bluuebunny/crossref_metadata_2025 huggingface dataset:
Occurrence of water ponding on soil surfaces depending on infiltration rates on Mongolian rangeland
Authors: Miyasaka Katori , Shiozawa Sho , Nishida Kazuhiro , Batsukh Siilegmaa , Yoshida Shuichiro , Jamsran Undarmaa
Published: August 2017

The occurrence of water ponding on soil surfaces during and after heavy rainfall produces surface run‐off or surface water accumulation in low‐lying areas, which might reduce the water supply to soils and result in a reduction of the soil water that plants can use, especially in arid climates. On Mongolian rangeland, we observed ponded water on the surface of a specific soil condition subjected to a heavy rainfall of 30 mm/hr. By contrast, ponded water was not observed for the same type of soil where livestock grazing had been removed for 6–8 years via a fence or for nearby soil containing less clay. We measured the infiltration rate (the saturated hydraulic conductivity of the surface soil, Ks) of the three sites by applying ponded water on the soil surface (an intake rate test). The results showed that Ks in the rangeland was lower than the rainfall intensity in the site where water ponded on the soil surface; however, Ks of the soil inside of the fence has recovered to 3 times that of the soil outside of the fence to exceed the rainfall intensity. Heavy rainfall that exceeds the infiltration rate occurs several times a year at the livestock grazing site where we observed ponded water. Slight water repellency of the soil reduces rain infiltration to increase the possibility of surface ponding for the soil.
Roadmap for investigating epigenome deregulation and environmental origins of cancer
Authors: Herceg Zdenko , Ghantous Akram , Wild Christopher P. , Sklias Athena , Casati Lavinia , Duthie Susan J. , Fry Rebecca , Issa Jean‐Pierre , Kellermayer Richard , Koturbash Igor , Kondo Yukata , Lepeule Johanna , Lima Sheila C.S. , Marsit Carmen J , Rakyan Vardhman , Saffery Richard , Taylor Jack A. , Teschendorff Andrew E. , Ushijima Toshikazu , Vineis Paolo , Walker Cheryl Lyn , Waterland Robert A. , Wiemels Joe , Ambatipudi Srikant , Degli Esposti Davide , Hernandez‐Vargas Hector
Published: August 2017

The interaction between the (epi)genetic makeup of an individual and his/her environmental exposure record (exposome) is accepted as a determinant factor for a significant proportion of human malignancies. Recent evidence has highlighted the key role of epigenetic mechanisms in mediating gene–environment interactions and translating exposures into tumorigenesis. There is also growing evidence that epigenetic changes may be risk factor‐specific (“fingerprints”) that should prove instrumental in the discovery of new biomarkers in cancer. Here, we review the state of the science of epigenetics associated with environmental stimuli and cancer risk, highlighting key developments in the field. Critical knowledge gaps and research needs are discussed and advances in epigenomics that may help in understanding the functional relevance of epigenetic alterations. Key elements required for causality inferences linking epigenetic changes to exposure and cancer are discussed and how these alterations can be incorporated in carcinogen evaluation and in understanding mechanisms underlying epigenome deregulation by the environment.
Late Quaternary environmental dynamics in the Atacama Desert reconstructed from rodent midden pollen records
Authors: de Porras M. E. , Maldonado A. , De Pol‐Holz R. , Latorre C. , Betancourt J. L.
Published: August 2017

In the past two decades, much has been learned about the late Quaternary climate history of the Atacama Desert with some details still unclear about the seasonality, timing and extent of wet and dry phases. Modern climate studies reveal that, far from exhibiting a unique pattern, seasonal precipitation originates from many sources and mechanisms. For the last 16 ka, we attempt to sort out these complexities in pollen records from four fossil rodent midden series spanning 22°–25°S in northern Chile. Widespread wet conditions prevailed during the late Pleistocene and early Holocene, particularly between 13 and 9 ka, evidenced by <400 m lowering of pollen zones (plant communities) compared to today. Regional differences in the timing and magnitude of this displacement may be related to the prevailing source (tropical/extra‐tropical) or mode (NNW/SE) of tropical precipitation through time. Wet conditions persisted well into the early Holocene, lasting ∼1–1.5 ka longer than previously suggested. The pollen record suggests extreme drying ∼8 ka, possibly associated with a northward shift of the Inter Tropical Convergence Zone, tracking minimum insolation values at subtropical latitudes during the austral summer. The establishment of conditions similar to today happened ∼4 ka. Copyright © 2017 John Wiley & Sons, Ltd.
SERS, Raman, and DFT analyses of fentanyl and carfentanil: Toward detection of trace samples
Authors: Leonard Jennifer , Haddad Abed , Green Omar , Birke Ronald L. , Kubic Thomas , Kocak Ali , Lombardi John R.
Published: August 2017

We examine the normal Raman and the surface‐enhanced Raman spectra of fentanyl and carfentanil. As an aid in the assignment of the spectral lines, we present a density functional theory calculation. Although Raman spectroscopy is a valuable analytic tool for the detection and identification of molecular species, it is a weak effect and requires specialized equipment for detection of trace samples. We therefore turn to surface‐enhanced Raman spectroscopy, which utilizes the large enhancement of the Raman signal endowed by proximity to silver or gold nanoparticles. The enhancement factor (EF) obtained in this experiment is ≥1.6 × 105. This points the way towards future development of a simple and sensitive technique for the detection of analytes in trace quantities, particularly for wider application in forensic science.
Physicochemical and rheological characterization of different Carnoy's solutions applied in oral and maxillofacial surgery
Authors: Carvalho Francisco Samuel Rodrigues , Feitosa Victor Pinheiro , da Cruz Fonseca Said Gonçalves , de Vasconcelos Araújo Thiago Dias , Soares Eduardo Costa Studart , Fonteles Cristiane Sá Roriz , Ribeiro Thyciana Rodrigues , Costa Fábio Wildson Gurgel
Published: August 2017

