bluuebunny/crossref_metadata_2025 huggingface dataset:
Frequent Antiviral Treatment Failures in Patients Infected With Hepatitis C Virus Genotype 4, Subtype 4r
Authors: Fourati Slim , Rodriguez Christophe , Hézode Christophe , Soulier Alexandre , Ruiz Isaac , Poiteau Lila , Chevaliez Stéphane , Pawlotsky Jean‐Michel
Published: August 2018

Hepatitis C virus (HCV) genotype 4 is highly heterogeneous. HCV subtype 4r has been suggested to be less responsive to direct‐acting antiviral (DAA) drug treatment than other genotype 4 subtypes. Among 537 DAA‐treated patients who experienced a virological failure (VF) in France between 2015 and 2018, 121 (22.5%) were infected with genotype 4 and 27 of them (22.3%) with subtype 4r; subtype 4r was thus over‐represented as compared to its prevalence in the French general population. Population sequencing of the nonstructural protein (NS) 3, NS5A, and NS5B genes was performed in all subtype 4r patients at treatment failure and in 6 at baseline, whereas full‐length HCV genome sequencing was performed in two baseline and three treatment failure samples by means of an original shotgun metagenomics method based on deep sequencing. At treatment failure, all subtype 4r patients harbored two to three dominant NS5A resistance‐associated substitutions (RASs), including at least L28A/C/I/M/V and L30R. Among 13 patients exposed to sofosbuvir and an NS5A inhibitor (daclatasvir, ledipasvir, or velpatasvir), 5 (38.5%) also harbored NS5B S282C/T RASs at treatment failure. An additional patient harbored S282C/T RASs at treatment failure by deep sequencing. Prevalence of S282C/T RASs at treatment failure was significantly higher in patients infected with genotype 4r than with other genotypes, including other subtypes of genotype 4. Conclusion: The lower rates of sustained virological response in patients infected with subtype 4r are related to the frequent preexistence at treatment baseline and subsequent selection by DAA treatment of both NS5A and NS5B S282 RASs. Our study suggests that these patients should be identified and receive a triple DAA combination regimen as first‐line treatment.
The effects of topography and forest management on water storage in catchments in south‐central Chile
Authors: Barrientos Guillermo , Iroumé Andrés
Published: August 2018

Our work analyses the intra‐annual variability of the volume of water stored in 15 forested headwater catchments from south‐central Chile, aiming at understanding how forest management, hydrology, and climate influence the dynamic components of catchment storage. Thus, we address the following questions: (a) How does the annual water storage vary in catchments located in diverse hydroclimatic conditions and subject to variable forest management? (b) Which natural (i.e., hydrologic regime and physiographic setting) and anthropogenic factors explain the variance in water storage? Results show that the annual catchment storage increases at the beginning of each hydrological year in direct response to increases in rainfall. The maximum water storage ranges from 666 to 1,272 mm in these catchments. The catchments with Pinus or Eucalyptus spp. cover store less water than the catchments with mixed forest species cover. Forest cover (biomass volume, plantation density, and percentage of plantation and age) has the primary control on dynamic storage in all catchments. These results indicate that forest management may alter the catchment water storage.
Annexin A2 (ANX A2): An emerging biomarker and potential therapeutic target for aggressive cancers
Authors: Sharma Mahesh C.
Published: August 2018

ANX A2 is an important member of annexin family of proteins expressed on surface of endothelial cells (ECs), macrophages, mononuclear cells and various types of cancer cells. It exhibits high affinity binding for calcium (Ca++) and phospholipids. ANX A2 plays an important role in many biological processes such as endocytosis, exocytosis, autophagy, cell–cell communications and biochemical activation of plasminogen. On the cell surface ANX A2 organizes the assembly of plasminogen (PLG) and tissue plasminogen activator (tPA) for efficient conversion of PLG to plasmin, a serine protease. Proteolytic activity of plasmin is required for activation of inactive pro‐metalloproteases (pro‐MMPs) and latent growth factors for their biological actions. These activation steps are critical for degradation of extracellular matrix (ECM) and basement proteins (BM) for cancer cell invasion and metastasis. Increased expression of ANX A2 protein/gene has been correlated with invasion and metastasis in a variety of human cancers. Moreover, clinical studies have positively correlated ANX A2 protein expression with aggressive cancers and with resistance to anticancer drugs, shorter disease‐free survival (DFS), and worse overall survival (OS). The mechanism(s) by which ANX A2 regulates cancer invasion and metastasis are beginning to emerge. Investigators used various technologies to target ANX A2 in preclinical model of human cancers and demonstrated exciting results. In this review article, we analyzed existing literature concurrent with our own findings and provided a critical overview of ANX A2‐dependent mechanism(s) of cancer invasion and metastasis.
Synthesis and Applications of Endohedrally Functionalized Metal‐Ligand Cage Complexes
Authors: Bogie Paul M. , Miller Tabitha F. , Hooley Richard J.
Published: August 2018

Self‐assembled cages have garnered wide‐spread interest as supramolecular hosts. Their abilities may be augmented through the installation of functional groups on the interior of the cage. This article highlights recent advances in the applications of endohedral functionalization in control of overall self‐assembly, molecular recognition and reactivity, with an emphasis on installing functionalization that enables biomimetic catalysis.
Saturated two‐photon excitation fluorescence microscopy for the visualization of cerebral neural networks at millimeters deep depth
Authors: Chakraborty Sandeep , Lee Szu‐Yu , Lee Jye‐Chang , Yen Chen‐Tung , Sun Chi‐Kuang
Published: August 2018

