Publications by authors named "Jingwen He"

22 Publications

  • Page 1 of 1

A Reliable High-Throughput Screening Model for Antidepressant.

Int J Mol Sci 2021 Sep 1;22(17). Epub 2021 Sep 1.

State Key Laboratory of Natural Medicines, China Pharmaceutical University, Nanjing 210009, China.

Depression is the most frequent affective disorder and is the leading cause of disability worldwide. In order to screen antidepressants and explore molecular mechanisms, a variety of animal models were used in experiments, but there is no reliable high-throughput screening method. Zebrafish is a common model organism for mental illness such as depression. In our research, we established chronic unpredictable mild stress (CUMS) models in C57BL/6 mice and zebrafish; the similarities in behavior and pathology suggest that zebrafish can replace rodents as high-throughput screening organisms. Stress mice (ip., 1 mg/kg/d, 3 days) and zebrafish (10 mg/L, 20 min) were treated with reserpine. As a result, reserpine caused depression-like behavior in mice, which was consistent with the results of the CUMS mice model. Additionally, reserpine reduced the locomotor ability and exploratory behavior of zebrafish, which was consistent with the results of the CUMS zebrafish model. Further analysis of the metabolic differences showed that the reserpine-induced zebrafish depression model was similar to the reserpine mice model and the CUMS mice model in the tyrosine metabolism pathway. The above results showed that the reserpine-induced depression zebrafish model was similar to the CUMS model from phenotype to internal metabolic changes and can replace the CUMS model for antidepressants screening. Moreover, the results from this model were obtained in a short time, which can shorten the cycle of drug screening and achieve high-throughput screening. Therefore, we believe it is a reliable high-throughput screening model.
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http://dx.doi.org/10.3390/ijms22179505DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8430800PMC
September 2021

PTSD Among Healthcare Workers During the COVID-19 Outbreak: A Study Raises Concern for Non-medical Staff in Low-Risk Areas.

Front Psychiatry 2021 12;12:696200. Epub 2021 Jul 12.

Department of Medical Psychology, Naval Medical University, Shanghai, China.

To investigate the prevalence of sleep quality and post-traumatic stress disorder (PTSD) symptoms of healthcare workers (HCWs) and identify the determinants for PTSD symptoms among HCWs in high-risk and low-risk areas during the COVID-19 outbreak in China. The Pittsburgh Sleep Quality Index and the Impact of Event Scale were used to assess sleep quality and symptoms of PTSD of 421 Chinese HCWs, respectively, from January 30 to March 2, 2020. The influencing factors of PTSD symptoms were identified by univariate analysis and multiple regression. The incidence of HCWs getting PTSD symptoms were 13.2%. HCWs from high-risk areas had significantly poorer sleep quality ( < 0.001). Poor sleep quality was the risk factor of PTSD symptoms for HCWs from high-risk ( = 0.018) and low-risk areas ( < 0.001). Furthermore, non-medical staff were found to be the risk factor for PTSD symptoms only in low-risk areas. HCWs in Hubei had poorer sleep quality. Non-medical HCWs from low-risk areas were associated with more severe PTSD symptoms. Mental health programs should be considered for HCWs, especially those who are often overlooked.
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http://dx.doi.org/10.3389/fpsyt.2021.696200DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8310947PMC
July 2021

Zebrafish Model for Screening Antiatherosclerosis Drugs.

Oxid Med Cell Longev 2021 22;2021:9995401. Epub 2021 Jun 22.

School of Traditional Chinese Pharmacy, China Pharmaceutical University, Nanjing, 211198 Jiangsu, China.

