bluuebunny/crossref_metadata_2025 huggingface dataset:
Suppression and facilitation of human neural responses
Authors: Schallmo Michael-Paul , Kale Alexander M , Millin Rachel , Flevaris Anastasia V , Brkanac Zoran , Edden Richard AE , Bernier Raphael A , Murray Scott O
Published: January 2018

Efficient neural processing depends on regulating responses through suppression and facilitation of neural activity. Utilizing a well-known visual motion paradigm that evokes behavioral suppression and facilitation, and combining five different methodologies (behavioral psychophysics, computational modeling, functional MRI, pharmacology, and magnetic resonance spectroscopy), we provide evidence that challenges commonly held assumptions about the neural processes underlying suppression and facilitation. We show that: (1) both suppression and facilitation can emerge from a single, computational principle – divisive normalization; there is no need to invoke separate neural mechanisms, (2) neural suppression and facilitation in the motion-selective area MT mirror perception, but strong suppression also occurs in earlier visual areas, and (3) suppression is not primarily driven by GABA-mediated inhibition. Thus, while commonly used spatial suppression paradigms may provide insight into neural response magnitudes in visual areas, they should not be used to infer neural inhibition.
Cell volume changes contribute to epithelial morphogenesis in zebrafish Kupffer’s vesicle
Authors: Dasgupta Agnik , Merkel Matthias , Clark Madeline J , Jacob Andrew E , Dawson Jonathan Edward , Manning M Lisa , Amack Jeffrey D
Published: January 2018

How epithelial cell behaviors are coordinately regulated to sculpt tissue architecture is a fundamental question in biology. Kupffer’s vesicle (KV), a transient organ with a fluid-filled lumen, provides a simple system to investigate the interplay between intrinsic cellular mechanisms and external forces during epithelial morphogenesis. Using 3-dimensional (3D) analyses of single cells we identify asymmetric cell volume changes along the anteroposterior axis of KV that coincide with asymmetric cell shape changes. Blocking ion flux prevents these cell volume changes and cell shape changes. Vertex simulations suggest cell shape changes do not depend on lumen expansion. Consistent with this prediction, asymmetric changes in KV cell volume and shape occur normally when KV lumen growth fails due to leaky cell adhesions. These results indicate ion flux mediates cell volume changes that contribute to asymmetric cell shape changes in KV, and that these changes in epithelial morphology are separable from lumen-generated forces.
TGF-β uses a novel mode of receptor activation to phosphorylate SMAD1/5 and induce epithelial-to-mesenchymal transition
Authors: Ramachandran Anassuya , Vizán Pedro , Das Debipriya , Chakravarty Probir , Vogt Janis , Rogers Katherine W , Müller Patrick , Hinck Andrew P , Sapkota Gopal P , Hill Caroline S
Published: January 2018

The best characterized signaling pathway downstream of transforming growth factor β (TGF-β) is through SMAD2 and SMAD3. However, TGF-β also induces phosphorylation of SMAD1 and SMAD5, but the mechanism of this phosphorylation and its functional relevance is not known. Here, we show that TGF-β-induced SMAD1/5 phosphorylation requires members of two classes of type I receptor, TGFBR1 and ACVR1, and establish a new paradigm for receptor activation where TGFBR1 phosphorylates and activates ACVR1, which phosphorylates SMAD1/5. We demonstrate the biological significance of this pathway by showing that approximately a quarter of the TGF-β-induced transcriptome depends on SMAD1/5 signaling, with major early transcriptional targets being the ID genes. Finally, we show that TGF-β-induced epithelial-to-mesenchymal transition requires signaling via both the SMAD3 and SMAD1/5 pathways, with SMAD1/5 signaling being essential to induce ID1. Therefore, combinatorial signaling via both SMAD pathways is essential for the full TGF-β-induced transcriptional program and physiological responses.
Mitochondria-specific photoactivation to monitor local sphingosine metabolism and function
Authors: Feng Suihan , Harayama Takeshi , Montessuit Sylvie , David Fabrice PA , Winssinger Nicolas , Martinou Jean-Claude , Riezman Howard
Published: January 2018

Photoactivation ('uncaging’) is a powerful approach for releasing bioactive small-molecules in living cells. Current uncaging methods are limited by the random distribution of caged molecules within cells. We have developed a mitochondria-specific photoactivation method, which permitted us to release free sphingosine inside mitochondria and thereafter monitor local sphingosine metabolism by lipidomics. Our results indicate that sphingosine was quickly phosphorylated into sphingosine 1-phosphate (S1P) driven by sphingosine kinases. In time-course studies, the mitochondria-specific uncaged sphingosine demonstrated distinct metabolic patterns compared to globally-released sphingosine, and did not induce calcium spikes. Our data provide direct evidence that sphingolipid metabolism and signaling are highly dependent on the subcellular location and opens up new possibilities to study the effects of lipid localization on signaling and metabolic fate.
Contemporary Routes of Cannabis Consumption: A Primer for Clinicians
Authors: Peters Jeramy , Chien Joseph
Published: January 2018

Although cannabis use is federally prohibited, medical cannabis is legal in some form in 30 states and the District of Columbia, and recreational use is legal in 8 states and the District of Columbia. The increasing legal acceptance of cannabis has led to a burgeoning industry that is producing an expanding variety of cannabis products. Physicians and other health care professionals should be aware of modern forms of cannabis consumption, as well as variations in tetrahydrocannabinol concentrations, to improve assessment of cannabis use and approach to treatment. This review aims to familiarize clinicians with modern forms of cannabis consumption and enable comparisons between disparate cannabis products.
Association Between Undergraduate Performance Predictors and Academic and Clinical Performance of Osteopathic Medical Students
Authors: Agahi Farshad , Speicher Mark R. , Cisek Grace
Published: January 2018

Context

Medical schools use a variety of preadmission indices to select potential students. These indices generally include undergraduate grade point average (GPA), Medical College Admission Test (MCAT) scores, and preadmission interviews.

