bluuebunny/crossref_metadata_2025 huggingface dataset:
Site selection by geese in a suburban landscape
Authors: Groom Quentin J , Adriaens Tim , Colsoulle Claire , Delhez Pauline , Van Der Beeten Iris
Published: May 2019

Background

In northern European and North American cities geese are one of the commonest and most visible large herbivores that inhabit the suburban environment . As such, their presence and behavior often conflicts with the desires of the human residents. Fouling, noise, aggression and health concerns are all cited as reasons that there are “too many”. Lethal control is often used for control, however, this raises questions about whether this is a sustainable strategy to resolve the conflict between humans and geese, when paradoxically, it is humans that are responsible for creating the habitat and often providing the food and protection of geese at other times. We hypothesis that the landscaping of suburban parks can be improved to decrease its attractiveness to geese and to reduce the opportunity for conflict between geese and humans.

Methods.

Using observations collected over five years from a botanic garden situated in suburban Belgium and data from the whole of Flanders in Belgium we examine landscape features that attract geese, including the presence of islands in lakes, the distance from water, barriers to level flight and the size of grazing areas. The birds studied were the tadornine goose Alopochen aegyptiaca (L. 1766) (Egyptian geese) and the anserine geese, Branta canadensis (L. 1758) (Canada geese), Anser anser (L. 1758) (greylag geese) and Branta leucopsis (Bechstein, 1803) (barnacle geese). Landscape modification is a known method for modifying geese behavior, but there is little information on the power of such methods with which to inform managers and planners.

Results.

Our results demonstrate that lakes with islands attract more than twice as many anserine geese, than lakes without island, but make little difference to Egyptian geese. Furthermore, flight barriers between grazing areas and lakes are an effective deterrent to geese using an area for feeding. Keeping grazing areas small and surrounded by trees reduces their attractiveness to geese.

Conclusion.

The results suggest that landscape design can be used successfully to reduce the number of geese and their conflict with humans. However, this approach has its limitations and would require humans to compromise on what they expect from their landscaped parks, such as open vistas, lakes and closely cropped lawns.
Risk of phosphorus loss in surface runoff from agricultural land in the Baltic Commune of Puck
Authors: Pietrzak Stefan , Pazikowska-Sapota Grażyna , Dembska Grażyna , Dzierzbicka-Glowacka Lidia Anita , Juszkowska Dominika , Majewska Zuzanna , Urbaniak Marek , Ostrowska Dominika , Cichowska Agnieszka , Galer-Tatarowicz Katarzyna
Published: May 2019

Background. Risk assessment of Phosphorus (P) losses in surface runoff from agricultural land is the basic measure that should be used as a part of actions taken to counteract the water eutrophication in watercourses and water reservoirs. To assess this risk, a new method has been recently developed based on the determination of degree of P saturation (DPS) which depends on P content in soil determined with the use of distilled water (water-soluble P – WSP).

Methods. Based on DPS method, the risk of P losses in surface runoff from agricultural land in Puck Commune (Baltic Sea Coast) was assessed and a critical analysis of assessment results was carried out. The research was conducted on mineral and organic soils from 50 and 11 separate agricultural plots with a total area of 133.82 and 37.23 ha, respectively. In collected soil samples, P content was determined using distilled water (all soil samples), Egner-Riehm method (mineral soils) and extract of 0.5 mol HCl ∙ dm-3 (organic soils). The results of determinations P content in water extract from soils were converted to DPS values, which were classified by appropriate limit intervals.

Results & Discussion. It was found that on 96.7% of tested agricultural parcels (96% plots with mineral soils and 100% plots with organic soils) there was a potentially high risk of P losses from soil by surface runoff. At the same time, it was ascertained that in soils from 62% of agricultural plots, there was a large deficiency of plant available P. Due to the above, as well as due to the lack of connection with other factors affecting the P losses in surface runoff such as type of crop and area inclination, it was considered that the assessment based on the DPS index may be unreliable.
Level of Agreement with the Microscopic Analysis of Joint Aspirate for the Diagnosis of Gout in the Lower Extremity
Authors: Zavisanos Alexis , Hasenstein Todd , Meyr Andrew J.
Published: May 2019

Background

Although clinical findings, laboratory serum markers, and radiographic images are also used, the purported gold standard or standard reference test for the diagnosis of gout is microscopic analysis of aspirated joint fluid. This observational investigation sought to identify the level of agreement with the microscopic analysis of joint fluid aspirate for the diagnosis of gout in the lower extremity between two departments in a single health-care center.