This study is aimed at establishing a zebrafish model of AS, which can be applied for high-throughput screening anti-AS drugs. A zebrafish AS model was induced by high cholesterol diet (HCD) and lipopolysaccharide (LPS). In the early stage of modeling, HCD induced zebrafish to show some early symptoms similar to human AS, mainly cholesterol accumulation, vascular inflammation, lipid metabolism disorder, and oxidative stress. In addition to lipid metabolism disorders, LPS also induced the same symptoms. And when HCD and LPS exist at the same time, these AS symptoms in zebrafish become more severe. When the modeling time reached 45 days, HCD and LPS induce the formation of plaques in zebrafish blood vessels, and these plaques contain fibrous tissue and lipids, which are similar to human AS plaques. We also evaluated the efficacy of some anti-AS drugs (atorvastatin, aspirin, and vitamin C) through these zebrafish AS models. The results found that atorvastatin can significantly reduce the symptoms of AS induced by HCD and LPS, and aspirin and vitamins can significantly reduce the symptoms of AS induced by LPS. It is feasible to use zebrafish to establish an AS model, and the zebrafish AS model can be used for high-throughput screening of anti-AS drugs.
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http://dx.doi.org/10.1155/2021/9995401DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8245221PMC
June 2021

Comparative Studies on the Structure-Performance Relationships of Phenothiazine-Based Organic Dyes for Dye-Sensitized Solar Cells.

ACS Omega 2021 Mar 4;6(10):6817-6823. Epub 2021 Mar 4.

Guangxi Key Laboratory of Electrochemical and Magneto-chemical Functional Materials, College of Chemistry and Bioengineering, Guilin University of Technology, Guilin 541004, China.

A D-A-π-A dye () has been synthesized by introducing a benzothiadiazole (BTD) unit as an auxiliary acceptor in a phenothiazine-based D-π-A dye() to broaden its spectral response range and improve the device performance. Photophysical properties indicate that the inclusion of BTD in the effectively red-shifted the absorption spectra by reducing the . However, the device measurements show that the open-circuit voltage ( ) of cell (640 mV) is obviously lower than that of the cell (710 mV). This results in a poor photoelectric conversion efficiency (PCE) (4.43%) compared to that of cell (5.53%). Through further comparative analysis, we found that the introduction of BTD increases the dihedral angle between the D and A unit, which can reduce the efficiency of intramolecular charge transfer (ICT), lead to a less and lower molar extinction coefficient of . In addition, the ESI test found that the lifetime of the electrons in the cell is shorter. These are the main factors for the above unexpected result of PCE. Our studies bring new insights into the development of phenothiazine-based highly efficient dye-sensitized solar cells (DSSCs).
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http://dx.doi.org/10.1021/acsomega.0c05887DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7970489PMC
March 2021

Driver-passenger communicative stress and psychological distress among Chinese bus drivers: the mediating effect of job burnout.

BMC Public Health 2021 03 20;21(1):547. Epub 2021 Mar 20.

Department of Nautical psychology, Faculty of Psychology, The Second Military Medical University, Shanghai, China.

Background: This study aimed to investigate the relationship between driver-passenger communicative stress and psychological distress among bus drivers, as well as whether job burnout mediates the effect of driver-passenger communicative stress on psychological distress.

Methods: A questionnaire consisting of a 12-item version of the General Health Questionnaire (GHQ-12), a one-item driver-passenger communicative stress scale, the Maslach Burnout Inventory-General Survey (MBI-GS), as well as sociodemographic and work factors, was distributed to 310 bus drivers in Shanghai, of which 307 completed it (99.0% response rate). A parallel multiple mediation model with bootstrap approach, was calculated to test the mediating effect.

Results: Driver-passenger communicative stress, emotional exhaustion and cynicism were positively associated with psychological distress. Communicative stress was significantly positively linked with two of the three dimensions of burnout (emotional exhaustion and cynicism) and dependent variable. Emotional exhaustion and cynicism were positively associated with the dependent variable. The results indicate that emotional exhaustion and cynicism partially mediated the effect of communicative stress on psychological health, and that 60.0% of this effect can be explained by mediating effects, in which emotional exhaustion and cynicism weighed 63.2% and 36.8%, respectively.

Conclusions: Communicative stress had effects on psychological distress among Chinese bus drivers, and job burnout was a mediator in this relationship.
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http://dx.doi.org/10.1186/s12889-021-10618-xDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7980616PMC
March 2021

Dandelion extract relaxes mouse airway smooth muscle by blocking VDLCC and NSCC channels.