Objective

To investigate whether the admission indices used by Midwestern University Arizona College of Osteopathic Medicine are associated with the academic and clinical performance of their students.

Methods

Associations between the prematriculation variables of undergraduate science GPA, undergraduate total GPA, MCAT component scores, and interview scores and the academic and clinical variables of the first- and second-year medical school GPA, Comprehensive Osteopathic Medical Licensing Examination-USA (COMLEX-USA) Level 1 and Level 2-Cognitive Evaluation (CE) total and discipline scores, scores in clinical rotations for osteopathic competencies, COMLEX-USA Level 2-Performance Evaluation passage, and match status were evaluated. Two-tailed Pearson product-moment correlations with a Bonferroni adjustment were used to examine these relationships.

Results

The traditional predictors of science and total undergraduate GPA as well as total and component MCAT scores had small to moderate associations with first- and second-year GPA, as well as COMLEX-USA Level 1 and Level 2-CE total scores. Of all predictors, only the MCAT biological sciences score had a statistically significant correlation with failure of the COMLEX-USA Level 2-Performance Evaluation examination (P=.009). Average interview scores were associated only with the osteopathic competency of medical knowledge (r=0.233; n=209;P=.001), as assessed by clerkship preceptors. No predictors were associated with scores in objective structured clinical encounters or with failing to match to a residency position.

Conclusion

The data indicate that traditional predictors of academic performance (undergraduate GPA, undergraduate science GPA, and MCAT scores) have small to moderate association with medical school grades and performance on COMLEX-USA Level 1 and Level 2-CE. This finding requires additional research into the value of the interview in the medical school admissions process and the availability of alternatives that allow better prediction and assessment of applicant performance.
О ПРИНЦИПЕ МИНИМИЗАЦИИ ЭМПИРИЧЕСКОГО РИСКА НА ОСНОВЕ УСРЕДНЯЮЩИХ АГРЕГИРУЮЩИХ ФУНКЦИЙ, "Доклады Академии наук"
Authors: Шибзухов З.М.
Published: January 2018

В работе предлагается расширенный вариант принципа минимизации эмпирического риска. Он строится на  основе применения усредняющих агрегирующих функций вместо среднего арифметического для вычисления эмпирического риска. Это оправдано, если распределение потерь имеет выбросы или существенно искажено, отчего оценка риска с  самого начала является смещённой. Поэтому для оптимизации параметров следует изначально использовать робастную оценку среднего риска. Такие оценки можно построить, используя усредняющие агрегирующие функции, которые являются решением задачи минимизации штрафной функции за  отклонение от  своего среднего значения. В  работе предложена схема итеративного перевзвешивания для численного решения задачи минимизации эмпирического риска. Приведены иллюстративные примеры построения робастной процедуры оценки параметров в  задаче линейной регрессии и задаче линейного разделения двух классов на  базе использования усредняющей функции среднего, заменяющей a-квантиль.
ИЗМЕНЕНИЕ ФУНКЦИОНАЛЬНОЙ АКТИВНОСТИ МИТОХОНДРИЙ, ВЫДЕЛЕННЫХ ИЗ КЛЕТОК ПЕЧЕНИ КРЫС, ПРОШЕДШИХ ПРЕДАДАПТАЦИЮ К СВЕРХНИЗКИМ КОНЦЕНТРАЦИЯМ ДЕЙТЕРИЯ, "Доклады Академии наук"
Authors: Джимак С.С. , Басов А.А. , Волченко Н.Н. , Самков А.А. , Федулова Л.В. , Барышев М.Г.
Published: January 2018

При инкубации в среде, обеднённой дейтерием, выявили рост на 35% генерации перекиси водорода митохондриями, выделенными из гепатоцитов крыс, потреблявших питьевую воду с пониженной концентрацией дейтерия (46 ppm), по сравнению с митохондриями из клеток печени крыс, потреблявших воду с концентрацией дейтерия 152 ppm. Добавление в среду инкубации сукцината привело к увеличению продукции перекиси водорода на 44-81%, различия в генерации H2O2 между органеллами, инкубированными в среде с содержанием дейтерия 46 и 152 ppm, уменьшились на 14%. Выявленное изменение функциональной активности митохондрий свидетельствует о способности организма животных адаптироваться к режиму потребления питьевой воды, обеднённой дейте­рием, что, возможно, обусловлено формированием трансмембранного изотопного градиента D/H.
ПЛАТИНОНОСНОСТЬ МЕДНО-НИКЕЛЕВЫХ МЕСТОРОЖДЕНИЙ И РУДОПРОЯВЛЕНИЙ CТАНОВОЙ НИКЕЛЕНОСНОЙ ПРОВИНЦИИ (ДАЛЬНИЙ ВОСТОК, РОССИЯ), "Доклады Академии наук"
Authors: Мельников А.В. , Стриха В.Е. , Моисеенко В.Г.
Published: January 2018

Приведены сведения о платиноносности Cu-Ni-месторождений и рудопроявлений Становой никеленосной провинции Верхнего Приамурья. С учётом новых данных по геологии, геохимии, вещественному составу руд приведены описание и сравнительный анализ месторождений и рудопроявлений платиносодержащих Cu-Ni-руд. Охарактеризованы предпосылки формирования и критерии прогноза и поисков крупных месторождений платиносодержащих Cu-Ni-руд в Верхнем Приамурье.
ЭПИЛЕПТИЧЕСКИЙ СТАТУС, ВЫЗВАННЫЙ ПЕНТИЛЕНТЕТРАЗОЛОМ, УВЕЛИЧИВАЕТ КРАТКОВРЕМЕННУЮ СИНАПТИЧЕСКУЮ ФАСИЛИТАЦИЮ В ГИППОКАМПЕ ЮВЕНИЛЬНЫХ КРЫС, "Доклады Академии наук"
Authors: Постникова Т.Ю. , Трофимова А. М. , Зайцев А.В. , Магазаник Л.Г.
Published: January 2018