Carnoy's solution has been widely undertaken as adjunctive therapy for benign odontogenic tumors. Although its outcomes were highly investigated, little information is available regarding its mechanism of action and the role of chloroform in composition. The aim of this study was to characterize Carnoy's solution (with and without chloroform) in order to survey its physicochemical and pharmacological properties. UV/Vis spectroscopy, Raman microspectroscopy, viscosity assessment, pH analysis, and ion (Fe3+) concentration were studied. All solutions were prepared by the same operator and assayed at each 7 days within a 4‐week period. All solutions depicted acidic pH whereas the viscosity was increased by the addition of chloroform. Starting in the seventh day after preparation, solutions with chloroform showed iron precipitation when nonfiltered. Carnoy's solution without chloroform was stable during the survey period as evidenced by Raman spectroscopy. In conclusion, Carnoy's solution possesses an acidic characteristic, it is stable when stored at room temperature, and precipitates iron salts when in the presence of chloroform in a nonfiltered solution. The chloroform increases the viscosity of the solution and makes its pH slightly more acidic when compared to the Carnoy's solution without chloroform. Raman spectroscopy favored the evaluation of components' stability in solutions by using the spectra analysis and the established correlations between the peaks in different periods.
Direct imaging exposure equipment with high overlay accuracy for flexible substrate in roll‐to‐roll method
Authors: Kito Yoshiaki , Hori Masakazu , Hayashida Yosuke , Suzuki Tomonari , Komiyama Hiroki , Watanabe Tomoyuki , Kurashige Takahiro , Kato Masaki , Nara Kei
Published: August 2017

In order to fabricate thin‐film transistors on a flexible substrate, it is required to overlay patterns with high alignment accuracy. A polymer film can be deformed greatly and easily through thin‐film transistor fabrication processes because the glass transition point of a polymer film is below the maximum temperature of the processes. Furthermore, low stiffness of a polymer film can cause deformation when the polymer film is loaded on a working holder. These matters make it difficult to make patterns directly on a polymer film with high alignment accuracy. We proposed three concepts that solve three technical issues in order to directly make patterns with high overlay accuracy on a flexible film without a support substrate. We developed roll‐to‐roll exposure equipment with high overlay accuracy for a flexible substrate. Using this equipment, we succeeded to directly make patterns on a PET film, achieving a resolution of less than 6‐μm line and space pattern and an overlay accuracy of less than ±5 μm.
Theoretical Study of the Reaction of Carbonyl Oxide with Nitrogen Dioxide: CH2OO + NO2
Authors: Vereecken L. , Nguyen H. M. T.
Published: August 2017

The reaction mechanism of the reaction of the Criegee intermediate CH2OO with NO2 was investigated using quantum chemical and theoretical kinetic methodologies. The reaction shows a rich chemistry, though the number of channels that effectively contribute at room temperature is limited. The theoretical characterization of the entrance transition states was hampered by strongly multireference wave functions. The predicted rate coefficient k(298 K) = 4.4 × 10−12 cm3 molecule−1 s−1 thus carries a large uncertainty, but is in agreement with literature data. We find that the CH2OO + NO2 reaction reacts by adduct formation, near‐exclusively forming nitro‐peroxy radicals, •OOCH2NO2. These will react as other alkylperoxy radicals in the atmosphere, ultimately generating CH2O and regenerating NO2 in most reaction conditions. The product predictions contrast with earlier experimental work showing NO3 formation, but support other observations of adduct products.
Kinetic Study and Mechanism Hydrolysis of 4‐Bromo‐3,5 dimethylphenyl N‐methylcarbamate in Aqueous Media
Authors: Attig Jihène Ben , Ouertani Randa , Megriche Adel , Hamida Néjib Ben , El Atrache Latifa Latrous
Published: August 2017

Degradation via hydrolysis is among the main transformation pathways and particularly for N‐methylcarbamates. Carbamate pesticide hydrolysis is known to proceed through alkaline catalysis, with reaction of the hydroxide ion with the carbonyl function or with abstraction of hydrogen in the α position with respect to the carbonyl. This reaction leads to the formation of methylamine and corresponding phenol. In this respect, the reaction kinetics of 4‐bromo‐3,5‐dimethylphenyl N‐methylcarbamate (BDMC) hydrolysis have been investigated in alkaline solution using a spectrophotometric technique and reversed phase liquid chromatography. The kinetic constants were determined following a proposed pseudo–first‐order kinetic model. The positive activation entropy ΔS≠ = +35.73 J mol−1 K−1 and the absence of general base catalysis indicated an unimolecular elimination conjugate base (E1cB) hydrolytic mechanism involving the formation of methyl isocyanate. This result was confirmed by the fact that BDMC fits well into brönsted and Hammett lines, obtained for a series of substituted N‐methylcarbamate whose decomposition in aqueous media was established to follow an E1cB mechanism.
Bed disturbance below dams: observations from two Mediterranean rivers
Authors: Lobera Gemma , Andrés‐Domenech Ignacio , López‐Tarazón José A. , Millán‐Romero Pedro , Vallés Francisco , Vericat Damià , Batalla Ramon J.
Published: August 2017