Cell Biosci 2020 28;10:125. Epub 2020 Oct 28.

School of Pharmaceutical Sciences, South-Central University for Nationalities, 182 Min-Zu Road, Wuhan, 430074 China.

Background: Asthma is one of the main intractable diseases recognized by the international medical community. The current widely used bronchodilators for asthma-β2-adrenal receptor agonists-have limited therapeutic effects, necessitating the development of novel antiasthma drugs with increased efficacy and fewer adverse effects. In this study, we investigated the relaxant effects and underlying mechanism of an ethyl acetate extract from dandelion (EAED) on mouse airway smooth muscle.

Methods: The effects of EAED on agonist-induced precontraction in mouse airway smooth muscle were evaluated with force measurement. Mouse lung slices were used to study the effects of EAED on bronchial smooth muscle. The intracellular Ca concentration was measured using a calcium imaging system. L-type voltage-dependent calcium channel (VDLCC) and non-selective cationic channel (NSCC) currents were measured by patch-clamp. The lung functions of healthy and asthmatic mouse groups were assessed via the forced oscillation technique.

Results: EAED inhibits acetylcholine-induced sustained contractions of whole airway smooth muscle by inhibiting VDLCCs, NSCCs, and some unknown channels, reduces the agonist-induced increase in the cytosolic free Ca concentration in airway smooth muscle cells, blocks VDLCC and NSCC currents, and relieves the respiratory resistance of healthy and asthmatic mice.

Conclusions: EAED may have potential beneficial effects on mitigating asthma attacks.
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http://dx.doi.org/10.1186/s13578-020-00470-8DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7592536PMC
October 2020

Dynamically Modulating Plasmonic Field by Tuning the Spatial Frequency of Excitation Light.

Nanomaterials (Basel) 2020 Jul 24;10(8). Epub 2020 Jul 24.

Shandong Provincial Engineering and Technical Center of Light Manipulations & Shandong Provincial Key Laboratory of Optics and Photonic Device, College of Physics and Electronics, Shandong Normal University, Jinan 250014, China.

Based on the Fourier transform (FT) of surface plasmon polaritons (SPPs), the relation between the displacement of the plasmonic field and the spatial frequency of the excitation light is theoretically established. The SPPs' field shifts transversally or longitudinally when the spatial frequency components f x or f y are correspondingly changed. The SPPs' focus and vortex field can be precisely located at the desired position by choosing the appropriate spatial frequency. Simulation results are in good agreement with the theoretical analyses. Dynamically tailoring the plasmonic field based on the spatial frequency modulation can find potential applications in microparticle manipulation and angular multiplexed SPP focusing and propagation.
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http://dx.doi.org/10.3390/nano10081449DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7466275PMC
July 2020

In vitro gastric digestion antioxidant and cellular radical scavenging activities of wheat-shiitake noodles.

Food Chem 2020 Nov 3;330:127214. Epub 2020 Jun 3.

Lincoln University, Department of Wine, Food and Molecular Bioscience, New Zealand; Riddet Institute, Palmerston North, New Zealand; Tianjin University of Commerce, Tianjin, China. Electronic address:

A high glycaemic index diet causes a rapid increase in blood sugar level and may lead to chronic metabolic disorders such as obesity and type 2 diabetes. Shiitake is rich in bioactive compounds. Wheat flour noodles were enriched with shiitake (Lentinus edodes) powder (cap, stem, whole) at different levels to investigate the effects of shiitake addition on the nutritional composition, physical and textural properties. In vitro digestion was conducted to determine the glycaemic glucose equivalents and bioaccessibility of antioxidants in digesta. The addition of 15% shiitake stem powder in the noodles resulted in a significant (p < 0.05) decrease in reducing sugars released after in vitro digestion. Digesta also exhibited cellular antioxidant ability on IEC-6 cells after HO-induced oxidative stress. These results show the potential beneficial use of shiitake, especially the stem, as a high-value ingredient to improve the nutritional profile and reduce the glycaemic index of foods.
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http://dx.doi.org/10.1016/j.foodchem.2020.127214DOI Listing
November 2020

Genetic polymorphisms and haplotypes of BRCA1 gene associated with quality of life and survival among patients with non-small-cell lung cancer.

