bluuebunny/crossref_metadata_2025_split huggingface dataset:
Hepatitis B Screening Profile, Epidemiological and Clinical Characteristics in a Highly Endemic Population in Southern Nigeria
Authors: Sarah Abere , Boma Oyan , Tonye-Abere Orabelema , Alali Aloni , Uzoaku Amadi 
Published: August 2024

Background: Viral hepatitis B is a life-threatening condition with global public health implications. It is highly endemic and one of the leading causes of mortality in Africa. There are no screening strategies defined for the general population in Nigeria despite an estimated 19 million Nigerians living with Hepatitis B, and a high prevalence of 11-13%.
This study aims to identify indications for Hepatitis B screening, as well as the virologic, radiologic and sociodemographic characteristics of this populace.
Methods: This is a cross-sectional review of the viral hepatitis database of Adult Hepatitis B positive patients. The biodata, laboratory and radiological parameters were analyzed using SPSS version 26 and Categorical variables were reported as frequencies and percentages. Continuous variables were reported as means ±SD, and a p-value of ≤0.05 was considered to be statistically significant.
Results: The mean age of the 454 hepatitis B positive patients was 38.33±11.16years comprising198(43.8%) females and 255(56.2%) males. All six geopolitical regions of Nigeria were represented in the study with the south-south region having the highest representation of 220 patients. Incidental findings such as pre-employment screening, pre-marriage screening, screening before blood donation, pre-surgery screening for non-Hepatic related diagnosis and public health awareness campaigns accounted for 64% of the indications for screening, 4.4% were diagnosed from the compulsory antenatal screening and 11.3% with advanced liver disease.
The majority of patients (94.7%) were HBeAg negative, while HBV DNA levels ranged from <20 to 170,500,000 IU/ml (mean=4,509,723.97 ± 26,264,722.07 IU/ml).
Increased AST and ALT levels were observed in 256 (56.4%) and 193 patients (42.5%) respectively while 22.2% of the study population had radiological evidence of hepatic disorders at initial screening.
Conclusion: This study revealed that Hepatitis B infection in Nigeria cuts across all regions and has a gender disparity with more males affected than females. The majority of the participants were diagnosed incidentally or during an illness, highlighting the importance of routine screening. Additionally, the majority of patients had HBeAg-negative chronic Hepatitis B, indicating the need for effective public health strategies to address this prevalent form of the disease.
Wind‐driven freshwater buildup and release in the Beaufort Gyre constrained by mesoscale eddies
Authors: Manucharyan Georgy E. , Spall Michael A. 
Published: October 2015

AbstractRecently, the Beaufort Gyre has accumulated over 20,000 km3 of freshwater in response to strong anticyclonic atmospheric winds that have prevailed over the gyre for almost two decades. Here we explore key physical processes affecting the accumulation and release of freshwater within an idealized eddy‐resolving model of the Beaufort Gyre. We demonstrate that a realistic halocline can be achieved when its deepening tendency due to Ekman pumping is counteracted by the cumulative action of mesoscale eddies. Based on this balance, we derive analytical scalings for the depth of the halocline and its spin‐up time scale and emphasize their explicit dependence on eddy dynamics. Our study further suggests that the Beaufort Gyre is currently in a state of high sensitivity to atmospheric winds. However, an intensification of surface stress would inevitably lead to a saturation of the freshwater content—a constraint inherently set by the intricacies of the mesoscale eddy dynamics.
Effect of sea‐ice melt on inherent optical properties and vertical distribution of solar radiant heating in Arctic surface waters
Authors: Granskog Mats A. , Pavlov Alexey K. , Sagan Sławomir , Kowalczuk Piotr , Raczkowska Anna , Stedmon Colin A. 
Published: October 2015

