bluuebunny/crossref_metadata_2025 huggingface dataset:
Longitudinal Ultrasound Curriculum Incorporation at West Virginia University School of Medicine: A Description and Graduating Students' Perceptions
Authors: Minardi Joseph , Ressetar Holly , Foreman Theresa , Craig Kristen , Sharon Melinda , Bassler John , Davis Stephen , Machi Anthony , Cottrell Scott , Denne Nicolas , Ferrari Norman , Landreth Kenneth , Palmer Bruce , Schaefer Gregory , Tallaksen Robert , Wilks David , Williams Dorian
Published: May 2018

Objectives

Sonography is a clinical tool being incorporated in multiple medical specialties with evidence of improved patient care and cost. Some schools have begun implementing ultrasound curricula. We hope to build upon that foundation and provide another potential framework of incorporation. There are several barriers, including curricular space, equipment and physical space, adequate faculty, and performing assessment.

Methods

At West Virginia University, we began a longitudinal ultrasound curriculum in 2012 with incorporation of didactic and practical sessions into gross anatomy, our systems‐based second‐year curriculum, physical diagnosis course, and clinical rotations. We included both written and practical assessment from the onset. After the initial 4 years, the first graduates were surveyed on their perceptions of the curriculum. Responses were correlated with specialty choice and clinical campus site.

Results

Based on our survey (90% response rate), students felt sonography was useful for anatomical understanding and patient care. Overall, 93% of our respondents reviewed the curriculum favorably. Qualitative feedback was very positive, with students desiring more ultrasound education and more required components, specifically in clinical rotations.

Conclusions

Based on these results, some changes have already been implemented, including decreased student‐to‐instructor ratios, more open scan time, and more required components. The breadth of formal assessment has increased. Multiple pilot programs for clinical rotations are being developed. There is an ongoing need for faculty development and continued assessment of ultrasound competency.
Ultrasound‐Guided Posterior Antebrachial Cutaneous Nerve Block: Technical Description and Block Distribution in Healthy Volunteers
Authors: Finneran John J. , Sandhu NavParkash
Published: May 2018

The posterior antebrachial cutaneous nerve branches from the radial nerve proximal to the elbow and supplies sensation to the posterior aspect of the forearm. With a high‐frequency linear transducer, the posterior antebrachial cutaneous nerve was identified in 8 healthy volunteers. Under aseptic conditions and with an ultrasound‐guided in‐plane technique, 1% lidocaine was injected circumferentially around the nerve. In each participant, the block was successful, and neither incidental blocks of other nerves nor any other complications were observed. These results demonstrate that the posterior antebrachial cutaneous nerve can be blocked to provide anesthesia or analgesia to the posterior forearm.
Placental Location and the Development of Hypertensive Disorders of Pregnancy
Authors: Salama‐Bello Rosana , Duncan Jose R. , Howard Samantha L. , Song Jun , Schenone Mauro H.
Published: May 2018

Objectives

Abnormal placentation is an important factor in the pathogenesis of preeclampsia. As a result of diminished blood flow, the incidence of preeclampsia might be higher in patients with laterally located placentas compared to patients with centrally located placentas. The objective of this study was to evaluate the relationship between placental location and the development of hypertensive disorders of pregnancy.

Methods

Patients with singleton pregnancies who were seen in our ultrasound unit and delivered at our institution from October 2014 to April 2015 were included. The incidence of hypertensive disorders was compared in those with a lateral placental location and those with centrally located placentas (placental locations other than lateral). Baseline characteristics and pregnancy outcomes were compared between groups. The χ2 test, Fisher exact test, Mann‐Whitney U test, and t test were used when appropriate. P < .05 was considered significant.

Results

We included 464 patients; 411 (88.57%) had centrally located placentas, and 53 (11.42%) had laterally located placentas. The incidence of hypertensive disorders of pregnancy was similar between groups (21% versus 19%; P = .71). Gestational age at delivery (P = .73), and small for gestational age (P = .96) were also similar between our study groups.

Conclusions

In our study, there was no difference in the rate of hypertensive disorders of pregnancy between patients with central and laterally located placentas.
Previous Gestational Diabetes Increases Atherogenic Dyslipidemia in Subsequent Pregnancy and Postpartum
Authors: Prados Montserrat , Flores‐Le Roux Juana A. , Benaiges David , Llauradó Gemma , Chillarón Juan J. , Paya Antoni , Pedro‐Botet Juan
Published: May 2018

In a cohort of women with previous gestational diabetes mellitus (GDM), we aimed to ascertain whether women with abnormal glucose tolerance 1‐year postdelivery had a more atherogenic lipid profile during and after pregnancy than those with normal glucose tolerance. A prospective cohort study with longitudinal design between January 2004 and March 2016 was conducted. Three hundred and six (56.8%) of 537 women diagnosed with GDM during the studied period attended a control visit during the first year after delivery. Of these, 112 (36.6%) had prediabetes and 16 (5.2%) had type 2 diabetes mellitus. No significant differences during pregnancy were found in total, low‐density lipoprotein, high‐density lipoprotein (HDL) cholesterol, and triacylglycerol (TAG) concentrations among the three groups. Only HDL cholesterol and TAG levels differed significantly among groups at 2 and 12 months after delivery. Logistic regression analysis revealed pregnancy HDL and glucose metabolism status to be associated with the HDL cholesterol concentration 1‐year postdelivery. Furthermore, the only independent factor associated with TAG levels 1 year after delivery was the gestational TAG concentration. In summary, an overweight multiethnic group of women with prior GDM presented a high incidence of postpartum dysglycemia (41.8%). HDL‐cholesterol and TAG levels, both components of the metabolic syndrome, differed significantly among the three study groups in the glucose‐metabolism status at 2 and 12 months after delivery. Women with previous GDM must be followed up in the postpartum period for early detection and management of lipid and glucose disorders.
Parameters in fractional laser assisted delivery of topical anesthetics: Role of laser type and laser settings
Authors: Meesters Arne A. , Nieboer Marilin J. , Kezic Sanja , de Rie Menno A. , Wolkerstorfer Albert
Published: May 2018

Background and Objectives

Efficacy of topical anesthetics can be enhanced by pretreatment of the skin with ablative fractional lasers. However, little is known about the role of parameters such as laser modality and laser density settings in this technique. Aims of this study were to compare the efficacy of pretreatment with two different ablative fractional laser modalities, a CO2 laser and an Er:YAG laser, and to assess the role of laser density in ablative fractional laser assisted topical anesthesia.