Qual Life Res 2020 Oct 18;29(10):2631-2640. Epub 2020 May 18.

College of Psychology, Navy Medical University, 800 Xiangyin Rd., Shanghai, 200433, China.

Purpose: Quality of life (QoL) and prognosis of lung cancer (LC) patients are poor. Previous studies focused less on the relationship between genetic factors and the QoL of LC patients. The current study is intended to explore the association of SNPs and haplotypes of BRCA1 and the QoL and survival of patients with LC.

Methods: QOL of 291 non-small-cell LC patients was measured by EORTC Core Quality of Life Questionnaire (QLQ-C30) and EORTC Quality of Life Questionnaire-Lung Cancer 13 (QLQ-LC13) before discharge. Three tag SNPs of the BRCA1 gene (rs1799966, rs3737559, rs8067269) were detected using an improved multiplex ligation detection reaction (iMLDR) technique. Haplotype analysis was conducted using the software Haploview 4.2. The patients' survival was followed up every six months until March 2019.

Results: rs8067269 was associated with physical functioning (β = 7.97, p = 0.024) and diarrhea (Odds ratios (OR) 0.32, p = 0.042). rs1799966-rs3737559-rs8067269 haplotype was associated with several domains of QoL, including physical functioning (TCG vs. CCA: β = 6.21, p = 0.010), worse dyspnea (TCG vs. CTA: OR 2.05, p = 0.031) and peripheral neuropathy (TCG vs. CTA: OR 3.91, p = 0.030). BRCA1 rs1799966 CC genotype, rs8067269 AA genotype and CCA haplotype were associated with longer survival time of LC patients (p < 0.05).

Conclusion: SNPs and haplotypes of BRCA1 gene were associated with the QoL and survival of patients with LC. Patients with certain genotypes and haplotypes (i.e., rs8067269 AA genotype, or CCA haplotype) had better QoL and prognosis.
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http://dx.doi.org/10.1007/s11136-020-02509-2DOI Listing
October 2020

Association between early informed diagnosis and survival time in patients with lung cancer.

Psychooncology 2020 05 7;29(5):878-885. Epub 2020 Apr 7.

College of Psychology, The Second Military Medical University, Shanghai, China.

Objective: As a malignant tumor with high mortality, lung cancer (LC) often causes great trauma to patients, and a series of negative emotions and a heavy psychological burden accompanies poor prognosis. Whether or not to inform the patients of their condition has always been a controversial topic in the medical community. This retrospective cohort study investigated the association between early informed diagnosis and survival time in patients with LC.

Methods: A total of 29 825 patients with LC were enrolled between October 2002 and December 2016. The potential factors influencing LC survival were registered, including knowing their cancer diagnosis status, age, gender, pathological type, clinical stage, surgical history, hospital grade, and patient occupation. All participants were followed up every 6 months until June 2017.

Results: In June 2017, 23.1% of the participants still survived. Their median survival time (MST) was 11.20 months (95% confidence interval [CI], 10.98-11.43). Generally, patients that knew their cancer diagnosis had longer MST than those who did not (18.33 months vs 8.77 months, P < .001). By stratified analysis, patients that knew their cancer diagnosis had longer survival time in each subgroup (P < .001, all subgroups). Cox regression analysis showed that knowing their cancer diagnosis was an independent influencing factor for survival in patients with LC (hazard ratio, 0.826; 95% CI, 0.802-0.851; P < .001).

Conclusions: Knowing their cancer diagnosis contributed to longer survival time in patients with LC, providing clear evidence that medical staff and patients' families should fully disclose cancer diagnoses to patients.
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http://dx.doi.org/10.1002/pon.5360DOI Listing
May 2020

Enhanced penetration and anti-psoriatic efficacy of curcumin by improved smartPearls technology with the addition of glycyrrhizic acid.

