bluuebunny/crossref_metadata_2025_split huggingface dataset:
Doping and Anisotropy–Dependent Electronic Transport in Chalcogenide Perovskite CaZrSe3 for High Thermoelectric Efficiency
Authors: Osei‐Agyemang Eric , Enninful Adu Challen , Balasubramanian Ganesh 
Published: July 2019

AbstractThe potential of an environmentally friendly and emerging chalcogenide perovskite CaZrSe3 for thermoelectric applications is examined. The orthorhombic phase of CaZrSe3 has an optimum band gap (1.35–1.40 eV) for single‐junction photovoltaic applications. The predictions reveal that CaZrSe3 possesses an absorption coefficient of ≈4 × 105 cm−1 at photon energies of 2.5 eV with an early onset of optical absorption (≈0.2 eV) well below the optimum band gap. Seebeck coefficient, S, is inversely proportional to the carrier mobility as the calculated average effective mass for electrons is higher than for holes; p‐type doping enhances the electrical conductivity, σ. The electronic thermal conductivity κe remains low at all temperatures. The upper limit of the thermoelectric figure of merit (ZTe) attains ≈1.0 when doped at specific chemical potentials, while a high Seebeck coefficient contributes to the ZTe = 1.95 at 50 K for p‐type doping with 1018 cm−3 carrier concentration, demonstrating high thermoelectric efficiency.
Pre‐eclampsia and long‐term cardiac dysfunction: A review of asymptomatic cardiac changes existing well beyond the post‐partum period
Authors: Thayaparan Archana S , Said Joanne M , Lowe Sandra A , McLean Anthony , Yang Yang 
Published: July 2019

AbstractBackgroundPre‐eclampsia is a disease of pregnancy characterised by the manifestations of multi‐organ dysfunction. The recent use of transthoracic echocardiography in the assessment of women with pre‐eclampsia has allowed the detection of cardiac systolic and diastolic dysfunction in the acute phase. Women with a history of pre‐eclampsia also have increased lifelong risks of cardiovascular disease and mortality that persists well beyond the post‐partum period. These developments raise the possibility that pre‐eclampsia may be an early marker of cardiovascular disease and the potential role for echocardiography in guiding the detection and management of this. This review aims to summarise the existing evidence of echocardiographic cardiac assessment of women with a history of pre‐eclampsia performed more than 12 weeks post‐partum.MethodsA systematic search of PubMed and OVID EMBASE databases was performed to identify studies featuring assessment of cardiac function performed after 12 weeks post‐partum in women with a history of pre‐eclampsia. Studies without post‐partum cardiac assessment or with other documented causes for cardiomyopathy were excluded.ResultsThirteen studies were identified that measured cardiac function by transthoracic echocardiography between 6 months and 18 years following a pregnancy complicated by pre‐eclampsia. Common findings across the studies were of increased diastolic dysfunction, increased left ventricular mass index (LVMI) and concentric hypertrophy in women with a history of pre‐eclampsia, as compared to women with uncomplicated pregnancy histories. This was predominantly seen in those with a history of early or preterm pre‐eclampsia.ConclusionsWomen with a history of early or preterm pre‐eclampsia have an increased prevalence of diastolic dysfunction. This review demonstrates that the cardiac dysfunction associated with previous pre‐eclampsia is quantifiable and persistent. Progression of heart failure from asymptomatic to symptomatic stages carries a fivefold increase in mortality. The use of echocardiography could detect cardiac dysfunction in the asymptomatic stage and guide more intensive risk factor modification in these women.
Die zentrale Rolle der Methodenentwicklung in der gerichteten Evolution selektiver Enzyme
Authors: Qu Ge , Li Aitao , Acevedo‐Rocha Carlos G. , Sun Zhoutong , Reetz Manfred T. 
Published: July 2019