Methods

A retrospective medical record review identified consecutive patients seen for suspected gout who underwent diagnostic joint aspiration. Patients were included if a lower-extremity joint synovial fluid sample was obtained and were excluded if they were not independently evaluated by both the departments of rheumatology and pathology. We categorized the documented joint fluid findings into four groups: no crystals, sodium urate crystals, calcium pyrophosphate dihydrate crystals, or both sodium urate and calcium pyrophosphate dihydrate crystals. We defined a “clinically significant disagreement” as one department observing any type of crystals and the other department observing no crystals.

Results

We observed a clinically significant disagreement rate of 23.26% (intraclass correlation coefficient = 0.496). The department of rheumatology was more likely to observe the presence of crystals in a sample compared with the department of pathology (88.37% versus 65.12%; P = .02).

Conclusions

These results provide evidence that microscopic analysis of joint fluid aspirate might lack the accuracy and reliability needed to be considered a gold standard diagnostic test for gout in the lower extremity.
The ion channel ppk301 controls freshwater egg-laying in the mosquito Aedes aegypti
Authors: Matthews Benjamin J , Younger Meg A , Vosshall Leslie B
Published: May 2019

Female Aedes aegypti mosquitoes are deadly vectors of arboviral pathogens and breed in containers of freshwater associated with human habitation. Because high salinity is lethal to offspring, correctly evaluating water purity is a crucial parenting decision. We found that the DEG/ENaC channel ppk301 and sensory neurons expressing ppk301 control egg-laying initiation and choice in Ae. aegypti. Using calcium imaging, we found that ppk301-expressing cells show ppk301-dependent responses to water but, unexpectedly, also respond to salt in a ppk301-independent fashion. This suggests that ppk301 is instructive for egg-laying at low-salt concentrations, but that a ppk301-independent pathway is responsible for inhibiting egg-laying at high-salt concentrations. Water is a key resource for insect survival and understanding how mosquitoes interact with water to control different behaviors is an opportunity to study the evolution of chemosensory systems.
Ventral hippocampal projections to the medial prefrontal cortex regulate social memory
Authors: Phillips Mary L , Robinson Holly Anne , Pozzo-Miller Lucas
Published: May 2019

Inputs from the ventral hippocampus (vHIP) to the medial prefrontal cortex (mPFC) are implicated in several neuropsychiatric disorders. Here, we show that the vHIP-mPFC projection is hyperactive in the Mecp2 knockout mouse model of the autism spectrum disorder Rett syndrome, which has deficits in social memory. Long-term excitation of mPFC-projecting vHIP neurons in wild-type mice impaired social memory, whereas their long-term inhibition in Rett mice rescued social memory deficits. The extent of social memory improvement was negatively correlated with vHIP-evoked responses in mPFC slices, on a mouse-per-mouse basis. Acute manipulations of the vHIP-mPFC projection affected social memory in a region and behavior selective manner, suggesting that proper vHIP-mPFC signaling is necessary to recall social memories. In addition, we identified an altered pattern of vHIP innervation of mPFC neurons, and increased synaptic strength of vHIP inputs onto layer five pyramidal neurons as contributing factors of aberrant vHIP-mPFC signaling in Rett mice.
Flies spring a surprise
Authors: Kobler Johanna M , Grunwald Kadow Ilona C
Published: May 2019

A combination of genetic, anatomical and physiological techniques has revealed that the lateral horn, a region of the brain involved in olfaction in flies, has many more types of neurons than expected.
Purification of plant-derived anti-virus mAb through optimized pH conditions for coupling between protein A and epoxy-activated beads
Authors: Song Ilchan , Kang Yang Joo , Choi Su-Lim , Han Dalmuri , Kim Deuk-Su , Lee Hae Kyung , Lee Joon-Chul , Park Jeanho , Kim Do-Sun , Ko Kisung
Published: May 2019

