bluuebunny/crossref_metadata_2025 huggingface dataset:
COVID-19: is there a role for immunonutrition, particularly in the over 65s?
Authors: Derbyshire Emma , Delange Joanne
Published: April 2020

In late December 2019 severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) first emerged in Wuhan, Hubei, China, resulting in the potentially fatal COVID-19. It went on to be officially recognised as a pandemic by the World Health Organisation on 11 March 2020. While many public health strategies have evolved, there has been little mention of the immune system and how this could be strengthened to help protect against viral infections such as SARS-CoV-2. The present paper evaluates the current evidence base relating to immunonutrition, with a particular focus on respiratory viruses. Within the nutrition sector a promising body of evidence studying inter-relationships between certain nutrients and immune competence already exists. This could potentially be an important player in helping the body to deal with the coronavirus, especially among elders. Evidence for vitamins C, D and zinc and their roles in preventing pneumonia and respiratory infections (vitamins C and D) and reinforcing immunity (zinc) appears to look particularly promising. Ongoing research within this important field is urgently needed.
Influence of culture, religion and experience on the decision of Pakistani women in Lothian, Scotland to use postnatal contraception: a qualitative study
Authors: Gallimore Annette , Irshad Tasneem , Cooper Michelle , Cameron Sharon
Published: April 2020

Introduction

Evidence suggests that Pakistani women may experience difficulty accessing postnatal contraceptive (PNC) services. The study aimed to identify experience and decision-making around PNC provision for Pakistani women in Lothian, and to explore the views and experience of maternity staff who provide PNC counselling.

Methods

Qualitative research including focus groups and 1:1 semi-structured interviews with women and staff. Participants were first- and second-generation Pakistani women with a child/children aged up to 5 years, or pregnant; community and hospital midwives, obstetric doctors who counsel or provide PNC. Data were coded and categorised using QSR NVIVO10. Inductive thematic analysis was carried out.

Results

Women were receptive to discussion of contraception, including antenatally, and welcomed translated information. Some said the decision on PNC was theirs or made jointly with their husband; however, they acknowledged that in some marriages the husband will take the decision. Women stated they may face family expectation to have a baby early in marriage. Language was identified as a challenge by maternity staff, who utilised translation services to ensure women received the information they needed on contraception.

Conclusions

Pakistani women value antenatal discussion about PNC. Maternity staff have an important role in providing quality information on contraception and should be supported with translated resources in a range of formats. Most importantly, staff should adopt a tailored approach to identify the individual woman’s needs and preferences.
Cerebral small vessel disease or intracranial large vessel atherosclerosis may carry different risk for future strokes
Authors: Chen Huimin , Pan Yuesong , Zong Lixia , Jing Jing , Meng Xia , Xu Yuyuan , Yan Hongyi , Zhao Xingquan , Liu Liping , Li Hao , Johnston S Claiborne , Wang Yongjun , Wang Yilong
Published: April 2020

Background

The effect of cerebral small vessel disease (CSVD) and intracranial arterial stenosis (ICAS) on stroke outcomes remains unclear.

Methods

Data of 1045 patients with minor stroke or transient ischaemic attack (TIA) were obtained from 45 sites of the Clopidogrel in High-Risk Patients with Acute Non-disabling Cerebrovascular Events (CHANCE) trial. We assessed the associations of burdens of CSVD and ICAS with new strokes and bleeding events using multivariate Cox regression models and those with modified Rankin Scale (mRS) scores using ordinal logistic regression models.

Results

Among the 1045 patients, CSVD was present in 830 cases (79.4%) and ICAS in 460 (44.0%). Patients with >1 ICAS segment showed the highest risk of new strokes (HR 2.03, 95% CI 1.15 to 3.56, p=0.01). No association between CSVD and the occurrence of new strokes was found. The presence of severe CSVD (common OR (cOR) 2.01, 95% CI 1.40 to 2.89, p<0.001) and >1 ICAS segment (cOR 2.15, 95% CI 1.57 to 2.93, p<0.001) was associated with higher mRS scores. Severe CSVD (HR 10.70, 95% CI 1.16 to 99.04, p=0.04), but not ICAS, was associated with a higher risk of bleeding events. Six-point modified CSVD score improved the predictive power for bleeding events and disability.

Interpretation

CSVD is associated with more disability and bleeding events, and ICAS is associated with an increased risk of stroke and disability in patients with minor stroke and TIA at 3 months. CSVD and ICAS may represent different vascular pathologies and play distinct roles in stroke outcomes.

Trial registration number

NCT00979589
Minimally invasive osteosynthesis of a distal humeral Salter‐Harris type II fracture by percutaneous pinning
Authors: Hartman Emily A , Perry Karen Lisette , Dejardin Loic M
Published: April 2020

A 13.2‐kg, skeletally immature German shepherd dog presented with acute onset non–weight‐bearing right forelimb lameness. A mildly displaced, distal humeral Salter‐Harris type II fracture was diagnosed using radiographs and CT scan which demonstrated a characteristic ‘corner’ sign. Closed reduction was achieved using ligamentotaxis techniques and stabilisation was performed via percutaneous pinning under fluoroscopic guidance. Physical examination and diagnostic imaging were repeated at 1 month postoperatively with telephone communication and Canine Brief Pain Inventory being completed 12 months postoperatively. Clinical union was documented radiographically 4 weeks postoperatively. Minimal lameness was noted clinically, reported to have resolved 2 weeks thereafter. Long‐term outcome was excellent with both pain severity score and pain interference score being zero. This is the first detailed report of a distal humeral Salter‐Harris type II fracture in the veterinary literature. Principles of minimally invasive osteosynthesis were applied to achieve closed reduction and stabilisation with excellent long‐term clinical outcome.
Accidental arterial catheterisation during a maxillary nerve block using a modified infraorbital approach in a dog
Authors: McCarthy Paul Massimo Giannoni , Chau Arthur Yuk Kong
Published: April 2020