Optical imaging is a key modality for observing biological specimen with higher spatial resolution. However, scattering and absorption of light in tissues are inherent barriers in maximizing imaging depth in biological tissues. To achieve this goal, use of light at near‐infrared spectrum can improve the present situation. Here, the capability of saturated two‐photon saturated excitation (TP‐SAX) fluorescence microscopy to image at depths of >2.0 mm, with submicron resolution in transparent mouse brain imaging, is demonstrated. At such depths with scattering‐enlarged point spread function (PSF), we find that TP‐SAX is capable to provide spatial resolution improvement compared to its corresponding TPFM, which is on the other hand already providing a much improved resolution compared with single‐photon confocal fluorescence microscopy. With the capability to further improve spatial resolution at such deep depth with scattering‐enlarged PSF, TP‐SAX can be used for exquisite visualization of delicate cerebral neural structure in the scattering regime with a submicron spatial resolution inside intact mouse brain.
Identification of synthetic lethality based on a functional network by using machine learning algorithms
Authors: Li JiaRui , Lu Lin , Zhang Yu‐Hang , Liu Min , Chen Lei , Huang Tao , Cai Yu‐Dong
Published: August 2018

Synthetic lethality is the synthesis of mutations leading to cell death. Tumor‐specific synthetic lethality has been targeted in research to improve cancer therapy. With the advances of techniques in molecular biology, such as RNAi and CRISPR/Cas9 gene editing, efforts have been made to systematically identify synthetic lethal interactions, especially for frequently mutated genes in cancers. However, elucidating the mechanism of synthetic lethality remains a challenge because of the complexity of its influencing conditions. In this study, we proposed a new computational method to identify critical functional features that can accurately predict synthetic lethal interactions. This method incorporates several machine learning algorithms and encodes protein‐coding genes by an enrichment system derived from gene ontology terms and Kyoto Encyclopedia of Genes and Genomes pathways to represent their functional features. We built a random forest‐based prediction engine by using 2120 selected features and obtained a Matthews correlation coefficient of 0.532. We examined the top 15 features and found that most of them have potential roles in synthetic lethality according to previous studies. These results demonstrate the ability of our proposed method to predict synthetic lethal interactions and provide a basis for further characterization of these particular genetic combinations.
Ulinastatin attenuates liver injury and inflammation in a cecal ligation and puncture induced sepsis mouse model
Authors: Song Yukang , Miao Shixing , Li Yexuzi , Fu Hui
Published: August 2018

Sepsis is a syndrome of life‐threatening multiorgan dysfunction caused by host response dysregulation to infection. Ulinastatin (UTI), a serine protease inhibitor, possesses anti‐inflammatory properties and has been suggested to modulate lipopolysaccharide‐induced sepsis. However, little is known about the mechanism underlying its effects on sepsis. In the current study, we investigated the protective effect of UTI on liver injury in a cecal ligation and puncture (CLP)‐induced sepsis of C57BL/6 mouse model and explored the possible mechanisms. Mice underwent CLP as sepsis models and were randomized into five groups including the sham group, UTI group, CLP group, UTI‐L group, and UTI‐H group. UTI was intraperitoneally administered at doses of UTI 1500 U/100 g (UTI‐L group) or 3000 U/100 g (UTI‐H group), before CLP. The mice were killed, and immunohistochemical changes, cytokine levels, and antioxidant enzyme activities were detected. Our results showed that UTI ameliorated CLP‐mediated increases in serum aspartate aminotransferase and alanine aminotransferase activities, histological activity index, degenerative region ratio, and infiltrated inflammatory cell numbers. Moreover, UTI also decreased nitrotyrosine and 4‐hydroxynonenal, activated caspase‐3, and activated poly (ADP‐ribose) polymerase (PARP) levels and inhibited the mitogen‐activated protein kinase pathway activation in liver tissues. Our results indicated that UTI could inhibit CLP‐induced liver injury by suppressing inflammation and oxidation. Our results indicated that UTI may serve as a potential therapeutic agent for sepsis.
Transcriptome mining of non‐BRCA1/A2 and BRCA1/A2 familial breast cancer
Authors: Akbari Vahid , Kallhor Marzieh , Akbari Mohammad Taghi
Published: August 2018

About 10% of all breast cancer cases are the familial type. Mutations in two highly penetrance breast cancer susceptibility genes, BRCA1 and BRCA2, can only explain 20% to 25% of genetic susceptibility to breast cancer, and most familial breast cancer cases have intact BRCA1 and BRCA2 genes that refer to non‐BRCA1/A2 or BRCAX familial breast cancer. Despite extensive studies, more than 50% of genetic susceptibility to breast cancer remained to be disclosed. Finding the differences between these two types of breast cancer (non‐BRCA1/A2 and BRCA1/A2) at genomic, transcriptomic, and proteomic levels can help us to elucidate fundamental molecular processes and develope more promising therapeutic targets. Here, we used expression data of 391 patients with familial breast cancer including 195 non‐BRCA1/A2 and 196 BRCA1 and/or BRCA2 cases from four independent studies by means of meta‐analysis to find differences in gene expression signature between these two types of familial breast cancer. As well as, we applied comprehensive network analysis to find crucial protein complexes and regulators for each condition. Our results revealed significant overexpression of cell cycle processes in BRCA1/A2 patients and significant overexpression of estrogen axis in non‐BRCA1/A2 patients. Moreover, we found FOXM1 as the central regulator of cell cycle processes and GATA3, FOXA1, and ESR1 as the main regulators of estrogen axis.
Molecular characterization of lung adenocarcinoma: A potential four–long noncoding RNA prognostic signature
Authors: Sui Jing , Yang Sheng , Liu Tong , Wu Wenjuan , Xu Siyi , Yin Lihong , Pu Yuepu , Zhang Xiaomei , Zhang Yan , Shen Bo , Liang Geyu
Published: August 2018

