bluuebunny/crossref_metadata_2025 huggingface dataset:
Periaqueductal gray activates antipredatory neural responses in the amygdala of foraging rats
Authors: Kim Eun Joo , Kong Mi-Seon , Park Sanggeon , Cho Jeiwon , Kim Jeansok J
Published: August 2024

Pavlovian fear conditioning research suggests that the interaction between the dorsal periaqueductal gray (dPAG) and basolateral amygdala (BLA) acts as a prediction error mechanism in the formation of associative fear memories. However, their roles in responding to naturalistic predatory threats, characterized by less explicit cues and the absence of reiterative trial-and-error learning events, remain unexplored. In this study, we conducted single-unit recordings in rats during an ‘approach food-avoid predator’ task, focusing on the responsiveness of dPAG and BLA neurons to a rapidly approaching robot predator. Optogenetic stimulation of the dPAG triggered fleeing behaviors and increased BLA activity in naive rats. Notably, BLA neurons activated by dPAG stimulation displayed immediate responses to the robot, demonstrating heightened synchronous activity compared to BLA neurons that did not respond to dPAG stimulation. Additionally, the use of anterograde and retrograde tracer injections into the dPAG and BLA, respectively, coupled with c-Fos activation in response to predatory threats, indicates that the midline thalamus may play an intermediary role in innate antipredatory defensive functioning.
Polysaccharides induce deep-sea Lentisphaerae strains to release chronic bacteriophages
Authors: Wang Chong , Zheng Rikuan , Zhang Tianhang , Sun Chaomin
Published: August 2024

Viruses are ubiquitous in nature and play key roles in various ecosystems. Notably, some viruses (e.g. bacteriophage) exhibit alternative life cycles, such as chronic infections without cell lysis. However, the impact of chronic infections and their interactions with the host organisms remains largely unknown. Here, we found for the first time that polysaccharides induced the production of multiple temperate phages infecting two deep-sea
Lentisphaerae
strains (WC36 and zth2). Through physiological assays, genomic analysis, and transcriptomics assays, we found these bacteriophages were released via a chronic style without host cell lysis, which might reprogram host polysaccharide metabolism through the potential auxiliary metabolic genes (AMGs). The findings presented here, together with recent discoveries made on the reprogramming of host energy-generating metabolisms by chronic bacteriophages, shed light on the poorly explored marine virus-host interaction and bring us closer to understanding the potential role of chronic viruses in marine ecosystems.
DNA replication errors are a major source of adaptive gene amplification
Authors: Chuong Julie N , Nun Nadav Ben , Suresh Ina , Matthews Julia , De Titir , Avecilla Grace , Abdul-Rahman Farah , Brandt Nathan , Ram Yoav , Gresham David
Published: August 2024

Detecting and understanding heritable changes in DNA that contribute to adaptive evolution is a primary goal of evolutionary biology. Copy number variants (CNVs)—gains and losses of genomic sequences—are an important source of genetic variation underlying rapid adaptation and genome evolution. However, despite their central role in evolution little is known about the factors that contribute to the structure, size, formation rate, and fitness effects of adaptive CNVs. Local genome elements are likely to be an important determinant of these properties. Whereas it is known that point mutation rates vary with genomic location and local sequence features, the role of genome architecture in the formation, selection, and the resulting evolutionary dynamics of CNVs is poorly understood. Previously, we have found that the
GAP1
gene in
Saccharomyces cerevisiae
undergoes frequent and repeated amplification and selection under long-term experimental evolution in glutamine-limiting conditions. The
GAP1
gene has a unique genomic architecture consisting of two flanking long terminal repeats (LTRs) and a proximate origin of DNA replication (autonomously replicating sequence, ARS), which are likely to promote rapid
GAP1
CNV formation. To test the role of these genomic elements on CNV-mediated adaptive evolution we performed experimental evolution in glutamine-limited chemostats using engineered strains lacking either the adjacent LTRs, ARS, or all elements. Using a CNV reporter system and neural network simulation-based inference (nnSBI) we quantified the formation rate and fitness effect of CNVs for each strain. We find that although
GAP1
CNVs repeatedly form and sweep to high frequency in all strains, removal of local DNA elements significantly impacts the rate and fitness effect of CNVs and the rate of adaptation. We performed genome sequence analysis to define the molecular mechanisms of CNV formation for 177 CNV lineages. We find that 49% of all
GAP1
CNVs are mediated by the DNA replication-based mechanism Origin Dependent Inverted Repeat Amplification (ODIRA) regardless of background strain. In the absence of the local ARS, a distal ARS can mediate ODIRA CNV formation. In the absence of local LTRs homologous recombination mechanisms still mediate gene amplification following
de novo
insertion of retrotransposon elements at the locus. Our study demonstrates the remarkable plasticity of the genome and reveals that DNA replication errors are a predominant source of adaptive CNVs.
Volumen 28, número1
Authors: Cuhso Revista
Published: August 2024

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Effect of Two Regimens of Rectal Diclofenac on Post Adenotonsillectomy Pain in Children
Authors: Iwuoha Chinedu Paul , Aggo Alfred Tamunoigbanibo , Johnson Uyoata Udo
Published: August 2024