The maxillary nerve block (MNB) is a local anaesthetic technique used in dentistry and oromaxillofacial surgery, with recent popular use for minimising adverse reactions during rhinoscopy. A modified approach via the infraorbital foramen using an intravenous catheter has been recently described in the veterinary literature to minimise potential nerve block associated complications. This case report describes inadvertent arterial catheterisation using the aforementioned technique in a 5.4‐kg, 9‐year‐old male neutered Maltese terrier cross that was presented for diagnostic workup of a chronic cough that had recently worsened. To the authors’ knowledge, this is the first case report of such a complication. It is recommended for veterinary practitioners to be aware of accidental arterial puncture and catheterisation whenever a modified infraorbital approach to the MNB is performed in order to facilitate rapid intervention and management.
MicroRNA-518-3p suppresses cell proliferation, invasiveness, and migration in colorectal cancer via targeting TRIP4
Authors: Yang Heng , Ren Jia , Bai Yu , Jiang Jielin , Xiao Shiyao
Published: April 2020

MicroRNA (miR)-518-3p has been shown to function as a tumor suppressor. This study was conducted to investigate the effects of miR-518-3p in colorectal cancer (CRC). The miR-518-3p mimic, mimic negative control (NC), miR-518-3p inhibitor, inhibitor-NC, ShRNA-TRIP4, and ShRNA-NC vectors were transfected into SW480 cells using Lipofectamine 2000. Cell viability was detected using CCK-8. Colony formation, cell invasiveness, and cell migration were assessed by plate colony formation, Transwell assays, and wound healing assays, respectively. Relative mRNA and protein levels were detected using RT–qPCR and Western blot, respectively. The target gene thyroid hormone receptor interactor 4 (TRIP4) of miR-518-3p was identified and further verified using dual-luciferase reporter assay. Compared with normal tissues, levels of miR-518-3p were decreased and TRIP4 was significantly increased in the tissues from patients with CRC. Following transfection with a miR-518-3p mimic or ShRNA-TRIP4, cell viability decreased in a time-dependent manner, and colony formation rate, wound closure rate, and the number of invasive cells were much lower for the transfected cells than in the corresponding NC and control groups. miR-518-3p overexpression or silencing of TRIP4 significantly down-regulated the expression of MMP-2 and MMP-9. Knockdown of miR-518-3p had the opposite effects, and TRIP4 was identified as a target of miR-518-3p. The inhibitory effects of miR-518-3p on the progressions of CRC are associated with TRIP4.
Linear energy transfer dependence of transient yields in water irradiated by 150 keV – 500 MeV protons in the limit of low dose rates
Authors: Alanazi Ahmed , Meesungnoen Jintana , Jay-Gerin Jean-Paul
Published: April 2020

FLASH radiotherapy is a new irradiation method in which large doses of ionizing radiation are delivered to tumors almost instantly (a few milliseconds), paradoxically sparing healthy tissue while preserving anti-tumor activity. Although this technique is primarily studied in the context of electron and photon therapies, proton delivery at high dose rates can also reduce the adverse side effects on normal cells. So far, no definitive mechanism has been proposed to explain the differences in the responses to radiation between tumor and normal tissues. Given that living cells and tissues consist mainly of water, we set out to study the effects of high dose rates on the radiolysis of water by protons in the energy range of 150 keV – 500 MeV (i.e., for linear energy transfer (LET) values between ∼72.2 and 0.23 keV/μm, respectively) using Monte Carlo simulations. To validate our methodology, however, we, first, report here the results of our calculations of the yields (G values) of the radiolytically produced species, namely the hydrated electron ([Formula: see text]), •OH, H•, H2, and H2O2, for low dose rates. Overall, our simulations agree very well with the experiment. In the presence of oxygen, [Formula: see text] and H• atoms are rapidly converted into superoxide anion or hydroperoxyl radicals, with a well-defined maximum of [Formula: see text] at ∼1 μs. This maximum decreases substantially when going from low-LET 500 MeV to high-LET 150 keV irradiating protons. Differences in the geometry of the proton track structure with increasing LET readily explain this diminution in [Formula: see text] radicals.
Knockdown of Matrix Metallopeptidase 9 Inhibits Metastasis of Oral Squamous Cell Carcinoma Cells in a Zebrafish Xenograft Model
Authors: Wen Jinlin , Yin Panpan , Li Linwei , Kang Guihua , Ning Guozhu , Cao Yu , Gao Feng , Su Ying , Wu Yanlin , Zhang Xinyan
Published: April 2020