AbstractDie gerichtete Evolution von stereo‐, regio‐ und chemoselektiven Enzymen ist ein einzigartiges Verfahren zur Herstellung von Biokatalysatoren für synthetisch interessante Transformationen. Methodenentwicklung war und bleibt unerlässlich, um diese Technik des Protein‐Engineerings effizient, schnell, zuverlässig und als relevant für die organische Chemie zu gestalten. Dieser Aufsatz widmet sich den jüngsten Entwicklungen auf diesem Gebiet, wobei frühe wichtige Beiträge ebenfalls Beachtung finden. Er schreibt die Optimierung molekularbiologischer Methoden zur Genmutagenese und Strategien für deren effizienten Einsatz, um so den Screeningaufwand (der Engpass in der gerichteten Evolution) möglichst gering zu halten. Im Hinblick auf die laborbasierte Evolution von Selektivität und Aktivität hat sich ergeben, dass fortgeschrittene Versionen von CAST (Combinatorial Active‐site Saturation Test) und iterativer Sättigungsmutagenese (ISM) als spezielle Formen der Sättigungsmutagenese (SM) an der Bindungstasche bevorzugt verwendet werden, unterstützt durch In‐silico‐Methoden wie Maschinellem Lernen. Die jüngst vorgeschlagene FRISM‐Technik (Focused Rational Iterative Site‐specific Mutagenesis) gilt als Fusion von rationalem Design und gerichteter Evolution. Die chemische Festphasensynthese von Genen auf einem Chip zum schnellen Bibliotheksaufbau vermeidet eine unerwünschte Präferenz spezifischer Aminosäuren und verbessert die Qualität von Substanzbibliotheken erheblich – ist dies die Zukunft der gerichteten Evolution?
Antwort auf den Kommentar zu “Stabilisierung eines niedrigvalenten Eisen(I)‐Ions in einem hochvalentem molekularen Vanadium(V) Oxid‐Cluster”
Authors: Anjass Montaha H. , Kastner Katharina , Nägele Florian , Ringenberg Mark , Boas John F. , Zhang Jie , Bond Alan , Jacob Timo , Streb Carsten 
Published: July 2019

AbstractDie Autoren der Zuschrift “Stabilisierung eines niedrigvalenten Eisen(I)‐Ions in einem hochvalentem molekularen Vanadium(V) Oxid‐Cluster” antworten auf ein Kommentar von Dr. Sproules, der eine alternative Interpretation der Metall‐Oxidationsstufen im Zwei‐Elektronen‐reduzierten Cluster (NH2Me2)[(FeCl)V12O32Cl]4− liefert.
De novo Design of Selective Membrane‐Active Peptides by Enzymatic Control of Their Conformational Bias on the Cell Surface
Authors: Shi Junfeng , Schneider Joel P. 
Published: July 2019

AbstractSelectively targeting the membrane‐perturbing potential of peptides towards a distinct cellular phenotype allows one to target distinct populations of cells. We report the de novo design of a new class of peptide whose ability to perturb cellular membranes is coupled to an enzyme‐mediated shift in the folding potential of the peptide into its bioactive conformation. Cells rich in negatively charged surface components that also highly express alkaline phosphatase, for example many cancers, are susceptible to the action of the peptide. The unfolded, inactive peptide is dephosphorylated, shifting its conformational bias towards cell‐surface‐induced folding to form a facially amphiphilic membrane‐active conformer. The fate of the peptide can be further tuned by peptide concentration to affect either lytic or cell‐penetrating properties, which are useful for selective drug delivery. This is a new design strategy to afford peptides that are selective in their membrane‐perturbing activity.
Infrared Spectroscopic Observation of a G–C+ Hoogsteen Base Pair in the DNA:TATA‐Box Binding Protein Complex Under Solution Conditions
Authors: Stelling Allison L. , Liu Amy Y. , Zeng Wenjie , Salinas Raul , Schumacher Maria A. , Al‐Hashimi Hashim M. 
Published: July 2019

AbstractHoogsteen DNA base pairs (bps) are an alternative base pairing to canonical Watson–Crick bps and are thought to play important biochemical roles. Hoogsteen bps have been reported in a handful of X‐ray structures of protein–DNA complexes. However, there are several examples of Hoogsteen bps in crystal structures that form Watson–Crick bps when examined under solution conditions. Furthermore, Hoogsteen bps can sometimes be difficult to resolve in DNA:protein complexes by X‐ray crystallography due to ambiguous electron density and by solution‐state NMR spectroscopy due to size limitations. Here, using infrared spectroscopy, we report the first direct solution‐state observation of a Hoogsteen (G–C+) bp in a DNA:protein complex under solution conditions with specific application to DNA‐bound TATA‐box binding protein. These results support a previous assignment of a G–C+ Hoogsteen bp in the complex, and indicate that Hoogsteen bps do indeed exist under solution conditions in DNA:protein complexes.
The Crucial Role of Methodology Development in Directed Evolution of Selective Enzymes
Authors: Qu Ge , Li Aitao , Acevedo‐Rocha Carlos G. , Sun Zhoutong , Reetz Manfred T. 
Published: July 2019