Изучали влияние эпилептического статуса (ЭС) на кратковременную синаптическую пластичность. На переживающих срезах гиппокампа, регистрировали амплитуды полевых потенциалов при внеклеточной стимуляции коллатералей Шаффера. Наибольшие изменения кратковременной пластичности были выявлены в первые сутки после ЭС, на третий и седьмой дни отличий от контроля не зарегистрировали. Полученные результаты свидетельствуют о том, что в первые сутки после формирования ЭС вероятность высвобождения медиатора в синапсах гиппокампа уменьшается, что может являться одним из компенсаторных механизмов, предотвращающих судорожную активность.
Modulation of GSK3β autoinhibition by Thr‐7 and Thr‐8
Authors: Tong Yixin , Park Sohyun , Wu Di , Harris Thurl E. , Moskaluk Christopher A. , Brautigan David L. , Fu Zheng
Published: January 2018

Glycogen synthase kinase 3β (GSK‐3β) is a pivotal signaling node that regulates a myriad of cellular functions and is deregulated in many pathological conditions, making it an attractive therapeutic target. Inhibitory Ser‐9 phosphorylation of GSK3β by AKT is an important mechanism for negative regulation of GSK3β activity upon insulin stimulation. Here, we report that Thr‐7 and Thr‐8 residues located in the AKT/PKB substrate consensus sequence on GSK3β are essential for insulin‐stimulated Ser‐9 phosphorylation in vivo and for GSK3β inactivation. Intestinal cell kinase (ICK) phosphorylates GSK3β Thr‐7 in vitro and in vivo. Thr‐8 phosphorylation partially inhibits GSK3β, but Thr‐7 phosphorylation promotes GSK3β activity and blocks phospho‐Ser‐9‐dependent GSK3β autoinhibition. Our findings uncover novel mechanistic and signaling inputs involved in the autoinhibition of GSK3β.
Mercury – Method for the determination of vapour from mercury and its inorganic compounds in workplace air using atomic absorption spectrometry [Air Monitoring Methods, 2017]
Authors: Hebisch R. , Fröhlich N. , Houben T. , Schneider W. , Brock T.H. , Hartwig A. ,   MAK Commission
Published: January 2018

This analytical method is a validated measurement procedure for the determination of mercury vapours in workplace air using atomic absorption spectrometry in a concentration range of one thousandth up to twice the currently valid Occupational Exposure Limit (OEL) or MAK value of 0.02 mg/m
3
. Both personal and stationary sampling can be performed for risk assessment at work. Sampling is carried out by drawing a defined volume of air through an adsorption tube filled with hopcalite (mixture of MnO
2
and CuO) using a flow‐regulated pump. The flow rate is set to 250 mL/min with a recommended air sample volume of approx. 30 L at a sampling period of 2 hours. After sampling the loaded hopcalite is transferred into a quartz boat and the collected mercury can be analysed directly via atomic absorption spectrometry (AAS). The quantitative determination is based on a calibration function obtained by means of a 10‐point calibration. The limit of quantification is 0.013 mg/m
3
based on an air sample volume of approx. 30 L with an expanded uncertainty between 18 and 21%.

Joint Publication of the Analytical Subcommittee of the Chemistry Board of Experts of the Expert Committee Raw Materials and Chemical Industry of the German Social Accident Insurance and the Working Group “Air Analyses” of the Permanent Senate Commission of the DFG for the Investigation of Health Hazards of Chemical Compounds in the Work Area.
Methyl‐tert‐butylether – Bestimmung von Methyl‐tert‐butylether in Blut und Urin mittels Headspace‐Gaschromatographie‐Massenspektrometrie [Biomonitoring Methods in German language, 2018]
Authors: Hoppe H.‐W. , Zarniko M. , Müller J. , Göen T. , Hartwig A. ,   MAK Commission
Published: January 2018

The working group “Analyses in Biological Materials” of the Permanent Senate Commission for the Investigation of Health Hazards of Chemical Compounds in the Work Area verified the present biomonitoring method.

The described analytical method allows the specific and sensitive determination of methyl tert‐butyl ether (MTBE) in blood and urine of persons occupationally exposed to this substance. The volatile MTBE is determined using static headspace GC‐MS. Before analysing an aliquot of the headspace, the urine and blood samples are diluted 1:10 with water, spiked with internal standard and incubated for 45 min at 60 °C. The isotope‐labelled d3‐MTBE serves as internal standard. Aqueous standard solutions are used for calibration.

The method was extensively validated and the reliability data were confirmed by an independent laboratory, which has established and cross‐checked the whole procedure.
Furan [MAK Value Documentation, 2006]
Authors: Hartwig A. ,   MAK Commission
Published: January 2018

The German Commission for the Investigation of Health Hazards of Chemical Compounds in the Work Area has evaluated all toxicological endpoints of furan [
110‐00‐9
].

Data indicate a genotoxic potential of furan especially due to the mutagenic metabolite
cis
‐2‐butene‐1,4‐dial. In carcinogenicity studies hepatocellular carcinomas were observed in rats and mice and cholangiocarcinomas in rats starting at the lowest tested dose of 2 mg/kg body weight and day with an incidence of at least 86%. A no observed adverse effect level (NOAEL) was not obtained. Therefore, furan is classified into Category 2 for carcinogens.

Furan is not classified into a Category for Germ Cell Mutagens as effects in testes and ovaries are only observed at doses that induce severe liver toxicity.

Calculations show that dermal absorption can contribute substantially to the systemic toxicity. Therefore, furan is designated with an “H”.

