bluuebunny/crossref_metadata_2025 huggingface dataset:
Inverse problem for a space‐time fractional diffusion equation: Application of fractional Sturm‐Liouville operator
Authors: Ali Muhammad , Aziz Sara , Malik Salman A.
Published: February 2018

An inverse problem of determining a time‐dependent source term from the total energy measurement of the system (the over‐specified condition) for a space‐time fractional diffusion equation is considered. The space‐time fractional diffusion equation is obtained from classical diffusion equation by replacing time derivative with fractional‐order time derivative and Sturm‐Liouville operator by fractional‐order Sturm‐Liouville operator. The existence and uniqueness results are proved by using eigenfunction expansion method. Several special cases are discussed, and particular examples are provided.
One‐level and two‐level finite element methods for the Boussinesq problem
Authors: Zhang Tong , Jiang Tao , Yuan JinYun
Published: February 2018

Previous works on the convergence of numerical methods for the Boussinesq problem were conducted, while the optimal L2‐norm error estimates for the velocity and temperature are still lacked. In this paper, the backward Euler scheme is used to discrete the time terms, standard Galerkin finite element method is adopted to approximate the variables. The MINI element is used to approximate the velocity and pressure, the temperature field is simulated by the linear polynomial. Under some restriction on the time step, we firstly present the optimal L2 error estimates of approximate solutions. Secondly, two‐level method based on Stokes iteration for the Boussinesq problem is developed and the corresponding convergence results are presented. By this method, the original problem is decoupled into two small linear subproblems. Compared with the standard Galerkin method, the two‐level method not only keeps good accuracy but also saves a lot of computational cost. Finally, some numerical examples are provided to support the established theoretical analysis.
Comparative Study of Different Polar Groups of EPA‐Enriched Phospholipids on Ameliorating Memory Loss and Cognitive Deficiency in Aged SAMP8 Mice
Authors: Zhou Miao‐miao , Che Hong‐xia , Huang Jia‐qi , Zhang Tian‐tian , Xu Jie , Xue Chang‐hu , Wang Yu‐ming
Published: February 2018

Scope

Recent studies have shown that omega‐3 PUFAs enriched phospholipids (n‐3 PUFA‐PLs) have beneficial effects on memory and cognition. However, most reports only attribute the benefit to docosahexaenoic acid (DHA) and pay little attention to eicosapentaenoic acid (EPA).

Methods and results

We investigate the effect of EPA‐enriched phospholipids on cognitive deficiency in senescence‐accelerated prone 8 (SAMP8) mouse. Ten‐month‐old SAMP8 mice are fed with 2% (w/w) EPA‐enriched phosphatidylcholine/phosphatidyl ethanolamine (EPA‐PC/PE; EPA:DHA = 46.8:3.01) or 2% EPA‐enriched phosphatidylserine (EPA‐PS; biosynthesized from EPA‐PC/PE) for 8 weeks; we then test the behavioral performances in the Barnes maze test and Morris maze test; the changes of oxidative stress, apoptosis, neurotrophic factors, tau phosphorylation, and Aβ pathology are also measured. The results of behavior tests indicate that both EPA‐PC/PE and EPA‐PS significantly improve memory and cognitive deficiency. It is found that remarkable amelioration of oxidative stress and apoptosis occurs in both EPA‐PC/PE and EPA‐PS groups. EPA‐PS shows more ameliorative effects than EPA‐PC/PE on neurotrophic activity by decreasing hyper‐phosphorylation of tau and depressing the generation and accumulation of β‐amyloid peptide (Aβ).

Conclusion

These data suggest that EPA‐PS exhibits better effects than EPA‐PC/PE on ameliorating memory and cognitive function, which might be attributed to the phospholipid polar groups.
TALEN‐mediated gene targeting in porcine spermatogonia
Authors: Tang Lin , Bondareva Alla , González Raquel , Rodriguez‐Sosa Jose R. , Carlson Daniel F. , Webster Dennis , Fahrenkrug Scott , Dobrinski Ina
Published: February 2018

Spermatogonia represent a diploid germ cell population that includes spermatogonial stem cells. In this report, we describe new methods for isolation of highly enriched porcine spermatogonia based on light scatter properties, and for targeted mutagenesis in porcine spermatogonia using nucleofection and TALENs. We optimized a nucleofection protocol to deliver TALENs specifically targeting the DMD locus in porcine spermatogonia. We also validated specific sorting of porcine spermatogonia based on light scatter properties. We were able to obtain a highly enriched germ cell population with over 90% of cells being UCH‐L1 positive undifferentiated spermatogonia. After gene targeting in porcine spermatogonia, indel (insertion or deletion) mutations as a result of non‐homologous end joining (NHEJ) were detected in up to 18% of transfected cells. Our report demonstrates for the first time an approach to obtain a live cell population highly enriched in undifferentiated spermatogonia from immature porcine testes, and that gene targeting can be achieved in porcine spermatogonia which will enable germ line modification.
Hyperglycemia‐induced mouse trophoblast spreading is mediated by reactive oxygen species
Authors: Sánchez‐Santos Alejandra , Martínez‐Hernández María G. , Contreras‐Ramos Alejandra , Ortega‐Camarillo Clara , Baiza‐Gutman Luis A.
Published: February 2018