Background

Lung adenocarcinoma (LUAD), mainly originated in lung glandular cells, is the most frequent pathological type of lung cancer and the 5‐year survival rate of LUAD patients is still very low. Therefore, we aim to identify a long noncoding RNA (lncRNA)–related signature as the sensitive and novel prognostic biomarkers.

Methods

The associations between survival outcome and the intersection of lncRNAs were obtained from The Cancer Genome Atlas (TCGA) database. By the univariate and multivariate Cox analyses, key lncRNAs were identified to construct the prognostic model. The model was estimated by survival analysis and receiver operating characteristic curve, and verified by the Kaplan‐Meier (K‐M) plotter and quantitative reverse‐transcription polymerase chain reaction (qRT‐PCR). Functional enrichment analysis was also performed.

Results

A four‐lncRNA signature (CEBPA‐AS1, GVINP1, MIR31HG, and RAET1K) was developed after Cox analysis. The power of the four‐lncRNA prognostic signature was effective in the TCGA database. The results from by the K‐M plotter and qRT‐PCR validation were consistent with our TCGA bioinformatics results. Furthermore, Gene Ontology and pathway analysis revealed the tumorigenic and prognostic function of the four lncRNAs.

Conclusions

By mining the TCGA data, we built a four‐lncRNA signature, which could effectively predict prognosis of LUAD. In the future, an independent cohort is needed to validate our findings.

Impact

The four‐lncRNA signature could become potential prognostic indicator of LUAD in the future.
Retracted: Deletion of long noncoding RNA EFNA3 aggravates hypoxia‐induced injury in PC‐12 cells by upregulation of miR‐101a
Authors: Gong Weijun , Qie Shuyan , Huang Peiling , Xi Jianing
Published: August 2018

Long noncoding RNAs (lncRNAs) have been reported to be involved in several neurological pathogenesis conditions including cerebral ischemia. In the current study, the functions of lncRNA EFNA3 on hypoxia‐injured rat adrenal pheochromocytoma (PC‐12) cells and the underlying molecular mechanism were studied. The expression of lncRNA EFNA3 was silenced by short hairpin RNA transfection, after which the cells were subjected with hypoxia. Cell viability, migration, invasion, and apoptosis were, respectively, determined by trypan blue staining, Transwell assay, annexin V‐fluorescein isothiocyanate (FITC)/propidium iodide (PI) double‐staining, and Western blot analysis. The cross regulation between lncRNA EFNA3 and miR‐101a, as well as between miR‐101a and Rho associated coiled‐coil containing protein kinase 2 (ROCK2) were detected by performing quantitative real‐time polymerase chain reaction, RNA pull‐down, RNA immunoprecipitation, luciferase activity assay, and Western blot analysis. Studies showed that lncRNA EFNA3 was highly expressed in response to hypoxia. Deletion of lncRNA EFNA3 significantly aggravated hypoxia‐induced injury in PC‐12 cells, as the impairment of cell viability, migration, and invasion, and the inducement of apoptosis. LncRNA EFNA3 worked as a sponging molecule for miR‐101a and miR‐101a suppression‐protected PC‐12 cells against hypoxia‐induced injury even when lncRNA EFNA3 was silenced. ROCK2 was a target gene of miR‐101a. ROCK2 overexpression exhibited neuroprotective activities. Besides, ROCK2 overexpression activated Wnt/β‐catenin pathway whereas it deactivated JAK/STAT pathway upon hypoxia. Our study suggests that deletion of lncRNA EFNA3 aggravates hypoxia‐induced injury in PC‐12 cells by upregulating miR‐101a, which further targets ROCK2.
Perovskite solar cells using TiO2 layers coated with metal‐organic framework material ZIF‐8
Authors: Chung Ho‐Yang , Lin Chia‐Her , Prabu Samikannu , Wang Hong‐Wen
Published: August 2018

A metal‐organic framework of ZIF‐8 is used as an interlayer between the mesoporous TiO2 and the perovskite layer in perovskite solar cells (PSCs). The ZIF‐8 solution is dried on the mesoporous TiO2 layer, which can then act as an additional light absorbing layer at the short‐wavelength range for the solar cells, leading to improved performance of the cell. After an immersion time of 1–5 min, a very thin ZIF‐8 film is formed on TiO2. An enhancement in the incident photon to current conversion efficiency (IPCE) is achieved for PSCs using the ZIF‐8‐coated TiO2 layer. The conversion efficiency of PSCs is improved from 9.6 to 12.0% when ZIF‐8 is present. UV–vis and photoluminescence (PL) spectra are used to investigate the beneficial effect of ZIF‐8/TiO2 hybrid layers.
Ultrasonography and autopsy correlation of fetal hypoplastic left heart syndrome
Authors: Kumar Manisha , Priyam
Published: August 2018