Int J Pharm 2020 Mar 5;578:119101. Epub 2020 Feb 5.

College of Pharmacy and Medical Technology, Putian University, Fujian, China; Key Laboratory of Pharmaceutical Analysis and Laboratory Medicine (Putian University), Fujian, China.

smartPearls technology is one appropriate method to produce anti-psoriatic curcumin (Cur) topical delivery system. To prevent the sedimentation of loaded silica and release changing over the storage, which are disadvantages of smartPearls production, extra glycyrrhizic acid (GA) was added in classical smartPearls ingredients (active and porous material) to get an improved smartPearls production (Cur-GA-silica). The capacity of Cur-GA-silica to remain the gelation state after mixing with water was superior compared to that of the solid cluster without GA and that of the physical mixture of Cur, GA and silica. The Cur-GA-silica practically contained Cur with 1.68% ± 0.12% and showed significant difference with Cur raw drug powder in kinetic solubilities (4.55 ± 0.78 µg/mL vs 0 in 5 min; 3.26 ± 0.17 µg/mL vs 0 in 4 h) which was traceable to the amorphous state of Cur-GA-silica detected by X-ray diffractometer. With the amorphous Cur, two times as much penetrated Cur in Cur-GA-silica as in Cur raw drug powder was achieved on the imiquimod-induced psoriasis-like mice model. The anti-psoriatic efficacy of Cur-GA-silica was confirmed by Psoriasis Area and Severity Index (PASI) evaluation, histological evaluation and decreased IL-17A in the imiquimod-induced psoriasiform mouse skin analyzed by enzyme-linked immunosorbent assay. In conclusion, with the addition of GA, a stable amorphous curcumin topical vehicle fabricated by smartPearls technology without extra dermal matrix is available and facilitates penetration efficacy and anti-psoriatic capacity in imiquimod-induced psoriasiform mice.
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http://dx.doi.org/10.1016/j.ijpharm.2020.119101DOI Listing
March 2020

Correlation between use of immunosuppressive agents and transplant-acquired allergies in renal transplant recipients.

Transl Androl Urol 2019 Oct;8(5):442-447

Organ Transplantation Center, the Second Affiliated Hospital of Guangzhou Medical University, Guangzhou 511447, China.

Background: Although immunosuppressive agents used in recipients of organ transplants can suppress T cell immune responses, type I allergy to ingested or inhaled allergens after organ transplantation have frequently been reported in pediatric patients. This study aims to investigate the relationship between the use of immunosuppressive agents and the transplant-acquired allergy (TAA) in adult renal transplant recipients (RTRs).

Methods: Seventy-nine RTRs treated in our hospital from February 2015 to February 2016 were interviewed for allergic diseases by using a standard questionnaire. UniCAP allergen screening tests were performed to detect total IgE and specific IgE levels before and after renal transplantation after the use of calcineurin inhibitor tacrolimus (FK506) or cyclosporin A (CsA). The follow-up visits were scheduled for 6 months, 1 year, 2 years, and 3 years after transplantation.

Results: Allergen sensitization occurred in 9 of 79 patients. Among them, the sensitization occurred in 2 cases within 6 months after renal transplantation, in 1 case from 6 months to 1 year, in 3 cases from 1 to 2 years, and in 3 cases from 2 to 3 years. The majority of sensitization was induced by inhaled allergens (n=7), among whom 3 patients (3/79, 3.8%) had a history of type I allergy, which occurred within 6 months after transplantation in 2 cases (allergic dermatitis) and from 2 to 3 years in 1 case (diarrhea after peanut allergy). The total IgE levels of RTRs using immunosuppressive agents at different time points including 6 months, 1 year, 2 years, and 3 years after renal transplantation were significantly lower than that before surgery (all P<0.05). Sensitization occurred in 8 RTRs using FK506 and in 1 patient treated with CsA (P=0.432), and allergies occurred in 3 RTRs using FK506 and were not found among CsA users (P=0.561).

