-pressure bladder distention after sensitization with AA. The third type was chemo-sensitive nociceptive that was silent even during high-pressure bladder distention but after sensitization with AA did respond to low-pressure bladder distention. These results indicate that HGN afferents as well as pelvic nerve afferents may play a role in bladder nociception. The HGN afferent fibers that are silent during bladder distention at normal physiological pressures but become responsive after chemical irritation are important for understanding the possible pathophysiological mechanism underlying bladder allodynia in painful bladder syndrome.
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http://dx.doi.org/10.1016/j.expneurol.2020.113301DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7237284PMC
July 2020

Additive Inhibition of Reflex Bladder Activity Induced by Bilateral Pudendal Neuromodulation in Cats.

Front Neurosci 2020 7;14:80. Epub 2020 Feb 7.

Department of Urology, University of Pittsburgh, Pittsburgh, PA, United States.

Objective: To determine the inhibitory effect on bladder activity induced by bilateral pudendal neuromodulation.

Methods: In 10 cats under anesthesia, two tripolar cuff electrodes were implanted bilaterally on the pudendal nerves for stimulation. A double lumen catheter was inserted into the bladder through the urethra to infuse saline and measure bladder pressure. During repeated cystometrograms (CMGs) pudendal nerve stimulation (PNS: 5 Hz, 0.2 ms, 5-15 min) was applied unilaterally or bilaterally at 1- or 2-times intensity threshold () for inducing anal sphincter twitching. PNS inhibition was indicated by the increase in bladder capacity measured by CMGs.

Results: Unilateral PNS at 1T did not significantly increase bladder capacity, but at 2T significantly ( < 0.05) increased bladder capacity by about 30%. Bilateral PNS at 1T also failed to increase bladder capacity, but at 2T significantly ( < 0.05) increased bladder capacity by about 60%, indicating an additive effect induced by the bilateral 2T PNS. Unilateral 1T PNS did not enhance the inhibitory effect induced by contra-lateral 2T PNS.

Conclusion: This study in anesthetized cats reveals that an additive inhibition of reflex bladder activity can be induced by bilateral pudendal neuromodulation, indicating that bilateral PNS might achieve better therapeutic efficacy in treating overactive bladder (OAB) than unilateral PNS.
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http://dx.doi.org/10.3389/fnins.2020.00080DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7020809PMC
February 2020

Characterization of potentially probiotic lactic acid bacteria and bifidobacteria isolated from human colostrum.

J Dairy Sci 2020 May 26;103(5):4013-4025. Epub 2020 Feb 26.

Key Laboratory of Dairy Biotechnology and Engineering, Ministry of Education of China, Inner Mongolia Agricultural University, Hohhot, 010018, China; Key Laboratory of Dairy Products Processing, Ministry of Agriculture and Rural Affairs of China, Inner Mongolia Agricultural University, Hohhot, 010018, China; Inner Mongolia Key Laboratory of Dairy Biotechnology and Engineering, Inner Mongolia Agricultural University, Hohhot, 010018, China. Electronic address:

Breast milk is the main source of nutrition for infants; it contains considerable microflora that can be transmitted to the infant endogenously or by breastfeeding, and it plays an important role in the maturation and development of the immune system. In this study, we isolated and identified lactic acid bacteria (LAB) from human colostrum, and screened 2 strains with probiotic potential. The LAB isolated from 40 human colostrum samples belonged to 5 genera: Lactobacillus, Bifidobacterium, Streptococcus, Enterococcus, and Staphylococcus. We also isolated Propionibacterium and Actinomyces. We identified a total of 197 strains of LAB derived from human colostrum based on their morphology and 16S rRNA sequence, among them 8 strains of Bifidobacterium and 10 strains of Lactobacillus, including 3 Bifidobacterium species and 4 Lactobacillus species. The physiological and biochemical characteristics of strains with good probiotic characteristics were evaluated. The tolerances of some of the Bifidobacterium and Lactobacillus strains to gastrointestinal fluid and bile salts were evaluated in vitro, using the probiotic strains Bifidobacterium lactis BB12 and Lactobacillus rhamnosus GG as controls. Among them, B. lactis Probio-M8 and L. rhamnosus Probio-M9 showed survival rates of 97.25 and 78.33% after digestion for 11 h in artificial gastrointestinal juice, and they exhibited growth delays of 0.95 and 1.87 h, respectively, in 0.3% bile salts. These two strains have the potential for application as probiotics and will facilitate functional studies of probiotics in breast milk and the development of human milk-derived probiotics.
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http://dx.doi.org/10.3168/jds.2019-17602DOI Listing
May 2020