Study Design/Materials and Methods

In each of 15 healthy subjects, four 10 × 10 mm test regions on the back were randomized to pretreatment (70–75 μm ablation depth) with CO2 laser at 5% density, CO2 laser at 15% density, Er:YAG laser at 5% density or Er:YAG laser at 15% density. Articaine hydrochloride 40 mg/ml + epinephrine 10 μg/ml solution was applied under occlusion to all four test regions. After 15 minutes, a pass with the CO2 laser (1,500 μm ablation depth) was administered as pain stimulus to each test region. A reference pain stimulus was given on unanesthetized skin. The main outcome parameter, pain, was scored on a 0–10 visual analogue scale (VAS) after each pain stimulus.

Results

Median VAS scores were 1.50 [CO2 5%], 0.50 [CO2 15%], 1.50 [Er:YAG 5%], 0.43 [Er:YAG 15%], and 4.50 [unanesthetized reference]. VAS scores for all pretreated test regions were significantly lower compared to the untreated reference region (P < 0.01). We found no significant difference in VAS scores between the CO2 and the Er:YAG laser pretreated regions. However, VAS scores were significantly lower at 15% density compared to 5% density for both for the CO2 laser (P < 0.05) and the Er:YAG laser (P < 0.01). Pretreatment with the CO2 laser was considered slightly more painful than pretreatment with Er:YAG laser by the subjects.

Conclusion

Fractional laser assisted topical anesthesia is effective even with very low energy settings and an occlusion time of only 15 minutes. Both the CO2 laser and the Er:YAG laser can be used to assist topical anesthesia although the CO2 laser pretreatment is experienced as more painful. In our study settings, using articaine/epinephrine solution and an occlusion time of 15 minutes, a density of 15% was more effective than 5%. Lasers Surg. Med. 50:813–818, 2018. © 2018 Wiley Periodicals, Inc.
Incorporation of photobiomodulation therapy into a therapeutic exercise program for knee osteoarthritis: A placebo‐controlled, randomized, clinical trial
Authors: de Paula Gomes Cid A. F. , Leal‐Junior Ernesto C. P. , Dibai‐Filho Almir V. , de Oliveira Adriano R. , Bley André S. , Biasotto‐Gonzalez Daniela A. , de Tarso Camillo de Carvalho Paulo
Published: May 2018

Objective

To investigate the clinical effects of incorporation of phototherapy in a therapeutic exercise program for individuals with knee osteoarthritis (OA) when compared to a group that received exercise alone and to a group that received exercise + placebo phototherapy.

Materials and Methods

This is a randomized, blinded and placebo‐controlled trial. Thus, sixty male and female individuals aged 40–80 years with knee pain in the previous 6 months participated of the study, with diagnosis of unilateral knee OA based on the criteria established by the American College of Rheumatology and radiographic confirmation and Grades 2 or 3 of the Kellgren‐Lawrence Classification. The individuals were equally divided in the groups exercise alone, exercise + active phototherapy (nine‐diode cluster device: one 905 nm super‐pulsed diode laser, four 875 nm LED and four 640 nm LED; energy per quadrant: 7.85 J; total energy: 23.55 J per session), or exercise + placebo phototherapy. Treatments were performed twice a week for 5 consecutive weeks. Patients were evaluated before and after the sessions of treatment. The outcome measures were: Western Ontario and McMaster University Osteoarthritis Index (WOMAC), Lower Extremity Functional Scale (LEFS), Numerical Rating Pain Scale (NRPS), pressure pain threshold (PPT) in two points of knee, muscle strength, and the Functional Reach Test (FRT).

Results

Exercise + active phototherapy was significantly more effective than exercise alone (mean difference [MD] = 2.75, 95% confidence interval [CI] = 3.17 to 2.32) and exercise + placebo phototherapy (MD = 2.38, 95% CI = 2.79 to 1.96) only with regard to the NRPS, considering minimal clinically important difference. No clinical significant results were found for function, the pressure pain threshold, muscle strength or balance.

Conclusions

The combination of phototherapy and an exercise program is effective at reducing pain intensity among individuals with knee osteoarthritis than exercise alone or exercise + placebo phototherapy in a short‐term protocol. Lasers Surg. Med. 50:819–828, 2018. © 2018 Wiley Periodicals, Inc.
Fractional CO2 laser treatment for vaginal laxity: A preclinical study
Authors: Kwon Tae‐Rin , Kim Jong Hwan , Seok Joon , Kim Jae Min , Bak Dong‐Ho , Choi Mi‐Ji , Mun Seok Kyun , Kim Chan Woong , Ahn Seungwon , Kim Beom Joon
Published: May 2018

Background and Objective

Various studies have investigated treatment for vaginal laxity with microablative fractional carbon dioxide CO2 laser in humans; however, this treatment has not yet been studied in an animal model. Herein, we evaluate the therapeutic effects of fractional CO2 laser for tissue remodeling of vaginal mucosa using a porcine model, with the aim of improving vaginal laxity.

Study Design/Materials and Methods

The fractional CO2 laser enables minimally invasive and non‐incisional procedures. By precisely controlling the laser energy pulses, energy is sent to the vaginal canal and the introitus area to induce thermal denaturation and contraction of collagen. We examined the effects of fractional CO2 laser on a porcine model via clinical observation and ultrasound measurement. Also, thermal lesions were histologically examined via hematoxylin–eosin staining, Masson's trichrome staining, and Elastica van Gieson staining and immunohistochemistry.