Conclusions: Administration of immunosuppressive agents in adult RTRs cannot wholly prevent allergy or sensitization. Studies with larger sample sizes and more extended follow-up periods are still required to further explore the potential association between the use of FK506 and CSA and the allergies or sensitization.
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http://dx.doi.org/10.21037/tau.2019.09.24DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6842773PMC
October 2019

Protective effect of pterostilbene on concanavalin A-induced acute liver injury.

Food Funct 2019 Nov 18;10(11):7308-7314. Epub 2019 Oct 18.

Tianjin Key Laboratory of Food and Biotechnology, State Experimental and Training Centre of Food and Drug, School of Biotechnology and Food Science, Tianjin University of Commerce, No.409 Guangrong Road, Beichen, Tianjin 300134, China.

Pterostilbene (PTE) is broadly found in berries and has antioxidant and anti-inflammatory properties. To examine the effect of PTE on acute liver injury, mice were administrated PTE prior to concanavalin A (ConA). The mice were divided into the following groups: (i) vehicle control, (ii) ConA alone, (iii) ConA with PTE at 10 mg kg (PTE low dose, PTL), and (iv) ConA with PTE at 40 mg kg (PTE high dose, PTH). After the ConA challenge, the mice showed prompt induction of intrahepatic IFN-γ and TNF-α, followed by tissue factor (TF), which aggravated the fibrin deposition and massive liver necrosis. However, these effects were significantly counteracted by the PTE pretreatment. Furthermore, PTE reversed the phosphorylation of ConA-induced intrahepatic inflammatory kinases including JNK, ERK1/2, p38 and p65. Interestingly, PTE did not directly act on the hepatocytes, but inhibited intrahepatic macrophage accumulation and TF generation by inhibiting the activation of inflammatory p38 MAPK. These results suggest a promising avenue for the exploration of pterostilbene in improving acute liver injury.
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http://dx.doi.org/10.1039/c9fo01405eDOI Listing
November 2019

Potential association between exposure to legacy persistent organic pollutants and parasitic body burdens in Indo-Pacific finless porpoises from the Pearl River Estuary, China.

Sci Total Environ 2018 Dec 27;643:785-792. Epub 2018 Jun 27.

Zhuhai Key Laboratory of Marine Bioresources and Environment, Guangdong Provincial Key Laboratory of Marine Resources and Coastal Engineering, School of Marine Sciences, Sun Yat-Sen University, Zhuhai 519000, China. Electronic address:

A high prevalence of infectious diseases (mostly lungworms) is found in finless porpoises (genus Neophocaena) in the coastal waters of China, which is one of the most dichlorodiphenyltrichloroethane (DDT)-polluted areas worldwide, while its association with contaminant exposure remains undetermined. To address this gap, we investigated blubber levels of polychlorinated diphenyls (PCBs), organochlorine pesticides (OCPs) and polycyclic aromatic hydrocarbons in Indo-Pacific finless porpoises (Neophocaena phocaenoides) stranded in the Pearl River Estuary (PRE) of China. In the post-mortem examinations, lungworms (Halocercus species) were found to be the most common parasites, with a high density observed in lungs and bronchi. Severe infections by nematode parasites were also found in the uterus (Cystidicola species), intestine (Anisakis typica) and muscle (A. typica). For all the pollutant compounds analyzed, only the concentrations of p,p'-DDT, p,p'-dichlorodiphenyldichloroethane (DDD) and o,p'-DDD were significantly higher in porpoises died of infectious diseases than in the "healthy" individuals (died from physical trauma). Contrasted accumulation pattern of DDTs and their metabolites was found between animals with different health status. The proportion of p,p'-DDT in ΣDDTs was higher than that of p,p'-dichlorodiphenyldichloroethylene (DDE) in diseased animals, whereas an opposite pattern was shown for "healthy" ones. While this study is the first to describe a significant positive correlation between parasitic diseases and high levels of DDTs in cetaceans, the direction of causality cannot be determined in our data: either a parasitic infection affected the porpoises' ability to metabolize DDTs, resulting in high levels of p,p'-DDT in their blubber, or the pollutant burden rendered them more susceptible to parasitic infection.
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http://dx.doi.org/10.1016/j.scitotenv.2018.06.249DOI Listing
December 2018

High-efficiency terahertz devices based on cross-polarization converter.