Adaptation of Lactobacillus plantarum to Ampicillin Involves Mechanisms That Maintain Protein Homeostasis.

mSystems 2020 Jan 28;5(1). Epub 2020 Jan 28.

Key Laboratory of Dairy Biotechnology and Engineering, Ministry of Education, Inner Mongolia Agricultural University, Huhhot, China

The widespread use of antibiotics has caused great concern in the biosafety of probiotics. In this study, we conducted a 12-month adaptive laboratory evolution (ALE) experiment to select for antibiotics-adapted P-8, a dairy-originated probiotic bacterium. During the ALE process, the ampicillin MIC for the parental P-8 strain increased gradually and reached the maximum level of bacterial fitness. To elucidate the molecular mechanisms underlying the ampicillin-resistant phenotype, we comparatively analyzed the genomes and proteomes of the parental strain ( P-8) and two adapted lines ( 400g and 1600g). The adapted lines showed alterations in their carbon, amino acid, and cell surface-associated metabolic pathways. Then, gene disruption mutants were created to determine the role of six highly expressed genes in contributing to the enhanced ampicillin resistance. Inactivation of an ATP-dependent Clp protease/the ATP-binding subunit ClpL, a small heat shock protein, or a hypothetical protein resulted in partial but significant phenotypic reversion, confirming their necessary roles in the bacterial adaptation to ampicillin. Genomic analysis confirmed that none of the ampicillin-specific differential expressed genes were flanked by any mobile genetic elements; thus, even though long-term exposure to ampicillin upregulated their expression, there is low risk of spread of these genes and adapted drug resistance to other bacteria via horizontal gene transfer. Our study has provided evidence of the biosafety of probiotics even when used in the presence of antibiotics. Antibiotic resistance acquired by adaptation to certain antibiotics has led to growing public concerns. Here, a long-term evolution experiment was used together with proteomic analysis to identify genes/proteins responsible for the adaptive phenotype. This work has provided novel insights into the biosafety of new probiotics with high tolerance to antibiotics.
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http://dx.doi.org/10.1128/mSystems.00853-19DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6989132PMC
January 2020

Prolonged nonobstructive urinary retention induced by tibial nerve stimulation in cats.

Am J Physiol Regul Integr Comp Physiol 2020 02 8;318(2):R428-R434. Epub 2020 Jan 8.

Department of Urology, University of Pittsburgh, Pittsburgh, Pennsylvania.

Nonobstructive urinary retention (NOUR) is a medical condition without an effective drug treatment, but few basic science studies have focused on this condition. In α-chloralose-anesthetized cats, the bladder was cannulated via the dome and infused with saline to induce voiding that could occur without urethral outlet obstruction. A nerve cuff electrode was implanted for tibial nerve stimulation (TNS). The threshold (T) intensity for TNS to induce toe twitch was determined initially. Repeated (6 times) application of 30-min TNS (5 Hz, 0.2 ms, 4-6T) significantly ( < 0.05) increased bladder capacity to 180% of control and reduced the duration of the micturition contraction to 30% of control with a small decrease in contraction amplitude (80% of control), which resulted in urinary retention with a low-voiding efficiency of 30% and a large amount of residual volume equivalent to 130% of control bladder capacity. This NOUR condition persisted for >2 h after the end of repeated TNS. However, lower frequency TNS (1 Hz, 0.2 ms, 4T) applied during voiding partially reversed the NOUR by significantly ( < 0.05) increasing voiding efficiency to 60% and reducing residual volume to 70% of control bladder capacity without changing bladder capacity. These results revealed that tibial nerve afferent input can activate either an excitatory or an inhibitory central nervous system mechanism depending on afferent firing frequencies (1 vs. 5 Hz). This study established the first NOUR animal model that will be useful for basic science research aimed at developing new treatments for NOUR.
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http://dx.doi.org/10.1152/ajpregu.00277.2019DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7052595PMC
February 2020

The Role of lncRNAs in Osteogenic Differentiation of Bone Marrow Mesenchymal Stem Cells.