Destruction of extracellular matrix (ECM) is one of the basic steps of tumor invasion and metastasis. Matrix metalloproteinase (MMP) 9, a kind of zinc‐ion‐dependent endopeptidase, can degrade almost all protein components in the ECM, destroy the histological barrier of tumor cell invasion, and play a key role in tumor invasion and metastasis. The role of MMP‐9 in tumor invasion and metastasis has attracted increasing attention and is considered the main proteolytic enzyme in this process. Although the overexpression of MMP‐9 was detected in Oral squamous cell carcinoma (OSCC) tissues, further basic studies in vivo and in vitro are needed to investigate the role of MMP‐9 in OSCCs and provide scientific validation. In this research, we developed a novel OSCC zebrafish xenograft model to study the role of the MMP‐9 gene in oral carcinogenesis. Firstly, the MMP‐9/shRNA lentiviral clone and control virus were constructed and transfected into OSCC cells. Then, the decreasing expression of MMP‐9 was verified by RT‐PCR and immunocytochemistry. Cell proliferation was detected by MTT assay. Colony formation was evaluated by colony formation assay. Cell invasion was evaluated using transwell invasion assay in vitro. In addition, OSCC cells with MMP‐9/shRNA knockdown and control vector were injected into zebrafish and an OSCC tumor model in zebrafish was established to evaluate invasion and metastasis in vivo. Knockdown of MMP‐9 gene by shRNA could inhibit OSCC cell growth and clone formation and markedly suppress cell invasion in vitro. And the knockdown of the MMP‐9 gene could also significantly decrease the metastatic distance and number of metastatic tumor cells or lesions in vivo and suppress the metastasis rate in xenografted zebrafish. Taken together, these evidences indicated that the knockdown of MMP‐9 might suppress OSCC cell invasion and metastasis in vivo and in vitro. The MMP‐9 gene may be a promising therapeutic target for OSCCs in the future.
Morphological and Transcriptome Analyses Provide Insights into Growth Inhibition of Trichophyton rubrum Caused by Laser Irradiation
Authors: Zhang Rui-Na , Zhao Jun-Ying , Li Lin-Feng
Published: April 2020

Trichophyton rubrum is one of the most common types of dermatophyte, causing superficial skin mycosis in human populations. Although laser treatment of onychomycosis has been proven to be effective in the clinic, the underlying mechanism of the effect of the laser on fungal growth is not clear. The objective of the present study was to observe the ultrastructural changes of Trichophyton rubrum following laser irradiation and compare the transcriptome differences between the laser irradiation group and control group. In the present study, scanning electron microscopy and transmission electron microscopy were used to observe the ultrastructural changes following the laser irradiation of Trichophyton rubrum. We also performed RNA‐seq to investigate the effects of laser irradiation on Trichophyton rubrum by comparing the transcriptome pattern with the control. Morphological observation with electron microscopy indicated that laser irradiation resulted in the destruction of the cell membrane system. A significant induction of apoptosis was noted compared with the control group, which was confirmed by the formation of the myeloid body and protein aggregates in the cytoplasm. RNA‐seq demonstrated that the expression levels of Acyl‐CoA N‐acyltransferase and S‐adenosyl‐L‐methionine‐dependent methyltransferase were increased in the laser irradiation group. This result indicated that laser irradiation triggered the initiation of the damage repair pathway. In conclusion, the present study suggested that laser irradiation caused physiological injury and therefore inhibited the growth of Trichophyton rubrum.
Experimental and Optimization Study on the Sliding Force Monitoring and Early Warning System for High and Steep Slopes
Authors: Wang Ligang , Tao ZhiGang , He ManChao , Yang Xiaocong
Published: April 2020

A series of high and steep slopes have been formed due to the deep exploitation of resources in open‐pit mines across China. The stability of these high and steep slopes has become an essential factor affecting the efficient, safe, and sustainable development of deep mineral resources. Due to numerous problems such as constant resistance fluctuation and pipe jamming of the original sliding force monitoring system, leading to system failure, a series of improvements on the current monitoring systems were implemented. This specific work included a mechanical characteristics test of the anchor cable, improvement of the constant resistance structure, and measurement of the internal displacement of the slope. The communication mode and the software architecture of the system were also adjusted. This work significantly improved the overall performance of the sliding force monitoring and early warning system. The improvements performed in this research are systematically described to provide an example of good practice for other sites with similar features. The collected data show that the improved sliding force monitoring system can accurately reflect the whole process of landslide incubation. Moreover, the validity of the early warning criterion based on the sliding force is verified again using the field test.
Limb Ischemic Postconditioning Alleviates Postcardiac Arrest Syndrome through the Inhibition of Mitochondrial Permeability Transition Pore Opening in a Porcine Model
Authors: Wang Zhengquan , Wu Lifeng , Xu Jiefeng , Gao Jindan , Ye Sen , Li Zilong , Chen Yuanzhuo , Zhang Xiangyu
Published: April 2020

Objective. Previously, the opening of mitochondrial permeability transition pore (mPTP) was confirmed to play a key role in the pathophysiology of postcardiac arrest syndrome (PCAS). Recently, we demonstrated that limb ischemic postconditioning (LIpostC) alleviated cardiac and cerebral injuries after cardiac arrest and resuscitation. In this study, we investigated whether LIpostC would alleviate the severity of PCAS through inhibiting mPTP opening. Methods. Twenty‐four male domestic pigs weighing 37 ± 2 kg were randomly divided into three groups: control, LIpostC, and LIpostC+atractyloside (Atr, the mPTP opener). Atr (10 mg/kg) was intravenously injected 30 mins prior to the induction of cardiac arrest. The animals were subjected to 10 mins of untreated ventricular fibrillation and 5 mins of cardiopulmonary resuscitation. Coincident with the beginning of cardiopulmonary resuscitation, LIpostC was induced by four cycles of 5 mins of limb ischemia and then 5 mins of reperfusion. The resuscitated animals were monitored for 4 hrs and observed for an additional 68 hrs. Results. After resuscitation, systemic inflammation and multiple organ injuries were observed in all resuscitated animals. However, postresuscitation systemic inflammation was significantly milder in the LIpostC group than in the control group. Myocardial, lung, and brain injuries after resuscitation were significantly improved in the LIpostC group compared to the control group. Nevertheless, pretreatment with Atr abolished all the protective effects induced by LIpostC. Conclusion. LIpostC significantly alleviated the severity of PCAS, in which the protective mechanism was associated with the inhibition of mPTP opening.
Preeclampsia and the Ten-Year Risk of Incident Chronic Kidney Disease
Authors: Behboudi-Gandevani Samira , Amiri Mina , Rahmati Maryam , Amanollahi Soudmand Saber , Azizi Fereidoun , Ramezani Tehrani Fahimeh
Published: April 2020

