bluuebunny/crossref_metadata_2025 huggingface dataset:
Concealed by darkness: How stand density can override the biodiversity benefits of mixed forests
Authors: Hedwall P.‐O. , Holmström E. , Lindbladh M. , Felton A.
Published: August 2019

Higher tree species richness often increases the diversity of other taxonomic groups and is promoted in many managed forest systems. The reason for the higher diversity is due to, for example, inter‐specific differences in resource filtering of the trees. Resource filtering also depends on the total density of the tree layer, but the interaction between tree species composition and density is, so far, unexplored. Likewise, few studies have addressed whether mixtures of tree species host higher diversity, or support higher productivity, of other taxa than monocultures of the same tree species. We use a gradient in overstory tree species composition, ranging from pure Norway spruce (Picea abies) to pure Birch (Betula sp.), combined with a gradient from open to closed forest, to assess the joint effects of tree species mixture and forest density on the understory vegetation. The cover and species richness of understory vascular plants increased with an increasing proportion of birch and decreased with increasing forest density, while the cover of bryophytes decreased with an increasing proportion of birch and increasing forest density. There were clear interactions between tree species composition and forest density; the decrease in vascular plants with forest density was stronger in forest dominated by spruce than in forests dominated by birch, and the positive effect of an increasing proportion of birch was smaller in dense than in open forests. There were no indications of mixed forests supporting a higher species richness or plant cover than any of the two monocultures. Additionally, few species (10%) showed tendencies toward a higher probability of occurrence in mixed forests, and most of these also occurred in open pure stands. Our results indicate a potential conflict between goals for diversified forests and increased biomass production, as the positive effects for understory vegetation from mixtures may be lost to concomitant increases in forest density. Furthermore, the limited number of species benefiting from mixtures per se indicates that similar biodiversity benefits for understory vegetation may be obtained at landscape levels from the increased use of broadleaf and lower‐density production stands, as from mixtures.
Supercapacitor performances of RuO2/MWCNT, RuO2/Fullerene nanocomposites
Authors: Ates Murat , Kuzgun Ozge , yıldırım Murat , Yoruk Ozan , Bayrak Yuksel
Published: August 2019

In this study, RuO2/Fullerene and RuO2/MWCNT nanocomposites were synthesized to use as an electroactive materials in symmetric supercapacitor device performances. The materials were examined via Fourier transform infrared spectroscopy‐attenuated total reflectance (FTIR‐ATR), thermo‐gravimetric analysis (TGA‐DTA), scanning electron microscopy‐energy dispersive X‐ray analysis (SEM‐EDX), cyclic voltammetry (CV), galvanostatic charge/discharge (GCD) and electrochemical impedance spectroscopy (EIS). The RuO2/MWCNT and RuO2/Fullerene nanocomposite electrodes show good electrochemical performances. For instance, the highest specific capacitance of RuO2/Fullerene and RuO2/MWCNT electrodes reaches Csp = 3895.11 and 1662.19 F/g at 1 mV/s within the potential range of 0.8 V in 1 M H2SO4 solution. RuO2/MWCNT and RuO2/Fullerene nanocomposites have good cycle stability ~100% specific capacitance at [RuO2]o/[MWCNT]o = 1:1; 2:1 and [RuO2]o/[Fullerene]o = 2:1, respectively. The different equivalent circuit models of LR1Q(C1R2) and LR1(Q1R2)(Q2R3) were used to interpret EIS data.
Tuning the demodulation frequency based on a normalized trajectory model for mobile underwater acoustic communications
Authors: Ahmad Abdel‐Mehsen , Barbeau Michel , Garcia‐Alfaro Joaquin , Kassem Jamil , Kranakis Evangelos
Published: August 2019

We have developed a demodulator for low data rate, asynchronous frame, and narrow bandwidth underwater acoustic communication. We aim at operation under harsh conditions, ie, low signal‐to‐noise ratio, and across long distances. In this paper, we pay a special attention to the efficiency of mobility support. Mobility results into the Doppler effect, which, for a demodulator, makes the carrier frequency drift arbitrarily during attempts to decode frames. The chances of success are better when the demodulator can tune into the drifted carrier frequency. This can be achieved by trying a range of possible drifted carriers. We introduce the novel idea of normalized trajectory. Each normalized trajectory produces a unique Doppler shift pattern that can be applied to tune into a drifted carrier. We demonstrate that this improvement is theoretically sound. From a practical point of view, the search space is potentially reduced. The actual gain in performance is application‐specific and depends on the actual sets of trajectory parameters that are considered. We introduce the concept of normalized trajectory, discuss its integration into the demodulator, and review the performance of the new design.
A survey on access control mechanisms for cloud computing
Authors: El Sibai Rayane , Gemayel Nader , Bou Abdo Jacques , Demerjian Jacques
Published: August 2019

Cloud computing is an Internet‐based computing where the information technology resources are provided to end users following their request. With this technology, users and businesses can access programs, storage, and application development platforms through the Internet and via the services offered by the cloud service providers (CSPs). One of the biggest obstructions in the cloud computing environment is data security. Actually, the data are dispersed across multiple machines and storage devices such as servers, computers, and various mobile devices. The uncontrolled access to these resources and data leads to many important data security risks for the end users. In this way, and in order to ensure the reliability of the cloud and the trust of the users regarding this environment, controlling access to data and resources as well as protecting and ensuring their security becomes a critical task for CSPs. In this work, we present a comprehensive review of existing access control mechanisms used in the cloud computing environment. The advantages and disadvantages of each of these models are discussed and presented along with their analysis. Also, we study the cloud requirements of these models, and we evaluate existing control mechanisms against these requirements.
Endogenous opioid dependence after intermittent use of glucose, sodium chloride, and monosodium glutamate solutions
Authors: Sudakov Sergey K. , Bogdanova Natalia G. , Alekseeva Elena V. , Nazarova Galina A.
Published: August 2019