Hypoplastic left heart syndrome (HLHS) represents a spectrum of abnormalities which marks the underdevelopment of left side cardiac structures. We present the ultrasound and autopsy correlation of two cases with HLHS with core pathology as isolated mitral atresia in one and aortic atresia in another. In both the cases after diagnostic confirmation on ultrasound (US), the couple opted for termination of pregnancy and consented for autopsy. The correlation of US and autopsy images of HLHS, facilitated our understanding of pathology behind the image obtained on US. The autopsy not only confirmed the antenatal diagnosis, but also added new findings.
Autoimmunity and immune system dysregulation in schizophrenia: IgGs from sera of patients hydrolyze myelin basic protein
Authors: Parshukova Daria , Smirnova Liudmila P. , Ermakov Evgeny A. , Bokhan Nikolay A. , Semke Arkadiy V. , Ivanova Svetlana A. , Buneva Valentina N. , Nevinsky Georgy A.
Published: August 2018

Several different theories of schizophrenia (SCZ) were discussed; the causes of this disease are not yet clear. Using ELISA, it was shown that titers of autoantibodies against myelin basic protein (MBP) in SCZ patients are ~1.8‐fold higher than in healthy individuals but 5.0‐fold lower than in patients with multiple sclerosis. Several rigid criteria were checked to show that the MBP‐hydrolyzing activity is an intrinsic property of SCZ IgGs. Approximately 82% electrophoretically homogeneous SCZ IgGs purified using several affinity sorbents including Sepharose with immobilized MBP hydrolyze specifically only MBP but not many other tested proteins. The average relative activity of IgGs from patients with negative symptoms was 2.5‐fold higher than that of patients with positive symptoms of SCZ, and it increases with the duration of this pathology. It was shown that abzymes are the earliest statistically significant markers of many autoimmune pathologies. Our findings surmise that the immune systems of individual SCZ patients can generate a variety of anti‐MBP abzymes with different catalytic properties, which can attack MBP of the myelin‐proteolipid shell of axons. Therefore, autoimmune processes together with other mechanisms can play an important role in SCZ pathogenesis. MBP‐hydrolyzing antibodies were previously detected in the blood of 80% to 90% of patients with systemic lupus erythematosus (SLE) and multiple sclerosis (MS). In addition, some similar neuropsychiatric indicators of disease common to SLE, MS, and SCZ were described in the literature. Thus, the destruction of the myelin sheath and the production of MBP‐hydrolyzing antibodies can be a common phenomenon for some different diseases.
Limitation of the bandpass filter in preventing oversensing of pectoral myopotentials over the long‐term follow‐up
Authors: Hori Yuichi , Nakahara Shiro , Nishiyama Naoki , Fukuda Reiko , Toratani Noritaka , Sakai Yoshihiko , Taguchi Isao
Published: August 2018

A 60‐year‐old male experienced an inappropriate shock from an implantable cardioverter‐defibrillator (ICD) because of oversensing of pectoral myopotentials. Battery depletion was also observed, and a generator change was performed. A single‐chamber ICD (VENTAK PRIZM II 1860) was changed to a new ICD (INCEPTA VR F161). The myopotentials were clearly eliminated by the difference in the band pass filter (PRIZM; 21‐171 Hz, INCEPTA; 20‐85 Hz), but unfortunately, new noise was documented 4 years later. The utility of the bandpass filter for preventing oversensing of myopotentials was observed, but the limitation of its use for long‐term follow‐up was also indicated.
Seedball‐induced changes of root growth and physico‐chemical properties—a case study with pearl millet
Authors: Nwankwo Charles I. , Blaser Sebastian R. G. A. , Vetterlein Doris , Neumann Günter , Herrmann Ludger
Published: August 2018

Seedball is a cheap “seed‐pelleting‐technique” that combines local materials, seeds and optionally additives such as mineral fertilizer to enhance pearl millet (Pennisetum glaucum (L.) R. Brown) early growth under poor soil conditions. The major objective here was to study the mechanisms behind positive seedball effects. Chemical effects in the rhizosphere and early root development of seedball‐derived pearl millet seedlings were monitored using micro‐suction‐cups to extract soil solutions and X‐ray tomography to visualize early root growth. Pearl millet (single seedling) was grown in soil columns in a sandy soil substrate. Root and shoot biomass were sampled. X‐ray tomography imaging revealed intense development of fine roots within the nutrient‐amended seedball. Seedball and seedball+NPK treatments, respectively, were 65% and 165% higher in shoot fresh weight, and 108% and 227% higher in shoot dry matter than the control treatment. Seedball+NPK seedlings showed promoted root growth in the upper compartment and 105% and 30% increments in root fresh and dry weights. Soil solution concentrations indicate that fine root growth ass stimulated by release of nutrients from the seedballs to their direct proximity. Under real field conditions, the higher root length density and finer roots could improve seedlings survival under early drought conditions due to better ability to extract water and nutrients from a greater soil volume.
Prospective implementation of a standardized screening protocol for deep venous thrombosis in abdominal surgical oncology patients
Authors: Sinnamon Andrew J. , Tong Jason K. C. , Bailey Elizabeth A. , Brown Caitlin , Colbert Latesha , Murray Shannon , Jackson Benjamin M. , Roses Robert E.
Published: August 2018

Background and Objectives

Venous thromboembolism (VTE) remains a major cause of perioperative morbidity and mortality despite implementation of prophylaxis guidelines. We sought to identify risk factors for occult deep venous thrombosis (DVT) following abdominal surgery for cancer and measure the clinical impact of a prospectively implemented standardized postoperative DVT screening protocol.