There are no studies investigating the developmental toxicity and sensitizing potential of furan.
2‐Butoxyethanol [MAK Value Documentation in German language, 2018]
Authors: Hartwig A. ,   MAK Commission
Published: January 2018

The German Commission for the Investigation of Health Hazards of Chemical Compounds in the Work Area has re‐evaluated the carcinogenicity classification of 2‐butoxyethanol [
111‐76‐2
]. In long‐term studies, 2‐butoxyethanol resulted in hepatocellular carcinomas, haemangiosarcomas and forestomach tumours in mice and phaeochromocytomas in rats and was classified in Carcinogen Category 4.

New studies indicate that the hepatic tumours and the phaeochromocytomas are consequences of the haemolysis which is caused by the metabolite butoxyacetic acid. The forestomach tumours in mice are judged to be irrelevant for humans. There are differences between rats and humans concerning the formation and the haemolytic potency of butoxyacetic acid, which renders humans much less susceptible for haemolysis than rats, although humans can develop signs of haemolysis after severe oral intoxication. However, the CNS‐depression and the irritation caused by 2‐butoxyethanol precludes that humans are exposed regularly to 2‐butoxyethanol concentrations at the workplace which might result in significant haemolysis. Therefore, the Commission has removed 2‐butoxyethanol from the Carcinogen Category 4.
Effective and Selective Anti‐Cancer Protein Delivery via All‐Functions‐in‐One Nanocarriers Coupled with Visible Light‐Responsive, Reversible Protein Engineering
Authors: He Hua , Chen Yongbing , Li Yongjuan , Song Ziyuan , Zhong Yinan , Zhu Rongying , Cheng Jianjun , Yin Lichen
Published: January 2018

Efficient intracellular delivery of protein drugs and tumor‐specific activation of protein functions are critical toward anti‐cancer protein therapy. However, an omnipotent protein delivery system that can harmonize the complicated systemic barriers as well as spatiotemporally manipulate protein function is lacking. Herein, an “all‐functions‐in‐one” nanocarrier doped with photosensitizer (PS) is developed and coupled with reactive oxygen species (ROS)‐responsive, reversible protein engineering to realize cancer‐targeted protein delivery, and spatiotemporal manipulation of protein activities using long‐wavelength visible light (635 nm) at low power density (5 mW cm−2). Particularly, RNase A is caged with H2O2‐cleavable phenylboronic acid to form 4‐nitrophenyl 4‐(4,4,5,5‐tetramethyl‐1,3,2‐dioxaborolan‐2‐yl)benzyl carbonate (NBC)‐modified RNase (RNBC), which is encapsulated in acid‐degradable, ketal‐crosslinked PEI (KPEI)‐based nanocomplexes (NCs) coated with PS‐modified hyaluronic acid (HA). Such NCs harmonize the critical processes for protein delivery, wherein HA coating renders NCs with long blood circulation and cancer cell targeting, and KPEI enables endosomal escape as well as acid‐triggered intracellular RNBC release. Tumor‐specific light irradiation generates H2O2 to kill cancer cells and restore the protein activity, thus achieving synergistic anti‐cancer efficacy. It is the first time to photomanipulate protein functions by coupling ROS‐cleavable protein caging with PS‐mediated ROS generation, and the “all‐functions‐in‐one” nanocarrier represents a promising example for the programmed anti‐cancer protein delivery.
Removal of yield‐stress fluids from pipework using water
Authors: Palabiyik Ibrahim , Lopez‐Quiroga Estefania , Robbins Phillip T. , Goode Kylee R. , Fryer Peter J.
Published: January 2018

The emptying of product from process plant is a significant multiphase flow problem in food and personal care industries, controlling both product recovery, and cleaning time. Product and operational losses can be significant, especially with viscous products. It is necessary to maximize product recovery while minimizing cleaning time and effluent volume. The removal of a range of products from fully filled pipework using water has been characterized and monitored by weighing pipes at intervals and by inline turbidity probe. Data is presented for a range of products (toothpaste, hand cream, apple sauce, yoghurt, and shower gel) that have been cleaned from two pipe systems. The data can be fitted by a linear relationship between a dimensionless cleaning time, and the ratio of the product yield stress to the surface shear stress. The effect of pipe fittings is to reduce cleaning times, reflecting increased shear/energy dissipation in the pipe. © 2018 The Authors AIChE Journal published by Wiley Periodicals, Inc. on behalf of American Institute of Chemical Engineers AIChE J, 64: 1517–1527, 2018
Nasal variation in relation to high‐altitude adaptations among Tibetans and Andeans
Authors: Butaric Lauren N. , Klocke Ross P.
Published: January 2018

Objectives

High‐altitude (>2500 m) populations face several pressures, including hypoxia and cold‐dry air, resulting in greater respiratory demand to obtain more oxygen and condition inspired air. While cardiovascular and pulmonary adaptations to high‐altitude hypoxia have been extensively studied, adaptations of upper‐respiratory structures, e.g., nasal cavity, remain untested. This study investigates whether nasal morphology presents adaptations to hypoxic (larger noses) and/or cold‐dry (tall/narrow noses) conditions among high‐altitude samples.

Methods

CT scans of two high‐ and four low‐altitude samples from diverse climates were collected (n = 130): high‐altitude Tibetans and Peruvians; low‐altitude Peruvians, Southern Chinese (temperate), Mongolian‐Buriats (cold‐dry), and Southeast Asians (hot‐wet). Facial and nasal distances were calculated from 3D landmarks placed on digitally‐modeled crania. Temperature, precipitation, and barometric pressure data were also obtained.