Aim: To determine the post adenotonsillectomy analgesic effect of single versus divided dose regimen of rectal diclofenac in children.
Study Design: Prospective, randomized, double blind, comparative study.
Place and Duration of Study: University of Port Harcourt Teaching Hospital (UPTH), Port Harcourt, Nigeria, from June to November, 2023.
Methodology: Following ethical approval (Ethical reference UPTH/ADM/90/S.II/VOL.XI/1285, granted 25th November, 2021) and parental consent, 50 children, of American Society of Anesthesiologists (ASA) class I and II, aged 1 – 6 years, were randomized into groups I and II, of 25 each. All children had intratracheal general anaesthesia induced with propofol, followed by atracurium, fentanyl, and maintained by isoflurane in 100% Oxygen. Group I received suppository diclofenac 2 - 3mg/kg rectally, in two divided doses 12 hours apart (first dose at induction), while group II received suppository diclofenac 2 - 3mg/kg rectally, as single dose (at induction). Pain was assessed using the Face, Leg, Arm, Cry, Consolability (FLACC) scale. The time to first analgesic request, (TTFAR) was defined as the period from rectal drug administration to pain score of ≥ 4. Analgesic was given when FLACC score was ≥ 4.
Results: All 50 subjects completed the study. The mean TTFAR (hours) was significantly more prolonged (7.82±1.18) in group I compared to 5.42±1.19 observed in group II, P = 0.0081, with significantly greater 24-hour analgesic consumption in group II, P = 0.0044, and 0.0003.
Conclusion: Suppository diclofenac administered rectally in two divided doses achieved significantly more prolonged postoperative analgesia compared to single equivalent dose.
Mechanization in Sericulture: An Overview
Authors: Marak Merrylina , Singha Th. Aruna , Saikia Dipankar
Published: August 2024

Sericulture is a labour-intensive enterprise involving activities with dependency on manual labour. With the growing competition of Chinese silk which is of superior quality and lesser price, the indigenous silk is falling in demand in the domestic market. There is a felt need to reduce the cost of production to improve the quality of Indian silk and its value. This can be achieved through mechanization in the various steps involved. For instance Tractor-operated mouldboards or disk plough and Tractor-operated Auger Digger for raising of plantations reduce labour cost to a considerable extent. Power-operated Sprayers for disinfection of rearing houses increases efficiency and also ensures good harvest of crop. Mechanisation of post cocoon sector for cocoon stifling, cocoon cutting and for silk reeling and spinning have improved quality, increased productivity thus reduction in prices. Mechanization will not only reduce drudgery and dependency on labour but also enhance the quality of life. Mechanisation thus culminates to lessening the cost of production.
Impact of Integrated Nutrient Management Practices on Chemical Properties of Soil under Finger Millet Cultivation in Assam, India
Authors: Boruah Anasuya , Saikia Mrinal , Sarma Hridesh Harsha , N Kamal , Kumar Mayank
Published: August 2024

A field experiment was carried out during the rabi season of 2022-2023 at Instructional-cum-Research Farm, Assam Agricultural University, Jorhat to evaluate the performance of different integrated nutrient management practices on chemical properties of soil under finger millet cultivation in rainfed upland condition. The design of the experiment was randomized block design (RBD) with three replications. Individual plot size was 4 m × 3 m. Total of 9 treatments were taken under consideration. The finger millet variety used for the experiment was AAU-GSG-Marua Dhan 1. Results revealed that available nitrogen in soil after harvest was found to be significantly higher under treatment T3 (255.1 kg ha-1) followed by T4 (250.9 kg ha-1). In case of phosphorus, available P2O5 in soil after harvest was found to be significantly higher under treatment T3 (28.53 kg ha-1) followed by T4 (27.02 kg ha-1) and T2 (25.16 kg ha-1). For potassium, available K2O in soil after harvest was found to be significantly higher in T3 (243.1 kg ha-1) followed by (240.6 kg ha-1) and T2 (238.6 kg ha-1). The lowest values for available N, P2O5 and K2O in soil after harvest were observed in the control treatment.
Determination of Polyphenols, Reducing Potential and FT-IR Analysis of Green Tea (Camellia sinensis L.) Leaves Extract for Nanoparticles Synthesis
Authors: Bisht Komal , Pandey Niharika , Gautam Sneh , Lohani Pushpa
Published: August 2024

Green Tea (Camellia sinensis L.) is renowned for its therapeutic properties due to its phenolic compounds. Extracts from plants with high polyphenol content possess antioxidant properties that neutralize free radicals involved in the oxidation of various molecules. This study investigated the total phenolic and flavonoid content, 1,1-diphenylpicrylhydrazyl (DPPH) radical scavenging activity (RSA), and ferric reducing antioxidant power (FRAP) of commercially available green tea leaves for potential use in the green synthesis of silica nanoparticles. The antioxidant activity of green tea leaves demonstrates its reducing power, which is crucial for utilizing its extract in nanoparticle synthesis. Gallic acid and quercetin served as standards in the Folin–Ciocalteu and aluminum chloride methods, respectively, to measure total phenolic and flavonoid concentrations. To determine antioxidant content ascorbic acid and gallic acid were standards for the DPPH free radical scavenging and FRAP assays. Fourier Transform Infrared (FT-IR) spectra was performed to evaluate the green tea extract. The results revealed green tea leaves exhibited high phenolic, flavonoid content and significant antioxidant activity. The presence of few notable vibrational bands in FT-IR graph also confirmed the existence of chemical substances that are associated with antioxidant qualities (polyphenols, flavonoids).  Indicating that the green tea leaf extract can act as an effective reducing and capping agent in the synthesis of silica nanoparticles.
A review of the impact of sensory processing sensitivity on mental health in university students
Authors: Mac Allison , Kim Myo-Kyoung , Sevak Rajkumar J.
Published: August 2024

Introduction

The concept of sensory processing sensitivity (SPS) was first introduced by Aron and Aron (1996) as an innate trait characterized by heightened processing of sensory, emotional, and physical stimuli. Since the concept’s introduction in 1996, high SPS has been shown to be associated with poor physical and mental health. It is possible that this is especially true in university students, who are frequently faced with numerous stressors, such as intense workloads and test anxiety.