Methods

Patients undergoing abdominal surgery for malignant indication were screened with early postoperative lower extremity duplex to identify DVT. Clinical and pathologic factors associated with DVT were identified.

Results

Among 255 patients meeting study criteria, 25 (9.8%) had occult lower extremity DVT on routine postoperative screening. Prior history of VTE and lower preoperative hemoglobin were independently associated with DVT (OR, 9.05; P = 0.004; and OR, 1.27; P = 0.025, respectively). Preoperative chemotherapy within 1 year and thrombocytopenia were associated with DVT in univariate analyses only. Five patients developed postoperative pulmonary emboli (2.0%); three following negative duplex and two following positive duplex for distal DVT for which the patients were not therapeutically anticoagulated due to a contraindication. There were no pulmonary emboli in duplex‐positive patients who were anticoagulated or who had vena cava filter placed.

Conclusion

Despite prophylaxis, the prevalence of occult DVT in abdominal oncologic surgery patients is considerable. Postoperative screening duplex can identify these events to guide management.
Robotic (super) microsurgery: Feasibility of a new master‐slave platform in an in vivo animal model and future directions
Authors: van Mulken Tom J. M. , Schols Rutger M. , Qiu Shan S. , Brouwers Kaj , Hoekstra Lisette T. , Booi Darren I. , Cau Raimondo , Schoenmakers Ferry , Scharmga Andrea M. J. , van der Hulst Rene R. W. J.
Published: August 2018

Advanced microsurgical procedures are currently limited by human precision and manual dexterity. The potential of robotics in microsurgery is highlighted, including a general overview of applications of robotic assistance in microsurgery and its introduction in different surgical specialties. A new robotic platform especially designed for (super) microsurgery is presented. Results of an in vivo animal study underline its feasibility and encourage further development toward clinical studies. Future directions of robotic microsurgery are proposed.
Modeling golden eagle‐vehicle collisions to design mitigation strategies
Authors: Lonsdorf Eric , Sanders‐Reed Carol A. , Boal Clint , Allison Taber D.
Published: August 2018

The incidental take of golden eagles (Aquila chrysaetos) as a result of wind energy development requires some form of compensatory mitigation. Although several options have been proposed, only one has been formerly accepted and implemented, and the lack of options can limit the permit process for wind facilities. We developed a model to estimate numbers of golden eagles that die when struck by vehicles when eagles scavenge road kill to evaluate removal of road‐killed carcasses as an additional mitigation option. Our model estimates vehicle collision rates as a function of eagle densities, road traffic volume, and animal carcass abundance at the scale of a Wyoming, USA, county during fall‐winter, and quantifies the effects of different mitigation strategies, including estimates of uncertainty. We evaluated the plausibility of our model estimates by predicting mortality rates for each county in Wyoming and comparing overall state mortality to current estimates of mortality using derived estimates from expert judgment. We also developed a context‐dependent analysis of potential mitigation credits controlling for carcass number, traffic volume, and background carcass removals. We found that mitigation credit should be highest in areas with greatest number of carcasses. Collision mitigation is a potentially useful addition to the mitigation toolbox for wind energy development or other activities that need to offset predicted golden eagle mortality and satisfy incidental take permit requirements. © 2018 The Authors. Journal of Wildlife Management Published by Wiley Periodicals, Inc.
Assessing the severe eutrophication status and spatial trend in the coastal waters of Zhejiang province (China)
Authors: Jiang Q. , He J. , Wu J. , Hu X. , Ye G. , Christakos G.
Published: August 2018

The eutrophication of the coastal waters of Zhejiang Province has become one of the main contamination threats to the region's coastal marine ecosystems. Accordingly, the comprehensive characterization of the eutrophication status in terms of improved quantitative methods is valuable for local risk assessment and policy making. A novelty of this work is that the spatial distributions of chemical oxygen demand, dissolved inorganic nitrogen, and dissolved inorganic phosphorus were estimated across space by the Bayesian maximum entropy (BME) method. The BME estimates were found to have the best cross‐validation performance compared to ordinary kriging and inverse distance weighted techniques. Based on the BME maps, it was found that about 25.95%, 19.18%, 20.53%, and 34.34% of these coastal waters were oligotrophic, mesotrophic, eutrophic, and hypereutrophic. Another novelty of the present work is that comprehensive stochastic site indicators (SSI) were introduced in the quantitative characterization of the eutrophication risk in the Zhejiang coastal waters under conditions of in situ uncertainty. The results showed that the level of the eutrophication index (EI) increased almost linearly with increasing threshold values; and that 71%, 51%, and 19% of coastal locations separated by various spatial lags experience considerable mesotrophic, eutrophic, and hypereutrophic risks, respectively. The average EI values over the subregions of the Zhejiang coastal waters graded as “oligotrophic or higher,” “eutrophic or higher,” and “hypereutrophic” were about 11.14, 14.28, and 25.34, respectively. Our results also revealed that the joint eutrophication strength between coastal locations in the Zhejiang region was consistently greater than the combined strength of independent eutrophications at these locations (we termed this situation “positive quadrant eutrophication dependency”). It was found that a critical eutrophication threshold ζcr ≈ 8.38 exists so that below ζcr the spatial eutrophication dependency in the Zhejiang coastal waters increases with ζ, whereas above ζcr the opposite is true. Moreover, the eutrophication dependency decreases as the separation distance δs increases. Interestingly, at distances δs smaller than a critical distance δscr ≈ 15  km, the eutrophication locations are concentrated in the coastal waters of the Zhejiang province rather than being dispersed (this observation holds even for large thresholds ζ). Elasticity analysis of eutrophication indicators offered a quantitative measure of the excess eutrophication change in the Zhejiang coastal waters caused by a threshold change (the larger the elasticity is, the more sensitive eutrophication is to threshold changes). The above findings can contribute to an improved understanding of seawater quality and provide a practical approach for the identification of critical coastal water regions.
Synthesis and Characterization of PEG‐PBS Copolymers to Obtain Microspheres With Different Naproxen Release Profiles
Authors: Ramon Jose , Saez Vivian , Gomes Fernando , Pinto Jose , Nele Marcio
Published: August 2018