In 2002, Colantuoni et al described the possibility of dependency in rats after intermittent, excessive consumption of a 25% glucose solution over a one‐week period. We hypothesized that the intermittent consumption of any tasty solution can lead to endogenous opioid dependency. Another aim was to determine whether dependency is connected to the taste of the consumed substance or with its physiological significance. Rats were maintained on chow and cyclic glucose, NaCl, or monosodium glutamate (MSG) solution for 8 days. On day 9, after a 12‐hr deprivation period and administration of intraperitoneally (IP) naloxone, the general withdrawal index was calculated as the sum of teeth chattering, head shaking, forepaw tremors, and wet dog shakes. Motor activity was also documented. After the intermittent consumption of any tasty solution, rats were found to demonstrate signs of endogenous opioid dependence. The development of dependence was not related to taste preferences or the amount of solution consumed. Intermittent use of essential substance with a pleasant taste, as glucose and sodium chloride, leads to the rapid development of endogenous opioid dependence. Withdrawal syndrome following the consumption of MSG solution is associated with the presence of sodium ions in the MSG molecule.
The Pleistocene geoarchaeology and geochronology of Con Moong Cave, North Vietnam: Site formation processes and hominin activity in the humid tropics
Authors: McAdams Conor , Morley Mike W. , Fu Xiao , Kandyba Alexander V. , Derevianko Anatoly P. , Nguyen Dong T. , Doi Nguyen G. , Roberts Richard G.
Published: August 2019

This paper presents the results of geoarchaeological and geochronological investigations at Con Moong Cave, North Vietnam. Beneath the published, terminal Pleistocene sequence, recent excavations have uncovered a ~5 m stratigraphic sequence containing flaked stone artifacts and sedimentary features that indicate extensive post‐depositional change. As the effects of tropical conditions on Pleistocene cave sediments are poorly resolved, a range of complementary techniques was selected to reconstruct the nature of on‐site sedimentation and occupation, while assessing the taphonomy of archaeological and palaeoecological materials. Our approach incorporates microstratigraphic, geochemical and sedimentological analyses, using optically stimulated luminescence (OSL) dating to estimate the time of sediment deposition in the cave. This case study has broad application to tropical zones worldwide. Sedimentation began in early Marine Isotope Stage (MIS) 4, while micromorphologically observed human occupation commenced before 42 thousand years ago (ka). By placing our results within the context of published, high‐resolution regional records of climate, we demonstrate that on‐site rhythms of Pleistocene occupation correlated with environmental changes in the region. During MIS 3, episodic abandonment of the site coincided with periods of drier conditions, while rapid climate fluctuations in MIS 2 corresponded with short‐lived occupation events and a switch to predominantly geogenic deposition in the cave.
Could oxalate‐extractable phosphorus replace phosphorus fractionation schemes in soil phosphorus prospections?—A case study in the prehistoric Milseburg hillfort (Germany)
Authors: Weihrauch Christoph , Schupp Alexander , Söder Ulrike , Opp Christian
Published: August 2019

A geoarchaeological soil phosphorus (P) prospection is used to identify a gate within the prehistoric rampart of the Milseburg hillfort (Hesse, Germany). This study compares the application of a P fractionation scheme and P extraction with ammonium‐oxalate. We hypothesized that oxalate‐extractable P (P‐ox) and the related degree of P saturation (DPS) could replace the more expensive and time‐consuming fractionation schemes for geoarchaeological investigations. Comparing the results, the P fractionation helped to verify the existence of another section of the prehistoric ramparts and to identify the location of a gate within it. It also helped to discover the archaeologically relevant soil depths in the investigated area. This information could not be retrieved from the P‐ox data alone. Soil P‐ox contents and DPS values are relatively unspecific with regard to prehistoric land use. However, DPS at least indicates settled versus unsettled areas. Still, the results of the P fractionation more clearly delineate Iron Age land use areas including settlement, non‐settlement, rampart, and rampart gap (probable gate). Thus, in geoarchaeological contexts, this method seems to be preferable to a singular P‐ox extraction. However, for better results, P‐ox determination could be integrated into a P fractionation scheme.
The impact of treatment package time on locoregional control for HPV+ oropharyngeal squamous cell carcinoma treated with surgery and postoperative (chemo)radiation
Authors: Chao Hann‐Hsiang , Schonewolf Caitlin A. , Tan Erik X. , Swisher‐McClure Samuel , Ghiam Alireza F. , Weinstein Gregory S. , O'Malley Bert W. , Chalian Ara A. , Rassekh Christopher H. , Newman Jason G. , Cohen Roger B. , Bauml Joshua M. , Aggarwal Charu , Lin Alexander , Lukens John N.
Published: August 2019

Background

For patients with head and neck squamous cell carcinoma (SCC) undergoing surgery followed by postoperative radiotherapy (PORT), time from surgery to completion of adjuvant therapy, “package time” impacts locoregional control (LRC). However, the significance of package time in HPV+ oropharyngeal SCC (OPSCC) is unknown.