Methods

This article is a systematic literature review conducted through EBSCOHost using the following databases: Academic Search Complete, APA PsycArticles, APA PsycInfo, Education Research Complete, ERIC, MEDLINE Complete, and SocINDEX. Search terms included terms regarding high sensory processing sensitivity, university or professional students, and mental health.

Results

A total of 6 studies were included. University students with high SPS experienced heightened reactions to sensory, emotional, and physical stimuli. The studies demonstrate correlations of high SPS with outcomes such as depressive tendencies and difficulty adjusting to college.

Discussion

These findings highlight that SPS is associated with poor mental health outcomes. The results underscore the importance of developing support methods for students with high SPS. Future studies should further explore SPS in university students to develop targeted support methods and programs.
Sustainability as Environmental Framework May Be Outdated, Lawyers Argue
Authors: Showstack Randy
Published: July 2014

Goals based on sustainability “are no longer the best framework” for thinking about environmental law, governance systems, and socioecological dynamics in a world that is rapidly changing due to climate change and other forces. That is according to Melinda Harm Benson, assistant professor in the Department of Geography and Environmental Studies at the University of New Mexico, who challenged the long‐held concept of environmental sustainability at an 8 July discussion entitled “The End of Sustainability?” sponsored by the Environmental Law Institute.
Bitz, Ginoux, Jacobson, Nizkorodov, and Yang Receive 2013 Atmospheric Sciences Ascent Awards: Citation for Sergey Nizkorodov
Authors: Webster Peter J.
Published: July 2014

The Atmospheric Sciences section of AGU awards one of the five Ascent Awards to Professor Sergey Nizkorodov of the Department of Chemistry at the University of California, Irvine (UCI) for elucidating at the molecular level the formation, growth, and reactions of organic molecules in the atmosphere.
Bitz, Ginoux, Jacobson, Nizkorodov, and Yang Receive 2013 Atmospheric Sciences Ascent Awards: Response
Authors: Yang Ping
Published: July 2014

I am honored and humbled that the AGU Atmospheric Sciences section decided to select me as one of the five recipients of the 2013 Ascent Award and would like to thank the selection committee for this recognition.
Clockwise rotation of the Brahmaputra Valley relative to India: Tectonic convergence in the eastern Himalaya, Naga Hills, and Shillong Plateau
Authors: Vernant P. , Bilham R. , Szeliga W. , Drupka D. , Kalita S. , Bhattacharyya A. K. , Gaur V. K. , Pelgay P. , Cattin R. , Berthet T.
Published: July 2014

GPS data reveal that the Brahmaputra Valley has broken from the Indian Plate and rotates clockwise relative to India about a point a few hundred kilometers west of the Shillong Plateau. The GPS velocity vectors define two distinct blocks separated by the Kopili fault upon which 2–3 mm/yr of dextral slip is observed: the Shillong block between longitudes 89 and 93°E rotating clockwise at 1.15°/Myr and the Assam block from 93.5°E to 97°E rotating at ≈1.13°/Myr. These two blocks are more than 120 km wide in a north‐south sense, but they extend locally a similar distance beneath the Himalaya and Tibet. A result of these rotations is that convergence across the Himalaya east of Sikkim decreases in velocity eastward from 18 to ≈12 mm/yr and convergence between the Shillong Plateau and Bangladesh across the Dauki fault increases from 3 mm/yr in the west to >8 mm/yr in the east. This fast convergence rate is inconsistent with inferred geological uplift rates on the plateau (if a 45°N dip is assumed for the Dauki fault) unless clockwise rotation of the Shillong block has increased substantially in the past 4–8 Myr. Such acceleration is consistent with the reported recent slowing in the convergence rate across the Bhutan Himalaya. The current slip potential near Bhutan, based on present‐day convergence rates and assuming no great earthquake since 1713 A.D., is now ~5.4 m, similar to the slip reported from alluvial terraces that offsets across the Main Himalayan Thrust and sufficient to sustain a Mw ≥ 8.0 earthquake in this area.
A blocking view of the stratosphere‐troposphere coupling
Authors: Davini P. , Cagnazzo C. , Anstey J. A.
Published: July 2014