Sci Rep 2017 12 20;7(1):17882. Epub 2017 Dec 20.

Department of Physics, Capital Normal University, Beijing Key Laboratory of Metamaterials and Devices, Key Laboratory of Terahertz Optoelectronics, Ministry of Education, and Beijing Advanced Innovation Center for Imaging Technology, Beijing, 100048, P. R. China.

Metasurface-based devices have been investigated intensively because of their attractive properties but these devices generally suffer from low efficiency. Here we demonstrate several high-efficiency terahertz (THz) devices based on cross-polarization converters that is composed of bilayer metasurface-based structures. The converter can transfer the polarization states of transmitted THz waves from the x-direction into the y-direction with an experimental conversion efficiency of 85%. This high-efficiency transfer mechanism is investigated in detail. Furthermore, this kind of devices can be fabricated easily. A THz metalens is designed and fabricated and its focusing and imaging properties are investigated experimentally. A pure phase THz hologram that can generate different images on different propagation planes is also designed and the image reconstruction capabilities of the phase holograms are demonstrated experimentally. The performance levels of all designed devices show excellent agreement between the theoretical expectations and the corresponding experimental results. This technology may pave the way towards practical applications of such metasurface devices.
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http://dx.doi.org/10.1038/s41598-017-18013-6DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5738362PMC
December 2017

Wavelength de-multiplexing metasurface hologram.

Sci Rep 2016 10 18;6:35657. Epub 2016 Oct 18.

Department of Physics, Capital Normal University, Beijing Key Laboratory of Metamaterials and Devices, Key Laboratory of Terahertz Optoelectronics, Ministry of Education, and Beijing Advanced Innovation Center for Imaging Technology, Beijing, 100048, China.

A wavelength de-multiplexing metasurface hologram composed of subwavelength metallic antennas is designed and demonstrated experimentally in the terahertz (THz) regime. Different character patterns are generated at the separated working frequencies 0.50 THz and 0.63 THz which determine a narrow frequency bandwidth of 130 GHz. The two working frequencies are around the central resonance frequency of the antennas where antennas behave strong wavefront modulation. Each antenna is fully utilized to control the wavefront of the metasurface at different frequencies by an optimization algorithm. The results demonstrate a candidate way to design multi-colors optical display elements.
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http://dx.doi.org/10.1038/srep35657DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5067676PMC
October 2016

A broadband terahertz ultrathin multi-focus lens.

Sci Rep 2016 06 27;6:28800. Epub 2016 Jun 27.

Department of Physics, Harbin Institute of Technology, Harbin, 150001, P.R. China.

Ultrathin transmission metasurface devices are designed on the basis of the Yang-Gu amplitude-phase retrieval algorithm for focusing the terahertz (THz) radiation into four or nine spots with focal spacing of 2 or 3 mm at a frequency of 0.8 THz. The focal properties are experimentally investigated in detail, and the results agree well with the theoretical expectations. The designed THz multi-focus lens (TMFL) demonstrates a good focusing function over a broad frequency range from 0.3 to 1.1 THz. As a transmission-type device based on metasurface, the diffraction efficiency of the TMFL can be as high as 33.92% at the designed frequency. The imaging function of the TMFL is also demonstrated experimentally and clear images are obtained. The proposed method produces an ultrathin, low-cost, and broadband multi-focus lens for THz-band application.
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http://dx.doi.org/10.1038/srep28800DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4921809PMC
June 2016

Abruptly autofocusing terahertz waves with meta-hologram.