Results

The three treatment groups, which were determined according to the amount of laser‐energy applied (60, 90, and 120 mJ), showed slight thermal denaturation in the vaginal mucosa, but no abnormal reactions, such as excessive hemorrhaging, vesicles, or erythema, were observed. Histologically, we also confirmed that the denatured lamina propria induced by fractional CO2 laser was dose‐dependently increased after laser treatment. The treatment groups also showed an increase in collagen and elastic fibers due to neocollagenesis and angiogenesis, and the vaginal walls became firmer and tighter because of increased capillary and vessel formation. Also, use of the fractional CO2 laser increased HSP (heat shock protein) 70 and collagen type I synthesis.

Conclusion

Our results show that microablative fractional CO2 laser can produce remodeling of the vaginal connective tissue without causing damage to surrounding tissue, and the process of mucosa remodeling while under wound dressings enables collagen to increase and the vaginal wall to become thick and tightened. Lasers Surg. Med. 50:940–947, 2018. © 2018 Wiley Periodicals, Inc.
Poly(hydroxyl propyl methacrylate)‐b‐Poly(oligo ethylene glycol methacrylate) Thermoresponsive Block Copolymers by RAFT Polymerization
Authors: Karatza Anna , Pispas Stergios
Published: May 2018

Thermoresponsive amphiphilic poly(hydroxyl propyl methacrylate)‐b‐poly(oligo ethylene glycol methacrylate) block copolymers (PHPMA‐b‐POEGMA) are synthesized by RAFT polymerization, with different compositions and molecular weights. The copolymers are molecularly characterized by size‐exclusion chromophotography, and 1H NMR spectroscopy. Dynamic light scattering (DLS) and static light scattering (SLS) experiments in aqueous solutions show that the copolymers respond to temperature variations via formation of self‐organized nanoscale aggregates. Aggregate structural characteristics depend on copolymer composition, molecular weight, and ionic strength of the solution. Fluorescence spectroscopy experiments confirm the presence of less hydrophilic domains within the aggregates at higher temperatures. The thermoresponsive behavior of the PHPMA‐b‐POEGMA block copolymers is attributed to the particular solubility characteristics of the hydrophilic, water insoluble PHPMA block that are modulated by the presence of the water soluble POEGMA block.
Novel Theoretical Self‐Consistent Mean‐Field Approach to Describe the Conductivity of Carbon Fiber Filled Thermoplastics—PART I—Theory
Authors: Schubert Dirk W.
Published: May 2018

A novel theoretical approach is shown which yields a nonlinear differential equation for the resistivity of carbon fiber filled composites below the percolation threshold as a function of the volume fraction of the filler and the fiber orientation. The solution of the equation is given analytically and a particular value for the exponent predicted. The theoretical concept can be transferred to other composite properties.
High Fat Diets Composed of Palm Stearin and Olive Oil Equally Exacerbate Liver Inflammatory Damage and Metabolic Stress in Mice
Authors: Meidan Elena , Kolesnikov Yula , Tirosh Oren
Published: May 2018

Scope

People with fatty liver could be subject to acute infections such as sepsis. The aim of the study is to evaluate the effect of high fat diets (HFD) of olive oil and palm stearin on liver inflammation induced by lipopolysaccharides (LPS).

Methods and results

C57BL/6J male mice were treated with high fat diets with different sources of oils: palm stearin and olive oil for 8 weeks followed by LPS injection. The proinflammatory effect of olive oil was also studied using gavage treatment and IP injection of LPS. Animals fed with HFDs showed an increase in body weight, elevated blood glucose levels, and fatty liver phenotype. HFDs aggravated the effect of LPS treatment to induce inflammatory response compared to low fat diet (LFD) effect. Following HFD supplementation, LPS induced hyperinsulinemia, more liver damage than in animals that consumed LFD. In addition, both gavage and long‐term feeding with high lipids in the presence of LPS resulted in inhibition of gluconeogenic genes expression.

Conclusion

HFDs of both monounsaturated and saturated fat potentiated liver inflammation induced by LPS treatment indicate that the total amount of fat consumed is the main proinflammatory factor rather than the type of fat.
Diffusion tensor imaging of human Achilles tendon by stimulated echo readout‐segmented EPI (ste‐RS‐EPI)
Authors: Wengler Kenneth , Tank Dharmesh , Fukuda Takeshi , Paci James M. , Huang Mingqian , Schweitzer Mark E. , He Xiang
Published: May 2018

Purpose

Healing, regeneration, and remodeling of the injured Achilles tendon are associated with notable changes in tendon architecture. However, assessing Achilles microstructural properties with conventional diffusion tension imaging (DTI) remains a challenge because of very short T2/

values of the tendon. Hence, the objective of this study was to develop a novel Achilles tendon DTI protocol for a non‐invasive investigation of the changes of microstructural integrity in tendinopathy.

Methods

A novel stimulated echo readout‐segmented EPI (ste‐RS‐EPI) DTI sequence was proposed to achieve a TE of ∼14–20 ms for typical b‐values of 400–800 s/mm2 on clinical 3T MRI scanners. To further boost tendon MR signal, the Achilles was positioned at the magic angle (∼55 °) with respect to the scanner B0 field. The sensitivity of the developed protocol was evaluated in 19 healthy participants and 6 patients with clinically confirmed tendinopathy.