Dynamical influence from the stratosphere is known to play a role in shaping the wintertime tropospheric circulation patterns. Observations suggest that this influence is strongest following weak and strong polar vortex events, termed sudden stratospheric warmings (SSWs) and vortex intensification (VI) events, respectively. In this work, stratosphere‐troposphere coupling is studied through the modulation by extreme vortex events of the Northern Hemispheric tropospheric blocking frequency and eddy‐driven jet displacements. This is done using three reanalysis data sets and the Centro Euro‐Mediterraneo sui Cambiamenti Climatici Climate Model with a resolved Stratosphere (CMCC‐CMS) coupled model control run. Reanalysis results suggest the existence of distinct patterns of blocking activity following extreme vortex events. Over the Atlantic basin, SSWs are shown to lead by about 20–50 days the occurrence of increased/reduced blocking frequency on the poleward/equatorward side of the Atlantic jet stream. Anomalies of the opposite sense, with poleward reduction and equatorward enhancement of the blocking frequency, occur following VI events. The response over the Pacific sector is less clear. Compared to reanalyses, CMCC‐CMS shows a similar but weaker response, especially over the Atlantic: a possible explanation is identified in the different structure of the polar vortex and weaker wind shear anomalies with respect to reanalysis. We finally highlight that patterns identified following vortex extremes show similarities with the Northern Annular Mode over the Atlantic but not over the Pacific. This suggests that the stratosphere‐troposphere coupling is more a regional than annular feature.
Impact of EOS MLS ozone data on medium‐extended range ensemble weather forecasts
Authors: Cheung J. C. H. , Haigh J. D. , Jackson D. R.
Published: July 2014

As the stratosphere is largely characterized by its ozone abundance, the quality of the ozone field is important for a realistic representation of the stratosphere in weather and climate models. While the stratosphere is directly affected by radiative heating from ozone photodissociation, ozone abundance might also impact the representation of the troposphere since the stratosphere and troposphere are dynamically linked. In this paper, we examine the potential benefits of using ozone data from the Earth Observing System (EOS) Microwave Limb Sounder (MLS) for medium‐extended range tropospheric forecasts in a current numerical weather prediction system. The global component of the Met Office Global and Regional Ensemble Prediction System is used, which is run at a resolution of N216 L85 with 24 ensemble members. We compare two scenarios of 31 day forecasts covering the same period, one with the current operational ozone climatology and the other with a monthly mean zonally averaged ozone field computed from the MLS data set. In the extreme case of the Arctic “ozone hole” of March 2011, our results show a general reduction in stratospheric forecast errors in the tropics and Southern Hemisphere as a result of the improved representation of ozone. However, even in such a scenario, where the MLS ozone field is much superior to that of the control, we find that tropospheric forecast errors in the medium‐extended range are dominated by the spread of ensemble members and no significant reduction in the root‐mean‐square forecast errors.
Carbon‐Doped Boron Nitride Nanosheets with Ferromagnetism above Room Temperature
Authors: Zhao Chong , Xu Zhi , Wang Hao , Wei Jiake , Wang Wenlong , Bai Xuedong , Wang Enge
Published: July 2014

The possibility to induce magnetism in light‐element materials that contain only s and p electrons is of fundamental and practical importance. Here, weak high‐temperature ferromagnetism is observed in carbon‐doped boron nitride (B‐C‐N) nanosheets. The bulk‐quantities of B‐C‐N nanosheets that are free of metallic impurities are prepared through a multi‐step process. These B‐C‐N samples exhibit ferromagnetic hysteresis stable at room temperature and above, with saturation magnetization and coercivity comparable to the previously reported results of defective graphite samples. The ferromagnetic response disappears upon the removal of carbon dopants from the BN lattice, indicating that the observed magnetism originates from substitutional carbon‐doping rather than from extrinsic magnetic impurities. On the basis of first‐principle calculations it is shown that not only substitutional carbon doping in a honeycomb BN lattice favors spontaneous spin polarization and local moment formation, but also that the spin moments can exhibit long‐range magnetic ordering.
Mechanical properties of natural carbon black reinforced polymer composites
Authors: Ojha Shakuntala , Acharya Samir Kumar , Raghavendra Gujjala
Published: July 2014

This article describes the development of new carbon black material from agricultural waste (wood apple shells) by using pyrolysis method at various carbonization temperatures (400, 600, and 800°C) and used as reinforcement in polymer composites. The wood apple shell carbon black (WAS‐CB) particulates are characterized by proximate analysis, energy dispersive spectroscopy (EDS), and scanning electron microscope (SEM). Results showed that due to increases in carbonization temperature the percentage of carbon improved in the carbon black particles. Furthermore, various tests were performed to determine the effect of new carbon black material on the mechanical properties of composite at different filler loading. The results indicated that mechanical properties like tensile strength, tensile modulus, flexural strength, and flexural modulus are improved as the increase in the carbonization temperature and filler loading. The filler‐matrix bonding was analyzed by SEM. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 41211.
Lean forward: Genetic analysis of temperature‐sensitive mutants unfolds the secrets of oligomeric protein complex assembly
Authors: McMurray Michael
Published: July 2014

Multisubunit protein complexes are essential for cellular function. Genetic analysis of essential processes requires special tools, among which temperature‐sensitive (Ts) mutants have historically been crucial. Many researchers assume that the effect of temperature on such mutants is to drive their proteolytic destruction. In fact, degradation‐mediated elimination of mutant proteins likely explains only a fraction of the phenotypes associated with Ts mutants. Here I discuss insights gained from analysis of Ts mutants in oligomeric proteins, with particular focus on the study of septins, GTP‐binding subunits of cytoskeletal filaments whose structures and functions are the subject of current investigation in my and many other labs. I argue that the kinds of unbiased forward genetic approaches that generate Ts mutants provide information that is largely inaccessible to modern reverse genetic methodologies, and will continue to drive our understanding of higher‐order assembly by septins and other oligomeric proteins.