River‐bed disturbance and associated sedimentary processes such as particle mobility are central elements to assess river ecosystem functioning. Dams change river dynamics affecting the magnitude and frequency of biophysical elements that depend on them. This paper examines the effects of two dams different in size, management, and location, on the flow regime, flood competence, and bed disturbance in two contrasting Mediterranean rivers, the Ésera and the Siurana. For this purpose, two reaches on each river were monitored upstream and downstream from reservoirs. Several monitoring and modeling techniques were used to characterize flow competence, particle entrainment, and the volumes of sediments eroded and deposited after floods. The flow regime of the Ésera has been modified from nivo‐pluvial regime, typical of humid mountainous environments, to that observed in dry semiarid regions, in which high magnitude but low frequency floods are the dominant processes. Conversely, the flow regime of the Siurana has changed from a typical Mediterranean stream to a regime observed in more temperate environments, with more permanent and stable flows. Both rivers show notably physical changes, with channels clearly less dynamic below the dams. The lack of competent flows together with the sediment deficit associated with the dams has led to less active fluvial environments (reduced particle mobility and bed scour dynamics), a fact that affects instream habitat structure (more uniform grain size distribution, less physical heterogeneity, more stable flows), overall contributing to the degradation of the stream corridor and the subsequent environmental deterioration of the whole fluvial landscape. Copyright © 2017 John Wiley & Sons, Ltd.
Physical realization of Schell‐model sources using a fast steering mirror
Authors: Hyde Milo W. , Bose‐Pillai Santasri R. , Xiao Xifeng , Voelz David G.
Published: August 2017

A simple optical system is built to quickly realize partially coherent sources for directed energy applications. The apparatus implements a recently developed technique in which any uniformly correlated or Schell‐model source can be generated by summing many statistically independent randomly tilted beams. This result means that only a tip‐tilt or fast steering mirror (FSM) is needed to realize Schell‐model sources, which in contrast to existing synthesis techniques, is both fast and flexible. A brief review of the theory necessary to understand and implement the tilt‐only synthesis technique is presented. The FSM apparatus is then described. Lastly, experimental results of a Schell‐model source are compared with theoretical predictions to validate both the synthesis technique and FSM apparatus.
Metal cover design of mobile phone for wireless power transfer
Authors: Kim Jae Hee , Ahn Chi‐Hyung
Published: August 2017

This letter proposes a method of designing a metal cover of mobile phone for wireless power transfer (WPT). To investigate the effect of metal cover on WPT, the efficiency is extracted by changing the size and shape of the metal cover. As a result, the factor of reducing the efficiency of the WPT is the cover design adjacent to the receiving coil. Two cover designs are proposed to maximize efficiency when covering the entire mobile phone with metals according to the via positions. The first design is to divide the metal cover into five metal patches. A large metal patch is located in the middle and two small metal patches are placed at the top and bottom respectively. The second design is to divide the metal cover into three metal patches and the metal patches are placed at the top, middle, and bottom. The efficiency of the WPT is measured by fabricating the proposed structures. At the frequency of 6.78 MHz, the measured efficiency is 65% for the first design, and 63% for the second design.
325 GHz CMOS power detector integrated with patch antenna
Authors: Yi C. , Choi S. H. , Kim M.
Published: August 2017

A 325 GHz power detector integrated with a microstrip patch antenna is fabricated using 65‐nm CMOS technology. Measurements on the detector pixel show responsivity of 41.2 V/W and noise equivalent power of 36.8 pW/Hz0.5. Two breakout circuits including a detector block and a patch antenna are additionally tested to understand the pixel performance. This analytical procedure should yield more accurate future detector pixel designs.
Dual‐end opened slot antenna design for dual‐band WLAN uses on handsets
Authors: Chang Chih‐Kai , Yao Chi‐Yuan , Liao Wen‐Jiao
Published: August 2017

A novel slot antenna configuration is proposed for applications on mobile terminals. The slot has both ends opened and can be placed on circuit board edges or incorporated with a handset's metal body. The antenna is loaded with one capacitor at the slot's opening and an inductor right next to the feed. Functions of loadings include size reduction, band broadening, and matching improvement. A compact design of 15 mm × 5 mm is devised for dual‐band WLAN uses. Simulated and measured results validate that good matching and radiation efficiency are achieved with moderately directive patterns in both bands. A two‐antenna scheme is also provided for MIMO uses. A mobile device can take advantage of the proposed antenna's compact volume and directive pattern to achieve good isolation and diversity performances.
A high‐linearity Doherty power amplifier using Metamaterial based on ferroelectric ceramics
Authors: Zhao Shiwei , Ren Yi , Xu Yuehang
Published: August 2017

In this letter, a new Metameterial using ferroelectric ceramics is proposed to improve the linearity of the Doherty power amplifier (DPA). The conventional λ/4 transmission line is substituted by the periodic Metamaterial cell, which the impedance inversion can be performed by the proposed structure. Meanwhile, the second and higher order harmonics of the main amplifier is suppressed by this structure. In addition, the phase of Metamaterial can be changed to desired value by modifying the voltage of Barium Strontium Titanate (BST) because the loaded Metamaterial cell is based on BST. Accordingly, the AM‐PM distortion of the total DPA can be corrected by tuning the voltage of BST. Experiment results show that the third‐order inter‐modulation distortion (IMD3) of the proposed DPA can be reduced by 20 dB compared with the conventional DPA.
A new filter antenna using improved stepped impedance hairpin resonator
Authors: Feng Dan , Zhai Huiqing , Xi Lei , Zhang Kedi , Yang Dong
Published: August 2017