Curr Stem Cell Res Ther 2020 ;15(3):243-249

Department of Orthopaedic, Shaanxi Provincial People's Hospital, Xi'an 710068, China.

Bone Marrow Mesenchymal Stem Cells (BMSCs) are one of the primary cells found in the bone marrow, and they can differentiate into osteoblasts, chondrocytes, adipocytes and even myoblasts, and are, therefore, considered pluripotent cells. Because of their multipotential differentiation, selfrenewal capability, immunomodulation and other potential activities, BMSCs have become an important source of seed cells for gene therapy, tissue engineering, cell replacement therapy and regenerative medicine. Long non-coding RNA (lncRNA) is an RNA molecule greater than 200 nucleotides in length that is expressed in a variety of species, including animals, plants, yeast, prokaryotes, and viruses, but lacks an apparent open reading frame, and does not have the function of translation into proteins. Many studies have shown that lncRNAs play an important role in the osteogenic differentiation of BMSCs. Here, we describe the role of lncRNAs in the osteogenic differentiation of BMSCs, in order to provide a new theoretical and experimental basis for bone tissue engineering and clinical treatment.
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http://dx.doi.org/10.2174/1574888X15666191227113742DOI Listing
December 2020

Multiple-image optical encryption based on phase retrieval algorithm and fractional Talbot effect.

Opt Express 2019 Nov;27(24):35096-35107

A new multiple-image optical encryption scheme based on phase retrieval algorithm and fractional Talbot effect is proposed. In encryption process, by using Fresnel domain phase retrieval algorithm, each image is encoded into a pure phase distribution with different spatial constraints. The spatial constraints are chosen as complementary square aperture array. A Talbot illuminator is designed according to the fractional Talbot effect, which is treated as a decoder to obtain the designed square aperture array. Then all obtained phase distributions are combined into the final ciphertext image. In decryption process, the images can be decoded from the ciphertext by using the Talbot illuminator and keys. Benefit from the use of fractional Talbot effect, the demultiplexing setup of the cryptosystem is very simple and straightforward, with no need of lens. The simulation results prove that the multiplexing capability is considerably enhanced. At the same time, the security analysis proves that the system can resist various attacks.
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http://dx.doi.org/10.1364/OE.27.035096DOI Listing
November 2019

High-Efficiency and Broadband Near-Infrared Bi-Functional Metasurface Based on Rotary Different-Size Silicon Nanobricks.

Nanomaterials (Basel) 2019 Dec 7;9(12). Epub 2019 Dec 7.

School of Electrical Engineering and Intelligentization, Dongguan University of Technology, Dongguan 523808, China.

Several novel spin-dependent bi-functional metasurfaces consisting of different-sized rotary silicon nanobricks have been proposed and numerically investigated based on the Pancharatnam-Berry phase and structural phase simultaneously. Here, a transmission mechanism is strictly deduced, which can avoid crosstalk from the multiplexed bi-functional metasurface. Four kinds of high-efficiency bi-functional devices have been designed successfully at infrared wavelengths, including a spin-dependent bi-functional beam deflector, a spin-dependent bi-functional metalens, a bi-functional metasurface with spin-dependent focusing and deflection function, and a spin-dependent bi-functional vortex phase plate. All of the results demonstrate the superior performances of our designed devices. Our work opens up new doors toward building novel spin-dependent bi-functional metasurfaces, and promotes the development of bi-functional devices and spin-controlled photonics.
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http://dx.doi.org/10.3390/nano9121744DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6955931PMC
December 2019