The main goal of this research was to determine optimum pH conditions for coupling between protein A and epoxy-activated Sepharose beads for purification of monoclonal antibodies (mAbs) expressed in plants. To confirm the effect of pH conditions on purification efficacy, epoxy-activated agarose beads were coupled to protein A under the pH conditions of 8.5, 9.5, 10.5, and 11.5 (8.5R, 9.5R, 10.5R, and 11.5R, respectively). A total of 300 g of fresh leaf tissue of transgenic Arabidopsis expressing human anti-rabies mAb (mAbP) SO57 were harvested to isolate the total soluble protein (TSP). An equal amount of TSP solution was applied to five resin groups including commercial protein A resin (GR) as a positive control. The modified 8.5R, 9.5R, 10.5R, and 11.5R showed delayed elution timing compared to the GR control resin. Nano-drop analysis showed that the total amount of purified mAbPSO57 mAbs from 60 g of fresh leaf mass were not significantly different among 8.5R (400 μg), 9.5R (360 μg), 10.5R (380 μg), and GR (350 μg). The 11.5R (25 μg) had the least mAbPSO57. SDS–PAGE analysis showed that the purity of mAbPSO57 was not significantly different among the five groups. Rapid fluorescent focus inhibition tests revealed that virus-neutralizing efficacies of purified mAbPSO57 from all the five different resins including the positive control resin were similar. Taken together, both pH 8.5 and 10.5 coupling conditions with high recovery rate should be optimized for purification of mAbPSO57 from transgenic Arabidopsis plant, which will eventually reduce down-stream cost required for mAb production using the plant system.
Enzyme characterization and biological activities of a resuscitation promoting factor from an oil degrading bacterium Rhodococcus erythropolis KB1
Authors: Luo Dan , Chen Jixiang , Xie Gang , Yue Liang , Wang Yonggang
Published: May 2019

Resuscitation-promoting factors (Rpf) are a class of muralytic enzymes, which participate in recovery of dormant cells and promoting bacteria growth in poor media. In the present study the expression vector of the rpf-1 gene from an oil-degrading bacterium Rhodococcus erythropolis KB1 was constructed and expressed in Escherichia coli. The expressed protein was purified by Ni2+-affinity chromatography, and showed muralytic activity when measured with 4-methylumbelliferyl-β-D-N,N′,N″-triacetyl chitotrioside as substrate. Addition of purified Rpf-1 to R. erythropolis culture efficiently improved bacterial cell growth. The purified protein also increased resuscitation of viable but nonculturable cells of R. erythropolis to culturable state. The conserved amino acid residues including Asp45, Glu51, Cys50, Thr60, Gln69, Thr74, Trp75 and Cys114 of the Rpf-1 were replaced with different amino acids. The mutant proteins were also expressed and purified with Ni2+-affinity chromatography. The muralytic activities of the mutant proteins decreased to different extents when compared with that of the wild type Rpf-1. Gln69 was found to play the most important role in the enzyme activity, substitution of Gln69 with lysine (Q69K) resulted in the greatest decrease of muralytic activity. The other amino acid residues such as Asp45, Glu51, Cys50 and Cys114 were also found to be very important in maintaining muralytic activity and biological function of the Rpf-1. Our results indicated that Rpf-1 from R. erythropolis showed muralytic activities and weak protease activity, but the muralytic activity was responsible for its growth promotion and resuscitation activity.
Effect of Rural-Urban Migration on Food Security of Rural Households in Kwande Local Government Area of Benue State
Authors: Lordaah Sedoo , Solomon Agba , Solomon Nwafor
Published: May 2019