During embryo implantation, the outer layer of the blastocyst interacts with the endometrium giving rise to the development of the trophoblast cell lineage. The cells in this lineage participate in the penetration of endometrium due to their motility and invasive properties. The mechanisms that regulate the differentiation and invasive ability of these cells are essential for the establishment and maintenance of an efficient exchange between maternal and fetal tissues during pregnancy. In this context, hyperglycemia can induce oxidative stress causing alterations in the placenta. This study evaluated the role of reactive oxygen species (ROS) in the actions of high glucose concentration (HG) on trophoblast spreading and the expression of extracellular proteases in cultured mouse conceptuses. Blastocysts from gestational day 4 (GD4) were cultured until GD7 in HAM‐F10 medium and further treated for 48 hr with HG (25 mM glucose) from GD7 to GD9. This treatment induced larger trophoblast outgrowths and increased ROS concentration, which was associated with increased expression levels of urokinase‐type plasminogen activator (PLAU), plasminogen activator inhibitor 1 (PAI‐1), and matrix metalloproteinase 9 (MMP‐9). These effects were prevented by treatment with the non‐specific antioxidant N‐acetylcysteine (NAC) or apocynin, an inhibitor of NADPH oxidase. Our data suggest that the HG‐induced trophoblast spreading and the expression of PLAU, PAI‐1, and MMP‐9 were mediated by the production of ROS via NADPH oxidase activity. Our results shed light on placental alterations in gestational diabetes mellitus.
Activated receptor tyrosine kinases in granulosa cells of ovulating follicles in mice
Authors: Schuermann Yasmin , Siddappa Dayananda , Pansera Melissa , Duggavathi Raj
Published: February 2018

Successful ovulation requires the actions of gonadotropins along with those mediated by growth factors binding to their receptor tyrosine kinases (RTKs). There are several growth factors such as epidermal growth factor family ligands and interleukins that play a role during ovulation initiated by the preovulatory surge of luteinizing hormone (LH). The aim of this project was to analyze growth factor signaling pathways induced by LH in mouse granulosa cells. Immature female mice were treated with equine chorionic gonadotropin (eCG) followed 48 hr later by human chorionic gonadotropin (hCG) to induce follicular growth and ovulation. We performed protein array analysis where we identified higher phosphorylation of insulin‐like growth factor 1 receptor (IGF1R), the fibroblast growth factor receptor 2 (FGFR2) and ephrin receptor B1 (EPHB1) in granulosa cells at 4 hr post‐hCG compared to 0 hr hCG (p < 0.05). We report both a significant increase in transcript abundance (p < 0.05) and the phosphorylation level (p < 0.05) of the IGF1R in granulosa cells at hCG4h. The mRNA abundance of the Fgfr2 and Ephb1 receptors remained unaltered upon hCG treatment. Nonetheless, transcript abundance of the fibroblast growth factor 2 (Fgf2) ligand was elevated at hCG4h (p < 0.01). Based on these results we conclude that the preovulatory LH surge activates signaling pathways of IGF1R through increase in the expression of the Igf1r gene in granulosa cells of ovulating follicles in mice. The LH surge also appears to activate FGFR2 IIIc and EPHB1 signaling, although further investigation is required.
Pulsed gradient stimulated echo (PGStE) NMR shows spatial dependence of fluid diffusion in human stage IV osteoarthritic cartilage
Authors: Mailhiot Sarah E. , Codd Sarah L. , Brown Jennifer R. , Seymour Joseph D. , June Ronald K.
Published: February 2018

Purpose

Human osteoarthritic (OA) articular cartilage was investigated with spatially resolved pulsed gradient stimulated echo (PGStE) NMR using strong gradients. In this study, the diffusivity of fluid and biopolymer was characterized as a function of depth within human OA cartilage cores.

Methods

One dimensional (1D) spatially resolved diffusion profiles were measured for human OA cartilage using a standard pulsed gradient stimulated echo (PGStE) sequence with the addition of a read imaging gradient. Low gradient values (0.05 to 1.5 Tm−1) were used to measure fluid motion and high gradients (2.50 to 17.81 Tm−1) enabled analysis of biopolymer motion. Structural damage to cartilage was simulated using either salt or collagenase.

Results

These data demonstrate that fluid diffusion is sensitive to salt treatment and collagenase digestion, while biopolymer diffusion is sensitive only to collagenase digestion. Biopolymer and fluid diffusion are donor specific for human OA cartilage samples.

Conclusion

These data support that fluid diffusion is sensitive to the structure of cartilage while biopolymer diffusion is sensitive to the molecular weight of the biopolymers. The results show that diffusion of fluid and biopolymers in articular cartilage are sensitive to OA and provide complimentary information. Magn Reson Med 80:1170–1177, 2018. © 2018 International Society for Magnetic Resonance in Medicine.
A systematic review of urinary bladder hypertrophy in experimental diabetes: Part I. Streptozotocin‐induced rat models
Authors: Arioglu Inan Ebru , Ellenbroek Johanne H. , Michel Martin C.
Published: February 2018

Aims

To better understand the genesis and consequences of urinary bladder hypertrophy in animal models of diabetes. This part of a three‐article series will analyze urinary bladder hypertrophy in the diabetes mellitus type 1 model of rats injected with streptozotocin (STZ).

Methods

A systematic search for the key word combination “diabetes,” “bladder” and “hypertrophy” was performed in PubMed; additional references were identified from reference lists of those publications. All papers were systematically extracted for relevant information.