Results

Principal components analysis and analyses of variance primarily indicate size‐related differences among the cold‐dry (Mongolian‐Buriats) and hot‐wet (Southeast Asians) adapted groups. Two‐block partial least squares (PLS) analysis show weak relationships between size‐standardized nasal dimensions and environmental variables. However, among PLS1 (85.90% of covariance), Tibetans display relatively larger nasal cavities related to lower temperatures and barometric pressure; regression analyses also indicate high‐altitude Tibetans possess relatively larger internal nasal breadths and heights for their facial size.

Conclusions

Overall, nasal differences relate to climate among the cold‐dry and hot‐wet groups. Specific nasal adaptations were not identified among either Peruvian group, perhaps due to their relatively recent migration history and population structure. However, high‐altitude Tibetans seem to exhibit a compromise in nasal morphology, serving in increased oxygen uptake, and air‐conditioning processes.
Growth pattern of Rahman syndrome
Authors: Takenouchi Toshiki , Uehara Tomoko , Kosaki Kenjiro , Mizuno Seiji
Published: January 2018

Recently, in a cohort study with “overgrowth syndrome with intellectual disability,” five subjects were reported to have de novo heterozygous truncating variants in HIST1H1E, which encodes linker histone H 1.4. However, their growth pattern appeared complex that four out of five patients had a decreasing height percentile over time, and three of these patients began with above‐average heights but exhibited reductions to average heights or below when they were older. Herein, we report a female patient with intellectual disability and distinctive facial features including a wide nasal bridge and prominent cheek bones. She did not exhibit skeletal overgrowth, but she had a short stature at 21 years of age. An exome analysis identified a de novo heterozygous 1‐bp duplication in HIST1H1E, that is, c.433dup p.(Ala145Glyfs*51). The physical features of the proposita were essentially the same as those observed in patients with the aforementioned HIST1H1E‐related overgrowth syndrome. Our review of the growth trajectories in seven patients showed that five of seven patients did not exhibit skeletal overgrowth. This “lack of overgrowth in overgrowth syndrome” is reminiscent of a subset of patients with a short stature who have Sotos syndrome, a prototypic overgrowth syndrome. Considering this complexity in growth, this newly identified condition should be referred to as Rahman syndrome.
Interrupted Baeyer–Villiger Rearrangement: Building A Stereoelectronic Trap for the Criegee Intermediate
Authors: Vil' Vera A. , dos Passos Gomes Gabriel , Bityukov Oleg V. , Lyssenko Konstantin A. , Nikishin Gennady I. , Alabugin Igor V. , Terent'ev Alexander O.
Published: January 2018

The instability of hydroxy peroxyesters, the elusive Criegee intermediates of the Baeyer–Villiger rearrangement, can be alleviated by selective deactivation of the stereoelectronic effects that promote the 1,2‐alkyl shift. Stable cyclic Criegee intermediates constrained within a five‐membered ring can be prepared by mild reduction of the respective hydroperoxy peroxyesters (β‐hydroperoxy‐β‐peroxylactones) which were formed in high yields in reaction of β‐ketoesters with BF3⋅Et2O/H2O2.
Cytochrome‐P450‐Induced Ordering of Microsomal Membranes Modulates Affinity for Drugs
Authors: Barnaba Carlo , Sahoo Bikash Ranjan , Ravula Thirupathi , Medina‐Meza Ilce G. , Im Sang‐Choul , Anantharamaiah G. M. , Waskell Lucy , Ramamoorthy Ayyalusamy
Published: January 2018

Although membrane environment is known to boost drug metabolism by mammalian cytochrome P450s, the factors that stabilize the structural folding and enhance protein function are unclear. In this study, we use peptide‐based lipid nanodiscs to “trap” the lipid boundaries of microsomal cytochrome P450 2B4. We report the first evidence that CYP2B4 is able to induce the formation of raft domains in a biomimetic compound of the endoplasmic reticulum. NMR experiments were used to identify and quantitatively determine the lipids present in nanodiscs. A combination of biophysical experiments and molecular dynamics simulations revealed a sphingomyelin binding region in CYP2B4. The protein‐induced lipid raft formation increased the thermal stability of P450 and dramatically altered ligand binding kinetics of the hydrophilic ligand BHT. These results unveil membrane/protein dynamics that contribute to the delicate mechanism of redox catalysis in lipid membrane.
Palladium‐Catalyzed C−H Silylation through Palladacycles Generated from Aryl Halides
Authors: Lu Ailan , Ji Xiaoming , Zhou Bo , Wu Zhuo , Zhang Yanghui
Published: January 2018

A highly efficient palladium‐catalyzed disilylation reaction of aryl halides through C−H activation has been developed for the first time. The reaction has broad substrate scope. A variety of aryl halides can be disilylated by three types of C−H activation, including C(sp2)−H, C(sp3)−H, and remote C−H activation. In particular, the reactions are also unusually efficient. The yields are essentially quantitative in many cases, even in the presence of less than 1 mol % catalyst and 1 equivalent of the silylating reagent under relatively mild conditions. The disilylated biphenyls can be converted into disiloxane‐bridged biphenyls.
Designed Long‐Lived Emission from CdSe Quantum Dots through Reversible Electronic Energy Transfer with a Surface‐Bound Chromophore
Authors: La Rosa Marcello , Denisov Sergey A. , Jonusauskas Gediminas , McClenaghan Nathan D. , Credi Alberto
Published: January 2018

The size‐tunable emission of luminescent quantum dots (QDs) makes them highly interesting for applications that range from bioimaging to optoelectronics. For the same applications, engineering their luminescence lifetime, in particular, making it longer, would be as important; however, no rational approach to reach this goal is available to date. We describe a strategy to prolong the emission lifetime of QDs through electronic energy shuttling to the triplet excited state of a surface‐bound molecular chromophore. To implement this idea, we made CdSe QDs of different sizes and carried out self‐assembly with a pyrene derivative. We observed that the conjugates exhibit delayed luminescence, with emission decays that are prolonged by more than 3 orders of magnitude (lifetimes up to 330 μs) compared to the parent CdSe QDs. The mechanism invokes unprecedented reversible quantum dot to organic chromophore electronic energy transfer.
Isolation of a Cationic Platinum(II) σ‐Silane Complex
Authors: Ríos Pablo , Fouilloux Hugo , Vidossich Pietro , Díez Josefina , Lledós Agustí , Conejero Salvador
Published: January 2018