This study investigated the effect of rural-urban migration on food security of rural households in Kwande local government area of Benue State, Nigeria. Using multistage sampling technique and a semi-structured questionnaire as instrument, data for the study was collected from a sample of three hundred and eighty four (389) rural dwellers in the state. The study revealed the major causes and determined the effect of rural-urban migration of the food security of Kwande local government area and suggested measures to reduce the rate of rural-urban migration. Given that the F- statistics of 98.094 is significant at 1% level of significance, it implies that the computed F- value was higher than the F-tabulated value of (1.94) at 5% level of significance and (2.51) at 1% level of significance. Therefore, and the alternative hypothesis which states that factors such as search for job, quest for skill acquisition, search foe better education, quest for marriage, insecurity, social amenities, and natural disasters are the determining factors of rural urban migration was accepted. Therefore, the study concluded that reduction rural-urban migration and improvement in food security are dependent on these factors. Based on the effects of rural-urban migration, it was recommended that government/policy makers come up with policies that would lead to increased rural development and farm mechanization.
Programmable Granular Metamaterials for Reusable Energy Absorption
Authors: Fu Kangjia , Zhao Zhihua , Jin Lihua
Published: May 2019

Designing metamaterials with programmable features has emerged as a promising pathway for reusable energy absorption. While the current designs of reusable energy absorbers mainly exploit mechanical instability of flexible beams, here is created a new kind of metamaterial for reusable and programmable energy absorption by integrating rigid granular materials and compliant stretchable components. In each unit cell of the metamaterial, the stretchable components connect the granular particles to maintain the integrity and control the deformation pattern of the material. When the metamaterial is subjected to an external load, the input energy is partially trapped as elastic energy in the stretchable components, and partially dissipated by friction between the granular particles, forming hysteresis between the loading and unloading force–displacement curves. Through tuning the structural design of the metamaterial, the pretension and stiffness of the stretchable components, and the size of and friction between the particles, a vast design space is achieved to program the mechanical behavior of the metamaterial, such as the load–displacement curve, the multistability, and the amount of energy dissipation. Experimental impact tests on a thin glass panel confirm energy‐absorbing capability of the proposed metamaterial. This design strategy opens a new avenue for creating reusable energy‐absorbing metamaterials.
Linkage Groups within Thiol–Ene Photoclickable PEG Hydrogels Control In Vivo Stability
Authors: Hunckler Michael D. , Medina Juan D. , Coronel Maria M. , Weaver Jessica D. , Stabler Cherie L. , García Andrés J.
Published: May 2019

Thiol–norbornene (thiol–ene) photoclickable poly(ethylene glycol) (PEG) hydrogels are a versatile biomaterial for cell encapsulation, drug delivery, and regenerative medicine. Numerous in vitro studies with these 4‐arm ester‐linked PEG‐norbornene (PEG‐4eNB) hydrogels demonstrate robust cytocompatibility and ability to retain long‐term integrity with nondegradable crosslinkers. However, when transplanted in vivo into the subcutaneous or intraperitoneal space, these PEG‐4eNB hydrogels with nondegradable crosslinkers rapidly degrade within 24 h. This characteristic limits the usefulness of PEG‐4eNB hydrogels in biomedical applications. Replacing the ester linkage with an amide linkage (PEG‐4aNB) mitigates this rapid in vivo degradation, and the PEG‐4aNB hydrogels maintain long‐term in vivo stability for months. Furthermore, when compared to PEG‐4eNB, the PEG‐4aNB hydrogels demonstrate equivalent mechanical properties, crosslinking kinetics, and high cytocompatibility with rat islets and human mesenchymal stem cells. Thus, the PEG‐4aNB hydrogels may be a suitable replacement platform without necessitating critical design changes or sacrificing key properties relevant to the well‐established PEG‐4eNB hydrogels.
Interconnected Toroidal Hydrogels for Islet Encapsulation
Authors: Ernst Alexander U. , Wang Long‐Hai , Ma Minglin
Published: May 2019

Islet encapsulation and transplantation promises to improve upon current treatments for type 1 diabetes mellitus, though several limitations remain. Macroscale devices have been designed for in vivo transplantation and retrieval, but traditional geometries do not support clinically adequate mass transfer of nutrients to and insulin from the encapsulated tissue. Microcapsule technologies have improved mass transfer properties, but their clinical translation remains challenging as their complete retrieval is difficult, should the graft become a safety concern. Here, the design, characterization and testing of a novel encapsulation structure, comprised of elastomer‐reinforced interconnected toroidal hydrogels is reported. These donut‐shaped hydrogels feature a high surface area, higher than conventional spherical capsules of the same volume, bestowing suitable mass transport conditions, while allowing interconnection and reversible deformation for intraperitoneal implantation and retrieval. Diabetes correction up to 12 weeks and complete retrieval is achieved in a diabetic mouse model, providing a proof‐of‐concept for the potential application as a type 1 diabetes cell replacement therapy.
Multifunctional Nanohybrid of Palladium Nanoparticles Encapsulated by Carbon‐Dots for Exploiting Synergetic Applications
Authors: Dhenadhayalan Namasivayam , Hsin Tzu‐Han , Lin King‐Chuen
Published: May 2019