Methods

We examined patients undergoing TORS resection with PORT for HPV+ OPSCC from January 2010 to December 2015 with ≥18 months follow‐up (n = 267). A cutoff of 15 weeks was used to delineate patients into short and long package time groups. LRC loss was defined as any recurrence after surgery.

Results

Prolonged package time >15 weeks was associated with inferior LRC in this HPV+ OPSCC cohort, driven primarily by interval from surgery to PORT initiation. Multivariate analysis showed that package time and T classification are both independently associated with LRC.

Conclusions

Among HPV+ OPSCC, prolongation of package time appears to compromise LRC, but not survival.
Taba: A Tool to Analyze the Binding Affinity
Authors: da Silva Amauri Duarte , Bitencourt‐Ferreira Gabriela , de Azevedo Walter Filgueira
Published: August 2019

Evaluation of ligand‐binding affinity using the atomic coordinates of a protein‐ligand complex is a challenge from the computational point of view. The availability of crystallographic structures of complexes with binding affinity data opens the possibility to create machine‐learning models targeted to a specific protein system. Here, we describe a new methodology that combines a mass‐spring system approach with supervised machine‐learning techniques to predict the binding affinity of protein‐ligand complexes. The combination of these techniques allows exploring the scoring function space, generating a model targeted to a protein system of interest. The new model shows superior predictive performance when compared with classical scoring functions implemented in the programs Molegro Virtual Docker, AutoDock4, and AutoDock Vina. We implemented this methodology in a new program named Taba. Taba is implemented in Python and available to download under the GNU license at https://github.com/azevedolab/taba. © 2019 Wiley Periodicals, Inc.
Prognostic factors and survival in MEN1 patients with gastrinomas: Results from the DutchMEN study group (DMSG)
Authors: van Beek Dirk‐Jan , Nell Sjoerd , Pieterman Carolina R.C. , de Herder Wouter W. , van de Ven Annenienke C. , Dekkers Olaf M. , van der Horst‐Schrivers Anouk N. , Drent Madeleine L. , Bisschop Peter H. , Havekes Bas , Borel Rinkes Inne H. M. , Vriens Menno R. , Valk Gerlof D.
Published: August 2019

Background and objectives

Gastrinomas are the most prevalent functioning neuroendocrine tumors (NET) in multiple endocrine neoplasia type 1 (MEN1). Guidelines suggest medical therapy in most patients, but surgery may be considered in a subgroup. Currently, factors to guide management are necessary. This population‐based cohort study assessed prognostic factors of survival in patients with MEN1‐related gastrinomas.

Methods

Patients with MEN1 having gastrinomas were identified in the Dutch MEN1 database from 1990 to 2014 based on fasting serum gastrin (FSG) levels and/or pathology. Predictors of overall survival were assessed using Cox regression.

Results

Sixty‐three patients with gastrinoma (16% of the MEN1 population) were identified. Five‐ and 10‐year overall survival rates were 83% and 65%, respectively. Prognostic factors associated with overall survival were initial FSG levels ≥20x upper limit of normal (ULN) (hazard ratio [HR], 6.2 [95% confidence interval, 1.7‐23.0]), pancreatic NET ≥2 cm (HR 4.5; [1.5‐13.1]), synchronous liver metastases (HR 8.9; [2.1‐36.7]), gastroduodenoscopy suspicious for gastric NETs (HR 12.7; [1.4‐115.6]), and multiple concurrent NETs (HR 5.9; [1.2‐27.7]).

Conclusion

Life expectancy of patients with MEN1 gastrinoma is reduced. FSG levels and pancreatic NETs ≥2 cm are prognostic factors. FSG levels might guide surveillance intensity, step‐up to additional diagnostics, or provide arguments in selecting patients who might benefit from surgery.
Discordance in prediction of prognosis among patients with intrahepatic cholangiocarcinoma: A preoperative vs postoperative perspective
Authors: Moro Amika , Paredes Anghela Z. , Farooq Ayesha , Sahara Kota , Tsilimigras Diamantis I. , Mehta Rittal , Endo Itaru , Guglielmi Alfredo , Aldrighetti Luca , Alexandrescu Sorin , Marques Hugo P. , Shen Feng , Koerkamp Bas G. , Sasaki Kazunari , Pawlik Timothy M. ,   other members of the International Intrahepatic Cholangiocarcinoma Study Group
Published: August 2019

Background

The objective of the current study was to characterize patients with intrahepatic cholangiocarcinoma (ICC) undergoing curative‐intent surgery with discordant preoperative and postoperative prediction scores and determine factors associated with prediction discrepancy.

Methods

Patients who underwent hepatectomy for ICC between 1990 and 2016 were identified in a multi‐institutional international database. Preoperative and postoperative prognostic models were designed and discordant prognostic scores were identified. A multivariable logistic regression analysis was completed to determined factors associated with score discordance.