In this letter, a filter antenna based on novel wide stop‐band low‐pass filter has been presented. The introduction of mushroom cell makes smaller structure and wider stop‐band of the antenna. The filter antenna works in the frequency from 1.8 to 2 GHz (10.5%), and exhibits a good out‐band rejection characteristic that the maximum frequency of the stop band is 13 GHz, which is 6.8 times of the central frequency. The measured results show a good agreement with simulated results.
Dual‐wideband band pass filter using folded cross‐stub stepped impedance resonator
Authors: Firmansyah Teguh , Praptodinoyo Supriyanto , Wiryadinata Romi , Suhendar Suhendar , Wardoyo Siswo , Alimuddin Alimuddin , Chairunissa Cindy , Alaydrus Mudrik , Wibisono Gunawan
Published: August 2017

In this letter, a dual‐wideband band pass filter (DW‐BPF) using cross‐stub stepped impedance resonator (CS‐SIR) was simulated, fabricated, and measured accordingly. The CS‐SIR was used to replace the conventional half‐wavelength open stub resonators. Compare to the conventional resonator, the CS‐SIR resonator has a wider fractional bandwidth and ease of fabrication. Furthermore, the DB‐BPF was fabricated on microstrip with ɛr = 4.4, h = 0.8 mm, and tan δ = 0.0265. The DW‐BPF with CS‐SIR achieves transmission‐coefficients/fractional‐bandwidth of 0.22 dB/94.19% and 1.87 dB/33.52% at 1.14 GHz and 2.31 GHz, respectively. In order to reduce the filter size, a folded CS‐SIR (FCS‐SIR) was also proposed. As a result, this BPF size was reduced to 53%, with the BPF size of 0.30 λG2 and 0.14 λG2 for DW‐BPF with CS‐SIR and DW‐BPF with folded CS‐SIR, respectively. The λG is the wavelength at the first frequency. Further, the DW‐BPF with FCS‐SIR achieves transmission coefficients/fractional bandwidth of 0.19 dB/89.08% and 1.29 dB/31.90% at 1.21 GHz and 2.41 GHz, respectively. Measured results are in a very good agreement with the simulated results.
1.5 µW wake‐up‐receiver for biotelemetry applications
Authors: Whitehall Sean E. , Saavedra Carlos E.
Published: August 2017

This article presents a microwave wake‐up receiver for biotelemetry applications. The circuit is designed using 130 nm CMOS technology and it consists of a passive amplification front end filter, envelope detector and baseband frequency amplifier with variable feedback filtering. The receiver is designed to operate at 7.6 GHz and measured results show that it has a sensitivity of −40 dBm while drawing just 3 μA from a 0.5 V supply. The presented work has the smallest known area and exhibits a competitive tradeoff between DC power, sensitivity, and bit rate.
A framework based on hidden Markov trees for multimodal PET/CT image co‐segmentation
Authors: Hanzouli‐Ben Salah Houda , Lapuyade‐Lahorgue Jerome , Bert Julien , Benoit Didier , Lambin Philippe , Van Baardwijk Angela , Monfrini Emmanuel , Pieczynski Wojciech , Visvikis Dimitris , Hatt Mathieu
Published: August 2017

Purpose

The purpose of this study was to investigate the use of a probabilistic quad‐tree graph (hidden Markov tree, HMT) to provide fast computation, robustness and an interpretational framework for multimodality image processing and to evaluate this framework for single gross tumor target (GTV) delineation from both positron emission tomography (PET) and computed tomography (CT) images.

Methods

We exploited joint statistical dependencies between hidden states to handle the data stack using multi‐observation, multi‐resolution of HMT and Bayesian inference. This framework was applied to segmentation of lung tumors in PET/CT datasets taking into consideration simultaneously the CT and the PET image information. PET and CT images were considered using either the original voxels intensities, or after wavelet/contourlet enhancement. The Dice similarity coefficient (DSC), sensitivity (SE), positive predictive value (PPV) were used to assess the performance of the proposed approach on one simulated and 15 clinical PET/CT datasets of non‐small cell lung cancer (NSCLC) cases. The surrogate of truth was a statistical consensus (obtained with the Simultaneous Truth and Performance Level Estimation algorithm) of three manual delineations performed by experts on fused PET/CT images. The proposed framework was applied to PET‐only, CT‐only and PET/CT datasets, and were compared to standard and improved fuzzy c‐means (FCM) multimodal implementations.

Results

A high agreement with the consensus of manual delineations was observed when using both PET and CT images. Contourlet‐based HMT led to the best results with a DSC of 0.92 ± 0.11 compared to 0.89 ± 0.13 and 0.90 ± 0.12 for Intensity‐based HMT and Wavelet‐based HMT, respectively. Considering PET or CT only in the HMT led to much lower accuracy. Standard and improved FCM led to comparatively lower accuracy than HMT, even when considering multimodal implementations.

Conclusions

We evaluated the accuracy of the proposed HMT‐based framework for PET/CT image segmentation. The proposed method reached good accuracy, especially with pre‐processing in the contourlet domain.
Chitosan biocomposites with enzymatically produced nanocrystalline cellulose
Authors: Grząbka‐Zasadzińska Aleksandra , Smułek Wojciech , Kaczorek Ewa , Borysiak Sławomir
Published: August 2017