AbstractThe inherent optical properties (IOPs) of Polar Waters (PW) exiting the Arctic Ocean in the East Greenland Current (EGC) and of the inflowing Atlantic waters (AW) in the West Spitsbergen Current (WSC) were studied in late summer when surface freshening due to sea‐ice melt was widespread. The absorption and attenuation coefficients in PW were significantly higher than previous observations from the western Arctic. High concentrations of colored dissolved organic matter (CDOM) resulted in 50–60% more heat deposition in the upper meters relative to clearest natural waters. This demonstrates the influence of terrigenous organic material inputs on the optical properties of waters in the Eurasian basin. Sea‐ice melt in CDOM‐rich PW decreased CDOM absorption, but an increase in scattering nearly compensated for lower absorption, and total attenuation was nearly identical in the sea‐ice meltwater layer. This suggests a source of scattering material associated with sea‐ice melt, relative to the PW. In the AW, melting sea‐ice forms a stratified surface layer with lower absorption and attenuation, than well‐mixed AW waters in late summer. It is likely that phytoplankton in the surface layer influenced by sea‐ice melt are nutrient limited. The presence of a more transparent surface layer changes the vertical radiant heat absorption profile to greater depths in late summer both in EGC and WSC waters, shifting accumulation of solar heat to greater depths and thus this heat is not directly available for ice melt during periods of stratification.
Magnetism of a very young lunar glass
Authors: Buz Jennifer , Weiss Benjamin P. , Tikoo Sonia M. , Shuster David L. , Gattacceca Jérôme , Grove Timothy L. 
Published: October 2015

AbstractRecent paleomagnetic studies of Apollo samples have established that a core dynamo existed on the Moon from at least 4.2 to 3.56 billion years (Ga). Because there is no lunar dynamo today, a longstanding mystery has been the origin of magnetization in very young lunar samples (<~200 million years old (Ma)). Possible sources of this magnetization include transient fields generated by meteoroid impacts, remanent fields from nearby rocks magnetized during an earlier dynamo epoch, a weak late dynamo, and spontaneous remanence formed in a near‐zero field. To further understand the source of the magnetization in young lunar samples, we conducted paleomagnetic, petrographic, and 40Ar/39Ar geochronometry analyses on a young impact melt glass rind from the exterior of ~3.35 Ga mare basalt 12017. Cosmic ray track densities and our 40Ar/39Ar and cosmogenic 38Ar analyses constrain the glass formation age to be <7 Ma and most likely <20 thousand years (kyr), making it likely the youngest extraterrestrial sample yet studied with paleomagnetic methods. Despite its relatively high fidelity magnetic recording properties compared to most lunar rocks, we find that the glass carries no stable primary natural remanent magnetization and that it formed in a field <~7 μT (with a 2 σ upper limit of <11 μT). Given the poor magnetic recording properties of the majority of lunar samples, this provides further evidence that many or perhaps even all previous paleointensity estimates for ≤1.5 Ga rocks are upper limits on the true paleofield and therefore require neither a protracted strong (>10 μT) core dynamo field nor impact‐generated fields.
Enhanced Pain Sensitivity Among Individuals With Symptomatic Knee Osteoarthritis: Potential Sex Differences in Central Sensitization
Authors: Bartley Emily J. , King Christopher D. , Sibille Kimberly T. , Cruz‐Almeida Yenisel , Riley Joseph L. , Glover Toni L. , Goodin Burel R. , Sotolongo Adriana S. , Herbert Matthew S. , Bulls Hailey W. , Staud Roland , Fessler Barri J. , Redden David T. , Bradley Laurence A. , Fillingim Roger B. 
Published: October 2015

ObjectiveSymptomatic knee osteoarthritis (OA) is a condition commonly associated with increased pain, disability, and functional limitations. Given the poor correspondence between radiographic evidence and clinical pain, central sensitization has been implicated as a potential mechanism underlying pain facilitation in knee OA. Sex may be a moderator of centrally mediated changes in knee OA pain; however, few studies have systematically assessed this. Therefore, the aim of this study was to examine differences in peripheral and central sensitization in men and women with symptomatic knee OA, as well as to determine whether these differences vary across age (middle age versus older age).MethodsParticipants (n = 288) between the ages of 45 and 85 years completed a battery of quantitative sensory pain procedures assessing sensitivity to contact heat, cold pressor, mechanical pressure, and punctate stimuli. Differences in temporal summation (TS) were examined, as well as measures of clinical pain and functional performance.ResultsWhen compared to men, women exhibited greater sensitivity to multiple pain modalities (i.e., lower heat, cold, pressure thresholds/tolerances, greater TS of pain); however, there were no sex differences in clinical pain, with the exception of greater widespread pain observed in women. Although there were select age‐related differences in pain sensitivity, sex differences in pain varied minimally across the age cohort.ConclusionOverall, these findings provide evidence for greater overall sensitivity to experimental pain in women with symptomatic knee OA compared to men, suggesting that enhanced central sensitivity may be an important contributor to pain in this group.
Approximate optimal adaptive control for weakly coupled nonlinear systems: A neuro‐inspired approach
Authors: García Carrillo Luis Rodolfo , Vamvoudakis Kyriakos G. , Hespanha João Pedro 
Published: October 2015