Also watch the Video Abstract.
Total synthesis of a eukaryotic chromosome: Redesigning and SCRaMbLE‐ing yeast
Authors: Jovicevic Dejana , Blount Benjamin A. , Ellis Tom
Published: July 2014

A team of US researchers recently reported the design, assembly and in vivo functionality of a synthetic chromosome III (SynIII) for the yeast Saccharomyces cerevisiae. The synthetic chromosome was assembled bottom‐up from DNA oligomers by teams of students working over several years with researchers as the first part of an international synthetic yeast genome project. Embedded into the sequence of the synthetic chromosome are multiple design changes that include a novel in‐built recombination scheme that can be induced to catalyse intra‐chromosomal rearrangements in a variety of different conditions. This system, along with the other synthetic sequence changes, is intended to aid researchers develop a deeper understanding of how genomes function and find new ways to exploit yeast in future biotechnologies. The landmark of the first synthesised designer eukaryote chromosome, and the power of its massively parallel recombination system, provide new perspectives on the future of synthetic biology and genome research.
Distinctive Potential Behavior at the Oxidized Surface of a Semiconductor Device in a Concentrated Aqueous Salt Solution
Authors: Maekawa Yuki , Shibuta Yasushi , Sakata Toshiya
Published: July 2014

Conventional electric double layer (EDL) models do not necessarily apply to concentrated solutions such as those found in physiological environments. In this study, we investigated the effect of changing the concentration of a concentrated NaCl solution on the EDL structure formed at the SiO2 surface of a semiconductor‐based ion sensor and backed up the study by using a classical molecular dynamics (MD) simulation. The interfacial potential in the concentrated NaCl solution measured by using the ion sensor showed behavior that differed from that in the dilute solution, which was supported by the calculated potential profile based on the MD simulation. The simulated potential behavior at the SiO2/NaCl solution interface depended strongly on the electrical charge distribution caused by the dipole structure of water molecules and the spatial separation of hydrated ions against the surface charge, unlike that in the bulk solution. Characterization of the solid/liquid interface in concentrated solutions is expected to aid the detection of biomolecular recognition events under biological conditions.
Novel Method for the Fabrication of a Charge‐Transfer Complex Crystal by Photoirradiation
Authors: Matsuda Masaki , Nishi Miki , Koga Shoko , Fujishima Mika , Hoshino Norihisa , Akutagawa Tomoyuki , Hasegawa Hiroyuki
Published: July 2014

A novel method for the fabrication of a charge‐transfer complex crystal was developed. Photoirradiation of a solution of TPP[Co(tbp)(CN)2] and TPP[Co(Pc)(CN)2] (tbp=tetrabenzoporphyrin, Pc=phthalocyanine, TPP=tetraphenylphosphonium) gave a molecular conducting crystal of a charge‐transfer complex TPP[Co(tbp)(CN)2]2, which was produced by the process in which the photoexcited electron in tbp was transferred from the LUMO of tbp to that of Pc.
Biocontrolled Formal Inversion or Retention of L‐α‐Amino Acids to Enantiopure (R)‐ or (S)‐Hydroxyacids
Authors: Busto Eduardo , Richter Nina , Grischek Barbara , Kroutil Wolfgang
Published: July 2014

Natural L‐α‐amino acids and L‐norleucine were transformed to the corresponding α‐hydroxy acids by formal biocatalytic inversion or retention of absolute configuration. The one‐pot transformation was achieved by a concurrent oxidation reduction cascade in aqueous media. A representative panel of enantiopure (R)‐ and (S)‐2‐hydroxy acids possessing aliphatic, aromatic and heteroaromatic moieties were isolated in high yield (67–85 %) and enantiopure form (>99 % ee) without requiring chromatographic purification.
Structural and Biochemical Studies of Actin in Complex with Synthetic Macrolide Tail Analogues
Authors: Pereira Jose H. , Petchprayoon Chutima , Hoepker Alexander C. , Moriarty Nigel W. , Fink Sarah J. , Cecere Giuseppe , Paterson Ian , Adams Paul D. , Marriott Gerard
Published: July 2014

The actin filament‐binding and filament‐severing activities of the aplyronine, kabiramide, and reidispongiolide families of marine macrolides are located within the hydrophobic tail region of the molecule. Two synthetic tail analogues of aplyronine C (SF‐01 and GC‐04) are shown to bind to G‐actin with dissociation constants of (285±33) and (132±13) nM, respectively. The crystal structures of actin complexes with GC‐04, SF‐01, and kabiramide C reveal a conserved mode of tail binding within the cleft that forms between subdomains (SD) 1 and 3. Our studies support the view that filament severing is brought about by specific binding of the tail region to the SD1/SD3 cleft on the upper protomer, which displaces loop‐D from the lower protomer on the same half‐filament. With previous studies showing that the GC‐04 analogue can sever actin filaments, it is argued that the shorter complex lifetime of tail analogues with F‐actin would make them more effective at severing filaments compared with plasma gelsolin. Structure‐based analyses are used to suggest more reactive or targetable forms of GC‐04 and SF‐01, which may serve to boost the capacity of the serum actin scavenging system, to generate antibody conjugates against tumor cell antigens, and to decrease sputum viscosity in children with cystic fibrosis.
SBA‐15‐Functionalized 3‐Oxo‐ABNO as Recyclable Catalyst for Aerobic Oxidation of Alcohols under Metal‐Free Conditions
Authors: Karimi Babak , Farhangi Elham , Vali Hojatollah , Vahdati Saleh
Published: July 2014