AbstractDirected evolution of stereo‐, regio‐, and chemoselective enzymes constitutes a unique way to generate biocatalysts for synthetically interesting transformations in organic chemistry and biotechnology. In order for this protein engineering technique to be efficient, fast, and reliable, and also of relevance to synthetic organic chemistry, methodology development was and still is necessary. Following a description of early key contributions, this review focuses on recent developments. It includes optimization of molecular biological methods for gene mutagenesis and the design of efficient strategies for their application, resulting in notable reduction of the screening effort (bottleneck of directed evolution). When aiming for laboratory evolution of selectivity and activity, second‐generation versions of Combinatorial Active‐Site Saturation Test (CAST) and Iterative Saturation Mutagenesis (ISM), both involving saturation mutagenesis (SM) at sites lining the binding pocket, have emerged as preferred approaches, aided by in silico methods such as machine learning. The recently proposed Focused Rational Iterative Site‐specific Mutagenesis (FRISM) constitutes a fusion of rational design and directed evolution. On‐chip solid‐phase chemical gene synthesis for rapid library construction enhances library quality notably by eliminating undesired amino acid bias, the future of directed evolution?
The negative feedback effects of sea surface temperatures on El Niño Events in the West Indian Ocean
Authors: Zhang Fuying , Zhang Gaojie , Liu Lei , Dong Lina 
Published: July 2019

AbstractIn this study, multiple sets of atmospheric and oceanic observational data were used in combination with composite analysis and correlation analysis methods, in order to analyze the anomalous eastward spread phenomena of the equatorial Indian Ocean during the autumn and winter seasons when El Niño events have previously occurred. The analysis results showed that anomalous increases in the SSTs (sea surface temperatures) in the West Indian Ocean during the early autumn seasons had triggered the responses of anomalous easterlies. Meanwhile, anomalous anticyclonic circulation was observed to have existed on the north side of the easterlies. It was found that with the maximum center of the specific humidity retreating toward the vicinity of the equator during the processes of the seasonal conversion, the asymmetry of moisture advection on the eastern and western sides of the anomalous anticyclonic circulations tended to lead to the circulation systems to move in an eastward direction until reaching the Northwest Pacific region. During the winter seasons with peak periods of El Niño events, the easterly anomalies in the equatorial West Pacific Ocean were found to stimulate the upturning Kelvin fluctuations in the ocean. This resulted in eastward spreading actions which eventually helped the El Niño events to transform into La Niña events.
Assessing changes in risk of amplified planetary waves in a warming world
Authors: Huntingford Chris , Mitchell Dann , Kornhuber Kai , Coumou Dim , Osprey Scott , Allen Myles 
Published: July 2019

AbstractSummer weather extremes are often associated with high‐amplitude atmospheric planetary waves (Petoukhov et al., 2013). Such conditions lead to stationary weather patterns, triggering heat waves and sometimes prolonged intense rainfall. These wave events, referred to as periods of Quasi‐Resonant Amplification (QRA), are relatively rare though and hence provide only a few data points in the meteorological record to analyse. Here, we use atmospheric models coupled to boundary conditions that have evolved slowly (i.e., climate), to supplement measurements. Specifically we assess altered probabilities of resonant episodes by employing a unique massive ensemble of atmosphere‐only climate simulations to populate statistical distributions of event occurrence. We focus on amplified waves during the two most extreme European heat waves on record, in years 2003 and 2015 (Russo et al., 2015). These years are compared with other modelled recent years (1987–2011), and critically against a modelled world without climate change. We find that there are differences in the statistical characteristics of wave event likelihood between years, suggesting a strong dependence on the known and prescribed Sea Surface Temperature (SST) patterns. The differences are larger than those projected to have occurred under climate change since the pre‐industrial period. However, this feature of small differences since pre‐industrial is based on single large ensembles, with members consisting of a range of estimates of SST adjustment from pre‐industrial to present. Such SST changes are from projections by a set of coupled atmosphere–ocean (AOGCM) climate models. When instead an ensemble for pre‐industrial estimates is subdivided into simulations according to which AOGCM the SST changes are based on, we find differences in QRA occurrence. These differences suggest that to reliably estimate changes to extremes associated with altered amplification of planetary waves, and under future raised greenhouse gas concentrations, likely requires reductions in any spread of future modelled SST patterns.
Clinical characteristics and prognostic value of pre‐retreatment plasma epstein‐barr virus DNA in locoregional recurrent nasopharyngeal carcinoma
Authors: Liu Ming‐Zhu , Fang Shuo‐Gui , Huang Wei , Wang Han‐Yu , Tian Yun‐Ming , Huang Run‐Da , Sun Zhuang , Zhao Chong , Lu Tai‐Xiang , Huang Ying , Han Fei 
Published: July 2019