SummaryThis paper proposes a new approximate dynamic programming algorithm to solve the infinite‐horizon optimal control problem for weakly coupled nonlinear systems. The algorithm is implemented as a three‐critic/four‐actor approximators structure, where the critic approximators are used to learn the optimal costs, while the actor approximators are used to learn the optimal control policies. Simultaneous continuous‐time adaptation of both critic and actor approximators is implemented, a method commonly known as synchronous policy iteration. The adaptive control nature of the algorithm requires a persistence of excitation condition to be a priori guaranteed, but this can be relaxed by using previously stored data concurrently with current data in the update of the critic approximators. Appropriate robustifying terms are added to the controllers to eliminate the effects of the residual errors, leading to asymptotic stability of the equilibrium point of the closed‐loop system. Simulation results show the effectiveness of the proposed approach for a sixth‐order dynamical example. Copyright © 2015 John Wiley & Sons, Ltd.
Kopieren von RNA‐Sequenzen ohne Voraktivierung
Authors: Jauker Mario , Griesser Helmut , Richert Clemens 
Published: October 2015

AbstractDer templatgesteuerte Einbau von Nukleotiden am Terminus eines Komplementärstrangs ist die Grundlage der Replikation. Im Fall von RNA kann dieser Vorgang in Abwesenheit von Enzymen stattfinden, wenn die Ribonukleotide vorher in eine Aktivspezies mit einer Abgangsgruppe überführt werden. Bisher war für diese Aktivierung ein separater chemischer Schritt nötig, was komplizierte präbiotisch plausible Szenarios erfordert. Wir zeigen nun, dass die Kombination eines Carbodiimids und eines Organokatalysators den annähernd quantitativen Einbau jedes der vier Ribonukleotide induziert. Bei In‐situ‐Aktivierung von Adenosinmonophosphat bilden sich gleichzeitig Oligomere in wässriger Lösung. Es können also Strangbildung und sequenzspezifische Kopiervorgänge ohne künstlichen Syntheseschritt stattfinden.
Silica Nanowires Templated by Amyloid‐like Fibrils
Authors: Al‐Garawi Zahraa S. , Thorpe Julian R. , Serpell Louise C. 
Published: October 2015

AbstractMany peptides self‐assemble to form amyloid fibrils. We previously explored the sequence propensity to form amyloid using variants of a designed peptide with sequence KFFEAAAKKFFE. These variant peptides form highly stable amyloid fibrils with varied lateral assembly and are ideal to template further assembly of non‐proteinaceous material. Herein, we show that the fibrils formed by peptide variants can be coated with a layer of silica to produce silica nanowires using tetraethyl‐orthosilicate. The resulting nanowires were characterized using electron microscopy (TEM), X‐ray fiber diffraction, FTIR and cross‐section EM to reveal a nanostructure with peptidic core. Lysine residues play a role in templating the formation of silica on the fibril surface and, using this library of peptides, we have explored the contributions of lysine as well as arginine to silica templating, and find that sequence plays an important role in determining the physical nature and structure of the resulting nanowires.
Characterization of 3D elastic porous polydimethylsiloxane (PDMS) cell scaffolds fabricated by VARTM and particle leaching
Authors: Si Junhui , Cui Zhixiang , Xie Peng , Song Lairui , Wang Qianting , Liu Qiong , Liu Chuntai 
Published: October 2015

ABSTRACTIn this study, elastic porous polydimethylsiloxane (PDMS) cell scaffolds were fabricated by vacuum‐assisted resin transfer moulding (VARTM) and particle leaching technologies. To control the porous morphology and porosity, different processing parameters, such as compression load, compression time, and NaCl particle size for preparing NaCl preform, were studied. The porous structures of PDMS cell scaffolds were characterized by scanning electron microscopy (SEM). The properties of PDMS cell scaffolds, including porosity, water absorption, interconnectivity, compression modulus, and compression strength were also investigated. The results showed that after the porogen–NaCl particles had been leached, the remaining pores had the sizes of 150–300, 300–450, and 450–600 μm, which matched the sizes of the NaCl particles. The interconnectivity of PDMS cell scaffolds increases with an increase in the size of NaCl particles. It was also found that the smaller the size of the NaCl particles, the higher the porosity and water absorption of PDMS cell scaffolds. The content of residual NaCl in PDMS/NaCl scaffolds reduces under ultrasonic treatment. In addition, PDMS scaffolds with a pore size of 300–450 μm have better mechanical properties compared to those with pore sizes of 150–300 and 450–600 μm. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 42909.
Hospital of diagnosis and likelihood of surgical treatment for pancreatic cancer
Authors: Bakens M J A M , van Gestel Y R B M , Bongers M , Besselink M G H , Dejong C H C , Molenaar I Q , Busch O R C , Lemmens V E P P , de Hingh I H J T 
Published: October 2015