The nitroxyl radical 3‐oxo‐9‐azabicyclo [3.3.1]nonane‐N‐oxyl (3‐oxo‐ABNO) has been prepared using a simple protocol. This organocatalyst is found to be an efficient catalyst for the aerobic oxidation of a wide variety of alcohols under metal‐free conditions. In addition, the preparation and characterization of a supported version of 3‐oxo‐ABNO on ordered mesoporous silica SBA‐15 (SABNO) is described for the first time. The catalyst has been characterized using several techniques including simultaneous thermal analysis (STA), transmission electron microscopy (TEM), and nitrogen sorption analysis. This catalyst exhibits catalytic performance comparable to its homogeneous analogue and much superior catalytic activity in comparison with (2,2,6,6‐tetramethylpiperidin‐1‐yl)oxy (TEMPO) for the aerobic oxidation of almost the same range of alcohols under identical reaction conditions. It is also found that SABNO can be conveniently recovered and reused at least 12 times without significant effect on its catalytic efficiency.
Vanadium Oxide Compounds: Structure, Properties, and Growth from the Gas Phase
Authors: Bahlawane Naoufal , Lenoble Damien
Published: July 2014

The structure‐driven properties of vanadium oxide have inspired enormous developments in the last decades, especially as a smart material for energy, sensors, and optoelectronics. The large variety of stable and metastable structures of vanadium oxide is discussed, based on the calculated formation energies and a broad overview of their structure‐related properties. The established chemical deposition processes from the gas phase are reviewed with a particular emphasis on the implemented precursors and the obtained vanadium oxide phases. Although a significant fraction of relevant vanadium oxide compounds is achieved by these methods, there are still rewarding challenges related to their controlled elaboration and the investigation of their responsive properties.
Copper(I)‐Catalyzed Decarboxylative Coupling of Propiolic Acids with Secondary Amines and Aldehydes
Authors: Ermolat'ev Denis S. , Feng Huangdi , Song Gonghua , Van der Eycken Erik V.
Published: July 2014

An efficient microwave‐assisted synthesis of tertiary propargylamines has been developed by copper(I)‐catalyzed decarboxylative A3‐coupling reaction of an alkynylcarboxylic acid with a secondary amine and an aldehyde. A wide range of diversely substituted propargylamines could be synthesized in high yields. The optimal reaction conditions are also effective for 3‐alkylpropiolic acids and for terminal propiolic acid.
Gamma glutamyltransferase, alanine aminotransferase and risk of cancer: Systematic review and meta‐analysis
Authors: Kunutsor Setor K. , Apekey Tanefa A. , Van Hemelrijck Mieke , Calori Giliola , Perseghin Gianluca
Published: July 2014

The prospective evidence for the associations of gamma glutamyltransferase (GGT) and alanine aminotransferase (ALT) with risk of cancer in the general population is uncertain. We conducted a systematic review and meta‐analysis of published prospective observational studies evaluating the associations of baseline levels of GGT and ALT with risk of overall (incidence and/or mortality) and site‐specific cancers. Relevant studies were identified in a literature search of MEDLINE, EMBASE, Web of Science, reference lists of relevant studies to April 2014 and email contact with investigators. Study specific relative risks (RRs) were meta‐analyzed using random effects models. Fourteen cohort studies with data on 1.79 million participants and 57,534 cancer outcomes were included. Comparing top versus bottom thirds of baseline circulating GGT levels, pooled RRs (95% confidence intervals) were 1.32 (1.15–1.52) for overall cancer, 1.09 (0.95–1.24) for cancers of the breast and female genital organs, 1.09 (1.02–1.16) for cancers of male genital organs, 1.94 (1.35–2.79) for cancers of digestive organs and 1.33 (0.94–1.89) for cancers of respiratory and intrathoracic organs. For ALT, corresponding RRs for overall cancer were 0.96 (0.94–0.99) and 1.65 (1.52–1.79) in European and Asian populations, respectively. There was an increased risk of cancers of the digestive organs 2.44 (1.23–4.84). The pooled RR for overall cancer per 5 U/L increment in GGT levels was 1.04 (1.03–1.05). Available observational data indicate a positive log‐linear association of GGT levels with overall cancer risk. The positive association was generally evident for site‐specific cancers. There are geographical variations in the association of ALT and overall cancer.
How and Why Do Cluster Size, Charge State, and Ligands Affect the Course of Metal‐Mediated Gas‐Phase Activation of Methane?
Authors: Schwarz Helmut
Published: July 2014

Recent progress in the gas‐phase activation of methane is discussed. We demonstrate that cluster size, charge state, and ligands crucially affect both the reactivity and selectivity of metal‐mediated bond activation processes. We outline the important role that relativistic effects and spin densities play and discuss the paradigm of two‐state reactivity in thermal reactions. State‐of‐the‐art mass‐spectrometry based experiments, in conjunction with electronic structure calculations, permit identification of the elementary steps at a strictly molecular level and thus allow to uncover mechanistic features for four types of reactions: (i) metal‐mediated dehydrogenation of methane, (ii) ligand‐switch processes of the type ML + CH4→ M(CH3) + HL, (iii) hydrogen‐atom abstraction as the crucial step in the oxidative coupling of methane, and (iv) the mechanism of the challenging CH4→CH3OH conversion.
Performance of diffusion distillation column for production of fuel grade ethanol
Authors: Singh Neetu , Prasad Ram
Published: July 2014

BACKGROUND

Diffusion distillation process was used for separation of ethanol–water mixtures of azeotropic composition. Experimental results were compared with a Stefan–Maxwell equations based mathematical model by assuming point behavior of the process.