Results

Compared to spin echo RS‐EPI DTI protocol, ste‐RS‐EPI provided an ∼100–200% increase in Achilles MR signal. Tendinopathic Achilles demonstrated a high degree of microstructural disruption based on DTI tractography analysis, with significantly lower (P < 0.05) axial diffusivity (1.20 ± 0.19 vs. 1.39 ± 0.10 × 10−3 mm2/s), radial diffusivity (0.72 ± 0.11 vs. 0.81 ± 0.08 × 10−3 mm2/s), and mean diffusivity (0.87 ± 0.14 vs. 1.00 ± 0.07 × 10−3 mm2/s), but no significant difference in fractional anisotropy (0.38 ± 0.04 vs. 0.38 ± 0.05; P = 0.86).

Conclusion

Achilles tendon ste‐RS‐EPI DTI can non‐invasively detect the tendinopathy‐induced changes to microstructural integrity, consistent with the disruption of collagen arrangement and increased cellularity. This study demonstrated the robustness and sensitivity of the proposed protocol in Achilles tendinopathy.
Evaluation of Visceral Adipose Tissue Oxygenation by Blood Oxygen Level‐Dependent MRI in Zucker Diabetic Fatty Rats
Authors: Shi Hong‐Jian , Li Yan‐Feng , Ji Wen‐Jie , Lin Zhi‐Chun , Cai Wei , Chen Tao , Yuan Bin , Niu Xiu‐Long , Li Han‐Ying , Shu Wen , Li Yu‐Ming , Yuan Fei , Zhou Xin , Zhang Zhuoli
Published: May 2018

Objective

This study aimed to investigate the feasibility of blood oxygen level‐dependent magnetic resonance imaging (BOLD‐MRI) to evaluate visceral adipose tissue (VAT) oxygenation in Zucker diabetic fatty (ZDF) rats and its associations with systemic metaflammation.

Methods

Five‐week‐old ZDF rats and Zucker lean (ZL) rats were fed a high‐fat diet (HFD) for 18 weeks. A baseline BOLD‐MRI scan of perirenal adipose tissue was performed after 8 weeks of HFD feeding, and then the rats were randomized to receive pioglitazone or a vehicle for the following 10 weeks. At sacrifice, BOLD‐MRI scan, Hypoxyprobe‐1 injection, and circulating T helper 17 (Th17), regulatory T (Treg) cells, and monocyte subtype flow cytometry analysis were performed.

Results

HFD feeding led to a significant increase in VAT BOLD‐MRI R2* signals (20.14 ± 0.23 per second vs. 21.53 ± 0.20 per second; P = 0.012), an indicator for decreased oxygenation. R2* signal was significantly correlated with VAT pimonidazole adduct‐positive area, insulin resistance, Th17 and Treg cells, CD43 + and CD43+ + monocyte subtypes, and VAT macrophage infiltration. Pioglitazone treatment improved the insulin resistance and was associated with a delayed progression of VAT oxygenation.

Conclusions

This work demonstrated the feasibility of BOLD‐MRI for detecting the VAT oxygenation status in ZDF rats, and the BOLD‐MRI signals were associated with insulin resistance and systemic metaflammation in ZDF rats during the development of obesity.
Octa‐imidazolium POSS/quaternized polysulfone composite anion exchange membrane for alkaline fuel cell
Authors: Elumalai Vijayakumar , Dharmalingam Sangeetha
Published: May 2018

In the present study, a series of new anion exchange composite membranes were fabricated from pre‐synthesized imidazolium grafted polyhedral oligomeric silsesquioxane (IM‐POSS) with quaternary polysulfone (QPSU). Synthesized IM‐POSS were acutely characterized by Fourier‐transform infrared, NMR, scanning electron microscopy (SEM), and transmission electron microscopy (TEM) investigations to confirm the chemical structure and cubic morphologies. The IM‐POSS nanoparticles have binary function in the anion exchange membrane by providing more additional ion conducting groups (imidazolium) and by reinforcing the membrane in molecular level for overall improvement of composite membranes. The prepared composite membranes with various compositions of the IM‐POSS/QPSU were characterized by X‐ray diffraction, SEM, ion exchange capacity, water uptake (Wup), and conductivity to assure the appropriateness of their use as a solid alkaline electrolyte in anion exchange membrane fuel cell. The membrane electrode assembly was constructed using Pt anode (0.25 mg/cm2), Ag cathode (0.375 mg/cm2), and various IM‐POSS/QPSU composite membranes, which was tested in an in‐house built fuel cell setup. The membrane with 15% IM‐POSS showed the maximum power density of 309 mW/cm2. The results showed that the addition of IM‐POSS is a straight forward and effectual method to enhance the hydroxide conductivity without sacrificing other properties of the membrane. POLYM. COMPOS., 40:1536–1544, 2019. © 2018 Society of Plastics Engineers
Development of sunflower oil‐based nonisocyanate polyurethane/multiwalled carbon nanotube composites with improved physico‐chemical and microwave absorption properties
Authors: Doley Simanta , Agarwal Vivek , Bora Anindita , Borah Dipangkar , Dolui Swapan K.
Published: May 2018

In this article, we have developed sunflower oil based non‐isocyanate polyurethane (NIPU)/amine functionalized multiwalled carbon nanotube (AF‐CNT) composites. First, carbonated sunflower oil (CSFO) was obtained by solvent‐free mixture reaction of CO2 with epoxidized sunflower oil under the conditions (120°C, 40 bar) for 10 h, and characterized by FTIR, 1H NMR and 13C NMR. Then, NIPUs were synthesized by reacting the CSFO with isophorone diamine (IPDA) and subsequently, the effects of different weight percentages (0–2 wt%) of AF‐CNTs on physico‐chemical properties of the NIPU/AF‐CNT composites were examined. FT‐IR, XRD and SEM analyses confirmed the formation of the polymer nanocomposites. The results of the studies showed that polymer nanocomposites exhibited better performance than that of pristine polymer. In addition to the improvement in physico‐chemical properties, the electromagnetic interference shielding properties of the composites (1.5 wt% AF‐CNTs) were also calculated in the 8.2–12.4 GHz (X‐band) frequency range with different thicknesses. It is seen that the composite (1.5 wt%) with thickness 3 mm shows the highest microwave absorption with −17 dB at 10.86 GHz. POLYM. COMPOS., 40:E1120–E1130, 2019. © 2018 Society of Plastics Engineers
Structural origins of mechanical strengthening in poly(phenylene sulfide)/multiwalled carbon nanotube nanocomposites obtained via hot‐stretching
Authors: Lin Yunjie , Che Junjin , Pu Shuiqin , Wang Ke
Published: May 2018