Results

Among 1149 patients, those who had concordant prediction scores were older (median age, 60 vs 56), and more likely to have a smaller median tumor size (6.0 vs 7.5 cm) (all P < .05). On multivariable logistic analysis, patients with higher neutrophil‐lymphocyte ratio (odds ratio [OR], 1.14; 95% confidence interval [CI], 1.09‐1.19), higher CEA levels (OR, 1.25; 95% CI, 1.04‐1.50), larger tumors (OR, 1.10; 95% CI, 1.04‐1.15) and suspicious lymph nodes (OR, 2.05; 95% CI, 1.25‐3.36) were more likely to have preoperative and postoperative score discordance. Older patients had decreased odds of having score discordance (OR, 0.98; 95% CI, 0.96‐0.99). Patients with score discordance had worse overall survival compared with patients with concordant scores (median:15.9 vs 21.7 months, P < .05).

Conclusion

Score discordance may reflect an aggressive variant of ICC that would benefit from early integration of multidisciplinary treatment strategies.
Duodenal GI stromal tumors: Is radical resection necessary?
Authors: Uppal Abhineet , Wang Mansen , Fischer Trevan , Goldfarb Melanie
Published: August 2019

Background and Objectives

Duodenal gastrointestinal stromal tumors (GISTs) are rare tumors that pose a surgical challenge, and long‐term outcomes after resection have not been detailed outside of small case series. This study uses the National Cancer Database (NCDB) to examine the determinants of radical resection for duodenal GISTs as well as the impact of local vs radical resection on overall survival (OS).

Methods

The NCDB was queried for nonmetastatic duodenal GISTs from 2004 to 2014. Predictors of radical resection were determined using multivariate logistic regression stratified by extent of tumor involvement. Factors associated with OS were identified with Cox proportional regression analysis.

Results

Treatment at an academic center, size >5 cm, and extra‐duodenal extension were associated with radical resection. On multivariate analysis, radical resection was associated with decreased OS (HR, 1.93; P < .03). Systemic therapy, extra‐duodenal extension, grade, stage, mitoses, and receipt of systemic therapy did not impact OS.

Conclusion

Local resection of duodenal GISTs is associated with improved OS compared to radical resection after controlling for tumor factors and systemic treatment. Traditional indicators of tumor aggressiveness were associated with radical resection, but not OS. When feasible, local resection should be considered for resection of duodenal GISTs.
Are authentic tourists happier? Examining structural relationships amongst perceived cultural distance, existential authenticity, and wellbeing
Authors: Yu Jibin , Li Hanliang , Xiao Honggen
Published: August 2019

The existential authenticity theory and eudaimonism theory imply that perceived cultural distance facilitates existential authenticity, which then conduces to hedonic and eudaimonic wellbeing. This study examined these presumptions basing on quantitative data collected through questionnaire survey in China. Results suggest that perceived cultural distance is not related to existential authenticity, and existential authenticity is positively related to hedonic and eudaimonic wellbeing. Hence, physically breaking away from one's home culture does not guarantee existential authenticity, and experiencing greater existential authenticity is related to correspondingly greater hedonic and eudaimonic wellbeing. Theoretical and practical implications of this research are also discussed.
Can fear be eaten? The emotional outcomes of consuming frightening foods or drinks
Authors: Du Jiangang , Zheng Qiuying , Hui Michael K. , Fan Xiucheng
Published: August 2019

This paper examines the emotional effects of consuming frightening foods or drinks. We argue that in addition to maintaining energy homeostasis and attaining pleasure, a third possible benefit of eating is the enhancement of perceived mastery over that which is eaten. Hence, the intake of frightening foods or drinks should increase a consumer's self‐confidence in dealing with fear. The findings of our three experimental studies confirm our counterintuitive predictions, namely that consuming frightening (vs. nonfrightening) foods or drinks leads to a significant reduction of fears arising from prior experiences of frightening activities and a significant increase in tolerance of prospective frightening activities. In addition, self‐confidence in dealing with fear is shown to significantly mediate the predicted effects of consuming frightening foods or drinks.
Single Crystals of V‐Amylose Complexed with Bicyclic Organic Compounds
Authors: Le Cong‐Anh‐Khanh , Choisnard Luc , Wouessidjewe Denis , Putaux Jean‐Luc
Published: August 2019

Lamellar single crystals of V‐amylose were prepared from dilute aqueous solutions in the presence of selected bicyclic compounds. Transmission electron microscopy images as well as electron and X‐ray diffraction patterns revealed that two allomorphs containing 7‐fold amylose single helices were formed depending on the complexing agent. On the one hand, trans‐decalin and (−)‐β‐pinene induced the crystallization of an orthorhombic unit cell isomorphous to that of V2‐propanol crystals reported in the literature (referred to as V7II). On the other hand, (+)‐camphor and (−)‐borneol yielded a new compact pseudo‐hexagonal structure (referred to as V7I). Cis‐decahydro‐1‐naphthol and decahydro‐2‐naphthol induced the formation of both allomorphs. V7I was favored at a higher crystallization temperature compared to V7II. Upon drying in vacuum, both V7I and V7II converted into the hexagonal anhydrous allomorph V7a but the initial structures were recovered by rewetting the crystals in water at room temperature. In addition, washing the crystals with methanol resulted in a transition from a 7‐fold to a 6‐fold helical conformation of amylose. The results suggest that both water and complexing agent play an important role on the formation and stability of V‐amylose crystals.
The marketing firm and co‐creation: An empirical study of marketer and customer's co‐creation process
Authors: Fagerstrøm Asle , Bendheim Liv Marie , Sigurdsson Valdimar , Pawar Sanchit , Foxall Gordon R.
Published: August 2019