Results

A total of 39 studies were identified that quantitatively reported on bladder hypertrophy in rats upon injection of STZ; of which several reported on multiple time points yielding a total of 83 group comparisons. Bladder hypertrophy was found consistently, being fully developed as early as 1 week after STZ injection (bladder weight 188 ± 59% of matched control). Hypertrophy was similar across sexes and STZ doses (35‐40 vs 50‐65 mg/kg) but appeared greater with Wistar rats than other rat strains. The extent of bladder hypertrophy was not correlated to blood glucose concentrations, but normalization of blood glucose concentration by insulin treatment starting early after STZ injection prevented hypertrophy; insulin treatment starting after hypertrophy had established largely reversed it.

Conclusions

Bladder size approximately doubles after STZ injection in rats; the extent of hypertrophy is not linked to the severity of hyperglycemia but largely reversible by restoration of euglycemia.
Value of urodynamic findings in predicting upper urinary tract damage in neuro‐urological patients: A systematic review
Authors: Musco Stefania , Padilla‐Fernández Barbara , Del Popolo Giulio , Bonifazi Matteo , Blok Bertil F. M. , Groen Jan , ‘t Hoen Lisette , Pannek Jürgen , Bonzon Jerome , Kessler Thomas M. , Schneider Marc P. , Gross Tobias , Karsenty Gilles , Phé Véronique , Hamid Rizwan , Ecclestone Hazel , Castro‐Diaz David
Published: February 2018

Aim

The main goals of neurogenic lower urinary tract dysfunction (NLUTD) management are preventing upper urinary tract damage (UUTD), improving continence, and quality of life. Here, we aimed to systematically assess all available evidence on urodynamics predicting UUTD in patients with NLUTD.

Methods

A systematic review according to the Preferred Reporting Items for Systematic Reviews and Meta‐Analyses (PRISMA) Statement was performed in March 2017. Only neuro‐urological patients assessed by urodynamics were included. Any outcome of upper urinary tract function were evaluated.

Results

Forty‐nine studies (1 randomized controlled trial, 9 prospective, and 39 retrospective case series) reported urodynamic data on 4930 neuro‐urological patients. Of those, 2828 (98%) were spina bifida (SB) children. The total number of adults was 2044, mainly having spinal cord injury (SCI) (60%). A low bladder compliance was found in 568 (46.3%) and 341 (29.3%) of the paediatric and adult population, respectively. Hydronephrosis (HDN) was detected in 557 children (27.8%) in 19/28 studies and 178 adults (14.6%), mainly SCI, in 14/21 studies. Nine out of 30 multiple sclerosis (MS) patients affected by HDN (16.8%) showed low compliance in 4/14 studies.

Conclusions

Patients with SB and SCI have a higher risk of developing UUTD (mainly reported as HDN) compared to those with MS. Reduced compliance and high DLPP were major risk factors for UUTD. Although our findings clarify the mandatory role of urodynamics in the management of NLUTD, standardization and better implementation of assessments in daily practice may further improve outcomes of neuro‐urological patients based on objective measurements, that is, urodynamics.
Comparison of metabolic adaptations between endurance‐ and sprint‐trained athletes after an exhaustive exercise in two different calf muscles using a multi‐slice 31P‐MR spectroscopic sequence
Authors: Moll Kevin , Gussew Alexander , Nisser Maria , Derlien Steffen , Krämer Martin , Reichenbach Jürgen R.
Published: February 2018

Measurements of exercise‐induced metabolic changes, such as oxygen consumption, carbon dioxide exhalation or lactate concentration, are important indicators for assessing the current performance level of athletes in training science. With exercise‐limiting metabolic processes occurring in loaded muscles, 31P‐MRS represents a particularly powerful modality to identify and analyze corresponding training‐induced alterations. Against this background, the current study aimed to analyze metabolic adaptations after an exhaustive exercise in two calf muscles (m. soleus – SOL – and m. gastrocnemius medialis – GM) of sprinters and endurance athletes by using localized dynamic 31P‐MRS. In addition, the respiratory parameters VO2 and VCO2, as well as blood lactate concentrations, were monitored simultaneously to assess the effects of local metabolic adjustments in the loaded muscles on global physiological parameters. Besides noting obvious differences between the SOL and the GM muscles, we were also able to identify distinct physiological strategies in dealing with the exhaustive exercise by recruiting two athlete groups with opposing metabolic profiles. Endurance athletes tended to use the aerobic pathway in the metabolism of glucose, whereas sprinters produced a significantly higher peak concentration of lactate. These global findings go along with locally measured differences, especially in the main performer GM, with sprinters revealing a higher degree of acidification at the end of exercise (pH 6.29 ± 0.20 vs. 6.57 ± 0.21). Endurance athletes were able to partially recover their PCr stores during the exhaustive exercise and seemed to distribute their metabolic activity more consistently over both investigated muscles. In contrast, sprinters mainly stressed Type II muscle fibers, which corresponds more to their training orientation preferring the glycolytic energy supply pathway. In conclusion, we were able to analyze the relation between specific local metabolic processes in loaded muscles and typical global adaptation parameters, conventionally used to monitor the training status of athletes, in two cohorts with different sports orientations.
Impact of Gastrostomy Feeding Tube Placement on the 1‐Year Trajectory of Care in Patients After Stroke
Authors: Wilmskoetter Janina , Simpson Annie N. , Logan Sarah L. , Simpson Kit N. , Bonilha Heather S.
Published: February 2018

Background

Percutaneous endoscopic gastrostomy (PEG) feeding tubes are commonly placed in acute stroke patients with a need for enteral nutrition. However, PEG tubes are associated with medical complications and a decrease in quality of life. We compared the 1‐year care trajectory of stroke patients with and without PEG tube placement to enhance knowledge about the long‐term impact of PEG tube placement.