Researching for new biomaterials intended for drug delivery systems has considerably intensified in recent years. There is an increasing interest in PBS (poly[butylene succinate]) and its copolymers as biomaterials due to the possibility of synthesis of the PBS from a renewable source. Among these copolymers, PBS‐PEG (poly[butylene succinate‐co‐polyethylene glycol]) is studied for materials that have shape memory and are biodegradable. However, to date, no research into the use of PBS‐PEG to prepare microspheres for drugs release has been reported. Herein, PBS‐PEGs with three PEG with different chain′s length were synthesized by polycondensation reaction and characterized by means of SEC, FTIR, DSC, TGA, and DRX. Naproxen loaded microspheres were prepared by an oil‐in‐water (o/w) single emulsion technique. The drug release was followed by UV‐Vis. The presence of PEG had a marked effect on the in vitro release profiles. The mathematical models employed show that the fundamental mechanism of release is diffusion when PEG is present in the polymer matrix of the particle.
Analysis of time‐domain elastic scattering by an unbounded structure
Authors: Gao Yixian , Li Peijun , Li Yong
Published: August 2018

This paper is devoted to the analysis of the time‐domain elastic wave scattering problem in an unbounded structure. The transparent boundary condition is developed to reformulate the scattering problem into an initial‐boundary value problem in an infinite slab. The well posedness and stability are established for the reduced problem in both the frequency and time domains. Our proofs are based on the energy method, the Lax‐Milgram theorem, and the inversion theorem of the Laplace transform. Moreover, a priori estimates with explicit dependence on the time are achieved for the elastic displacement by taking special test functions for the time‐domain variational problems of the Navier equation.
On k‐type null Cartan slant helices in Minkowski 3‐space
Authors: Nešović Emilija , Koç Öztürk Esra Betül , Öztürk Ufuk
Published: August 2018

In this paper, we define k‐type null Cartan slant helices lying on a timelike surface in Minkowski space
according to their Darboux frame, where k ∈ {0,1,2}. We study these helices by using their geodesic curvature, normal curvature , and geodesic torsion. Additionally, we determine their axes and consider the special cases when the mentioned helices are geodesic curves and principal curvature lines lying on the timelike surface in
. Furthermore, we obtain some interesting relations between 0‐, 1‐, and 2‐type null Cartan slant helices.
Influences of experimental parameters on chemical exchange saturation transfer (CEST) metrics of brain tumors using animal models at 4.7T
Authors: Heo Hye‐Young , Zhang Yi , Jiang Shanshan , Zhou Jinyuan
Published: August 2018

Purpose

To investigate the dependence of magnetization transfer ratio asymmetry at 3.5 ppm (MTRasym(3.5 ppm)), quantitative amide proton transfer (APT#), and nuclear Overhauser enhancement (NOE#) signals or contrasts on experimental imaging parameters.

Methods

Modified Bloch equation‐based simulations using 2‐pool and 5‐pool exchange models and in vivo rat brain tumor experiments at 4.7T were performed with varied RF saturation power levels, saturation lengths, and relaxation delays. The MTRasym(3.5 ppm), APT#, and NOE# contrasts between tumor and normal tissues were compared among different experimental parameters.

Results

The MTRasym(3.5 ppm) image contrasts between tumor and normal tissues initially increased with the RF saturation length, and the maxima occurred at 1.6−2 s under relatively high RF saturation powers (>2.1 μT) and at a longer saturation length under relatively low RF saturation powers (<1.3 μT). The APT# contrasts also increased with the RF saturation length but peaked at longer RF saturation lengths relative to MTRasym(3.5 ppm). The NOE# contrasts were either positive or negative, depending on the experimental parameters applied.

Conclusion

Tumor MTRasym(3.5 ppm), APT#, and NOE# contrasts can be maximized at different saturation parameters. The maximum MTRasym(3.5 ppm) contrast can be obtained with a relatively longer RF saturation length (several seconds) at a relatively lower RF saturation power.
Vangl2, a planar cell polarity molecule, is implicated in irreversible and reversible kidney glomerular injury
Authors: Papakrivopoulou Eugenia , Vasilopoulou Elisavet , Lindenmeyer Maja T , Pacheco Sabrina , Brzóska Hortensja Ł , Price Karen L , Kolatsi‐Joannou Maria , White Kathryn E , Henderson Deborah J , Dean Charlotte H , Cohen Clemens D , Salama Alan D , Woolf Adrian S , Long David A
Published: August 2018