Several fungal and bacterial strains are known to be able to degrade polymeric chains of cellulose. In this research, two polymorphic forms of celluloses, Cellulose I (C I) and Cellulose II (C II), were incubated with Ochrobactrum anthropi strain producing the cellulolytic enzymes. In the result, nanocrystalline celluloses with distinctive particle sizes distributions, as well as intact supermolecular and chemical structures were produced. The differences in yield of nanometric particles of each polymorphic form were discussed in accordance to crystallographic form of cellulose. Solvent casting method was applied to produce chitosan films filled with 1, 3, and 5 wt% of nanocrystalline C I and nanocrystalline C II. Mechanical testing proved that the tensile properties of the composites were closely related to the polymorphic variety of nanocrystalline cellulose. On the other hand, SEM microphotographs of the produced composites confirmed that good distribution of nanoparticles in the chitosan matrix was crucial for obtaining materials with enhanced mechanical properties. Filling the chitosan matrix with 1 wt% of nanocrystalline C I was determined to be the most effective. POLYM. COMPOS., 39:E448–E456, 2018. © 2017 Society of Plastics Engineers
Stoichiometric δ‐NbN: The Most Incompressible Cubic Transition Metal Mononitride
Authors: Tan Jiao , Zhang Shihao , Wang Shanmin , Wang Wendan , Zheng Xu , Zhao Jianfa , Li Wenmin , Mao Xiaochun , Liu Ke , Zhou Xiaolin , Zhao Yusheng , Jin Changqing , Yu Xiaohui
Published: August 2017

We report the high‐pressure synthesis and elastic properties of stoichiometric cubic δ‐NbN investigated by a combination of experiments and first principles calculations. Using the high pressure solid‐state ion‐exchange reaction route, we have successfully synthesized polycrystalline δ‐NbN at 5.5 GPa and 1673 K. The refined lattice parameter of as‐synthesized sample is 4.3960(6) Å, corresponding to the stoichiometric niobium nitride. The determined bulk modulus of δ‐NbN is B0 = 319(2) GPa with  = 4.4(2), which is one of the most incompressible cubic transition metal mononitrides. Theoretical calculations of the elastic constants, bulk modulus, shear modulus, Young's modulus, and Poisson's ratio agree well with experimental and previous theoretical results. The calculated minimum shear strength of δ‐NbN is 23.4 GPa for the (111) slip system, comparable to those of ZrN and HfN. In addition, a finite density of states at the Fermi level was revealed for δ‐NbN, hence exhibiting metallic behavior.
N‐Butyl‐4‐hydroxy‐1,8‐naphthalimide: A new matrix for small molecule analysis by matrix‐assisted laser desorption/ionization mass spectrometry
Authors: Cheng Xina , Ye Xueting , Liu Dan , Zhao Nan , Gao Huiyuan , Wang Ping , Ge Guangbo , Zhang Xiaozhe
Published: August 2017

Rationale

The matrix plays an essential role in defining detection limits and ionization yields of analytes in matrix‐assisted laser desorption/ionization mass spectrometry (MALDI‐MS) analysis. Small molecule MALDI‐MS analyses commonly suffer from the high background interference generated from matrices. Moreover, the inhomogeneous crystallization of some matrices, such as 2,5‐dihydroxybenzoic acid (DHB), is to the detriment of the quality or repeatability of detection. We have found that N‐butyl‐4‐hydroxy‐1,8‐naphthalimide (BHN) can provide improved performance as a matrix for small molecule analysis.

Methods

BHN was evaluated in the low‐mass region for its ionization efficiency, repeatability and background interference using O‐acetyl‐L‐carnitine hydrochloride, Aβ35‐40, Aβ35‐42, and oxytocin as the model analytes. In addition, the modification effects of BHN on DHB were investigated for the in situ analysis of endogenous compounds in rat brain slices using Fourier transform ion cyclotron resonance (FTICR)‐MS.

Results

BHN is capable of ionizing small molecules, including O‐acetyl‐L‐carnitine hydrochloride and peptides, with high repeatability and low background interference signals. A low concentration of BHN (3 mM) modifies the crystallization state of DHB but still retains its ionization performance. The determination of small molecules desorbed from tissue slices was significantly improved by using a binary matrix of DHB and BHN, yielding superior signal‐to‐noise ratio and signal intensities.

Conclusions

The new matrix BHN has exhibited suitability for the analysis of small molecules. Compared with the conventional matrices, CHCA and DHB, BHN provides a clean background in the low‐mass region. In combination with DHB, the ability of BHN to form highly homogenous crystalline particles shows the clear beneficial effects of BHN for the reproducibility of MS detection.
Stability‐indicating assay method for acotiamide: Separation, identification and characterization of its hydroxylated and hydrolytic degradation products along with a process‐related impurity by ultra‐high‐performance liquid chromatography/electrospray ionization quadrupole time‐of‐flight tandem mass spectrometry
Authors: Thummar Mohit , Patel Prinesh N. , Samanthula Gananadhamu , Ragampeta Srinivas
Published: August 2017

Rationale

The presence of impurities and degradation products will affect the pharmacokinetic, pharmacodynamic properties and alter the safety of a drug. Hence, the development of a stability‐indicating assay method is an integral part of quality product development and is crucial for the regulatory approval of drug products.

Methods

Acotiamide was subjected to stress degradation under hydrolytic, oxidative, photo and thermal stress conditions. The resulted degradation products (DPs), as well as a process‐related impurity (IMP), were selectively separated from the drug on a Waters Acquity HSS cyano column (100 × 2.1 mm, 1.8 μm) with a mobile phase containing a gradient mixture of 0.1% formic acid and acetonitrile (ACN) at a flow rate of 0.25 mL min−1.

Results

The drug was found to degrade under hydrolytic (acidic and basic), oxidative and photolytic stress while it remained stable under neutral hydrolytic and thermal stress conditions. The seven degradation products (DPs) and one process‐related impurity (IMP) were observed. All the DPs and process‐related IMP were well separated by the developed ultra‐high‐performance liquid chromatography (UHPLC) method and subsequently characterized by UHPLC/electrospray ionization quadrupole time‐of‐flight tandem mass spectrometry (ESI‐QTOF‐MS/MS). The proposed UHPLC method was validated with respect to specificity, linearity, accuracy, precision and robustness as per ICH guideline, Q2 (R1).