Methods

We conducted a retrospective analysis of commercially insured stroke patients included in the Truven Health MarketScan Research Databases of 2011. We analyzed their index hospital stay and conducted 1‐month, 3‐months, 6‐months, and 1‐year follow‐ups. We compared admissions to inpatient rehabilitation facilities, acute hospitals, skilled nursing facilities, outpatient hospital visits, and home visits for stroke patients with and without PEG tube placement using unadjusted and adjusted modelling.

Results

Of the 8911 included stroke patients, 148 patients (1.7%) had a PEG tube placed during their index hospital stay. After controlling for age, gender, stroke severity, comorbidities, and stroke type, PEG tube placement was an independent predictor for admissions to inpatient rehabilitation facilities and skilled nursing facilities. Furthermore, PEG tube placement was an independent predictor for all‐cause, unplanned hospital readmissions in a multivariable logistic model (area under the receiver operating characteristic curve was .84).

Conclusion

Stroke patients who receive a PEG tube can expect a significantly different care trajectory after being discharged from the acute hospital. Our findings can aide in predicting recovery and planning resources and identifying gaps and points for improvement in stroke care for patients with PEG tube placement.
A higher‐order equilibrium finite element method
Authors: Olesen K. , Gervang B. , Reddy J. N. , Gerritsma M.
Published: February 2018

In this paper, a mixed spectral element formulation is presented for planar, linear elasticity. The degrees of freedom for the stress are integrated traction components, ie, surface force components. As a result, the tractions between elements are continuous. The formulation is based on minimization of the complementary energy subject to the constraints that the stress field should satisfy equilibrium of forces and moments. The Lagrange multiplier, which enforces equilibrium of forces, is the displacement field and the Lagrange multiplier, which enforces equilibrium of moments, is the rotation. The formulation satisfies equilibrium of forces pointwise if the body forces are piecewise polynomial. Equilibrium of moments is weakly satisfied. Results of the method are given on orthogonal and curvilinear domains, and an example with a point singularity is given.
Improved eigenfrequencies of mechanical systems by combining complementary models
Authors: Moitinho de Almeida J. P. , Maunder E. A. W.
Published: February 2018

In this paper, we propose a novel approach to combine two complementary numerical models of the dynamical behaviour of mechanical systems: primal (compatible) and dual (equilibrated). This combined model provides an improved estimate of the eigenfrequencies of the system by feeding each model with information from the other. Numerical solutions obtained from both the fundamental models and from the proposed approach are presented and studied. This approach will be applicable to any eigenvalue problem associated with a PDE that can be expressed by complementary numerical models.
Simultaneously reinforce and toughen polypropylene by in‐situ introducing polylactic acid microfibrils
Authors: Su Juan‐juan , Meng Yang , Zhu Fan , Han Jian , Wang Ke , Fu Qiang
Published: February 2018

A petroleum‐based polymer, isotactic polypropylene (iPP), and a biodegradable polymer, poly(lactic acid) (PLA), were compounded and molded into parts through the micro‐injection technique. A systematic structural investigation indicated that the microfibrillation of PLA minor phase depended on the operation parameter of inter‐mixer, ie, rotor speed. The higher rotor speed, the lower viscosity ratio of the PLA/iPP pair was favorable for microfibrillation occurred during micro‐injection process. The PLA microfibrils with high aspect ratio was successfully introduced into iPP matrix, and the tensile strength and strain at break of iPP/PLA blends were simultaneously improved. This study suggests a promising method for designing special microfibrillar morphology in polymer blend by using conventional melt processing techniques.
Friction and wear behavior of PI and PTFE composites for ultrasonic motors
Authors: Zhao Gai , Wu Chuhan , Zhang Liangchi , Song Jingfu , Ding Qingjun
Published: February 2018

High‐performance polymer‐based frictional materials have become increasingly important to improve the mechanical output properties of ultrasonic motors. This study discussed the friction and wear behavior of 2 dominating frictional materials of polymer composites for ultrasonic motors, polyimide (PI), and polytetrafluoroethylene (PTFE) filled by aramid fibers (AF) and molybdenum disulfide (MoS2). To explore the wear mechanisms, the tribo‐pair contact stress was theoretically characterized, and the interface temperature rise was numerically predicted. The predictions showed that the flash temperature on asperity tips could reach the glass transition temperature of the polymer materials. The experimental results indicated that the contact stress and sliding speed have a small effect on the friction of the PI composite but influence considerably the friction of the PTFE composite. A higher contact stress brings about a higher specific wear rate, but a higher sliding speed reduces the wear rate. Compared with AF/MoS2/PTFE, the AF/MoS2/PI has much better tribological performance under high loads and speeds.
Reinforcement of epoxidized natural rubber through the addition of sepiolite
Authors: Hayeemasae Nabil , Ismail Hanafi
Published: February 2018

Sepiolite reinforced epoxidized natural rubber (ENR) composites were prepared by incorporation different loadings of sepiolite. Curing characteristics, mechanical properties, morphology and thermal stability of sepiolite‐filled ENR composites were studied. Adding sepiolite into ENR has resulted in remarkable improvement of curing characteristics, mechanical properties and thermal stability. This is attributed to the unique structure of sepiolite itself. It gives a greater interaction between hydroxyl and/or siloxane groups of sepiolite and epoxide segment of ENR. The mechanical properties are very good agreement to the SEM micrographs where more surface roughness is observed upon the addition of sepiolite. Further evidence was found for the thermal decomposition temperature of the composites. The obtained thermogravimetric profiles indicate that their thermal stability was clearly enhanced irrespective of sepiolite loadings. POLYM. COMPOS., 40:924–931, 2019. © 2018 Society of Plastics Engineers
Simultaneous separation and determination of praeruptorin A, B and C by micellar electrokinetic chromatography using sodium dodecyl sulphate and sodium cholate as mixed micelles
Authors: Chen Meng , Chang Ruimiao , Xu Liying , Huang Yayun , Zhang Hongfen , Chen Anjia
Published: February 2018

Introduction

Praeruptorin A, B and C are major bioactive constituents in Peucedani Radix. They display anti‐inflammatory effect, anti‐hypertension effect, antiplatelet aggregation, potential anti‐cancer activities and so on. They are worthy of investigation as potentially novel and versatile drugs.