Background: Although preeclampsia (PE), as an endothelial disorder can lead to renal dysfunction during pregnancy, results of studies focusing on the potential long-term potential effects of PE on renal function are insufficient and those available are controversial. This study investigated the incidence rate and risk of chronic kidney disease (CKD) among women with prior history of PE compared with healthy controls in a long-term population-based study. Methods: This was a prospective population-based cohort study. Subjects were 1,851 eligible women, aged 20–50 years, with at least 1 pregnancy (177 women with prior-PE and 1,674 non-PE controls) selected from among the Tehran-Lipid and Glucose-Study-participants. A pooled-logistic-regression-model and Cox’s-proportional-hazards-models were utilized to estimate the risk of CKD in women of both PE and without PE groups, after further adjustment for confounders. Results: Median and interquartile ranges for follow-up durations of the PE and non-PE groups were 7.78 (5.19–10.40) and 7.32 (4.73–11.00) years, respectively. Total cumulative incidence rates of CKD at the median follow-up time of each group were 35/100,000 (95% CI 25/100,000–50/100,000) and 36/100,000 (95% CI 32/100,000–39/100,000) in PE and non-PE women, respectively (p value = 0.90). Based on pooled-logistic-regression-analysis, OR of CKD progression (adjusted for age, body mass index [BMI], systolic blood pressure [SBP], and diastolic blood pressure [DBP]) for the PE group did not differ, compared to their non-PE counterparts (OR 1.04; p value = 0.80; 95% CI 0.77–1.40). Compared to non-PE women, women with prior PE did not have higher hazard ratios (HRs) of developing CKD in the unadjusted model (unadjusted HR 1.1, 95% CI 0.83–1.69, p = 0.35), results which remained unchanged after adjustment for age, BMI, baseline SBP, and DBP. Conclusion: PE was not found to be a risk factor for CKD. More studies using a prospective cohort design with long-term follow-ups are needed to investigate the relationship between preeclamsia and CKD.
Induction of Oral Tolerance by Pepsin-Digested Gliadin Retaining T Cell Reactivity in a Mouse Model of Wheat Allergy
Authors: Li Xuyang , Miyakawa Takuya , Takano Tomohiro , Nakajima-Adachi Haruyo , Tanokura Masaru , Hachimura Satoshi
Published: April 2020

Background: Wheat is known as the most widely consumed food all over the world. Although many types of wheat allergy have been recognized, their treatment still has a long way to go due to the complex pathogenesis. Oral immunotherapy (OIT) is under investigation for the treatment of wheat allergies. Previous studies have demonstrated that OIT using intact wheat allergens can induce tolerance, but is accompanied by a high risk of anaphylactic reactions. Objectives: Our objective was to prepare modified wheat allergens with hypoallergenic and tolerance-inducing properties to reduce adverse effects during immunotherapy. Methods: Wheat gliadin was degraded by hydrolysis with pepsin and trypsin, and then the hydrolysate was deamidated with hydrochloric acid. The IgE-binding capacity and T cell reactivity of the degraded gliadins were evaluated in vitro. Pepsin-digested gliadin (peptic-GLI) was applied in a mouse model to investigate whether it would induce oral tolerance. Results: Degradation with pepsin decreased IgE-binding capacity and maintained T cell reactivity. Oral administration of peptic-GLI to mice before sensitization and challenge with gliadin could significantly suppress the production of IgE, IgG1, and type 2 T helper cytokines. Moreover, the development of anaphylactic reactions and allergic responses of the small intestine induced by gliadin challenge were inhibited by oral administration of peptic-GLI. Conclusions: The findings of this study indicate that peptic-GLI with low allergenicity and potential for tolerance induction may become useful in wheat immunotherapy with less adverse effects.
Pharmacological Acromegaly Treatment: Cost-Utility and Value of Information Analysis
Authors: Leonart Leticia P. , Riveros Bruno S. , Krahn Murray D. , Pontarolo Roberto
Published: April 2020

Objectives: To conduct a cost-utility analysis comparing drug strategies involving octreotide, lanreotide, pasireotide, and pegvisomant for the treatment of patients with acromegaly who have failed surgery, from a Brazilian public payer perspective. Methods: A probabilistic cohort Markov model was developed. One-year cycles were employed. The patients started at 45 years of age and were followed lifelong. Costs, efficacy, and quality of life parameters were retrieved from the literature. A discount rate (5%) was applied to both costs and efficacy. The results were reported as costs per quality-adjusted life year (QALY), and incremental cost-effectiveness ratios (ICERs) were calculated when applicable. Scenario analyses considered alternative dosages, discount rate, tax exemption, and continued use of treatment despite lack of response. Value of information (VOI) analysis was conducted to explore uncertainty and to estimate the costs to be spent in future research. Results: Only lanreotide showed an ICER reasonable for having its use considered in clinical practice (R$ 112,138/US$ 28,389 per QALY compared to no treatment). Scenario analyses corroborated the base-case result. VOI analysis showed that much uncertainty surrounds the parameters, and future clinical research should cost less than R$ 43,230,000/US$ 10,944,304 per year. VOI also showed that almost all uncertainty that precludes an optimal strategy choice involves quality of life. Conclusions: With current information, the only strategy that can be considered cost-effective in Brazil is lanreotide treatment. No second-line treatment is recommended. Significant uncertainty of parameters impairs optimal decision-making, and this conclusion can be generalized to other countries. Future research should focus on acquiring utility data.
Anmerkungen zur Etymologie von ahd. sahar ‚Segge‘
Authors: Schuhmann Roland
Published: April 2020