Conclusions

All the observed DPs were new and formed by hydrolysis of an amide bond, phenyl ring hydroxylation and hydrolysis of the methoxy group of the phenyl ring. The despropyl process‐related impurity was observed and well separated from the drug. The proposed UHPLC mass spectrometric method has greater utility in the identification of DPs in much less time with excellent selectivity.
Puppy or service dog in training? Why it matters
Authors: Masinter Michael R.
Published: August 2017

Several schools have reported the appearance on campus of students with puppies who claim the puppies are service dogs in training. This column discusses how to respond.
Take proactive approach to academic misconduct
Authors: McCarthy Claudine
Published: August 2017

Between the high turnover among faculty members, the disconnect between student affairs and faculty, and the common misconceptions about plagiarism by students, academic integrity could easily fall between the cracks in today's higher ed environment. But student affairs professionals can play a critical role in bridging the gap between students and faculty to raise awareness about the importance of AI as well as how to prevent and address academic misconduct.
Concise Review: Mesenchymal Stem Cells in Cardiovascular Regeneration: Emerging Research Directions and Clinical Applications
Authors: Majka Marcin , Sułkowski Maciej , Badyra Bogna , Musiałek Piotr
Published: August 2017

Experimental and early clinical data suggest that, due to several unique properties, mesenchymal stem cells (MSCs) may be more effective than other cell types for diseases that are difficult to treat or untreatable. Owing to their ease of isolation and culture as well as their secretory and immunomodulatory abilities, MSCs are the most promising option in the field of cell-based therapies. Although MSCs from various sources share several common characteristics, they also exhibit several important differences. These variations may reflect, in part, specific regional properties of the niches from which the cells originate. Moreover, morphological and functional features of MSCs are susceptible to variations across isolation protocols and cell culture conditions. These observations suggest that careful preparation of manufacturing protocols will be necessary for the most efficient use of MSCs in future clinical trials. A typical human myocardial infarct involves the loss of approximately 1 billion cardiomyocytes and 2–3 billion other (mostly endothelial) myocardial cells, leading (despite maximized medical therapy) to a significant negative impact on the length and quality of life. Despite more than a decade of intensive research, search for the “best” (safe and maximally effective) cell type to drive myocardial regeneration continues. In this review, we summarize information about the most important features of MSCs and recent discoveries in the field of MSCs research, and describe current data from preclinical and early clinical studies on the use of MSCs in cardiovascular regeneration.
Influence of the preparation conditions ofPd‐ZrO2andAuPd‐ZrO2nanoparticle–decorated functionalisedMWCNTs: Electron spectroscopy study aided with theQUASES
Authors: Lesiak B. , Zemek J. , Jiricek P. , Malolepszy A. , Stobinski L.
Published: August 2017

The Pd, AuPd, and ZrO2nanoparticle–decorated functionalised multiwalled carbon nanotubes (f‐MWCNTs) were reported as efficient catalysts of formic acid (FA) electro‐oxidation. Different preparation conditions influence their chemical and structural properties analysed by X‐ray photoelectron spectroscopy aided with the quantitative analysis of surfaces by electron spectroscopy. Different reduction procedures such as NaBH4, a polyol microwave‐assisted method (PMWA), and a high pressure microwave reactor (HPMWR) were applied for decorating ZrO2/f‐MWCNTs with Pd and AuPd nanoparticles. The ZrO2nanoparticles are attached through oxygen groups to the surface of f‐MWCNTs. In NaBH4and HPMWR procedures, Pd nanoparticles precipitate predominantly on ZrO2of nearly nominal stoichiometry, whereas in PMWA procedure, Pd and AuPd nanoparticles precipitate predominantly on the surface of f‐MWCNTs, bridging with oxygen groups and ZrOx(x < 2) and leading to Pd‐O‐Zr phase formation. Strong reducing procedures (NaBH4and FA) led to smaller Pd nanoparticle size, Pd oxide content, and PdOxoverlayer thickness in contrary to weak reduction procedures (HPMWR and PMWA). The highest content of Pd‐O‐Zr phase appeared for Pd predominant precipitation on ZrO2nanoparticles (HPMWR) in contrary to Pd and AuPd predominant precipitation on surface of f‐MWCNTs (NaBH4 ~ FA > PMWA). Larger content of Pd‐O‐Zr phase in AuPd‐decorated ZrO2/f‐MWCNTs in contrary to Pd‐decorated sample (PMWA) could be justified by different electronic properties of nanoparticles. The FA treatment of Pd and AuPd‐ZrO2/f‐MWCNTs samples provided decreasing Pd oxide content, overlayer thickness, nanoparticle size, increasing nanoparticle surface coverage and density, amount of Pd‐O‐Zr, what results from reduction of oxygen groups bridging with Pd and ZrOxnanoparticles, also through Pd‐O‐Zr phase.
Dual‐numbered Hopfield neural networks
Authors: Kobayashi Masaki
Published: August 2017