The platinum complex [Pt(ItBuiPr′)(ItBuiPr)][BArF] interacts with tertiary silanes to form stable (<0 °C) mononuclear PtII σ‐SiH complexes [Pt(ItBuiPr′)(ItBuiPr)(η1‐HSiR3)][BArF]. These compounds have been fully characterized, including X‐ray diffraction methods, as the first examples for platinum. DFT calculations (including electronic topological analysis) support the interpretation of the coordination as an unusual η1‐SiH. However, the energies required for achieving a η2‐SiH mode are rather low, and is consistent with the propensity of these derivatives to undergo Si−H cleavage leading to the more stable silyl species [Pt(SiR3)(ItBuiPr)2][BArF] at room temperature.
Magnetic nanoparticle‐tethered Schiff base–palladium(II): Highly active and reusable heterogeneous catalyst for Suzuki–Miyaura cross‐coupling and reduction of nitroarenes in aqueous medium at room temperature
Authors: Manjunatha K. , Koley Tuhin S. , Kandathil Vishal , Dateer Ramesh B. , Balakrishna Geetha , Sasidhar B. S. , Patil Shivaputra A. , Patil Siddappa A.
Published: January 2018

As a continuation of our efforts to develop new heterogeneous nanomagnetic catalysts for greener reactions, we identified a Schiff base–palladium(II) complex anchored on magnetic nanoparticles (SB‐Pd@MNPs) as a highly active nanomagnetic catalyst for Suzuki–Miyaura cross‐coupling reactions between phenylboronic acid and aryl halides and for the reduction of nitroarenes using sodium borohydride in an aqueous medium at room temperature. The SB‐Pd@MNPs nanomagnetic catalyst shows notable advantages such as simplicity of operation, excellent yields, short reaction times, heterogeneous nature, easy magnetic work up and recyclability. Characterization of the synthesized SB‐Pd@MNPs nanomagnetic catalyst was performed with various physicochemical methods such as attenuated total reflectance infrared spectroscopy, UV–visible spectroscopy, inductively coupled plasma atomic emission spectroscopy, energy‐dispersive X‐ray spectroscopy, field‐emission scanning electron microscopy, transmission electron microscopy, powder X‐ray powder diffraction, thermogravimetric analysis and Brunauer–Emmett–Teller surface area analysis.
Novel soluble carbazole‐based poly(aryl ethers): Preparation, properties, and application for dispersing multiwalled carbon nanotubes
Authors: Lin Li , Wu Xian , Han Yuntao , Zhang Haibo , Jiang Zhenhua , Chen Zheng
Published: January 2018

Effectively dispersing of carbon nanotubes (CNTs) is the key to producing high performance CNTs/poly(aryl ethers) (PAEs) composite materials. Here, a series of novel soluble carbazole‐based PAEs with different alkyl side‐chains were synthesized corresponding polymers P1, P2, P3, and P4, and characterized clearly by 1H NMR and IR. All the polymers exhibited good mechanical properties and thermostabilities (Tg ∼ 128–212 °C, Td5% ∼ 450–499 °C) as PAEs. Due to containing lots of large π‐conjugated carbazole derivative units and possess suitable solubility, these non‐conjugated polymers can wrap and disperse MWNTs well (238–416 mg/L) in CHCl3, and the similar work has been reported rarely. This excellent property makes these polymers become a promising and ideal type solubilizer for CNTs/PAEs composite. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 46250.
Educational interactive LabVIEW programming of a 3D canal surface design
Authors: Allawi Faridoun A.M.
Published: January 2018

Educational computer programming in geometrical modeling is an interactive dynamic educational method which helps to visualize; interactively and graphically; 3D geometrical models under different design conditions. Students using geometrical modeling in hydraulics can get large amount of geometrical data describing the x, y, and z coordinates of any circular cross‐section of the designed 3D canal transition, a step which is very important in the modeling of field and laboratory 3D canal sections. They can visually and interactively perform mathematical analysis of very complicated models very easily. Educational programming of geometrical modeling is very similar to experimental modeling in which the students gets feedback from the computer program and adjust—if necessary—the model specifications and properties to get the best engineering design. In this paper, the LabVIEW Platform and the 3D Bezier surface design method will be used by the students, as an educational interactive computer programming, for the design of a 3D open circular canal cross‐section having a hydraulic constriction and, a bottom slope of certain dimensions.
The effect of relational benefits in loyalty programmes: Evidence from Chinese milk formula customer clubs
Authors: Yang Song , Yu Siu Lung (Kevin) , Bruwer Johan
Published: January 2018

Although the value of relational benefits has been recognised in customer relationship management, the impact of these benefits on loyalty behaviours is yet to be investigated in the context of loyalty clubs. Little is known why some loyalty programmes outperform others. By using both qualitative and quantitative research approaches, this research developed and estimated a conceptual model that describes the interaction of key relational benefits and their contributions to customer loyalty in a set of milk formula customer clubs in China. Data were collected from 300 Chinese infant milk formula buyers, including both customer club members and nonmembers. This study confirms that the customer‐confidence benefits and identity‐related benefits precede other loyalty rewards and strengthen other loyalty incentives in a loyalty programme. The economic benefits and information‐sharing benefits play a mediating role and contribute directly to customer loyalty. The findings of this research help better understand the mechanism behind loyalty behaviours in customer clubs.
Design and Synthesis of a BODIPY‐Tetrazole Based “Off‐On” in‐Cell Fluorescence Reporter of Hydrogen Peroxide
Authors: An Peng , Lewandowski Tracey M. , Lin Qing
Published: January 2018