Objective

To develop a method using micellar electrokinetic chromatography (MEKC) for the application in simultaneously separation and determination of praeruptorin A, B and C from Peucedani Radix and its medicinal preparations.

Methods

Method optimisation was carried out by investigating influences of significant factors on the separation. The method was subjected to validation. The determination of praeruptorin A, B and C in Peucedani Radix and its drug formulations was accomplished by the developed method.

Results

The optimal separation condition was 20 mM borate buffer containing 40 mM sodium cholate (SC), 22 mM sodium dodecyl sulphate (SDS) and 25% (v/v) acetonitrile (pH 10.00); 15 kV of voltage; 25°C of temperature; detection at 224 nm. Under this condition, three analytes were baseline separated within 16 min. A good linearity was obtained with correlation coefficients from 0.9988 to 0.9995. The limits of detection (LODs) and limits of quantitation (LOQs) ranged from 0.50 to 0.80 μg/mL and from 1.50 to 2.50 μg/mL, respectively. The recoveries ranged between 95.3% and 103.4%.

Conclusion

The proposed method has been successfully applied to the simultaneous determination of praeruptorin A, B and C in Peucedani Radix and its pharmaceutical preparations. Additionally, it could be a potential alternative to the quality control of Peucedani Radix.
Do FDA label changes work? Assessment of the 2010 class label change for proton pump inhibitors using the Sentinel System's analytic tools
Authors: Sobel Rachel E. , Bate Andrew , Marshall James , Haynes Kevin , Selvam Nandini , Nair Vinit , Daniel Gregory , Brown Jeffrey S. , Reynolds Robert F.
Published: February 2018

Purpose

To pilot use of the US Food and Drug Administration's (FDA's) Sentinel System data and analytic tools by a non‐FDA stakeholder through the Innovation in Medical Evidence Development and Surveillance system of the Reagan Udall Foundation. We evaluated the US FDA 2010 proton pump inhibitor (PPI) class label change that warned of increased risk of bone fracture, to use PPIs for the lowest dose and shortest duration, and to manage bone status for those at risk for osteoporosis.

Methods

The cohort consisted of adults aged 18 years or older prescribed PPIs without fracture risk factors. We evaluated incident and prevalent uses of the 8 PPIs noted in the label change. Outcomes evaluated before and after label change were PPI dispensing patterns, incident fractures, and osteoporosis screening or interventions. Consistent with FDA use of descriptive tools, we did not include direct comparisons or statistical testing.

Results

There were 1 488 869 and 2 224 420 incident PPI users in the before [PRE] and after [POST] periods, respectively. Users with 1 year or more of exposure decreased (8.4% vs 7.5%), as did mean days supplied/user (130.4 to 113.7 d among all users and 830.8 to 645.4 d among users with 1 y or more of exposure). Osteoporosis screening and interventions did not appear to increase, but the proportion of patients with fractures decreased (4.4% vs 3.1%). Prevalent user results were similar.

Conclusions

This analysis demonstrated the ability to use Sentinel tools to assess the effectiveness of a label change and accompanying communication at the population level and suggests an influence on subsequent dispensing behavior.
Disclosing the crystallization behavior and morphology of poly(ϵ‐caprolactone) within poly(ϵ‐caprolactone)/poly(l‐lactide) blends
Authors: Han Weiqiang , Liao Xia , He Bin , Yang Qi , Li Guangxian
Published: February 2018

In this work, the effect of poly(l‐lactide) (PLLA) components on the crystallization behavior and morphology of poly(ϵ‐caprolactone) (PCL) within PCL/PLLA blends was investigated by polarized optical microscopy, DSC, SEM and AFM. Morphological results reveal that PCL forms banded spherulites in PCL/PLLA blends because the interaction between the two polymer components facilitates twisting of the PCL lamellae. Additionally, the average band spacing of PCL spherulites monotonically decreases with increasing PLLA content. With regard to the crystallization behaviors of PCL, the crystallization ability of PCL is depressed with increase of the PLLA content. However, it is interesting to observe that the growth rate of PCL spherulites is almost independent of the PLLA content while the overall isothermal crystallization rate of PCL within PCL/PLLA blends decreases first and then increases at a given crystallization temperature, indicating that the addition of PLLA components shows a weak effect on the growth rate of the PCL but mainly on the generation of nuclei. © 2018 Society of Chemical Industry
Blocked crystallization in capped ultrathin polymer films studied by molecular simulations
Authors: Qiu Xiaoyan , Zhang Yongqiang , Wu Haitao , Yang Rui , Yang Jun , Liu Rongjuan , Liu Yong , Zhou Zhiping , Hao Tongfan , Nie Yijing
Published: February 2018