RESULTS

The performance of a diffusion distillation column for anhydrous ethanol production has been investigated by extending the point behavior to an integral column under process relevant operating conditions. New modeling results are in better agreement with the experimental data than old modeling results. The maximum variation in selectivity is obtained at lowest flow rate (0.05 mol m‐1 s‐1).

CONCLUSIONS

The diffusion distillation column should be operated at the lowest possible feed rate and the highest possible vaporization temperature to minimize the column length requirement for anhydrous ethanol production. The effect of selectivity on enrichment of ethanol is negligible in long diffusion distillation columns and flux to flow ratio is more important for determination of enrichment. © 2014 Society of Chemical Industry
The dominant synoptic‐scale modes of North American monsoon precipitation
Authors: Seastrand Simona , Serra Yolande , Castro Christopher , Ritchie Elizabeth
Published: July 2014

In this study, we explore the mechanisms of synoptic rainfall variability using observations from the Tropical Rainfall Measuring Mission satellite. Although previously shown to have an important impact on North American monsoon rainfall, tropical cyclones are excluded from this analysis, in order to focus on more frequent synoptic disturbances within the region. A rotated empirical orthogonal function (EOF) analysis of North American monsoon rainfall during June to September 2002–2009 suggests that low‐level tropical disturbances contribute to the leading two modes of precipitation variability within this region. These disturbances result in gulf surges or low‐level surges of moisture up the Gulf of California, and provide a key moisture source to facilitate the development of organized convection. In the first mode, the low‐level trough brings precipitation to lower elevations along the western slopes of the Sierra Madre Occidental south of Hermosillo, Mexico and over the southern Baja Peninsula. In the second mode, the low‐level trough interacts with an upper‐level inverted trough enhancing precipitation into the southwestern United States and northwest Mexico. In particular, the upper‐level trough contributes to the easterly to northeasterly shear across the region, favouring mesoscale convective organization and enhanced deep convection over the Sierra Madre Occidental and higher elevations in southeast Arizona. The EOF methodology offers an objective approach for determining the dominant modes of precipitation for the monsoon region useful for identifying past and monitoring future low‐frequency impacts on these modes.
Experience on radar cross section reduction of a warship
Authors: Blanca Inés García‐Tuñón , Rodríguez José Luis , Obelleiro Fernando , Taboada José M. , Núñez José M. , Cortina Daniel
Published: July 2014

The aim of this work is to present a real experience on radar cross section (RCS) reduction using a radar absorbent material (RAM) made of microwire metallic fibers on a patrol ship of the Spanish Navy. The effectiveness of this RAM has been demonstrated, providing a drastic reduction in the number of significant scatterers or hot spots, together with a significant reduction (between 10 and 15 dB) in the global RCS pattern. © 2014 Wiley Periodicals, Inc. Microwave Opt Technol Lett 56:2270–2273, 2014
Single loop phase noise measurement of microwave oscillators
Authors: Magri Vanessa P. R. , Aguiar Odylio D. , Leme Claudia B. M. P. , Mosso Marbey M. , Furtado S. R. , Carvalho Juliana B. , Souza Jorge A. M.
Published: July 2014

This work describes a simplified procedure to measure ultralow phase‐noise in microwave oscillators using the delay properties of high quality factor cavities. Measurement procedures are achieved using only one microwave source and two signals extracted from this feedback loop. Phase noise performance better than −130 dBc/Hz can be achieved through the proposed procedure. © 2014 Wiley Periodicals, Inc. Microwave Opt Technol Lett 56:2304–2310, 2014
Design of a closely‐spaced, multiple‐element parasitic antenna array
Authors: Xue Dong , Li Yang
Published: July 2014

A new design of a closely‐spaced, multiple‐element parasitic antenna array is proposed based on the identified dominant surface wave mechanism. The optimum surface wave phase velocity, which leads to the maximum antenna gain, is determined for a fixed length array. The antenna input impedance is presented and optimized using folding technique. Both numerical simulations and measurements are implemented. © 2014 Wiley Periodicals, Inc. Microwave Opt Technol Lett 56:2374–2377, 2014
Characterization and time domain analysis of coaxial connector junctions
Authors: Zhu Qian C. , Ji Yu
Published: July 2014

We propose a simple circuit model for coaxial connector junctions and apply time domain analysis to examine various connector defects. Close approximations to the measured time domain response for calibration standards provide a possibility for error model embedding in vector network analyzer measurements. © 2014 Wiley Periodicals, Inc. Microwave Opt Technol Lett 56:2439–2444, 2014
Fan‐shaped antenna with triband‐notched characteristic for UWB applications
Authors: Ojaroudi N. , Mehranpour M. , Ghadimi N.
Published: July 2014