In the etymological literature there exist two divergent reconstructions for the word group around OHG sahar ‘sedge’: PGmc. *saχaza- and *saχ(a)ra-. Of these two the former is nearly exclusively found in Indo-European literature. The reconstruction *saχaza- cannot be correct. This is obvious because of the forms found in the Romanic languages, that were borrowed from Gothic, a language that did not undergo rhotazism. The neglect of literature from the field of Romance Studies is therefore accountable for the persistence of a false reconstruction in Indo-European studies.
Some Phonological Developments in the Malberg Glosses
Authors: van Doorn Adriaan
Published: April 2020

The language of the Malberg glosses shows phonological developments that allow us to position this language variety within the West-Germanic dialect continuum. In this article the author shows that the language cannot be viewed as Old Dutch, nor as the ancestor of Old Dutch based on the attested phonological developments, notably: the assimilation of certain clusters; the partial merger of Proto-Germanic *g and *h; and the palatalisation of Proto-Germanic *g.
Nanoassembly of meso-Tetraphenylporphines on Surfaces of Carbon Materials: Initial Steps as Studied by Molecular Mechanics and Scanning Tunneling Microscopy
Authors: Basiuk Vladimir A. , Bassiouk Maria
Published: April 2020

We employed MM+ molecular mechanical modeling and scanning tunneling microscopy (STM) in order to analyze the initial steps of nanoassembly of meso-tetraphenylporphine H2 TPP and its cobalt(II) complex CoTPP on the surface of highly-oriented pyrolytic graphite (HOPG)
and single-walled carbon nanotubes (SWNTs). According to the MM+ results, monolayer H2 TPP adsorption is more favorable energetically than the formation of porphyrin stacks on both graphite and nanotube sidewall; the formation of parallel interacting chains of H2 TPP
on graphite is more preferable than the growth of long single chains; and the assembly into a long-period helixis favored versus the formation of a short-period helixon SWNT sidewall. STM observations of CoTPP complex deposited onto bare HOPG and onto the graphite with deposited SWNTs are
consistent with theoretical results. At the same time, both CoTPP single chains and ribbons were observed on HOPG. The formation of short-period helices on the nanotube sidewalls was concluded to be more likely than the long-period helical nanoassembly.
Characteristics of Dielectrophoretically Aligned UV-Blue GaN Nanowire LEDs
Authors: Kim Tae-Hong , Lee Seung-Yong , Kim Hyung-Gu , Kim Sang-Hoon , Hong Chang-Hee , Hahn Yoon-Bong , Lee Sang-Kwon
Published: April 2020

This is a report on the characteristics of UV-blue light emitting diodes (LEDs) containing homojunction gallium nitride (GaN) nanowires (NWs). These LEDs were prepared by the dielectrophoresis assisted assembly deposition (DAAD) method. The incorporation of an additional silicon dioxide
(SiO2) and a Au capping metal layer was found to improve the electrical and optical properties of the DAAD-prepared GaN NW LEDs. These LEDs exhibited a parasitic series resistance of 120–180 kΩ with a sharp turn-on forward voltage of 3.4–4.0 V and had as low as ∼7
× 10−7 A of leakage current for a reverse bias of −10 V. Typical electroluminescence (EL) spectra, observed from these LEDs under a forward bias, had a broad ultraviolet (UV)-blue emission with a wavelength of 388–422 nm. These LEDs could be seen with the
naked eye. We concluded that the high-brightness EL spectra resulted from the enhancement of the carrier injection due to the size effect of the n-GaN nanowires on the p-GaN substrate.
Influence of Organic Polymers as Capping Agent on Structural and Optical Properties of ZnS:Mn2+ and CdS Nanocrystals
Authors: Keshari Ashish K. , Kumar M. , Singh Prashant K. , Pandey Avinash C.
Published: April 2020

We have synthesized the luminescent ZnS:Mn2+ and bare CdS nanocrystals by employing polyvinyl alcohol (PVA), citric acid (CA) and biotin as organic capping agents by chemical co-precipitation route. The synthesized materials were characterized by X-ray diffraction, small
angle X-ray scattering and transmission electron microscopy for the structural analysis, while UV-Visible spectroscopy and photoluminescence (PL) for optical properties. The results show that all the three organic polymers have the same effect and are capable of controlling the growth of the
nanoclusters. From UV-Visible absorption spectra, it was observed that different capping agents do not affect the band gap of ZnS:Mn2+ system as well, while capping effect clearly observed on PL properties of ZnS:Mn2+ system. We have observed a novel result that capping
with biotin show excellent photo-luminescence as compared to capping of PVA and CA on ZnS:Mn2+-systems. On the other hand, the annealing of these systems leads to degradation of luminescence intensity.
The Red-Shift of Surface Plasmon Absorption of 2D Nanogold Arrangement from Disordered to Ordered
Authors: Tang Junke , Li Jinru , Rong Huiling , Zou Bingsuo , Jiang Long
Published: April 2020