This study empirically investigates the marketer and customer's co‐creation process within the context of the marketing firm. Based on principles from bilateral contingencies, findings from a conjoint study (n = 98) indicate that utilitarian and informational reinforcing consequences from the marketer have a stronger impact on customers' co‐creation behavior relative to informational reinforcing consequences from other customers. Consequently, analyzing the impact of important reinforcing contingencies through the lens of bilateral contingencies expands our understanding of how and why co‐creation outcomes might occur. Also, a good co‐creation process may increase the business companies' research and intelligence and, as a consequence, strengthen their competitiveness.
A de novo variant in the X‐linked gene CNKSR2 is associated with seizures and mild intellectual disability in a female patient
Authors: Polla Daniel L. , Saunders Harriet R. , de Vries Bert B. A. , van Bokhoven Hans , de Brouwer Arjan P. M.
Published: August 2019

Background

Eight different deletions and point variants of the X‐chromosomal gene CNKSR2 have been reported in families with males presenting intellectual disability (ID) and epilepsy. Obligate carrier females with a frameshift variant in the N‐terminal protein coding part of CNKSR2 or with a deletion of the complete gene are not affected. Only for one C‐terminal nonsense variant, two carrier females were mildly affected by seizures without or with mild motor and language delay.

Methods

Exome sequencing was performed in one female child of a Dutch family, presenting seizures, mild ID, facial dysmorphisms, and abnormalities of the extremities. Potential causative variants were validated by Sanger sequencing. X‐chromosome‐inactivation (XCI) analysis was performed by methylation‐sensitive PCR and fragment‐length analysis of the androgen‐receptor CAG repeat polymorphism.

Results

We identified a de novo variant, c.2304G>A (p.(Trp768*)), in the C‐terminal protein coding part of the X‐chromosomal gene CNKSR2 in a female patient with seizures and mild ID. Sanger sequencing confirmed the presence of this nonsense variant. XCI analysis showed a mild skewing of X inactivation (20:80) in the blood of our patient. Our variant is the second C‐terminal–affecting CNKSR2 variant described in neurologically affected females.

Conclusion

Our results indicate that CNKSR2 nonsense variants in the C‐terminal coding part can result in ID with seizures in female variant carriers.
Natural course of Fabry disease with the p. Arg227Ter (p.R227*) mutation in Finland: Fast study
Authors: Pietilä‐Effati Päivi , Saarinen Jukka T. , Löyttyniemi Eliisa , Autio Reijo , Saarenhovi Maria , Haanpää Maria K. , Kantola Ilkka
Published: August 2019

Background

Fabry disease is caused by a deficient or an absent alfa‐galactosidase A activity and is an X‐linked disorder that results in organ damage and a shortened life span, especially in males. The severity of the disease depends on the type of mutation, gender, skewed X‐chromosome inactivation, and other still unknown factors.

Methods

In this article, we describe the natural course of a common classic Fabry disease mutation, p.Arg227Ter or p.R227*, in Finland.

Results

Four males and ten females belonged to two extended families. The mean age was 46 years (SD 18.4). Six patients (43%) had cardiac hypertrophy, three patients (21%) had ischemic stroke, and none had severe kidney dysfunction. Three patients had atrial fibrillation; two patients who had atrial fibrillation also had pacemakers. All males over 30 years of age had at least one of the following manifestations: cardiac hypertrophy, stroke, or proteinuria. In females, the severity of Fabry disease varied from classic multiorgan disease to a condition that mimicked the attenuated cardiac variant. No one was totally asymptomatic without any signs of Fabry disease. Cardiac magnetic resonance imaging was performed on nine of 14 patients was the most sensitive for detecting early cardiac manifestations. Five patients (55%) had late gadolinium enhancement‐positive segments.

Conclusion

Cardiac involvement should be effectively detected in females before considering them asymptomatic mutation carriers.
How vector feeding preference through an infectious host relates to the seasonal transmission rates in a mathematical vector‐host model
Authors: Caja Rivera Rocio Marilyn
Published: August 2019

Vector‐borne diseases, such as leishmaniasis, dengue, malaria, and yellow fever, transmitted by microparasites show periodic fluctuations in their prevalence. The novelty of this research is to assess the relationship between the vector feeding preference for an infectious host and the annual seasonal transmission through a vector‐host mathematical model. For the first time, numerical simulations illustrate that by increasing the vector feeding preference value in the transmission dynamics, periodic fluctuations accentuate and the endemic equilibrium average increases in vector and host populations. Moreover, increasing the vector feeding preference value, the amplitude strengthens for the infectious host and vector populations. This periodic behavior shows a similar pattern with the Peruvian incidence data from 2000 to 2016 for Andean cutaneous leishmaniasis provided by the Ministry of Health of Peru (MINSA). In addition, using the Floquet theory, the time average method and the linear operator method provides for the first time that the basic reproduction number
for a nonautonomous system depends explicitly on the vector feeding preference for the infectious host. The nonautonomous model system shows that
is a threshold parameter for the local stability of the disease‐free periodic solution. Therefore, the vector feeding preference is an important factor that should be considered and attended to for future research. Public and veterinary health in Peru and other countries should consider the vector feeding preference for specific host to vector control.
Solvability of the fractional Volterra‐Fredholm integro differential equation by hybridizable discontinuous Galerkin method
Authors: Fatih Karaaslan Mehmet
Published: August 2019