Planar cell polarity (PCP) pathways control the orientation and alignment of epithelial cells within tissues. Van Gogh‐like 2 (Vangl2) is a key PCP protein that is required for the normal differentiation of kidney glomeruli and tubules. Vangl2 has also been implicated in modifying the course of acquired glomerular disease, and here, we further explored how Vangl2 impacts on glomerular pathobiology in this context. Targeted genetic deletion of Vangl2 in mouse glomerular epithelial podocytes enhanced the severity of not only irreversible accelerated nephrotoxic nephritis but also lipopolysaccharide‐induced reversible glomerular damage. In each proteinuric model, genetic deletion of Vangl2 in podocytes was associated with an increased ratio of active‐MMP9 to inactive MMP9, an enzyme involved in tissue remodelling. In addition, by interrogating microarray data from two cohorts of renal patients, we report increased VANGL2 transcript levels in the glomeruli of individuals with focal segmental glomerulosclerosis, suggesting that the molecule may also be involved in certain human glomerular diseases. These observations support the conclusion that Vangl2 modulates glomerular injury, at least in part by acting as a brake on MMP9, a potentially harmful endogenous enzyme. © 2018 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of Pathological Society of Great Britain and Ireland.
Quantitative Characterization of Mixing in Multicomponent Nanoparticle Aggregates
Authors: Baric Valentin , Grossmann Henrike Katharina , Koch Wolfgang , Mädler Lutz
Published: August 2018

The application of nanosized multicomponent particles often requires tailored mixing characteristics. This involves mixing on primary particle level, on cluster level, or on aggregate level. This mixing is often evaluated qualitatively in 2D, based on image analyses. This work presents an approach to utilize the cluster size in combination with the heterogeneous coordination number as a quantitative measure for the mixing of clusters of more than three primary particles within nanosized aggregates in 3D. Therefore, nanoparticle aggregates formed by differently sized clusters are simulated and evaluated with respect to cluster size and coordination number. Subsequently, a method is introduced to generate 2D projections and mimic image analysis based on transmission electron microscopy images from flame‐made nanoparticles. This also includes the evaluation of the necessary visible area for each particle to be identified in the 2D image analysis. This leads to a correlation of the 2D projections and 3D simulations including a calibration to experimental data and enables the determination of a 3D heterogeneous coordination number and cluster size from 2D image analysis.
An amphipathic cyclic tetrapeptide scaffold containing halogenated β2,2‐amino acids with activity against multiresistant bacteria
Authors: Paulsen Marianne H. , Karlsen Eskil André , Ausbacher Dominik , Anderssen Trude , Bayer Annette , Ochtrop Philipp , Hedberg Christian , Haug Tor , Ericson Sollid Johanna U. , Strøm Morten B.
Published: August 2018

The present study describes the synthesis and biological studies of a small series of head‐to‐tail cyclic tetrapeptides of the general structure c(Lys‐β2,2‐Xaa‐Lys) containing one lipophilic β2,2‐amino acid and Lys, Gly, Ala, or Phe as the Xaa residue in the sequence. The peptides were investigated for antimicrobial activity against gram‐positive and gram‐negative reference strains and 30 multiresistant clinical isolates including strains with extended spectrum β‐lactamase—carbapenemase (ESBL‐CARBA) production. Toxicity was determined against human red blood cells. The most potent peptides showed high activity against the gram‐positive clinical isolates with minimum inhibitory concentrations of 4–8 μg/mL and low haemolytic activity. The combination of high antimicrobial activity and low toxicity shows that these cyclic tetrapeptides containing lipophilic β2,2‐amino acids form a valuable scaffold for designing novel antimicrobial agents.
Vacuum‐Evaporated ZnO Photoanode, Applied in Quantum Dot‐Sensitized Solar Cells (CdS‐CdSe)
Authors: Alvarado José Alberto , Luo Jun , Juarez Héctor , Pacio Mauricio , Cortes‐Santiago Avelino , Liang Lihua , Neale Zachary G. , Cao Guozhong
Published: August 2018

In this research, the application of vacuum‐evaporated nanostructured ZnO thin films as a photoanode and its use in quantum dot‐sensitized solar cells (QDSSCs) is reported. Quantum dots (CdS/CdSe) are deposited through successive ionic layer adsorption and reaction (SILAR) technique. Thirty nanometers average size ZnO nanoparticles synthesized from solution are used as a source, resultant thickness starts from 200 nm to 3 microns. Average size and crystal phase identification are done by XRD. Scanning electron microscopy (SEM), UV‐Vis, profilometer, and J–V are used to determine morphology, elemental composition, transmittance, band gap, thickness, and efficiency of the solar cell, respectively. Characterization of efficiency is carried out on different film thicknesses. A total efficiency of 1.25% is obtained for a specific film thickness under 1.5 AM.
A machine learning technique toward generating minimum energy structures of small boron clusters
Authors: Mitikiri Praveen , Jana Gourhari , Sural Shamik , Chattaraj Pratim K.
Published: August 2018