In this article, the changing of surface plasmon resonance (SPR) absorption of 2D arrangement of Au (3 nm) nanoparticles coated with 1-dodecanethiol (C12H25SH), obtained at different desolvation extents, had been investigated. It has been found that an obvious
red-shifted happened when these arrays changed from loose, disordered to close-packed and ordered. Both transmission electron microscopy pictures and variation of SPR absorption of these arrays showed that the formation of long range two-dimension (2D) arrangement of nanoparticles coated with
C12H25SH might be involved in two stages: At the first stage the particles can move freely and random patterns from loose to close package was driven by the Brownian Movement of solvated particles and as a result the voids were eliminated. The red shift of SPR absorption
with the coverage (dλ/d) is relative low. At the second stage, where the particles cannot move freely because of lack of solvent and a long-range two-dimension crystal was formed, the SPR shift to a longer wavelength with a larger dλ/d.
It is mainly attributed to the strong increase of the orientation and dipolar moment of the absorbed C12H25SH molecule on nanoparticles.
Intercalation of Collagen and Soybean Peptides into Zn–Al Layered Double Hydroxide
Authors: Aisawa Sumio , Yasutake Aiko , Takahashi Satoshi , Hirahara Hidetoshi , Narita Eiichi
Published: April 2020

In order to develop a new type biocompatible organic/inorganic nanohybrid material, an intercalation of collagen peptides (CP) and soybean peptide (SP) into Zn–Al layered double hydroxide (LDH) by the coprecipitation reaction has been investigated. The peptide/LDH has been characterized
by chemical analysis, powder X-ray diffraction (XRD), Raman spectroscopy, thermal gravimetric analysis (TG) and transmission electron microscopy (TEM). According to the XRD patterns and Raman spectra, the solid products were found to contain peptide and to show broad diffraction peaks with
LDH structures. The CP/LDH and SP/LDH possess the expanding LDH structure, d00l = 2–3 nm, confirming that both peptides were intercalated into the LDH interlayer space with low organized stacking arrangement.
Spectroscopic Analysis on Metal-Oxide-Semiconductor Light-Emitting Diodes with Buried Si Nanocrystals and Nano-Pyramids in SiOx Film
Authors: Lin Gong-Ru
Published: April 2020

The difference between the white and near-infrared electroluminescence of metal-oxide-semiconductor light-emitting diodes fabricated on 1,100 °C-annealed Si-rich SiOx/p-Si substrate with interfacial pyramidal Si dots (Si nano-pyramids)was characterized.
By changing the substrate temperature and induced coupled plasma power during the plasma enhanced chemical vapor deposition of Si-rich SiOx films, the effects of the growth conditions on the defect- and Si nano-pyramid-related carrier transport and Si nanocrystal-related
electroluminescence spectroscopy were also investigated. The annealed Si-rich SiOx/p-Si films grown at higher synthesized substrate temperate (350 °C)show the larger Si nano-pyramids precipitating near the Si/SiO2 interface. The indium tin oxide/Si-rich
SiOx/p-Si/Al metal-oxide-semiconductor light-emitting diodes with Si-rich SiOx films exhibit different white-light electroluminescence spectra at wavelengths from 400 to 650 nm. The Si nanocrystal-related electroluminescence spectra at 650–850
nm are confirmed, whereas the electroluminescence spectra are shorter wavelengths is attributed to oxygen related defects. These defects become an electron-preferred transporting path within the Si-rich SiOx film, whose densities are decreased by increasing the substrate
temperature or reducing the induced coupled plasma power. Defect-related white-light electroluminescence emits power for a relatively short lifetime. The lifetime can be lengthened and the electroluminescence power can be raised simultaneously by increasing deposition temperature to 350 °C
and adjusting the induced coupled plasma power to a threshold of 30 W, which effectively increases the densities of Si nanocrystals and nano-pyramids in the Si-rich SiOx film with Si concentration of up to 40 at%. A nearly defect-free Si-rich SiOx sample
can be grown under such conditions, which contributes to the most stable and largest near-infrared electroluminescence with the longest lifetime, although the power–current slope of purely Si nanopyramid related electroluminescence at near-infrared wavelengths is slightly lower.
Growth and Optical Properties of ZnO Low-Dimensional Nanostructures
Authors: Liu Yichun , Tong Yanhong
Published: April 2020

Recent studies on the growth of ZnO nanostructures and their optical properties were reviewed. Using different methods, a variety of ZnO nanostructures, including quantum dots nanotowers, nanotubes, nanorods, nanowires, and nanosheets, displaying zero, one, and two dimensions, have
been synthesized. The growth of ZnO low-dimensional nanostructures has been demonstrated. Their optical properties have been studied by means of room-temperature photoluminescence spectra, low-temperature photoluminescence spectra, temperature-dependent photoluminescence spectra, and pressure-dependent
photoluminescence spectra. The optical properties can be adjusted by the surface features of ZnO low-dimensional nanostructures. The strong exciton emission has been observed in some nanostructures, showing promising potential in nanodevice applications.
Recent Progress on the Spectroscopy of Rare Earth Ions in Core–Shells, Nanowires, Nanotubes, and Other Novel Nanostructures
Authors: Chen Xueyuan , Liu Liqin , Liu Guokui
Published: April 2020

Research and development of nanoscale luminescent and laser materials are part of the rapidly advancing nanoscience and nanotechnology. Because of unique spectroscopic properties and luminescent dynamics of f-electron states, doping luminescent rare earth ions into nano-hosts
has been demonstrated as an optimistic approach to developing highly efficient and stable nanophosphors for various applications. In this article, we review the most recent progress in spectroscopic measurements of rare earth ion-activated low-dimensional nanostructures including nanolayers,
core–shells, nanowires, nanotubes, and nanodisks. Among a large volume of work reported in the literature on many members of the rare earth series including Ce3+, Pr3+, Nd3+, Eu3+, and Er3+, we focus on recent findings in the spectroscopic
and luminescence properties of Eu3+ doped nanolayers, core–shells, and nanotubes, because Eu3+ ions have been extensively studied and widely used as an ideal probe for fundamental understanding of nano-phenomena. Specifically, the dependence of the optical properties
of rare earth ions on nanostructures is discussed in detail.
Nanostructured CaWO4, CaWO4:Eu3+ and CaWO4:Tb3+ Particles: Sonochemical Synthesis and Luminescent Properties
Authors: Li Chunxia , Lin Cuikun , Liu Xiaoming , Lin Jun
Published: April 2020