This study demonstrates that solid‐state hot‐stretching is an efficacious pathway via which to achieve interfacial enhancement between poly(p‐phenylene sulfide) (PPS) and multiwalled carbon nanotubes (MWCNTs). Samples of PPS/MWCNT composite were fabricated via a two‐fold procedure involving compression molding followed by hot‐stretching, and significant mechanical reinforcement was realized in the prepared nanocomposites. The interfacial shear strength obtained under 200% stretching strain was about eight times of that obtained in the unstretched (isotropic) counterpart. Large stretching strains, such as 200%, even could induce epitaxial crystallization of PPS lamellae on the surface of MWCNT monofilaments. Moreover, strong π–π interactions between the benzene rings on the backbones of PPS and the sp2 carbon lattice surface of MWCNTs appeared for highly oriented PPS chains and MWCNT monofilaments. A comprehensive structural analysis suggested that in addition to the orientation of both the PPS crystals and MWCNTs, the change in PPS crystallinity and the confinement effect of the amorphous PPS chains, strong π–π interactions and epitaxial crystallization induced via hot‐stretching orientation are mainly responsible for the prominent mechanical reinforcement observed. POLYM. COMPOS., 40:E589–E598, 2019. © 2018 Society of Plastics Engineers
Tuning the mechanical and electrical conductivity properties of graphene‐based thermoplastic starch/poly(lactic acid) hybrids
Authors: Ferreira Willian H. , Dahmouche Karim , Andrade Cristina T.
Published: May 2018

Environmentally friendly approaches were followed to develop thermoplastic starch (TPS)/poly(lactic acid) (PLA) extruded hybrids at 70:30 and 30:70 compositions, with the incorporation of reduced graphene oxide at 1.0, 3.0, and 5.0 mass% contents. Glucose was chosen as reagent to reduce graphene oxide (GO) to the rGO sample. Theoretical models predicted that the final location of rGO was at the interface of the components. The adhesion between the polymeric phases in the hybrids, observed by scanning electron microscopy, and the improved compatibilization suggested by mechanical and dynamic mechanical analyses indicated that a large fraction of rGO platelets were at the interface. X‐ray diffraction showed that rGO acted as a nucleating agent for PLA and revealed a better dispersion of rGO lamellae within TPS. Consequently, the phase composition of the TPS/PLA/rGO hybrids played an important role on the properties of the hybrids. For the neat TPS/PLA blend at 70:30 composition, ɛmax = (4.7 ± 0.6)% and the electrical conductivity was found around 10−13 S/cm. The incorporation of rGO led to more flexible and to higher conductivity materials, with ɛmax = (15.1 ± 0.7)% and σ = 1.1 × 10−5 S/cm for the hybrid with rGO at 5.0 mass% content. POLYM. COMPOS., 40:E1131–E1142, 2019. © 2018 Society of Plastics Engineers
Time‐dependent deformation of structurally chiral polymer networks in stabilized cholesteric liquid crystals
Authors: Lee Kyung Min , Tondiglia Vincent P. , Rumi Mariacristina , White Timothy J.
Published: May 2018

Polymerization of crosslinkable liquid crystal monomers in chiral liquid crystalline media stabilizes the phase and enables distinct electro‐optic properties relative to small‐molecule analogs. Particularly interesting are cases where the polymerization forms a crosslinked polymer network that maintains a “structural” chirality. Recent reports have employed this methodology to realize a diverse set of electro‐optic responses in polymer stabilized cholesteric liquid crystals (PSCLCs) including reflection bandwidth broadening, reflection wavelength tuning, and dynamic scattering modes. It has been proposed that the mechanism at the root of these electro‐optic responses is an ion‐mediated, electromechanical deformation of the stabilizing and structurally chiral polymer network. In an effort to better understand the nature of these deformations, here we have characterized the electro‐optic response of PSCLCs with different polymer concentrations and crosslink densities. The dynamic response of PSCLCs to electric fields exhibits a time‐dependent behavior reminiscent of the creep of polymeric materials to mechanical deformations. The electro‐optic response can be described as the superposition of two contributions: the fast deformation of a relatively soft component of the polymer network (1–2 s) and the slower (10–20 s) deformation of a harder component. © 2018 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2018, 56, 1087–1093
Impact of plasma oxidation on structural features of human epidermal growth factor
Authors: Yusupov Maksudbek , Lackmann Jan‐Wilm , Razzokov Jamoliddin , Kumar Surendra , Stapelmann Katharina , Bogaerts Annemie
Published: May 2018

We perform computer simulations supported by experiments to investigate the oxidation of an important signaling protein, that is, human epidermal growth factor (hEGF), caused by cold atmospheric plasma (CAP) treatment. Specifically, we study the conformational changes of hEGF with different degrees of oxidation, to mimic short and long CAP treatment times. Our results indicate that the oxidized structures become more flexible, due to their conformational changes and breakage of the disulfide bonds, especially at higher oxidation degrees. MM/GBSA calculations reveal that an increasing oxidation level leads to a lower binding free energy of hEGF with its receptor. These results help to understand the fundamentals of the use of CAP for wound healing versus cancer treatment at short and longer treatment times.
Anthracene‐Based Colloidal Polymer Nanoparticles: Their Photochemical Ligation and Waterborne Coating Applications
Authors: Chattopadhyay Subrata , Van Damme Jonas , van den Berg Otto , Du Prez Filip
Published: May 2018