This article proves the existence and uniqueness of the solution obtained by the hybridizable discontinuous Galerkin (HDG) method of the fractional Volterra‐Fredholm integro differential equation. The method based on local solvers and transmission condition is applied to the equation using two auxiliary variables. The form of the equation is amenable for achieving the solvability criteria of the problem according to the HDG method. We also calculate a numerical solution of the problem whose exact solution is taken as a smooth or fractional function. This results in a tridiagonal, symmetric, and positive definite stiffness matrix.
Prunus Mahaleb Fruit Extract Prevents Chemically Induced Colitis and Enhances Mitochondrial Oxidative Metabolism via the Activation of the Nrf2 Pathway
Authors: Ferramosca Alessandra , Treppiccione Lucia , Di Giacomo Mariangela , Aufiero Vera Rotondi , Mazzarella Giuseppe , Maurano Francesco , Gerardi Carmela , Rossi Mauro , Zara Vincenzo , Mita Giovanni , Bergamo Paolo
Published: August 2019

Scope

Polyphenols exhibit their antioxidant activity downstream the activation of the nuclear factor erythroid 2‐related factor 2 pathway (Nrf2), but the connection between lipid metabolism and the Nrf2 pathway is still unknown. Flavonoid‐rich concentrated extract from Prunus mahaleb (mahaleb concentrated fruit extract; MCFE) may act on oxido‐reductive homeostasis and hepatic lipid metabolism via Nrf2.

Methods & Results

MCFE ability to enhance the activity of Nrf2‐mediated antioxidant/detoxifying enzymes is investigated in liver and colon of BALB/c mice. After a 4‐week supplementation, macroscopic, histological, and biochemical signs of colitis are examined in mouse colon pulsed with 5% (w/v) dextran sodium sulfate (DSS). Untreated or DSS‐supplemented mice are used as negative or positive control. MCFE effect on liver lipid metabolism and its possible link with the Nrf2 pathway is investigated.

MCFE intake increases antioxidant defenses in mice colon and its pretreatment blunts pathological signs of colitis, as compared to positive control. In the liver, the increase in antioxidant defenses is associated with enhanced oxidative metabolism and with higher levels of peroxisome proliferator‐activated receptor gamma coactivator 1‐alpha (PGC‐1α) and of hemeoxygenase‐1 (HO‐1), in comparison with negative controls.

Conclusion

Cytoprotective and hypolipidemic effect produced by MCFE intake results, at least in part, by the activation of the Nrf2 pathway.
Four element ultra‐wideband fractal multiple‐input multiple‐output antenna
Authors: Singhal Sarthak
Published: August 2019

A four elements fractal antenna for UWB multiple‐input multiple‐output (MIMO) applications is presented. Each element comprises three iterations of inner tapered rectangular radiator and rectangular notch loaded coplanar waveguide rectangular ground planes. A rotated “+”shaped rectangular strip pair is introduced to enhance the isolation between two diagonally opposite elements. This antenna is operating over a frequency spectrum of 4.8‐19.4 with an intra‐element isolation of more than 15 dB. In addition to good radiation characteristics, desirable values of diversity performance parameters are achieved.
Numerically obtained vortices in granular media
Authors: Kolymbas Dimitrios , Bathaeian Iman
Published: August 2019

With our meshfree numerical code SPARC (Soft PARticle Code), which is based on strong solutions of the equations of equilibrium, we were able to derive vortex patterns ("turbulence") in deformations hitherto believed to be homogeneous. The formation of such vortices demonstrates the nonuniqueness of the corresponding boundary value problem. We present some evidence that such vortices can be related with ptygmatic folds, which are observed in rock.
Emerging, and old, dilemmas for food security in Latin America
Authors: Espinosa‐Cristia Juan Felipe , Feregrino Jorge , Isla Pablo
Published: August 2019

The present text offers a summary of some of the crucial food security problems in Latin American (LA) countries. This region, like many others in the globe, confronts such as food safety difficulties. The summary offers also an analysis of some technologically based solutions for LA food security issues. As a general call, the present review article calls for a collaborative and transdisciplinary approach to think deeper about how to solve food security problems, putting the focus on enabling technologies within a context of social, market, and global trends to achieve food and nutritional security. The review is positioned far from techno‐optimisms and, at the same time, away from purely economic‐based solutions. Conversely, this review embraces the whole complexity that brings economy‐nature‐technology triad. Embracing such complex relationships between technology, nature and the socio‐economy aspects of food security LA issues. Such complexity also triggers a need for a solution that considers a renewed approach to sustainability in the whole food value chain from production to consumption. Sustainability in the value chain opens up a much‐needed approach to LA food security that broadens, and refresh, our understanding of this fundamental socio‐economic and technical phenomena.
Synergistic effect of bismuth oxide and mono‐component intumescent flame retardant on the flammability and smoke suppression properties of epoxy resins
Authors: Xu Zhisheng , Jia Hongyu , Yan Long , Chu Zhiyong , Zhou Huan
Published: August 2019