The crystallization of capped ultrathin polymer films is closely dependent on film thickness and interfacial interaction. Using dynamic Monte Carlo simulations, the crystallization behaviors of polymer films confined between two substrates were investigated. The crystallization rate of confined polymers is reduced with high interfacial interactions. Above a critical strength of interfacial interaction, polymer crystallization in the thin film is inhibited within the simulation time scales. An increase in film thickness leads to a rise in critical interfacial interaction. In thicker films, the chains have more space to change conformation to form crystal stems. In addition, there are fewer absorbed segments in confined chains for the thicker films, and thus the chains have stronger ability to adjust their conformation. Therefore an increase in film thickness can cause a reduction in the entropic barrier required for the formation of crystals and thus an increase in the critical interfacial interaction. © 2018 Society of Chemical Industry
Complications and risk factors in pediatric bronchoscopy in a tertiary pediatric respiratory center
Authors: Carlens Julia , Fuge Jan , Price Timothy , DeLuca David S. , Price Mareike , Hansen Gesine , Schwerk Nicolaus
Published: February 2018

Bronchoscopy is an established procedure routinely used by pediatric pulmonologists. Despite its frequent application, data on complications and specific risk factors are scarce and sometimes conflicting.

Aim

The aim of this study was to evaluate frequency and severity of clearly defined complications of bronchoscopy in children that occur both during and after the procedure, and to identify potential risk factors.

Method

A retrospective single‐center analysis of 670 elective bronchoscopies in 522 children aged 0‐17 years during the time period of 2008‐2012 was performed. Procedures in intensive care unit patients and children after lung transplantation were excluded.

Results

Mean patient age was 5.58 years, 61.5% had underlying chronic diseases. Intraprocedural complications occurred in 7.2% of all procedures; of these, hypoxemia was the most common, occuring in 4.8% of cases. Postprocedural adverse events were documented in 25.8%, the most frequent of which were fever in 14.2% and transient oxygen dependency in 13.4% of cases. No bronchoscopy related deaths occurred. Multivariate logistic regression was used to identify risk factors for (1) any complication, or (2) severe complications. Age below two years (OR 1.837 [1.224‐2.757], P = 0.003) and primary ciliary dyskinesia (OR 4.821 [2.018‐11.552], P < 0.001) significantly contributed to risk of any complication. Age below 2 years (OR 2.478 [1.072‐5.728], P = 0.034) and underlying cardiovascular disease (OR 2.678 [1.013‐7.077], P = 0.047) were independent risk factors for severe complications.

Conclusion

Bronchoscopy in children is relatively safe. Nevertheless, adverse events can occur and knowledge of risk factors may help prevent complications.
Genome‐wide and expression‐profiling analyses suggest the main cytochrome P450 genes related to pyrethroid resistance in the malaria vector, Anopheles sinensis (Diptera Culicidae)
Authors: Yan Zheng‐Wen , He Zheng‐Bo , Yan Zhen‐Tian , Si Feng‐Ling , Zhou Yong , Chen Bin
Published: February 2018

BACKGROUND

Anopheles sinensis is one of the major malaria vectors. However, pyrethroid resistance in An. sinensis is threatening malaria control. Cytochrome P450‐mediated detoxification is an important pyrethroid resistance mechanism that has been unexplored in An. sinensis. In this study, we performed a comprehensive analysis of the An. sinensis P450 gene superfamily with special attention to their role in pyrethroid resistance using bioinformatics and molecular approaches.

RESULTS

Our data revealed the presence of 112 individual P450 genes in An. sinensis, which were classified into four major clans (mitochondrial, CYP2, CYP3 and CYP4), 18 families and 50 subfamilies. Sixty‐seven genes formed nine gene clusters, and genes within the same cluster and the same gene family had a similar gene structure. Phylogenetic analysis showed that most of An. sinensis P450s (82/112) had very close 1: 1 orthology with Anopheles gambiae P450s. Five genes (AsCYP6Z2, AsCYP6P3v1, AsCYP6P3v2, AsCYP9J5 and AsCYP306A1) were significantly upregulated in three pyrethroid‐resistant populations in both RNA‐seq and RT‐qPCR analyses, suggesting that they could be the most important P450 genes involved in pyrethroid resistance in An. sinensis.

CONCLUSION

Our study provides insight on the diversity of An. sinensis P450 superfamily and basis for further elucidating pyrethroid resistance mechanism in this mosquito species. © 2018 Society of Chemical Industry.
Preparation and characterization of polypropylene/sodium propionate (PP/SP) composite films for bread packaging application
Authors: Thanakkasaranee Sarinthip , Kim Dowan , Seo Jongchul
Published: February 2018

To prolong the shelf life of bread, polypropylene/sodium propionate (PP/SP) composite films were prepared via a melt‐extrusion process. To investigate the feasibility of using PP/SP composite films as a bread packaging material, their chemical structure, morphology, mechanical properties, barrier properties against water, surface properties, and antimicrobial properties were investigated. A storage test for bread was also conducted. The mechanical and thermal stability of the PP/SP composite films enhanced with increasing SP content. Compared with pure PP, the PP/SP composites had increased hydrophilicity that increased with increasing SP content. These composite films showed enhanced antimicrobial activity against both Gram‐negative and Gram‐positive microorganisms. This was due to the interaction of SP and water originating from the bread, which modifies the pH of the bread and causes destruction of the cellular structures of fungi and also reduces the growth rate of bacteria. The enhanced thermal, mechanical, antifungal, and antimicrobial properties achieved by the addition of SP can be beneficial for maintaining the freshness of bread and prolonging its shelf life.
Decidualization of the human endometrium
Authors: Okada Hidetaka , Tsuzuki Tomoko , Murata Hiromi
Published: February 2018

Background

Decidualization of the human endometrium, which involves a dramatic morphological and functional differentiation of human endometrial stromal cells (ESCs), is essential for the establishment of a successful pregnancy. Decidualization results from a complex interplay of transcription factors, morphogens, cytokines, cell cycle regulators, and signaling pathways.