In the current work, a linear polymer, with anthracene moieties in the side chain, is prepared via step‐growth polymerization using epoxide‐amine ring opening reaction. The polymer is dispersed in water to form physically crosslinked nanoparticles (NPs), which are formed by π–π stacking of anthracene moieties. Later, the NPs are crosslinked using UV irradiation, where the anthracene units in the core are simply dimerized and crosslinked the individual chain. In this process, no significant interparticle crosslinking is observed. The higher structural integrity of the chemically crosslinked Nps is revelled via a simple swelling test. The colloidal solution is used to coat glass and silica surfaces homogeneously, which enhances the surface roughness significantly as revealed by atomic force microscope and contact angle measurements.
Preliminary Similarity Analysis on the Deformation Dynamic Response of Thin Plates Subjected to Blast and Impact Loadings
Authors: Gao Yuan , Dong Yongxiang , Xiao Lixing , Wang Fang , Feng Shunshan
Published: May 2018

The similarity and conditions for the similarity of deformation dynamic response of thin circular plates subjected to blast and impact loadings under certain conditions were studied by experimental tests and numerical simulation using air explosion and drop hammer impact loadings. The results revealed that the final deformed shapes of thin plates subjected to the two dynamic loadings are similar with less than 2 % difference in deflection and less than 8 % difference in deformed volume. The deformation similarity of plates subjected to blast and impact loadings can be achieved as the shock dimensionless number and the hammer shape satisfying given features. The deformation responses of the thin plates satisfying the constraints to blast and impact loadings are opposite. The key parameters of the blast and impact loading systems were obtained by the dimensional analysis using Buckingham π theorem. Based on these results, a similarity scheme was proposed. The numerical simulation was verified with the experimental results. In all, a novel method was established to study the similitude of analogous systems, which could be extended to other similar physical problems.
Study Design Selection in Early Clinical Anti‐Hyperglycemic Drug Development: A Simulation Study of Glucose Tolerance Tests
Authors: Ibrahim Moustafa M. A. , Ghadzi Siti M. S. , Kjellsson Maria C. , Karlsson Mats O.
Published: May 2018

In antidiabetic drug development, phase I studies usually involve short‐term glucose provocations. Multiple designs are available for these provocations (e.g., meal tolerance tests (MTTs) and graded glucose infusions (GGIs)). With a highly nonlinear, complex system as the glucose homeostasis, the various provocations will contribute with different information offering a rich choice. Here, we investigate the most appropriate study design in phase I for several hypothetical mechanisms of action of a study drug. Five drug effects in diabetes therapeutic areas were investigated using six study designs. Power to detect drug effect was assessed using the likelihood ratio test, whereas precision and accuracy of the quantification of drug effect was assessed using stochastic simulation and estimations. An overall summary was developed to aid designing the studies of antihyperglycemic drug development using model‐based analysis. This guidance is to be used when the integrated glucose insulin model is used, involving the investigated drug mechanisms of action.
Flexible High Density Active Neural Implants Combining a Distributed Multiplexing Transceiver Architecture with Biocompatible Technology
Authors: Marcoleta Juan Pablo , Nogueira Waldo , Froriep Ulrich Paul , Doll Theodor
Published: May 2018

Precise localization of brain tissue causing severe neurological conditions requires subdural recording arrays with high electrode density and low mechanical stiffness compliant with the brain tissue. However, most arrays currently used − such as clinical ECoG grids − are rather stiff and limited in spatial resolution. To overcome these constrains a novel architecture is proposed using delocalized electronic (de)multiplexer grains. Here, their functional units are described in both hard‐ and software, and tested in simulations and experimentally. The results show that in case of a 100 × 100 mm ECoG array with lower mechanical stiffness, inter‐electrode distances <1 mm can be achieved. Taking parasitic capacitances into account, a signal resolution of 100 μV is reached with an inter‐channel timing resolution of 200 ns, which in our model corresponds to tissue localization as precise as 1.2 mm. For clinical application of envisaged 5000 electrodes, a preselection mechanism and routes for adoption of this technology toward cochlear implants and brain computer interfaces are presented.
Ab Initio Prediction of Mechanical and Electronic Properties of Ultrahigh Temperature High‐Entropy Ceramics (Hf0.2Zr0.2Ta0.2M0.2Ti0.2)B2 (M = Nb, Mo, Cr)
Authors: Wang Ya‐Ping , Gan Guo‐Yong , Wang Wei , Yang Yan , Tang Bi‐Yu
Published: May 2018

High‐entropy metal diborides (Hf0.2Zr0.2Ta0.2M0.2Ti0.2)B2 (M = Nb, Mo, Cr) are a new class of ultrahigh temperature ceramics. The novel structural, mechanical, and electronic properties of (Hf0.2Zr0.2Ta0.2M0.2Ti0.2)B2 (M = Nb, Mo, Cr) are studied within density functional theory, with the compositional disorder being treated using the special quasi‐random structures technique. The elastic stiffness constants Cij, as well as bulk, shear and Young's modulus of (Hf0.2Zr0.2Ta0.2M0.2Ti0.2)B2 (M = Nb, Mo, Cr) are studied to estimate the mechanical properties. The ductility is also investigated from several criterions, showing that (Hf0.2Zr0.2Ta0.2M0.2Ti0.2)B2 (M = Nb, Mo, Cr) is still intrinsically brittle. The high Debye temperature of (Hf0.2Zr0.2Ta0.2M0.2Ti0.2)B2 (M = Nb, Mo, Cr) indicates the strong interatomic interactions and good thermal conductivity. The detailed investigations of electronic structure reveal that covalent and metallic bonds are respectively formed in the boron layer and the metal layer, mixed ionic and covalent bonds are formed between the metals and boron interlayer.
Improving the Silicon Surface Passivation by Aluminum Oxide Grown Using a Non‐Pyrophoric Aluminum Precursor
Authors: Lee Chang‐Yeh , Wang Shaozhou , Cui Xin , Zhang Tian , Deng Rong , Khoo Kean T. , Hoex Bram
Published: May 2018