A novel mono‐component intumescent flame retardant named pentaerythritol phosphate melamine salt (PPMS)‐hybrid bismuth oxide (PPMS‐Bi2O3) was synthesized and carefully characterized by FTIR, 1H NMR, 31P NMR, SEM‐EDS, and TG analyses. Then, PPMS‐Bi2O3 was utilized as flame retardant for epoxy resins (EPs), and the thermal stability, flame retardancy, and smoke suppression properties of EP composites were investigated. TG results show that PPMS‐Bi2O3 is more conducive to enhance the thermal stability and char forming ability of EP composites compared with the same addition of PPMS or the mixture of PPMS and Bi2O3, and this positive effect is enhanced with the increasing Bi2O3 content. Cone calorimeter test reveals that the PPMS‐Bi2O3 can effectively reduce the heat release and smoke production in comparison with PPMS or the mixture of PPMS and Bi2O3 due to the formation of a more compact and intumescent char against fire, as judged by digital photographs and SEM images. EDS analysis indicates that the combination PPMS and Bi2O3 by hydrogen bonds promotes to generate more phosphorus‐rich and aromatization structures in the condensed phase that enhance the barrier effect and anti‐oxidation ability of the char, thus imparting higher flame retardant and smoke suppression efficiencies to EP composites.
Assessing the vulnerability of Australia’s urban forests to climate extremes
Authors: Esperon‐Rodriguez Manuel , Power Sally A. , Tjoelker Mark G. , Beaumont Linda J. , Burley Hugh , Caballero‐Rodriguez Dayenari , Rymer Paul D.
Published: August 2019

Societal Impact Statement

Urban forests are recognized for the multiple benefits they provide to city‐dwellers. However, climate change will affect tree species survival and persistence in urban ecosystems. Tree failures will cause economic losses and jeopardize the delivery of societal benefits. The impacts of climate change will depend on the species’ resilience and adaptive capacity, as well as management actions which may ameliorate some of the negative impacts. Here, we assessed the potential vulnerability of Australia's urban forests to climate extremes. Our results can be used for future urban planning aiming to incorporate species that are well‐adapted to the hotter, drier climates expected with climate change.

Summary

Urban forests (UFs) are recognized for the multiple benefits they provide to city‐dwellers. However, global climate change—particularly predicted increases in the frequency and intensity of heatwaves and drought—will affect tree species’ performance and survival in urban ecosystems.

Here, we assessed species composition and potential vulnerability of UFs in 22 Australian significant urban areas (SUAs) to heat and/or moisture stress. We quantified species’ realized climatic niches across their known distribution, and assessed the extent to which baseline climate in the SUAs where a particular species is planted fell within its niche. We used three environmental variables to group species based on their potential climate vulnerability.

UFs varied in species composition and climate vulnerability across the continent. In general, neither climate similarity nor geographical proximity were good predictors of species composition among UFs. Of 1,342 tree species assessed (68.4% natives), 53% were considered potentially vulnerable to heat and/or moisture stress in at least one city where they are currently planted.

Our results highlight the climate vulnerability of current plantings across Australian SUAs and can be used to direct future species selection that considers the species’ climate of origin and climatic niche. UF planning can incorporate species from SUAs with similar climates and with low vulnerability to contemporary, as well as future climate conditions. Species with high climate vulnerability, in contrast, may require more intensive management to avoid failure under future hotter, drier climate conditions.
Multidisciplinary Role of Mesoporous Silica Nanoparticles in Brain Regeneration and Cancers: From Crossing the Blood–Brain Barrier to Treatment
Authors: Mendiratta Shruti , Hussein Menna , Nasser Hebatallah A. , Ali Ahmed Atef Ahmed
Published: August 2019

Mesoporous silica nanoparticles (MSNs) have gained wide attention for their role in biomedicine and as drug delivery vehicles. Their structural tunability, high surface area, and easy functionalization impart significant advantages over conventional materials. In this Review, recent advances in the synthesis, drug delivery, and therapeutic roles of MSNs in the treatment of various neurodegenerative and neuroinflammatory diseases are presented. The intention is to understand how MSN formulations that are capable of encapsulating drug molecules can enhance drug delivery by overcoming the blood–brain barrier (BBB) mediated by specific transport processes. The composition and characteristics of the BBB, and how alterations are observed in neurodegenerative diseases including Alzheimer's, epilepsy, and intracerebral hemorrhage are reviewed. Finally, the factors affecting efficient delivery of MSNs into the brain are summarized, and their most promising functional outcomes are discussed.
The anti‐hepatitis B virus therapeutic potential of anthraquinones derived from Aloe vera
Authors: Parvez Mohammad K. , Al‐Dosari Mohammed S. , Alam Perwez , Rehman MdTabish , Alajmi Mohammed F. , Alqahtani Ali S.
Published: August 2019

Although the approved hepatitis B virus (HBV)‐polymerase inhibitors (e.g., lamivudine) often lead to drug‐resistance, several natural products have shown promising efficacies. Though Aloe vera (AV) gel and its constituents are shown inhibitors of many viruses, their anti‐HBV activity still remains elusive. We therefore, tested the anti‐HBV potential of AV extract and its anthraquinones in hepatoma cells, including molecular docking, high‐performance thin layer chromatography (HPTLC), and cytochrome P450 (CYP3A4) activation analyses. Our anti‐HBV assays (HBsAg/HBeAg Elisa) showed maximal inhibition of viral antigens production by aloe‐emodin (~83%) > chrysophanol (~62%) > aloin B (~61%) > AV extract (~37%) in HepG2.2.15 cells. Interestingly, the effect of aloe‐emodin was comparable with lamivudine (~86%). Moreover, sequential treatment with lamivudine (pulse) followed by aloe‐emodin (chase) enhanced the efficacy of monotherapy by ~12%. Docking (AutoDock Vina) of the anthraquinones indicated strong interactions with HBV‐polymerase residues that formed stable complexes with high Gibbs's free energy. Further, identification of aloe‐emodin and aloin B by validated HPTLC in AV extract strongly endorsed its anti‐HBV potential. In addition, our luciferase‐reporter gene assay of transfected HepG2 cells showed moderate induction of CYP3A4 by aloe‐emodin. In conclusion, this is the first report on anti‐HBV potential of AV–derived anthraquinones, possibly via HBV‐polymerase inhibition. Of these, although aloin B exhibits novel antiviral effect, aloe‐emodin appears as the most promising anti‐HBV natural drug with CYP3A4 activating property towards its enhanced therapeutic efficacy.
Molecular networking as a dereplication strategy for monitoring metabolites of natural product treated cancer cells
Authors: Gao Yi‐Ling , Wang Ying‐Jing , Chung Hsin‐Hsiang , Chen Ko‐Chien , Shen Tang‐Long , Hsu Cheng‐Chih
Published: August 2019