Methods

Based on a literature review, the regulation of, and the molecular mechanisms involved in, the decidualization of the endometrium are described.

Main findings

Progesterone, together with proteins that are regulated by progesterone and/or cyclic adenosine monophosphate, including homeobox A10, forkhead box O1, signal transducers and activators of transcription, and heart and neural crest derivatives expressed transcript 2, forms a critical network for ESC decidualization and is a prerequisite to successful implantation. Decidualized ESCs contribute to the microenvironment at the feto–maternal interface and its direct or indirect influence on extracellular matrix remodeling, regulation of the local immune response, anti‐oxidative stress, and angiogenesis (vascular maturation). Impairment of this process is associated with a variety of pregnancy disorders, including infertility, recurrent miscarriages, and uteroplacental disorders.

Conclusion

A deeper understanding of the process of decidualization is expected to provide new insights into the fields of reproductive biology and reproductive medicine.
Output feedback stabilization for a general class of nonlinear systems via sampled‐data control
Authors: Li Zhanjie , Zhao Jun
Published: February 2018

This paper considers global output feedback stabilization via sampled‐data control for a general class of nonlinear systems, which admit unknown control coefficients and nonderivable output function. A sector region of the output function is given by utilizing a technical lemma, and a sampled‐data controller is designed by combining a robust state stabilizer and a reduced‐order sampled‐data observer. By carefully choosing an appropriate sampling period, the proposed controller guarantees the globally asymptotical stability of the closed‐loop systems.
Stochastic domination in space‐time for the contact process
Authors: van den Berg Jacob , Bethuelsen Stein Andreas
Published: February 2018

Liggett and Steif (2006) proved that, for the supercritical contact process on certain graphs, the upper invariant measure stochastically dominates an i.i.d. Bernoulli product measure. In particular, they proved this for and (for infection rate sufficiently large) d‐ary homogeneous trees Td. In this paper, we prove some space‐time versions of their results. We do this by combining their methods with specific properties of the contact process and general correlation inequalities. One of our main results concerns the contact process on Td with . We show that, for large infection rate, there exists a subset Δ of the vertices of Td, containing a “positive fraction” of all the vertices of Td, such that the following holds: The contact process on Td observed on Δ stochastically dominates an independent spin‐flip process. (This is known to be false for the contact process on graphs having subexponential growth.) We further prove that the supercritical contact process on observed on certain d‐dimensional space‐time slabs stochastically dominates an i.i.d. Bernoulli product measure, from which we conclude strong mixing properties important in the study of certain random walks in random environment.
Theoretical and experimental analyses of the deposited silver thin films
Authors: Haji Abdolvahab Rouhollah , Zamani Meymian Mohammad Reza
Published: February 2018

The silver thin films have been prepared using magnetron DC‐sputtering. We discuss in detail the thin films AFM images and their properties in different sputtering times of 2 to 6 minutes. Despite the low thickness of the films, the roughness saturation amounts, Ws, are well separated. The surface data do not follow the normal Family‐Vicsek scaling, and we have the local growth exponent, β(Ws(t)∼tβ). We obtained the global roughness scaling exponent α=0.36 and growth exponent, β=0.50.

We also obtain the fractal spectrum of the data, f(α). The results show that the spectrum is right‐hook like. It distinguishes between different film thicknesses even in small sizes of hundreds of nanometers. Furthermore, we measure the surface conductivities and compare them to the thin film roughnesses. We investigate the roughness and fractality of the AFM data, looking for their relations to width and conductivity of the silver thin film samples.
Structure, corrosion, and tribological properties of CrSiN coatings with various Si contents in 3.5% NaCl solution
Authors: Wang Haixin , Ye Yuwei , Wang Yongxin
Published: February 2018

The CrSiN coatings with different silicon contents were deposited on 304L stainless steel and single silicon substrates using medium frequency magnetron sputtering via adjusting the silicon target current. Microstructures, mechanical, corrosion, and tribological performances were systematically investigated by the corresponding equipment. The results showed that the CrSiN coatings were composed of 2 phases: the nanocrystalline CrN coordinated with adjacent Si3N4 to form a typical nanocrystalline amorphous structure. With the increase of silicon content, the hardness emerged a rising trend until 12.65 at.%, where the hardness reached its highest value at approximately 22 GPa. At the moment, the friction coefficient and wear rate were approximately 0.27 and 6.9 × 10−8 mm3/Nm, respectively, which were 18.75% and 61.67% lower than that of the CrN coating, respectively. This mainly attributed to the lubrication of tribochemical products of SiO2 and Si(OH)4. In addition, excellent toughness, high hardness, preferable adhesion, and good corrosion resistance also contributed to improve the tribological properties of CrSiN coating.
Efficient and Eco‐Friendly One‐Pot Synthesis of Functionalized Furan‐2‐one, Pyrrol‐2‐one, and Tetrahydropyridine Using Lemon Juice as a Biodegradable Catalyst
Authors: Khan M. Musawwer , Khan Sarfaraz , Saigal  , Sahoo Subash C.
Published: February 2018