Abstract

Background
Surgical resection for pancreatic cancer offers the only chance of cure. Assessment of the resectability of a pancreatic tumour is therefore of great importance. The aim of the study was to investigate whether centre of diagnosis influences the likelihood of surgery and whether this affects long-term survival.

Methods
Patients diagnosed with non-metastasized pancreatic cancer (M0) between 2005 and 2013 in the Netherlands were selected from the Netherlands Cancer Registry. Hospitals were classified as a pancreatic centre (at least 20 resections/year) or a non-pancreatic centre (fewer than 20 resections/year). The relationship between centre of diagnosis and likelihood of surgery was analysed by multivariable logistic regression. Influence of centre on overall survival was assessed by means of multivariable Cox regression analysis.

Results
Some 8141 patients were diagnosed with non-metastasized pancreatic cancer, of whom 3123 (38·4 per cent) underwent surgery. Of the 2712 patients diagnosed in one of 19 pancreatic centres, 52·4 per cent had exploratory laparotomy compared with 31·4 per cent of 5429 patients diagnosed in one of 74 non-pancreatic centres (P &lt; 0·001). A pancreatectomy was performed in 42·8 and 24·6 per cent of the patients respectively (P &lt; 0·001). Multivariable analysis revealed that patients diagnosed in a pancreatic centre had a higher chance of undergoing surgery (odds ratio 2·21, 95 per cent c.i. 1·98 to 2·47). Centre of diagnosis was not associated with improved long-term survival (hazard ratio 0·95, 95 per cent c.i. 0·91 to 1·00).

Conclusion
Patients with non-metastasized pancreatic cancer had a greater likelihood of having surgical treatment when the diagnosis was established in a pancreatic centre.
Making Dimethylamino a Transformable Directing Group by Nickel‐Catalyzed CN Borylation
Authors: Zhang Hua , Hagihara Shinya , Itami Kenichiro 
Published: October 2015

AbstractThe dimethylamino (Me2N) group is arguably the most versatile functional group capable of highly efficient and site‐selective directed aromatic functionalizations at the ortho‐, meta‐, and para‐positions depending on reaction conditions. While the repertoire of Me2N‐directed reactions is growing at a rapid pace, the lack of a general method to transform this group to other functionalities hampers its wider application in organic synthesis. Here we report nickel‐catalyzed CN borylations of aryl‐ and benzyl‐dimethylamines that permit the conversion of a huge library of largely underutilized Me2N‐containing organic molecules into various functional molecules by taking advantage of the wealth of existing CB functionalization methods.
Preparation of Pt‐B/Al2O3 amorphous alloy catalysts via microemulsion methods and application into hydrogenation of m‐chloronitrobenzene
Authors: Li Feng , Cao Bo , Ma Rui , Song Hualin , Song Hua 
Published: October 2015

AbstractPt‐B/Al2O3 catalysts were prepared through chemical reduction of platinum ions with borohydride in a water/oil (W/O) microemulsion system comprising cetyltrimethyl ammonium bromide (CTAB), n‐butanol, cyclohexane, and H2PtCl6 solution. Transmission electron microscope (TEM) and selected‐area electron diffraction (SAED) analyses show that the active Pt particles on the catalysts are uniformly distributed as a Pt‐B amorphous alloy. We studied the effects of microemulsion composition, reduction conditions, and preparation methods on the catalysts applied into m‐chloronitrobenzene (m‐CNB) hydrogenation. We also investigated the kinetics of m‐CNB hydrogenation. The catalyst prepared via a single‐microemulsion method exhibited much higher activity and even higher selectivity than that prepared with the aqueous solution method. Finally, we propose the mechanism for Pt‐B effects on the catalytic performance of Pt‐B/Al2O3 in m‐CNB hydrogenation.
Influence of drying temperature and atmosphere on the mechanical strength of iron‐ore agglomerates and sodium silicates for application in sintering processes
Authors: de Castro Dutra Flávio , Emrich Marcus , Magela da Costa Geraldo , Dias Anderson 
Published: October 2015