BODIPY‐linked bithiophene‐tetrazoles were designed and synthesized for bioorthogonal photoclick reactions in vitro and in vivo. The reactivity of these tetrazoles toward dimethyl fumarate was found to depend on the BODIPY attachment site, with the meta‐linked BODIPY–tetrazole being the most reactive. The resulting pyrazoline cycloadduct showed drastically reduced BODIPY fluorescence. However, BODIPY fluorescence recovered after treatment with hydrogen peroxide. This turn‐on effect was attributed to conversion from the pyrazoline to a pyrazole. Finally, we showed that this unique BODIPY–tetrazole off–on fluorescence probe can be used to detect hydrogen peroxide inside HeLa cells.
Application of SAR methods toward inhibition of bacterial peptidoglycan metabolizing enzymes
Authors: Tibaut Tjaša , Drgan Viktor , Novič Marjana
Published: January 2018

Structure activity relationship (SAR) methods are applied for a study of inhibition of peptidoglycan metabolizing enzymes, which could represent new antibacterial targets. In this study, we exploit experimental data of inhibition of Mur A and Mur B enzymes for classification of large set of chemicals. Based on inhibitory potency of compounds and their structures from the literature, we developed classification models for new, potential inhibitors of Mur A and Mur B enzymes. The best model for Mur A has the following performance measures for the validation set: 0.85, 0.75, and 0.80, for sensitivity, specificity, and normalized Matthews correlation coefficient, respectively. The same measures of the best Mur B model are 0.94, 0.75, and 0.86. Such models could represent valuable computational tools for theoretic predictions of compounds' activities against specific targets. Additionally, application of such models, like any other computational tools, significantly reduces time and costs in the early phase of drug design.
Modulator‐Controlled Synthesis of Microporous STA‐26, an Interpenetrated 8,3‐Connected Zirconium MOF with thethe‐iTopology, and its Reversible Lattice Shift
Authors: Bumstead Alice M. , Cordes David B. , Dawson Daniel M. , Chakarova Kristina K. , Mihaylov Mihail Y. , Hobday Claire L. , Düren Tina , Hadjiivanov Konstantin I. , Slawin Alexandra M. Z. , Ashbrook Sharon E. , Prasad Ram R. R. , Wright Paul A.
Published: January 2018

A fully interpenetrated 8,3‐connected zirconium MOF with thethe‐itopology type, STA‐26 (St Andrews porous material‐26), has been prepared using the 4,4′,4“‐(2,4,6‐trimethylbenzene‐1,3,5‐triyl)tribenzoate (TMTB) tritopic linker with formic acid as a modulating agent. In the as‐prepared form STA‐26 possessesImmsymmetry compared with thePmmsymmetry of the non‐interpenetrated analogue, NU‐1200, prepared using benzoic acid as a modulator. Upon removal of residual solvent there is a shift between the interpenetrating lattices and a resultant symmetry change toCmcmwhich is fully reversible. This is observed by X‐ray diffraction and13C MAS NMR is also found to be remarkably sensitive to the structural transition. Furthermore, heating STA‐26(Zr) in vacuum dehydroxylates the Zr6nodes leaving coordinatively unsaturated Zr4+sites, as shown by IR spectroscopy using CO and CD3CN as probe molecules. Nitrogen adsorption at 77 K together with grand canonical Monte Carlo simulations confirms a microporous, fully interpenetrated, structure with pore volume 0.53 cm3 g−1while CO2adsorption at 196 K reaches 300 cm3STP g−1at 1 bar. While the pore volume is smaller than that of its non‐interpenetrated mesoporous analogue, interpenetration makes the structure more stable to moisture adsorption and introduces shape selectivity in adsorption.
Anion Sensing by Fluorescent Expanded Calixpyrroles
Authors: Pushina Mariia , Koutnik Petr , Nishiyabu Ryuhei , Minami Tsuyoshi , Savechenkov Pavel , Anzenbacher Pavel
Published: January 2018

Expanded calixpyrrole‐type macrocycles, calix[2]benzo[4]pyrroles, bearing fluorescent moieties attached via conjugated vinyl spacers, have been synthesized from the corresponding formyl derivatives through Knoevenagel condensation. The anion‐binding properties of the resulting fluorescent macrocycles have been studied by means of NMR, UV/Vis, and fluorescence spectroscopies. Our main focus has been on dicarboxylates matching the size of the binding cavity of the calix[2]benzo[4]pyrrole skeleton. The observed anion‐binding properties were compared with those of the regular calix[4]pyrroles bearing identical fluorophores. Surprisingly, the parent calix[4]pyrroles appear to be equally efficient, if not more so, for sensing anions such as dicarboxylates. Affinity constants determined for various anions and dianions show the sensors S1–S5 to be highly cross‐reactive. The cross‐reactivity of the sensors was utilized in a microchip‐based array, which showed perfect (100 %) classification of 18 analytes utilizing only five sensors. Finally, the same array was used to quantitatively analyze dicarboxylates such as oxalate and malonate. The data from the array were subjected to linear regression, allowing the determination of various concentrations of dianions with low error (<2 %).
Nanoconfined Oxidation Synthesis of N‐Doped Carbon Hollow Spheres and MnO2 Encapsulated Sulfur Cathode for Superior Li‐S Batteries
Authors: Shen Jiadong , Liu Jun , Liu Zhengbo , Hu Renzong , Liu Jiangwen , Zhu Min
Published: January 2018