AbstractPurposeTo define the clinical characteristics and prognostic value of pre‐retreatment plasma Epstein‐Barr virus (EBV) DNA, we investigated EBV status in locoregional recurrent nasopharyngeal carcinoma (lrNPC) patients.MethodsBetween April 2008 and August 2016, the data of patients with nonmetastatic lrNPC were retrospectively reviewed. The survival indexes of patients between different pre‐retreatment EBV status groups were compared.ResultsA total of 401 patients with nonmetastatic lrNPC were enrolled, and 197 (49.1%) patients had detectable pre‐retreatment plasma EBV DNA. Treatment included radiotherapy alone (n = 37 patients), surgery alone (n = 105), radiotherapy (n = 208), surgery combined with radiotherapy (n = 20), chemotherapy and targeted therapy (n = 31). Median follow‐up was 32 months. The 3‐year locoregional relapse‐free survival (LRRFS), distant metastasis‐free survival (DMFS), and overall survival (OS) rates for the entire cohort were 64.8%, 89.4%, and 58.8%, respectively. The estimated 3‐year LRRFS, DMFS, and OS rates for the pre EBV‐positive group vs the pre EBV‐negative group were 54.2% vs 75.0% (P < 0.001), 86.6% vs 91.9% (P = 0.05), 51.6% vs 65.9% (P = 0.01), respectively. Among patients in the clinical stage rI/II, there were 17 patients in the radiotherapy alone group and 49 patients in the surgery alone group. And there was no significant difference in overall survival between radiotherapy and surgery, even among the different pre‐EBV statuses (P > 0.05). In terms of long‐term toxic and side effects, the incidence of radioactive temporal lobe injury in the radiotherapy group was higher than that in the surgery group (35.3% vs 8.2%, P < 0.001), and no statistically significant difference was found in other long‐term toxic and side effects.ConclusionsThe positive rate of pre‐retreatment plasma EBV DNA in lrNPC is lower than primary NPC. The prognosis of EBV DNA negative group is better than positive group. For locally early‐stage lrNPC, regardless of EBV DNA status, radiotherapy and surgery are available options and both can achieve better long‐term survival.
Protein Chemical Synthesis Combined with Mirror‐Image Phage Display Yields d‐Peptide EGF Ligands that Block the EGF–EGFR Interaction
Authors: Díaz‐Perlas Cristina , Varese Monica , Guardiola Salvador , Sánchez‐Navarro Macarena , García Jesús , Teixidó Meritxell , Giralt Ernest 
Published: July 2019

AbstractThe epidermal growth factor (EGF) pathway, being overactive in a number of cancers, is a good target for clinical therapy. Although several drugs targeting the EGF receptor (EGFR) are on the market, tumours acquire resistance very rapidly. As an alternative, small molecules and peptides targeting EGF have been developed, although with moderate success. Herein, we report the use of mirror‐image phage display technology to discover protease‐resistant peptides with the capacity to inhibit the EGF–EGFR interaction. After the chemical synthesis of the enantiomeric protein d‐EGF, two phage‐display peptide libraries were used to select binding sequences. The d versions of these peptides bound to natural EGF, as confirmed by surface acoustic waves (SAWs). High‐field NMR spectroscopy showed that the best EGF binder, d‐PI_4, interacts preferentially with an EGF region that partially overlaps with the receptor binding interface. Importantly, we also show that d‐PI_4 efficiently disrupts the EGF–EGFR interaction. This methodology represents a straightforward approach to find new protease‐resistant peptides with potential applications in cancer therapy.
Chemical‐Labeling‐Assisted Detection of Nucleobase Modifications by Quantum‐Tunneling‐Based Single‐Molecule Sensing
Authors: Furuhata Takafumi , Ohshiro Takahito , Izuhara Yuichi , Suzuki Tomoaki , Ueki Ryosuke , Taniguchi Masateru , Sando Shinsuke 
Published: July 2019

AbstractQuantum‐tunneling‐based DNA sensing is a single‐molecule technique that promises direct mapping of nucleobase modifications. However, its applicability is seriously limited because of the small difference in conductivity between modified and unmodified nucleobases. Herein, a chemical labeling strategy is presented that facilitates the detection of modified nucleotides by quantum tunneling. We used 5‐Formyl‐2′‐deoxyuridine as a model compound and demonstrated that chemical labeling dramatically alters its molecular conductance compared with that of canonical nucleotides; thus, facilitating statistical discrimination, which is impeded in the unlabeled state. This work introduces a chemical strategy that overcomes the intrinsic difficulty in quantum‐tunneling‐based modification analysis—the similarity of the molecular conductance of the nucleobases of interest.
Photocatalytic Synthesis of p‐Anisaldehyde in a Mini Slurry‐Bubble Reactor under Solar Light Irradiation
Authors: Heggo Dalia , Ookawara Shinichi , Ohno Teruhisa , Nakai Toru , Matsushita Yoshihisa , Eldin Mona Gamal , Ohshima Masahiro 
Published: July 2019