The search for a global minimum related to molecular electronic structure and chemical bonding has received wide attention based on some theoretical calculations at various levels of theory. Particle swarm optimization (PSO) algorithm and modified PSO have been used to predict the energetically stable/metastable states associated with a given chemical composition. Out of a variety of techniques such as genetic algorithm, basin hopping, simulated annealing, PSO, and so on, PSO is considered to be one of the most suitable methods due to its various advantages over others. We use a swarm‐intelligence based parallel code to improve a PSO algorithm in a multidimensional search space augmented by quantum chemical calculations on gas phase structures at 0 K without any symmetry constraint to obtain an optimal solution. Our currently employed code is interfaced with Gaussian software for single point energy calculations. The code developed here is shown to be efficient. Small population size (small cluster) in the multidimensional space is actually good enough to get better results with low computational cost than the typical larger population. But for larger systems also the analysis is possible. One can try with a large number of particles as well. We have also analyzed how arbitrary and random structures and the local minimum energy structures gravitate toward the target global minimum structure. At the same time, we compare our results with that obtained from other evolutionary techniques.
Robust H∞ control for uncertain switched nonlinear polynomial systems: Parameterization of controller approach
Authors: Zhu Huawei , Hou Xiaorong
Published: August 2018

This paper considers the global feedback exponential stabilization and L2 gain disturbance attenuation problems of the switched nonlinear polynomial systems with passive and nonpassive subsystems for any given average dwell time. In the existing result, it needs that there exists at least one open loop passive subsystem in the switched nonlinear system, which is unnecessary for the switched nonlinear polynomial system in this paper because the passivity of the subsystem can be obtained according to the passivity‐based feedback dissipative Hamiltonian realization. In addition, a parameterization of controller approach–based feedback exponential stabilization method of nonlinear polynomial system is described and utilized such that the Lyapunov function of the passive subsystem possesses the required decay rate to exponentially stabilize the switched nonlinear polynomial system. Comparing with the controller designed with the existing method, the obtained controller in this paper has much simpler structure and better performance. An example simulation is provided to illustrate the effectiveness of the proposed approach.
Distributed flocking for disturbed multiple unicycle systems under directed topologies
Authors: Li Ping , Xu Shengyuan , Zhang Baoyong , Chen Weimin , Zhang Zhengqiang
Published: August 2018

This paper investigates the flocking problem for multiple unicycle systems in the presence of heterogenous input disturbances under directed topologies. Adaptive compensators are employed to eliminate the effect of disturbances. Based on the constructed potential functions, a class of novel distributed dynamic control algorithms are designed to implement flocking with connectivity preservation and collision avoidance with strongly connected directed graphs. It is noted that the proposed controller has released the constraints for connectivity preservation by only maintaining a minimum strongly connected directed graph in the initial topology. With the proposed methodology, the initial graph is allowed to contain those edges at boundary distances. Two illustrative examples are presented to demonstrate the effectiveness of the actuator involved in this paper.
Consensus control of second‐order delayed multiagent systems with intrinsic dynamics and measurement noises
Authors: Zong Xiaofeng , Li Tao , Zhang Ji‐Feng
Published: August 2018

This paper studies the consensus control of second‐order multiagent systems with intrinsic dynamics based on delayed and noisy measurements, where the delays in the position and velocity measurements are allowed to be different. The nonlinear and linear intrinsic dynamics are considered, respectively. For the case with nonlinear dynamics, mean square and almost sure consensus conditions are established by applying the degenerate Lyapunov functional and stochastic stability theorems. For the delay‐free case with linear dynamics, appropriate Lyapunov functions are established to get some simple sufficient conditions for mean square and almost sure consensus, and necessary conditions for mean square consensus. It is shown that, with respect to the weighted average type control protocols, second‐order multiagent systems are kept mean square consentable under multiplicative measurement noises alone or intrinsic dynamics alone, but may become unconsentable due to the coexistence of multiplicative noises and intrinsic dynamics. These results are further extended to leader‐following multiagent systems.
Global finite‐time output stabilization of nonlinear systems with unknown measurement sensitivity
Authors: Zhang Jin‐Xi , Yang Guang‐Hong
Published: August 2018

This paper focuses on the output stabilization problem for a class of strict‐feedback systems with unknown nonlinear dynamics and unknown measurement sensitivity. The imprecise sensor measurements render the existing robust control approaches such as neuro or fuzzy control infeasible. A solution is provided in this paper by a feat of the concept of tuning functions and barrier Lyapunov functions (BLFs). Utilizing the modification capability of tuning functions, global stability is preserved. Exploiting the potential robustness of BLFs, the effect of unmodeled dynamics is counteracted under sensitivity errors. The combination of tuning functions with BLFs further leads to a distinct property that the real system output converges to an adjustable region in finite time. Compared with the existing results, the need for prior knowledge of system nonlinearities and measurement sensitivity is removed in this paper. Finally, simulation results illustrate the established theoretical findings.
Green Synthesis and Theoretical Study of β‐Amino Esters via PPh3‐Catalyzed Mannich Reaction
Authors: Hussain Mustafa , Liu Jianhui , Zhang Zhipeng , Hu Mengwei , Li Yang , Min Xiangting
Published: August 2018

A new, efficient and simple method was designed for the synthesis of novel β‐carbonyl ester derivatives by using the PPh3‐catalyzed one‐pot method, three‐component condensation from aryl amines, aryl aldehydes and dicarbonyl ester under solvent‐free conditions. The comparative results from syntheses under these conditions provide a very simple reaction procedure that produces excellent yields and high stereoselectivity, avoids column chromatographic separation and provides an easy aqueous work‐up compared with the conventional reaction. DFT calculations were utilized to confirm and understand the mechanism of the PPh3‐catalyzed Mannich reaction. Detailed analysis of the two‐reaction pathway and their energy difference proves the stereo‐selectivity effect of the Mannich reaction, favouring anti‐isomer formation.