Opt Lett 2016 Jun;41(12):2787-90

An abruptly autofocusing ring-Airy beam is demonstrated in the terahertz (THz) waveband with a meta-hologram. The designed meta-hologram is composed of gold C-shaped slot antennas, which can realize both phase and amplitude modulation of the incident THz wave. A THz holographic imaging system is utilized to measure the generated ring-Airy beam; an abrupt focus following a parabolic trajectory is subsequently observed. THz ring-Airy beams with different parameters are also generated and investigated. This method can be expanded to other wavebands, such as the visible band, for which the meta-hologram can replace traditional computer-generated holography to avoid undesirable multiple diffraction orders.
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http://dx.doi.org/10.1364/OL.41.002787DOI Listing
June 2016

Exciton localization in solution-processed organolead trihalide perovskites.

Nat Commun 2016 Mar 21;7:10896. Epub 2016 Mar 21.

State Key Laboratory of Silicon Materials, School of Materials Science and Engineering, Zhejiang University, Hangzhou 310027, China.

Organolead trihalide perovskites have attracted great attention due to the stunning advances in both photovoltaic and light-emitting devices. However, the photophysical properties, especially the recombination dynamics of photogenerated carriers, of this class of materials are controversial. Here we report that under an excitation level close to the working regime of solar cells, the recombination of photogenerated carriers in solution-processed methylammonium-lead-halide films is dominated by excitons weakly localized in band tail states. This scenario is evidenced by experiments of spectral-dependent luminescence decay, excitation density-dependent luminescence and frequency-dependent terahertz photoconductivity. The exciton localization effect is found to be general for several solution-processed hybrid perovskite films prepared by different methods. Our results provide insights into the charge transport and recombination mechanism in perovskite films and help to unravel their potential for high-performance optoelectronic devices.
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http://dx.doi.org/10.1038/ncomms10896DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4802114PMC
March 2016

An Analog of electrically induced transparency via surface delocalized modes.

Sci Rep 2015 Jul 21;5:12251. Epub 2015 Jul 21.

Department of Physics, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong.

We demonstrate theoretically and experimentally an interesting opaque state, which is based on an analog of electromagnetically induced transparency (EIT) in mechanism, in a metal hole array of the dimer lattice. By introducing a small difference to the dimer holes of each unit cell, the surface delocalized modes launching out from the dimer holes can have destructive interferences. Consequently, a narrow opaque window in the transparent background can be observed in the transmission spectrum. This surface-mode-induced opacity (SMIO) state is very sensitive to the difference of the dimer holes, which will promise various applications.
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http://dx.doi.org/10.1038/srep12251DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4508561PMC
July 2015

Generation of terahertz vector beams with a concentric ring metal grating and photo-generated carriers.

Opt Lett 2015 Feb;40(3):359-62

A scheme for vector terahertz (THz) beam generation is proposed. A subwavelength metal grating is utilized to adjust the polarization of the THz radiation. The amplitude and phase distributions of the THz beam are dynamically regulated by a THz computer-generated hologram (CGH) pattern of the photo-generated carriers. A radially polarized THz beam and a vector THz vortex beam with a topological charge of 1 are generated to demonstrate the validity and the effectiveness of the proposed scheme. Experimental results correspond to the theoretical simulations well. Moreover, the proposed method is applicative for a broadband THz radiation. These results could be applied in the THz sensing, THz imaging, and THz communication in the future.
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http://dx.doi.org/10.1364/OL.40.000359DOI Listing
February 2015

Generation and evolution of the terahertz vortex beam.

Opt Express 2013 Aug;21(17):20230-9

Based on the complementary V-shaped antenna structure, ultrathin vortex phase plates are designed to achieve the terahertz (THz) optical vortices with different topological charges. Utilizing a THz holographic imaging system, the two dimensional complex field information of the generated THz vortex beam with the topological number l=1 is directly obtained. Its far field propagation properties are analyzed in detail, including the rotation, the twist direction, and the Gouy phase shift of the vortex phase. An analytic Laguerre-Gaussian mode is used to simulate and explain the measured phenomena. The experimental and simulation results overlap each other very well.
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http://dx.doi.org/10.1364/OE.21.020230DOI Listing
August 2013
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