Nanostructured CaWO4, CaWO4:Eu3+, and CaWO4:Tb3+ phosphor particles were synthesized via a facile sonochemical route. X-ray diffraction, Fourier transform infrared spectroscopy, field emission scanning electron microscopy, transmission
electron microscopy, photoluminescence, low voltage cathodoluminescence spectra, and photoluminescence lifetimes were used to characterize the as-obtained samples. The X-ray diffraction results indicate that the samples are well crystallized with the scheelite structure of CaWO4.
The transmission electron microscopy and field emission scanning electron microscopy images illustrate that the powders consist of spherical particles with sizes from 120 to 160 nm, which are the aggregates of even smaller nanoparticles ranging from 10 to 20 nm. Under UV light or electron
beam excitation, the CaWO4 powder exhibited a blue emission band with a maximum at 430 nm originating from the WO2−4 groups, while the CaWO4:Eu3+ powder showed red emission dominated by 613 nm ascribed to the 5D0
→ 7F2 of Eu3+, and the CaWO4:Tb3+ powders showed emission at 544 nm, ascribed to the 5D4 → 7F5 transition of Tb3+. The PL excitation and emission spectra suggest that the
energy is transferred from WO2−4 to Eu3+CaWO4:Eu3+ and to Tb3+ in CaWO4:Tb3+. Moreover, the energy transfer from WO2−4 to Tb3+ in CaWO4:Tb3+
is more efficient than that from WO2−4 to Eu3+ in CaWO4:Eu3+. This novel and efficient pathway could open new opportunities for further investigating the novel properties of tungstate materials.
Optical Dephasing of Triply Ionized Rare Earths in Transparent Glass Ceramics Containing LaF3 Nanocrystals
Authors: Zheng Hairong , Zhang Xiangyu , Gao Dangli , Meltzer Richard S.
Published: April 2020

Optical dephasing of Pr3+ and Tm3+ ions doped in transparent oxyfluoride glass ceramics was studied with the two-pulse photon echo technique. It was found that the dephasing time of rare earth ions is dramatically less in nanocrystals embedded in a glass matrix
than in bulk crystals. Aquasi-linear temperature dependence obtained at low temperatures proved that the long-range interaction of the ions inside the nanocrystals with the two level systems of the glass matrix dominates the optical dephasing. The local thermal effect in glass ceramics containing
nanocrystals elevates the local temperature, which results in the reduction of optical dephasing time. For Tm3+-doped glass ceramics, the elevation of local temperature induced by the irradiation of excitation laser even quenched the photon echo signals in the experimental study.
Hydrothermal Synthesis and Luminescent Properties of Microtubes Constructed by Fluffy Zns:Mn2+ with Nanostructures
Authors: Chen Li , Zhang Jiahua , Zhao Haifeng , Wang Xiaojun
Published: April 2020

Tubular micrometer-sized ZnS:Mn2+ constructed by fluffy nanostructures were fabricated in the mixed solutions of water and ethanol in a fixed volume ratio with the aid of ethylenediamine. In the X-ray diffraction pattern, the products obtained in the presence and absence
of ethylenediamine show the wurtzite and sphalerite phases, respectively. Field-emission scanning electron microscopic images reveal the evolution process from nanowires to fluffy ZnS:Mn2+ to microtubes with the reaction times of 2, 4, and 8 hours at 100 °C, and the basal nanowires
are below 10 nm in diameter. Photoluminescence and photoluminescence excitation spectra were investigated. The results suggest that the wurtzite phase, instead of the sphalerite phase ZnS:Mn2+ is luminescence-active for the 4T1–6A1
transition of the Mn2+ in the ZnS host. The excitation spectra monitored at orange emission bands exhibit sharp peaks at 320, 326 and 327 nm with increasing reaction times of 2, 4, and 8 hours, respectively, indicating the energy transfer from ZnS host to Mn2+ ions, and
the blue-shifts compared with the band gap absorption of the bulk counterpart (344 nm) are also observed due to the quantum confinement effects. The formation mechanism of the wurtzite one-dimensional nanostructures at such a low temperature is proposed based on a molecular template mechanism
involving the bidentate coordinating ligand, ethylenediamine, and the possible formation mechanism of novel tubular structure are also discussed.
Influencing Factors on Erbium-Doped Polymer Waveguide Amplifier
Authors: Zhang Dan , Wang Yu , Wu AiHua , Zhang XiZhen , Chen Cong , Sun Xu , Li Bin , Zhang Daming
Published: April 2020

We used fundamental rate equations and power propagation equations to simulate the gain factors of Er3+-doped polymer excited at 980 nm. The results of the calculations indicate close relationships between the gain and Er3+ concentration, pump and signal absorption
cross-sections, waveguide dimension, and metastable state lifetime of the states 4I13/2. When the signal absorption cross section doubles, the gain will increase threefold. The radiative lifetime of Er3+ in inorganic materials is much longer (milliseconds)
than in the polymer (microseconds). If the lifetime of the states 4I13/2 decreases one level, there must be a corresponding increase in pump power so that the gain remains at the same level.
Self-Assembly of Yb3+-Tm3+ Co-Doped YF3 Elongated Nanocrystals into Nanobundles of Straw and Up-Conversion Fluorescence
Authors: Zhang Jishuang , Qin Weiping , Zhang Jisen , Wang Yan , Cao Chunyan , Jin Ye , Wei Guodong , Wang Guofeng , Wang Lili
Published: April 2020