In recent years, Hopfield neural networks using Clifford algebra have been studied. Clifford algebra is also referred to as geometric algebra, and is useful to deal with geometric objects. There are three kinds of Clifford algebra with degree 2; complex, hyperbolic, and dual‐numbered. Complex‐valued Hopfield neural networks have been studied by many researchers. Several models of hyperbolic Hopfield neural networks have also been proposed. It has been difficult to construct dual‐numbered Hopfield neural networks. In this work, we propose dual‐numbered Hopfield neural networks by modification of hyperbolic Hopfield neural networks with the split activation function. The stability condition and Hebbian learning rule are also provided. © 2017 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.
Damping control method utilizing overvoltage resistor under light load condition
Authors: Wijaya Febry Pandu , Kobayashi Hiroyasu , Kondo Keiichiro , Iwasaki Tetsuya , Tsumura Akihiro
Published: August 2017

High feedback gain of the light‐load regenerative brake control increases the regenerative brake power. However, if the regenerating load changes suddenly, higher gain causes more rapid change of the motor current. And because of the delay in the motor control, it increases the filter capacitor (FC) voltage and may activate the overvoltage protection. This letter proposes a damping control method to reduce the spike of the FC voltage utilizing the overvoltage resistor. The proposed method is verified by numerical simulation assuming an actual railway vehicle under the condition of load shutdown. By means of this method, the overvoltage resistor can be effectively utilized to reduce the FC voltage spike, which results in saving the substation energy. © 2017 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.
Actein alleviates 2,3,7,8‐tetrachlorodibenzo‐p‐dioxin‐mediated cellular dysfunction in osteoblastic MC3T3‐E1 cells
Authors: Choi Eun Mi , Suh Kwang Sik , Jung Woon‐Won , Park So Young , Chin Sang Ouk , Rhee Sang Youl , Pak Youngmi Kim , Chon Suk
Published: August 2017

The environmental pollutant 2,3,7,8‐tetrachlorodibenzo‐p‐dioxin (TCDD) is known to affect bone metabolism. We evaluated the protective effects of the triterpene glycoside actein from the herb black cohosh against TCDD‐induced toxicity in MC3T3‐E1 osteoblastic cells. We found that TCDD significantly reduced cell viability and increased apoptosis and autophagy in MC3T3‐E1 osteoblastic cells (P < .05). In addition, TCDD treatment resulted in a significant increase in intracellular calcium concentration, mitochondrial membrane potential collapse, reactive oxygen species (ROS) production, and cardiolipin peroxidation, whereas pretreatment with actein significantly mitigated these effects (P < .05). The effects of TCDD on extracellular signal‐related kinase (ERK), aryl hydrocarbon receptor, aryl hydrocarbon receptor repressor, and cytochrome P450 1A1 levels in MC3T3‐E1 cells were significantly inhibited by actein. The levels of superoxide dismutase, ERK1, and nuclear factor kappa B mRNA were also effectively restored by pretreatment with actein. Furthermore, actein treatment resulted in a significant increase in alkaline phosphatase (ALP) activity and collagen content, as well as in the expression of genes associated with osteoblastic differentiation (ALP, type I collagen, osteoprotegerin, bone sialoprotein, and osterix). This study demonstrates the underlying molecular mechanisms of cytoprotection exerted by actein against TCDD‐induced oxidative stress and osteoblast damage.
RNA on the brain: emerging layers of post‐transcriptional regulation in cerebral cortex development
Authors: Lennox Ashley L. , Mao Hanqian , Silver Debra L.
Published: August 2017

Embryonic development is a critical period during which neurons of the brain are generated and organized. In the developing cerebral cortex, this requires complex processes of neural progenitor proliferation, neuronal differentiation, and migration. Each step relies upon highly regulated control of gene expression. In particular, RNA splicing, stability, localization, and translation have emerged as key post‐transcriptional regulatory nodes of mouse corticogenesis. Trans‐regulators of RNA metabolism, including microRNAs (miRs) and RNA‐binding proteins (RBPs), orchestrate diverse steps of cortical development. These trans‐factors function either individually or cooperatively to influence RNAs, often of similar classes, termed RNA regulons. New technological advances raise the potential for an increasingly sophisticated understanding of post‐transcriptional control in the developing neocortex. Many RNA‐binding factors are also implicated in neurodevelopmental diseases of the cortex. Therefore, elucidating how RBPs and miRs converge to influence mRNA expression in progenitors and neurons will give valuable insights into mechanisms of cortical development and disease. WIREs Dev Biol 2018, 7:e290. doi: 10.1002/wdev.290

This article is categorized under:

Gene Expression and Transcriptional Hierarchies > Regulatory RNA

Nervous System Development > Vertebrates: Regional Development

Adult Stem Cells, Tissue Renewal, and Regeneration > Stem Cells and Disease
Student Organizations as Avenues for Leader Learning and Development
Authors: Sessa Valerie I. , Alonso Nicole , Farago Pamela , Schettino Gaynell , Tacchi Kelcie , Bragger Jennifer D.
Published: August 2017

This chapter describes theory and research demonstrating that the experiences students have within student organizations, and the people with whom they interact within those organizations, are powerful triggers for leader learning and development.
Mindful eating and its relationship with body mass index, binge eating,anxiety and negative affect
Authors: Pintado-Cucarella Sheila , Rodríguez-Salgado Paulina
Published: August 2017

Mindful eating concerns an awareness of our dietary habits, while its absence is typically associated with anxiety, negative affect and bingeeating. The objective of this study was to analyze these variables in a sample of 216 individuals, divided in four groups: students who practicedsport regularly, university athletes, yoga practitioners and persons suffering from obesity. They were assessed by a semi-structured interview andthe questionnaires MEQ, BES, PANAS and BAI. Statistical analyses included descriptive statistics, Pearson correlation, ANOVA and multipleregression. Results demonstrated that people who have less awareness of their eating habits are generally more overweight, more anxious and havehigher levels of negative affect, while they demonstrate less control over their eating habits. Moreover, these variables can predict binge eating.The model obtained was significant (p < .001) and its predictive capacity through R square corrected was .51. This means that the model predictsa 51% of binge eating from mindful eating, body mass index, anxiety and negative affect.
Designing boats for the Volvo Ocean Race: An ongoing process of optimization and finding the right compromise
Authors: Mathijsen Django
Published: August 2017