New and facile one‐pot approach for the syntheses of polysubstituted pyrrol‐2‐one, furan‐2‐one and tetrahydropyridines (THPDs) from easily available starting materials using lemon juice as a green catalyst is presented. The synthesis of diverse furan‐2‐one and pyrrol‐2‐one derivatives were achieved from dialkyl acetylenedicarboxylates, different amines and aldehydes in high yields and short reaction times by employing 0.25 mL of lemon juice at 110 oC under solvent‐free condition. THPDs, on the other hand, were synthesized via the reaction among β‐ketoesters, various aromatic aldehydes, and amines in the presence of 0.25 mL of lemon juice in ethanol at room temperature. The molecular structure of compound pyrrol‐2‐one 7e and THPD 10g were confirmed by the single crystal X‐ray analysis. Application of cheap and green catalyst, environmentally benign reaction condition, good to high yields, applicable to a broad range of substrates and no column chromatographic separation are some salient features of this protocol.
The Asymmetric Friedel‐Crafts Reaction of Indoles with Arylidenemalonates Catalyzed by MgI2/PyBox Complexes
Authors: Anokhin Maksim V. , Feofanov Mikhail N. , Averin Alexei D. , Beletskaya Irina P.
Published: February 2018

A mild and efficient catalytic enantioselective addition of indoles to dimethyl arylidenemalonates using MgI2 and PyBOX ligands bearing halogen substituents has been elaborated. The reactions were conducted in DCM at low temperature generally providing high yields (up to 99%), while enantioselectivity was shown to be strongly dependent on the nature of substituents in arylidenemalonate and indole reaching 83% ee. The reactivity of arylidenemalonates under described conditions was found to be enough different from that in copper‐catalyzed Friedel‐Crafts alkylation.
Syntheses, Characterization and Applications of Graft Copolymers of Sago Starch – A Review
Authors: Lele Vidyagauri V. , Kumari Savita , Niju Harshada
Published: February 2018

Modified natural polymers with improved structural, physical, and chemical properties have been gaining increasing importance in the industry as they are abundant, cheap, renewable, and biodegradable. Graft copolymerization is one of the effective ways to improve the properties of natural polymers. Sago starch (SG) based graft copolymers are becoming increasingly important due to their remarkable adhesion, high water absorbency, and biodegradability. There are many reports on the physico‐chemical characteristics, pharmaceutical applications, and several other chemical modifications (esterification, etherification, oxidation of OH groups etc.) of SG, but only a few review articles include studies on its graft copolymers. This review article summarizes use of different chemical initiators and irradiation techniques for generation of starch macroradicals. It also includes the effect of monomer and initiator concentration, reaction time, and temperature on grafting parameters such as percentage grafting and grafting efficiency. It discusses the employment of techniques such as Infra‐red spectroscopy, Scanning Electron Microscopy, Thermogravimetric analysis, Differential Scanning Calorimetry, and X‐ray diffraction in the characterization of graft copolymers of SG. Owing to excellent mechanical and swelling properties, graft copolymers of SG find application in various fields such as chelating resins, drug delivery systems, wound dressing, coagulants, paper additives, film coatings etc.
The Modifications in Physicochemical and Functional Properties of Proso Millet Starch after Ultra‐High Pressure (UHP) Process
Authors: Li Wenhao , Gao Jiaxing , Saleh Ahmed S. M. , Tian Xiaolin , Wang Peng , Jiang Hao , Zhang Guoquan
Published: February 2018

Proso millet starch suspensions (30%, W/V) are subjected to UHP treatment at 150, 300, 450, and 600 MPa for 15 min in order to produce a modified starch for food applications. Besides, the UHP‐gelatinized starch gels are stored at room temperature for 192 h and the recrystallization characteristics are investigated during the storage time. The gelatinization extent of starch is increased with the increase in pressure level and the starch is fully gelatinized at 600 MPa. The XRD patterns show that the UHP at 600 MPa converted the A‐type crystals to the B‐type. The DSC data reveal an increase in gelatinization temperatures and a decrease in gelatinization enthalpy after treatment at 150–450 MPa. Pasting property analysis shows that trough and final viscosity, pasting temperature and peak time are increased; however, peak and breakdown viscosity are decreased with the increase in pressure level up to 600 MPa. UHP treatment resulted in a higher swelling capacity and solubility at a relatively low temperature. XRD and DSC are also used to monitor retrogradation through the growth of diffraction peaks of the recrystallized starch and the increase in the melting enthalpy. The extent of retrogradation is plotted as a function of the storage time.
Climate and colonialism
Authors: Mahony Martin , Endfield Georgina
Published: February 2018

Recent years have seen a growth in scholarship on the intertwined histories of climate, science, and European imperialism. Scholarship has focused both on how the material realities of climate shaped colonial enterprises, and on how ideas about climate informed imperial ideologies. Historians have shown how European expansion was justified by its protagonists with theories of racial superiority, which were often closely tied to ideas of climatic determinism. Meanwhile, the colonial spaces established by European powers offered novel “laboratories” where ideas about acclimatization and climatic improvement could be tested on the ground. While historical scholarship has focused on how powerful ideas of climate informed imperial projects, emerging scholarship in environmental history, history of science, and historical geography focuses instead on the material and cognitive practices by which the climates of colonial spaces were made known and dealt with in fields such as forestry, agriculture, and human health. These heretofore rather disparate areas of historical research carry great contemporary relevance for studies of how climates and their changes have been understood, debated, and adapted to in the past.

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Climate, History, Society, Culture > Major Historical Eras