In this work, an alternative nonpyrophoric Al‐precursor [dimethylaluminum isopropoxide (DMAI)] is used to deposit Al2O3 on p‐type c‐Si by plasma‐enhanced and thermal atomic layer deposition (ALD). Al2O3 films grown by thermal ALD provide a relatively modest level of crystalline silicon surface passivation compared to their plasma‐assisted ALD grown counterparts. This difference is attributed to a significant difference in the interfacial SiOx film as identified by Brewster's angle Fourier transform infrared spectroscopy. The energy barrier for DMAI to react with Si‐H groups on the surface is significantly lower compared to TMA, which impedes the formation of the interfacial SiOx layer. As thermal ALD is the strongly preferred method in the photovoltaic industry, there is a strong incentive to improve the performance of the thermal ALD process to allow for the application of this intrinsically safer Al2O3 deposition process. A chemically grown thin oxide is shown to significantly improve the level of surface passivation provided by the thermal ALD Al2O3 film resulting in an increase in implied open circuit voltage from 653 to 723 mV. This surface pretreatment thus solves a major barrier for the application of this intrinsically safer process in the photovoltaic industry.
Integrated QMMM and Monte Carlo methods for analysis of adsorptive interactions between goethite cluster, carbon nanotubes, and arsenate
Authors: Ha Nguyen Ngoc , Cam Le Minh , Thi Thu Ha Nguyen , Jiang Zhong‐Tao , El‐Harbawi Mohanad , Yin Chun‐Yang
Published: May 2018

Iron‐immobilized nanoporous carbon is a well‐known adsorbent used in treating arsenic‐contaminated waters. In this contribution, we present findings on the adsorptive interactions and dynamics of arsenate–goethite cluster ([FeO(OH)]6) with carbon nanotubes (CNTs) using hybridized quantum mechanics/molecular mechanics (QMMM) calculations. The CNTs adsorption mechanism is of interest since a better understanding of the fundamental interactions between arsenate, goethite, and carbon surfaces would translate to advances in CNT‐based adsorbent production and utilization. Novel applications of general amber force field (GAFF) and isobaric‐isothermal Gibbs ensemble Monte Carlo (NpT‐GEMC) methods are described. By the abovementioned methods, we postulate that the [FeO(OH)]6/CNT‐2.3 (diameter 2.3 nm ‐ mesoporous) system enhances the qualitative (i.e., improved chemisorption) rather than the quantitative adsorptive aspect (i.e., total
ions adsorbed) in comparison to the [FeO(OH)]6/CNT‐1.6 (diameter 1.6 nm ‐ microporous) system.
Identifying a possible factor for the increased newborn size in singleton pregnancies after assisted reproductive technology using cryopreserved embryos, in comparison with fresh embryos
Authors: Ishii Rena , Shoda Akiko , Kubo Michiyo , Okazaki Satiko , Suzuki Minori , Okawa Riho , Enomoto Megumi , Shitanaka Manami , Fujita Yoko , Nakao Kazuki , Shimada Nobutaka , Horikawa Michiharu , Negishi Hiroaki , Taketani Yuji
Published: May 2018

Purpose

To determine whether the cycle regimens that are used for endometrial preparation are associated with the birthweight (BW) after assisted reproductive technology (ART) using frozen‐thawed embryo transfer (FET).

Methods

The BW of singletons who were born by ART using FET was compared retrospectively, according to whether a FET was conducted in a hormone replacement therapy cycle (HRT, n = 403) or an ovulatory cycle (OVL, n = 117). The BW after timed intercourse (NAT, n = 162) also was investigated.

Results

There were no significant differences in the age of the mothers, percentage of primiparas, gestational periods, Body Mass Index, and sex ratio between the HRT and OVL cycles. The average BW from HRT was significantly greater than that of OVL. The BW from HRT was also greater, compared with NAT, while statistical significance was not achieved between OVL and NAT. The putative factors affecting the BW, such as ovarian stimulation protocols, endometrial thickness, and the stage and quality of embryos, could not explain the difference in the BW between the HRT and OVL cycles.

Conclusion

An increased BW from ART using FET seems to be ascribable to conditions of the endometrium, but not cryopreservation procedures per se, which might provide a mechanistic framework for understanding heavier neonates who are born by FET.
Deciphering the Interaction of 5,7‐Dihydroxyflavone with Hen‐Egg‐White Lysozyme through Multispectroscopic and Molecular Dynamics Simulation Approaches
Authors: Das Sourav , Khanikar Portia , Hazarika Zaved , Rohman Mostofa Ataur , Uzir Antara , Nath Jha Anupam , Singha Roy Atanu
Published: May 2018

In recent times, research based on the bio‐active flavonoid, chrysin has shown its potential therapeutic applications such as anti‐diabetic, neuroprotective, anti‐asthmatic, anti‐depressant, etc. In order to understand its molecular recognition process, we studied its interaction with hen egg white lysozyme (HEWL) at physiological conditions. Chrysin (5,7‐Dihydroxyflavone) was able to quench the intrinsic fluorescence of HEWL through static quenching mechanism and the binding constant (Kb) was found to be (4.390±0.088 ×104) M−1 at 298 K and it decreased with the increase in temperature. The value of thermodynamic parameters such as ΔH (‐17.154±0.872) kJ mol−1 and ΔS (+31.267±3.151) J K−1 mol−1 indicated that hydrogen bonding and hydrophobic forces played a central role in the complexation process. Alteration in the Trp micro‐environment was induced due to the incorporation of chrysin in the binding site as indicated by synchronous and three dimensional (3D) fluorescence studies. FT‐IR and CD studies revealed that the secondary structure of HEWL was altered on chrysin binding, which resulted in an increase in the α‐helical stability of the protein. Chrysin inhibited the enzymatic activity of HEWL against M. lytus. Molecular docking and molecular simulation studies revealed that hydrogen bonding and hydrophobic forces played a vital role in complexation process. This study provides substantial insight into the binding of a bio‐active flavonoid (chrysin) with a carrier protein (HEWL).
Au‐Mediated Composite In2S3–Au–BiVO4 with Enhanced Photocatalytic Activity for Organic Pollutant Degradation
Authors: Wu Di , Bao Shenyuan , Wang Zheng , Zhang Zhizhong , Tian Baozhu , Zhang Jinlong
Published: May 2018