The hierarchical self-assembly of Yb3+ and Tm3+ co-doped YF3 elongated nanocrystals (NCs) into nanobundles of straw were synthesized through a facile hydrothermal route. The formational mechanisms of regular aggregates of the building blocks were studied.
Ultraviolet (UV)-blue upconversion emissions of Tm3+ were recorded under 980-nm excitation by the Yb3+ sensitizer. The relatively bright blue emission indicated that the bundles have the potential for applications such as short-wavelength solid-state lasers and display
devices.
Preparation, Characterization and Spectroscopy of Eu3+ in Gd2O3 Nanorods
Authors: Liu Liqin , Ma En , Li Renfu , Chen Xueyuan
Published: April 2020

Eu3+:Gd2O3 nanorods were prepared by a hydrothermal method. X-ray diffraction, field-emission scanning electron microscopy, transmission electron microscopy, and Fourier transform-infrared spectroscopy were used to characterize the resulting samples.
Emission and excitation spectra were studied using xenon excited spectroscopic experiments at 10 K. Energy transfer from Gd3+ to Eu3+, from the band gap of the host to Eu3+, and from Eu3+ (S6) to Eu3+ (C2) was observed.
The energy levels of Eu3+ at the C2 site of cubic Gd2O3 were experimentally determined according to the fluorescence spectra at 10 K, and fit well with the theoretical values. The standard deviation for the optimal fit was 12.9 cm−1.
The fluorescent lifetime of 5D0 (2.3 ms at 295 K) was unusually longer than that of the bulk counterparts (0.94 ms), indicating a small filling factor (0.55) for the nanorod volume. However the lifetime of 5D1 was much shorter than that of the bulk
counterparts, 65 μs at 10 K, 37 μs at 295 K.
Luminescent Properties of La3PO7:Eu3+ Nanoparticles
Authors: Lü Shaozhe , Zhang Jishen
Published: April 2020

La3PO7:Eu3+ samples were prepared by combustion and annealing and characterized by X-ray diffraction and transmission electron microscopy. It was found that the average size of the particles is about 80 nm. The red emission from the 5D0
→ 7F2 transition of the Eu3+ ions under ultraviolet light excitation is much stronger than the orange emission from the 5D0 → 7F1 transition. The emission spectra, charge transfer band, laser selective excitation
spectra, and time-resolved spectra indicate that symmetry of the local environment of Eu3+ lacks an inversion center and Eu3+ ions occupy at least two types of sites in the La3PO7 crystal. The superior color chromaticity compared to other phosphates
and borates doped with Eu3+ means La3PO7:Eu3+ may have potential as a luminescent material.
Self-Assembly of α-MnO2 Nanorods into Spheres: Synthesis and Electrochemical Properties
Authors: Song Xu Chun , Zheng Yi Fan , Yang E. , Wang Yun
Published: April 2020

The α-MnO2 spherical assemblies were prepared via a facile hydrothermal approach in the presence of sodium dodecyl sulfate (SDS). The assembled nanostructures were composed of the MnO2 nanorods with 150–200 nm in width and several micrometers
in length. The products were characterized by SEM, TEM and XRD. The electrochemical characterization was carried out by cyclic voltammetry, which indicated that the α-MnO2 spherical assemblies were of an excellent electrode material for supercapacitor.
A Highly Ordered Self-Assembly Three-Grade Porous Helical Silica Tube
Authors: Gao Fei , Dong Lin , Kong Yan , Zhang Yanhua , Wu Xingcai , Tao Yourong , Zhu Haiyang , Lü Yinong , Chen Yi
Published: April 2020

A novel three-grade porous helical silica tube is prepared through an ingenious multi-soft-template pathway. This study reveals that three-(or multi-)grade self-assembly porous structure can be realized by using the synergistic effect of soft-templates. Our finding can offer an opportunity
for nanofabrication including rational molecular design, spatial control on a nanoscale, and hierarchical assembly of complexarchitectures of porous materials.
Structure-Property Relationship in Polyethylene Reinforced by Polyethylene-Grafted Multi-Walled Carbon Nanotubes
Authors: Causin Valerio , Yang Bing-Xing , Marega Carla , Goh Suat Hong , Marigo Antonio
Published: April 2020

Polyethylene-grafted multiwalled carbon nanotubes (PE-g-MWNT) were used to reinforce polyethylene (PE). The nanocomposites possessed not only improved stiffness and strength, but also increased ductility and toughness. The effects on the structure and morphology of composites due to
pristine multiwalled carbon nanotubes (MWNT) and PE-g-MWNT were studied and compared using small angle X-ray scattering (SAXS), wide angle X-ray diffraction (WAXD) and differential scanning calorimetry (DSC). The SAXS long period, crystalline layer thickness and crystallinity of polymer lamellar
stacks were found to decrease significantly in MWNT composites, while the decreases were much smaller in PE-g-MWNT composites. PE-g-MWNT allowed a more efficient and unhindered crystallization at a lamellar level, while MWNT disrupted the order of lamellar stacks, probably because of their
tendency to aggregate. The SAXS crystallinity and the mechanical properties of the composites showed similar trends as a function of MWNT content. This suggested that the improvement of the interfacial strength between polymer and carbon nanotubes was a result of synergistic effects of better
dispersion of the filler, better stress transfer, due to the grafting of polymer and MWNT, and the nucleation of a crystalline phase around MWNT. The latter effect was confirmed by measurements of kinetics of non-isothermal crystallization.