In this article, a novel design of ultrawideband (UWB) microstrip monopole antenna with enhanced bandwidth and triple band‐notched characteristics has been presented. The antenna consists of fan‐shaped radiating patch with a pair of L‐shaped parasitic structure, a feed‐line with an S‐shaped step‐impedance resonator (SIR) slot and modified ground plane with pairs of T‐shaped strips protruded inside the rectangular slots. In the proposed design, by cutting two rectangular slots with pairs of protruded T‐shaped strips in the ground plane, additional resonances are excited and much wider impedance bandwidth can be produced. Using these modified structures, the usable upper frequency of the antenna is extended from 10.3 to 17.4 GHz. To generate a single band‐notched function, we add a pair of L‐shaped parasitic structures to the fan‐shaped radiating patch. Also, by cutting the S‐shaped SIR at the feed line, dual and triple band‐notched properties are achieved. The measured results reveal that the presented dual band‐notched antenna offers a very wide bandwidth from 2.8 to 17.4 GHz, with three notched bands around of 5–6 GHz wireless local area network, 7.25–7.75 GHz downlink of X‐band satellite communication system, and 8.02–8.4 GHz International Telecommunication Union bands. The antenna configuration is simple, easy to fabricate and can be integrated into UWB systems. © 2014 Wiley Periodicals, Inc. Microwave Opt Technol Lett 56:2426–2430, 2014
Preparation, characterization, and properties of silicate/polyurethaneurea composites based on dipropylene glycol dibenzoate
Authors: Yang Zhengpeng , Zhang Wujun , Guan Xuemao , Zhang Chunjing
Published: July 2014

The silicate/polyurethaneurea composites based on dipropylene glycol dibenzoate were prepared via a room‐temperature‐cured process. Characterization of the composites was accomplished using scanning electron microscope, X‐ray diffraction, Fourier transformation infrared spectrum, and Raman spectroscopy, and the mechanism, mechanical properties and stability were discussed in detail. The obtained results indicated that a durable silicate/polyurethaneurea composite with inorganic‐organic network structure had been successfully prepared. The composites were thermally stable below 210°C and the compressive and flexural strength of the material could reach 42.6 and 29.2 MPa after curing for 6 h, respectively. POLYM. COMPOS., 37–43, 2016. © 2014 Society of Plastics Engineers
Duth: a user‐friendly dual‐factor authentication for Android smartphone devices
Authors: Zhu Hui , Lin Xiaodong , Zhang Yun , Lu Rongxing
Published: July 2014

With the pervasiveness of smartphones and the richness of mobile apps, many people are storing increasingly sensitive data on them, in greater quantities. In order to protect this sensitive information from misuse due to loss, or other accidental reasons, strong smartphone authentication has become imperative and has received considerable attention in recent years. However, when we directly implement traditional authentication schemes in smartphone devices, the balance between security and user‐friendliness of authentication becomes challenging, mainly because of the input‐in‐motion environments. In this paper, without adding extra hardware devices, we present a user‐friendly, dual‐factor authentication scheme called Duth, for Android smartphone devices. Specifically, the proposed Duth scheme is characterized by utilizing the spatial and time features of the user‐writing process as two factors of authentication; a user can be authenticated only if these two features are fulfilled. We implement Duth in Java as a library, which we make publicly available. With extensive discussions on parameter selection, we choose proper parameters and implement Duth on a smartphone with Android 2.3 for experiments, and the experiment results demonstrate that Duth can indeed achieve efficient and effective dual‐factor authentication. Copyright © 2014 John Wiley & Sons, Ltd.
Our Recent Progress on the Intramolecular Diels–Alder Reaction Approach in Natural Products Synthesis: Synthetic Studies of the Octahydronaphthalene Substructure of Versipelostatins and the A/B/C‐Tricyclic Substructure of GKK1032s
Authors: Tadano Kin‐Ichi
Published: July 2014

During this decade, the enantio‐ and stereoselective synthesis of natural products has been actively explored in the author's laboratory. In this account, the author outlines practical syntheses of the polycyclic substructures of two novel structurally formidable antibiotics, namely, the trans‐fused octahydronaphthalene moiety of versipelostatins and the A/B/C‐tricyclic decahydrofluorene moiety of GKK1032s. Both syntheses have been achieved with remarkable regio‐ and stereoselectivity via intramolecular Diels–Alder reactions using well‐designed enantiomeric substrates.
Impact Evaluation of Exit Strategy in Fuzzy Portfolio‐based Investment
Authors: Li You , Wang Bo , Watada Junzo
Published: July 2014

This paper focuses on the impacts of exit strategy in existing fuzzy portfolio selection models. In the securities market, the term ‘exit’ means that the investor may sell his/her equity on account of some exogenous or endogenous incentives, especially when the security price becomes higher than his/her expectation or lower than his/her tolerance. It is a common problem that all investors need to face in the investment horizon. There have been various studies reported in the current literature employing fuzzy set theory to handle the uncertainty of portfolio selection. Nevertheless, none of these studies considers the influence caused by exit strategy which will be executed once a security price fluctuates out of the expected interval. In this paper, we first secure the future returns of each security by profit/loss exit points (prices) before rebuilding fuzzy portfolio selection models. Next, the properties of exit points are analyzed. Then a meta‐heuristic method is proposed to analyze the differences between the new models' experimental results and those of previous methods. Finally, we discuss how to assign proper exit point values to different securities based on different risk attitudes, and apply our approach to a real application on the New York Stock Exchange. © 2014 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.