A ternary composite photocatalyst In2S3–Au–BiVO4 was fabricated by stepwise photo‐reduction and deposition−precipitation methods. It was found that the Au nanoparticles (NPs) were selectively anchored on the {010} facets of decahedral BiVO4 crystals due to the oriented accumulation of electrons during the photo‐reduction stage. Based on the strong interaction between S−Au, In2S3 was loaded on the surface of Au NPs on BiVO4 {010} facets. Photocatalytic degradations of organic contaminants Rhodamine B and phenol indicated that In2S3–Au–BiVO4 showed evidently improved visible light photocatalytic activity than BiVO4, Au–BiVO4, and In2S3–BiVO4. On the basis of the photoelectrochemical and photoluminescence (PL) analyses, it can be inferred that the facet hetero‐juction and Au‐mediated composite structures of In2S3–Au–BiVO4 can improve the separation efficiency of photo‐generated carriers as well as make the carriers keep higher redox ability. The radical trapping experiments indicated that for In2S3–Au–BiVO4, •OH, h+, and •O2− are the main reactive species which take part in the organic contaminant degradation.
Synthesis of Recyclable Hyperbranched Polymers with High Efficiency of Promoting Degradation of Epoxy Resins
Authors: Wang Luping , Chen Sufang , Cheng Juan , Guo Wenqiang , Wang Yimei , Miao Menghe , Zhang Daohong
Published: May 2018

Epoxy resins has been the largest industrial thermosetting resins due to their excellent performance. But the degradation and recycling of large amount of cured epoxy resins wastes is still a challenge, inevitably causing serious pollution to the environment. Here, we represent a feasible method to synthesize recyclable hyperbranched polymers (epoxy‐ended hyperbranched polymers, DEHP‐n, n=1, 2, 3 and 4). DEHP‐n can be self‐crosslinked or self‐cured to form high performance films, and the cured film can be completely and rapidly degraded in solution of DMF and H2O2 at low temperature (90 oC), showing excellent recyclability. High performance molecular composites without phase‐separation can be obtained by blending DEHP‐n and diglycidyl ether bisphenol A (DGEBA). It is much important that DEHP‐n not only substantially improve tensile strength of about 67% and toughness of about 154% on DGEBA, and but also promote the degradation degree about 3 times when the composites contains only about 12 wt% DEHP‐n. The degradation mechanism of cured DEHP‐n and DEHP‐n/DGEBA composites was analyzed by GC‐Mass of their pyrolysis products. The multifunctional DEHP‐n may open avenue for synthesis of novel recycling epoxy resins and degradation of conventional epoxy resins, besides simultaneous improvement of strength and toughness.
A Mechanoresponsive Fluorescent Mg‐Zn Bimetallic MOF with Luminescent Sensing Properties
Authors: Wu Zhao‐Feng , Huang Xiao‐Ying
Published: May 2018

Presented here are the synthesis, crystal structure and fluorescent properties of a Mg−Zn bimetallic metal organic framework (MOF), namely [MgZn(1,4‐NDC)2(DMF)2 (1, 1,4‐NDCH2=1,4‐naphthalene dicarboxylic acid). Compound 1 possesses a three‐dimensional (3D) structure constructed by the 1,4‐NDC linkers bridging the infinite one dimensional (1D) chain of [–Mg–(COO)2–Zn–(COO)2–]n. Photoluminescence studies indicated that 1 shows a grinding mechanoresponsive fluorescence changing from green to blue emission. Notably, thus far there is no investigation on the mechanoresponsive fluorescent properties of Mg‐based heterometallic MOF. Moreover, the blue emitting powdered sample could not only act as an effective fluorescence sensor for Fe3+/Cu2+/CrO42− ions, but also exhibit sensitive fluorescent detection for the low‐concentration CS2 and nitro‐containing compounds. This work may provide a certain guiding significance for exploring functional heterometallic fluorescent MOFs based on the environmentally friendly and abundant Mg2+.
Boosting the Film Quality by Simultaneously Pre‐wetting the PbI2 Film and Ostwald Ripening the MAPbI3 Film with DMSO Addition into MAI Solution
Authors: Ha Jiao , Dong Guohua , Yang Yulin , Sheng Li , Zhang Wenzhi , Xia Debin , Fan Ruiqing , Luan Tianzhu
Published: May 2018

Generally, the typical two‐step sequential spin‐coating deposition (TSSD) method is not compatible with the preparation of the high‐efficiency perovskite solar cells due to the low film quality. Herein, we introduced trace amounts of DMSO into the MAI/isopropanol solution aiming at improving the quality of perovskite film fabricated with TSSD method. Based on this strategy, the perovskite film formed with an optimal DSMO addition ratio of 0.5 v% exhibits a significant higher film quality with improved optical properties than that of the pristine one, which can be attributed to an optimized crystallization process including pre‐wetting the PbI2 film and simultaneously Ostward ripening the formed perovskite crystals induced by the DMSO addition. Thus the corresponding perovskite solar cells yielded a higher power conversion efficiency as high as 15.39% comapred with the pristine counterpart, finally achieving a 14.42% enhancement of the PCE. In conclusion, this work provides a facile and effective strategy to fabricate high‐quality perovskite films with TSSD method by introducing some polar solvents.