Rationale

Natural products have been great sources for drug discovery. However, the structures of natural products are diverse and difficult to elucidate. Cordyceps militaris is a parasitic fungus which usually grows on host insects. The metabolites of C. militaris have been reported to act as chemotherapeutic agents. In this study, we aimed for the structural elucidation of specialized metabolites derived from C. militaris, and the metabolic impact in leukemia cells.

Methods

We describe a liquid chromatography data‐dependent mass spectrometric platform combining tandem mass analysis and molecular networking. Leukemia cells treated with C. militaris extract and control groups were visualized in terms of their metabolic profiles using Global Natural Product Social (GNPS) molecular networking. By this method, we were able to elucidate the structures of metabolites from medicinal fungus extracts and cancer cells and then to recognize their changes in a semi‐quantitative manner.

Results

Using C. militaris and leukemia cells as examples, we found that approximately 100 new ion species were present in the treated leukemia cells, suggesting a highly altered metabolic profile. Specifically, based on the tandem mass spectral similarity, we proposed that cordycepin, a key fungus‐derived therapeutic agent known for its antitumor activity, was transformed into its methylthio form in leukemia cells.

Conclusions

The platform described provides an ability to investigate complex molecular interactions of natural products in mammalian cells. By incorporating tandem mass spectrometry and molecular networking, we were able to reveal the chemical modification of crude bioactive compounds, for example potential bioactive compounds which might be modified from cordycepin. We envision that such a mass spectrometry (MS)‐based workflow, combined with other metabolomics platforms, would enable much wider applicability to cell biology and be of great potential to pharmacological study as well as drug discovery.
Connections Between Reading Identities and Social Status in Early Childhood
Authors: Wagner Christopher J.
Published: August 2019

This study examines the relationship between early reading identities and social status in school contexts. Reading identities, or the ways that a child constructs the self as a reader across contexts and time, have been posited to be closely linked with social status. This single‐case study examines the reading identities and social status of one 4‐year‐old, multilingual child attending prekindergarten in a public school in a large northeastern U.S. city. Data include child‐centered interviews, naturalistic observations, a teacher interview, and a family questionnaire. Findings provide insights into how one child’s ability to gain recognition of his reading identities was context dependent and distinct from his social status in the classroom, and point to more complexity in how the early reading identities of multilingual children are connected to their social contexts.
Seroprevalence and characterization of Brucella species in cattle slaughtered at Gauteng abattoirs, South Africa
Authors: Kolo Francis B. , Adesiyun Abiodun A. , Fasina Folorunso O. , Katsande Charles T. , Dogonyaro Banenat B. , Potts Andrew , Matle Itumeleng , Gelaw Awoke K. , van Heerden Henriette
Published: August 2019

Background

Brucellosis is an infectious and contagious zoonotic bacterial disease of both humans and animals. In developing countries where brucellosis is endemic, baseline data on the prevalence of brucellosis, using abattoir facilities, is important.

Objectives

The aim of this study was to determine the seroprevalence of antibodies against Brucella in slaughter cattle at Gauteng province, South Africa and to characterize isolates of Brucella spp.

Methods

In this cross‐sectional study, un‐clotted blood samples with corresponding organ tissue samples were collected from slaughtered cattle. Serological [Rose Bengal test (RBT), complement fixation test (CFT) and indirect ELISA (iELISA)], molecular (PCR) and bacteriological methods were used to detect Brucella antibodies and Brucella spp. from 200 slaughtered cattle in 14 abattoirs.

Results

The RBT revealed a seroprevalence of brucellosis as 11.0% (22 of 200) and iELISA confirmed 5.5% (11 of 200). The estimated seroprevalence from RBT and iELISA was 5.5% while RBT and CFT was 2.0% (4 of 200). Brucella melitensis (n = 6) and B. abortus (n = 5) were isolated from 11 cattle tissues (5.5%) as confirmed to species level with AMOS PCR and differentiated from vaccine strains with Bruce‐ladder PCR. Seven of the 11 isolates originated from seropositive cattle of which five were biotyped as B. abortus bv 1 (n = 2) and B. melitensis bv 2 (n = 1) and B. melitensis bv 3 (n = 2).

Conclusions

This is the first documentation of B. melitensis in cattle in South Africa. The zoonotic risk of brucellosis posed by Brucella‐infected slaughter cattle to abattoir workers and consumers of improperly cooked beef cannot be ignored.