Invited for the cover of this issue is the group of Jun Liu at the South China University of Technology. The image depicts the complete synthetic route of S‐MnO2@C product and the excellent confined effect of rationally introduced carbon and MnO2 for the polysulfide. Read the full text of the article at 10.1002/chem.201704590.
Preparation of nano‐ZIF‐8 in methanol with high yield
Authors: Ta Don N. , Nguyen Hong K. D. , Trinh Bai X. , Le Quynh T. N. , Ta Hung N. , Nguyen Ha T.
Published: January 2018

This article systematically presented analysis results of factors affecting the preparation of nano‐ZIF‐8 in methanol for high yield. Samples were characterized by X‐ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR), Brunauer‐Emmett‐Teller (BET) adsorption, and thermogravimetry‐differential thermal analysis (TG/DTA). Synthesized nano‐ZIF‐8 had advantages over commercial ZIF‐8 (Basolite® Z1200 from Sigma‐Aldrich) such as a higher surface area, consisting of not only micropores like Basolite® Z1200 but also subordinate mesopores, formed by an assembly of nano‐ZIF‐8 crystals, which was 30 nm. Specifically, for the first time, nano‐ZIF‐8 was prepared in methanol with the yield of 61.2 %.
Automatic runtime calculation of communications for data‐parallel expressions with periodic conditions
Authors: Moreton‐Fernandez Ana , Gonzalez‐Escribano Arturo
Published: January 2018

Many real‐world applications feature data accesses on periodic domains. Manually implementing the synchronizations and communications associated to the data dependences on each case is cumbersome and error‐prone. It is increasingly interesting to support these applications in high‐level parallel programming languages or parallelizing compilers. In this paper, we present a technique that, for distributed‐memory systems, calculates the specific communications derived from data‐parallel codes with or without periodic boundary conditions on affine access expressions. It makes transparent to the programmer the management of aggregated communications for the chosen data partition. Our technique moves to runtime part of the compile‐time analysis typically used to generate the communication code for affine expressions, introducing a complete new technique that also supports the periodic boundary conditions. We present an experimental study to evaluate our proposal using several study cases. Our experimental results show that our approach can automatically obtain communication codes as efficient as those found in MPI reference codes, reducing the development effort.
Differentiation and Contractile Analysis of GFP‐Sarcomere Reporter hiPSC‐Cardiomyocytes
Authors: Sharma Arun , Toepfer Christopher N. , Schmid Manuel , Garfinkel Amanda C. , Seidman Christine E.
Published: January 2018

Human induced pluripotent stem cell‐derived cardiomyocytes (hiPSC‐CMs) represent a powerful cellular platform for illuminating mechanisms of human cardiovascular disease and for pharmacological screening. Recent advances in CRISPR/Cas9‐mediated genome editing technology underlie this profound utility. We have generated hiPSC‐CMs harboring fluorescently‐tagged sarcomeric proteins, which provide a tool to non‐invasively study human sarcomere function and dysfunction. In this unit, we illustrate methods for conducting high‐efficiency, small molecule‐mediated differentiation of hiPSCs into cardiomyocytes, and for performing non‐invasive contractile analysis through direct sarcomere tracking of GFP‐sarcomere reporter hiPSC‐CMs. We believe that this type of analysis can overcome sensitivity problems found in other forms of contractile assays involving hiPSC‐CMs by directly measuring contractility at the fundamental contractile unit of the hiPSC‐CM, the sarcomere. © 2018 by John Wiley & Sons, Inc.
An intelligent database proactive cache replacement policy for mobile communication system based on genetic programming
Authors: Darwish Saad M. , El‐Shnawy Amr G.
Published: January 2018

In the mobile environment, the movement of the users, disconnected modes, many data updates, power battery consumption, limited cache size, and limited bandwidth impose significant challenges in information access. Caching is considered one of the most important concepts to deal with these challenges. There are 2 general topics related to the client cache policy: cache invalidation method keeps data in the cache up to date and cache replacement method chooses the cached element(s) that would be removed from the cache once the cache stays full. The aim of this work is to introduce a new technique for cache replacement in a mobile database that takes into consideration the impact of invalidation time for enhancing data availability in the mobile environment by using genetic programming. In this case, each client collects information for every cached item in the cache like access probability, cached document size, and validation time and uses these factors in a fitness function to determine cached items that will be removed from the cache. The experiments were carried by NS2 simulator to assess the efficiency of the proposed method, and the outcomes are judged against existing cache replacement algorithms. It is concluded that the proposed approach performs significantly better than other approaches.
Selective extraction of high‐value phenolic compounds from distillation wastewater of basil (Ocimum basilicum L.) by pressurized liquid extraction
Authors: Pagano Imma , Sánchez‐Camargo Andrea del Pilar , Mendiola Jose Antonio , Campone Luca , Cifuentes Alejandro , Rastrelli Luca , Ibañez Elena
Published: January 2018

During the essential oil steam distillation from aromatic herbs, huge amounts of distillation wastewaters (DWWs) are generated. These by‐products represent an exceptionally rich source of phenolic compounds such as rosmarinic acid (RA) and caffeic acid (CA). Herein, the alternative use of dried basil DWWs (dDWWs) to perform a selective extraction of RA and CA by pressurized liquid extraction (PLE) employing bio‐based solvent was studied. To select the most suitable solvent for PLE, the theoretical modelling of Hansen solubility parameters (HSP) was carried out. This approach allows reducing the list of candidate to two solvents: ethanol and ethyl lactate. Due to the composition of the sample, mixtures of water with those solvents were also tested. An enriched PLE extract in RA (23.90 ± 2.06 mg/g extract) with an extraction efficiency of 75.89 ± 16.03% employing a water‐ethanol mixture 25:75 (% v/v) at 50°C was obtained. In the case of CA, a PLE extract with 2.42 ± 0.04 mg/g extract, having an extraction efficiency of 13.86 ± 4.96% using ethanol absolute at 50°C was achieved. DWWs are proposed as new promising sources of natural additives and/or functional ingredients for cosmetic, nutraceutical, and food applications.