Every three years, the best sailors in the world compete in the Volvo Ocean Race. For decades now, these sailing yachts have been sporting carbon fiber reinforced epoxy hulls. It was one of the first industries to adopt these materials. Reinforced Plastics talks to two of the people involved in designing these racers (Chris Cochran of Farr Yacht Design, and Guillaume Verdier) and finds out how it is done.
EXPLORING NEW CAHOKIAN NEIGHBORHOODS: STRUCTURE DENSITY ESTIMATES FROM THE SPRING LAKE TRACT, CAHOKIA
Authors: Baires Sarah E. , Baltus Melissa R. , Malouchos Elizabeth Watts
Published: August 2017

We present the recent results of a magnetometry survey of the Spring Lake Tract conducted during the summer of 2015 at Cahokia Mounds State Historic Site located along the Mississippi River Floodplain in southern Illinois. This tract, located southeast of Woodhenge and west of the Grand Plaza, is situated north of two known borrow pits and includes an additional, previously unidentified borrow pit. Through comparing our gradiometer results with our subsequent test excavations, we argue that this area of Cahokia potentially demonstrates an increase in building density at the Spring Lake Tract during the transition between the Terminal Late Woodland and Lohmann phases. In addition, our survey and exaction results demonstrate that this area was densely occupied between the Lohmann and Stirling phases. During the Moorehead phase, we identify a possible increase in habitation based on hypothesized structure density using statistical analyses of length and width ratios (m) and structure area (m2). Our preliminary results suggest that the Spring Lake Tract saw an increase in habitation during the Moorehead phase, a new perspective on the density and use of domestic space during Cahokia's late occupational history.
The Effect of Participating in a Surgical Site Infection (SSI) Surveillance Network on the Time Trend of SSI Rates: A Systematic Review
Authors: Abbas Mohamed , Tartari Ermira , Allegranzi Benedetta , Pittet Didier , Harbarth Stephan
Published: August 2017

This systematic literature review reveals that participating in a surgical site infection (SSI) surveillance network is associated with short-term reductions in SSI rates: relative risk [RR] for year 2, 0.80 (95% confidence interval [CI], 0.79–0.82); year 3 RR, 0.92 (95% CI, 0.90–0.94); year 4 RR, 0.98 (95% CI, 0.96–1.00).

Infect Control Hosp Epidemiol 2017;38:1364–1366
Beta-plane turbulence above monoscale topography
Authors: Constantinou Navid C. , Young William R.
Published: August 2017

Using a one-layer quasi-geostrophic model, we study the effect of random monoscale topography on forced beta-plane turbulence. The forcing is a uniform steady wind stress that produces both a uniform large-scale zonal flow $U(t)$ and smaller-scale macroturbulence characterized by standing and transient eddies. The large-scale flow $U$ is retarded by a combination of Ekman drag and the domain-averaged topographic form stress produced by the eddies. The topographic form stress typically balances most of the applied wind stress, while the Ekman drag provides all of the energy dissipation required to balance the wind work. A collection of statistically equilibrated numerical solutions delineate the main flow regimes and the dependence of the time average of $U$ on parameters such as the planetary potential vorticity (PV) gradient $\unicode[STIX]{x1D6FD}$ and the statistical properties of the topography. We obtain asymptotic scaling laws for the strength of the large-scale flow $U$ in the limiting cases of weak and strong forcing. If $\unicode[STIX]{x1D6FD}$ is significantly smaller than the topographic PV gradient, the flow consists of stagnant pools attached to pockets of closed geostrophic contours. The stagnant dead zones are bordered by jets and the flow through the domain is concentrated into a narrow channel of open geostrophic contours. In most of the domain, the flow is weak and thus the large-scale flow $U$ is an unoccupied mean. If $\unicode[STIX]{x1D6FD}$ is comparable to, or larger than, the topographic PV gradient, then all geostrophic contours are open and the flow is uniformly distributed throughout the domain. In this open-contour case, there is an ‘eddy saturation’ regime in which $U$ is insensitive to large changes in the wind stress. We show that eddy saturation requires strong transient eddies that act effectively as PV diffusion. This PV diffusion does not alter the kinetic energy of the standing eddies, but it does increase the topographic form stress by enhancing the correlation between the topographic slope and the standing-eddy pressure field. Using bounds based on the energy and enstrophy power integrals, we show that as the strength of the wind stress increases, the flow transitions from a regime in which the form stress balances most of the wind stress to a regime in which the form stress is very small and large transport ensues.
Substantial drag reduction in turbulent flow using liquid-infused surfaces
Authors: Van Buren Tyler , Smits Alexander J.
Published: August 2017

Experiments are presented that demonstrate how liquid-infused surfaces can reduce turbulent drag significantly in Taylor–Couette flow. The test liquid was water, and the test surface was composed of square microscopic grooves measuring $100~\unicode[STIX]{x03BC}\text{m}$ to $800~\unicode[STIX]{x03BC}\text{m}$, filled with alkane liquids with viscosities from 0.3 to 1.4 times that of water. We achieve drag reduction exceeding 35 %, four times higher than previously reported for liquid-infused surfaces in turbulent flow. The level of drag reduction increased with viscosity ratio, groove width, fluid area fraction and Reynolds number. The optimum groove width was given by $w^{+}\approx 35$.