AbstractThis paper presents the influence of drying temperature and atmosphere on the mechanical strength of iron‐ore agglomerates and sodium silicates. Mixtures of different pellet feed and sodium silicates were produced with a ball disc and cured at various temperatures. The resulting products exhibited sufficiently high mechanical strength to be transported over long distances and handled until their use in sintering processes. The agglomerates were dried/cured at temperatures between 100–550 °C and in gaseous atmospheres consisting of air and/or carbon dioxide. During this process, a strong influence of both temperature and atmosphere on the compression strength after contact with water, as well as on the morphology of the sodium silicates, was observed. The use of carbon dioxide atmosphere during drying proved effective for achieving high mechanical strength after water immersion. A phenomenological approach was developed to explain the results in order to connect morphology and mechanical properties.
Fe(III) recovery from HCl solutions using amberlite XAD‐7 resin impregnated with a tetraalkyl phosphonium ionic liquid
Authors: Navarro Ricardo , Saucedo Imelda , Gallardo Violeta , Guibal Eric 
Published: October 2015

AbstractFe(III) is efficiently extracted from concentrated HCl solutions using Amberlite XAD‐7 impregnated with tetraalkyl phosphonium chloride ionic liquid (IL) (synthesis of extractant‐impregnated resin, EIR). The sorption efficiency is controlled by metal speciation and IL loading in the EIR. Sorption isotherms in mono‐component solutions are described by the Langmuir equation, while the extended Langmuir equation perfectly fits sorption isotherms from binary Fe(III)/Zn(II) solutions. The thermodynamic study confirms the endothermic nature of the sorption. Uptake kinetics are fitted by the pseudo‐second order rate equation. While temperature and metal concentration have a relatively limited effect on kinetics, the IL content more significantly affects the mass transfer of Fe(III). Water, sodium sulphate, nitric acid, and sulphuric acid almost completely desorb Fe(III) from loaded EIRs. Resin recycling was tested for eight cycles without significant decrease of the sorption and desorption efficiencies.
Aryl Bis‐Sulfonamide Inhibitors of IspF from Arabidopsis thaliana and Plasmodium falciparum
Authors: Thelemann Jonas , Illarionov Boris , Barylyuk Konstantin , Geist Julie , Kirchmair Johannes , Schneider Petra , Anthore Lucile , Root Katharina , Trapp Nils , Bacher Adelbert , Witschel Matthias , Zenobi Renato , Fischer Markus , Schneider Gisbert , Diederich François 
Published: October 2015

Abstract2‐Methylerythritol 2,4‐cyclodiphosphate synthase (IspF) is an essential enzyme for the biosynthesis of isoprenoid precursors in plants and many human pathogens. The protein is an attractive target for the development of anti‐infectives and herbicides. Using a photometric assay, a screen of 40 000 compounds on IspF from Arabidopsis thaliana afforded symmetrical aryl bis‐sulfonamides that inhibit IspF from A. thaliana (AtIspF) and Plasmodium falciparum (PfIspF) with IC50 values in the micromolar range. The ortho‐bis‐sulfonamide structural motif is essential for inhibitory activity. The best derivatives obtained by parallel synthesis showed IC50 values of 1.4 μm against PfIspF and 240 nm against AtIspF. Substantial herbicidal activity was observed at a dose of 2 kg ha−1. Molecular modeling studies served as the basis for an in silico search targeted at the discovery of novel, non‐symmetrical sulfonamide IspF inhibitors. The designed compounds were found to exhibit inhibitory activities in the double‐digit micromolar IC50 range.
Synthesis and Characterization of Chitosan‐Based Polyelectrolyte Complexes Doped with Xanthene Dyes
Authors: Slyusareva Evgenia , Gerasimova Marina , Slabko Vitaliy , Abuzova Nina , Plotnikov Alexei , Eychmüller Alexander 
Published: October 2015

AbstractBiocompatible chitosan‐based polyelectrolyte complexes (PECs) doped with xanthene dyes (fluorescein, eosin Y, erythrosin B, rhodamine 6G) were synthesized and characterized by scanning electron microscopy, dynamic light scattering, zeta potential measurements, and absorption and luminescence (including polarized, time‐resolved, and phosphorescence) spectroscopy. The results are discussed in terms of the mechanism and rigidity of dye–PEC binding, the heavy‐atom effect in dyes and PEC stability. Eosin Y is found to be the optimal dopant, providing both a high dye content in PECs and a high quantum yield of fluorescence.