Dense photocatalyst slurry was employed for the synthesis of p‐anisaldehyde under solar light irradiation. An Fe‐modified rutile TiO
2 (Fe‐TiO
2, 34.5 m
2/g) photocatalyst was used as a visible‐light‐responsive photocatalyst. A conventional TiO
2 (P25, 35 m
2/g) photocatalyst was also examined as a reference catalyst. XRD patterns and diffuse reflectance spectra showed that Fe‐TiO
2 consists of 100 % rutile phase and absorbs more visible light compared to P25, respectively. The catalyst powder was suspended in an ethyl acetate solution of p‐methoxytoluene in the mini‐reactor, with oxygen bubbling, under a solar simulator, visible light, and UV LEDs. p‐anisaldehyde, as a reaction product, was analyzed by sampling using gas‐chromatograph. Regardless of the light source, Fe‐TiO
2 always outperformed P25 in terms of both generation rates (GR) of p‐anisaldehyde and energy requirements (ER). It was demonstrated that the highly dense Fe‐TiO
2 slurry was efficient for the synthesis under solar light owing to the small size of the reactor. The small amount of Pt and ZrO
2 cocatalysts significantly enhanced the GR under solar light. By adopting a visible light responsive Fe‐TiO
2 photocatalyst, the mini slurry‐bubble reactor under solar light achieved a high GR per catalyst mass (CM), which is one to two orders higher than that reported by most previous studies with high‐power lamps.
A Randomized, Placebo‐Controlled Trial to Assess the Effects of 8 Weeks of Administration of GSK256073, a Selective GPR109A Agonist, on High‐Density Lipoprotein Cholesterol in Subjects With Dyslipidemia
Authors: Olson Eric J. , Mahar Kelly M. , Haws Thomas F. , Fossler Michael J. , Gao Feng , de Gouville Anne‐Charlotte , Sprecher Dennis L. , Lepore John J. 
Published: July 2019

AbstractGPR109A (HM74A), a G‐protein‐coupled receptor, is hypothesized to mediate lipid and lipoprotein changes and dermal flushing associated with niacin administration. GSK256073 (8‐chloro‐3‐pentyl‐1H‐purine‐2,6[3H,7H]‐dione) is a selective GPR109A agonist shown to suppress fatty acid levels and produce mild flushing in short‐term clinical studies. This study evaluated the effects of GSK256073 on lipids in subjects with low high‐density lipoprotein cholesterol (HDLc). Subjects (n = 80) were randomized (1:1:1:1) to receive GSK256073 5, 50, or 150 mg/day or matching placebo for 8 weeks. The primary end point was determining the GSK256073 exposure‐response relationship for change from baseline in HDLc. No significant exposure response was observed between GSK256073 and HDLc levels. GSK256073 did not significantly alter HDLc levels versus placebo, but rather revealed a trend at the 150‐mg dose for a nonsignificant decrease in HDLc (‐6.31%; P = .12) and an increase in triglycerides (median, 24.4%; 95% confidence interval, 7.3%‐41.6%). Flushing was reported in 21%, 25%, and 60% of subjects (5, 50, and 150 mg, respectively) versus 24% for placebo. Results indicated that selective activation of the GPR109A receptor with GSK256073 did not produce niacin‐like lipid effects. These findings add to the increasing evidence that niacin‐mediated lipoprotein changes occur predominantly via GPR109A‐independent pathways.
Early emergence increases survival of tree seedlings in Central European temperate forests despite severe late frost
Authors: Bianchi Eva , Bugmann Harald , Bigler Christof 
Published: July 2019

AbstractGlobal warming is expected to result in earlier emergence of tree seedlings that may experience higher damages and mortality due to late frost in spring. We monitored emergence, characteristics, and survival of seedlings across ten tree species in temperate mixed deciduous forests of Central Europe over one and a half year. We tested whether the timing of emergence represents a trade‐off for seedling survival between minimizing frost risk and maximizing the length of the growing period. Almost two‐thirds of the seedlings died during the first growing period. The timing of emergence was decisive for seedling survival. Although seedlings that emerged early faced a severe late frost event, they benefited from a longer growing period resulting in increased overall survival. Larger seedling height and higher number of leaves positively influenced survival. Seedlings growing on moss had higher survival compared to mineral soil, litter, or herbaceous vegetation. Synthesis. Our findings demonstrate the importance of emergence time for survival of tree seedlings, with early‐emerging seedlings more likely surviving the first growing period.