Palladium nanoparticles encapsulated in the carbon dots (Pd/C‐dots) are demonstrated to play a role of multifunctional nanohybrid in the synergetic applications of sensor and catalysis. The photochemical method is applied to synthesize Pd/C‐dots in which Pd nanoparticles (NPs) are dispersedly encapsulated by C‐dots layer. The nanohybrid can function as a fluorescent sensor and reductive catalyst, due to the inherent properties of C‐dots and Pd NPs, respectively. The Pd/C‐dots exhibit a highly selective and sensitive detection toward the nickel (Ni2+) ion with a detection limit of 7.26 × 10−9 m. Moreover, the Ni2+ is detected in MCF‐7 live cells signifying the applicability of nanohybrid as a promising sensor. On the other hand, the Pd/C‐dots show an excellent catalytic performance in the reduction of 4‐nitrophenol and eosin yellow. A plausible mechanism for sensing and catalysis behavior is proposed. The sensor system is designed on the basis of the fluorescence turn‐on when Ni2+ interacts with functional groups of the C‐dots layer. The activities of catalytic reduction are mainly governed by the Pd NPs and further enhanced when the C‐dots layer is incorporated. The Pd/C‐dots can serve as a new paradigm for opening a potential trend in the design of multifunctional materials to diverse applications.
Optical Metasurfaces: Evolving from Passive to Adaptive
Authors: Hail Claudio U. , Michel Ann‐Katrin U. , Poulikakos Dimos , Eghlidi Hadi
Published: May 2019

Optical metasurfaces are nanoengineered architectures aiming at the functional control of light propagation. In recent years, the performance of metasurfaces has been significantly improved and with the availability of such 2D metamaterials, different optical elements, such as flat achromatic lenses or compact spectrometers have been demonstrated. However, to a large extent, such demonstrations have focused on the realization of entirely passive (nonadaptive) metasurface properties. Adaptivity and active tuning of the optical function of a metasurface after fabrication is highly desirable, because it enables a host of more advanced applications such as beam scanning and dynamic holographic displays. Here, the evolution of the state of the art of metasurfaces toward attaining the adaptivity property and the resulting active control over the wavefront of light is reviewed. Starting from an overview of passive metasurfaces, the different approaches targeting adaptive metasurfaces are discussed, concluding with identifying crucial challenges and opportunities in this future‐oriented field.
Edge Effect on the Population of Free Carriers and Excitons in Single‐Crystal CH3NH3PbBr3 Perovskite Nanomaterials
Authors: Zhang Zhen‐Yu , Yu Kuai , Wang Guo‐Ping
Published: May 2019

The spatial distribution of free carriers and excitons in perovskite micro‐/nanostructures is currently a major topic of debate. They have been reported to coexist with spatial separation in individual perovskite grains and films. It is revealed that free carriers and excitons in single‐crystal CH3NH3PbBr3 perovskite microplatelets can spatially overlap; however, the distribution is such that the edges can be entirely occupied by the former, while the interior is occupied only by the latter. This is further confirmed in single‐crystal CH3NH3PbBr3 perovskite microstrips, in which only free carriers are observed. These results may be attributable to electrostatic potential fluctuations on the edges, which can promote electron–hole separation so that they do not bind to form excitons. Microscopic I–V measurements demonstrate that the microplatelet edges and the microstrips show current densities of more than 260 and 340 A cm−2 in a dark environment under 1.2 V bias voltage, respectively. It is suggested that these findings mean that such microstructures hold promise for the development of novel perovskite micro‐/nanostructure‐based optoelectronic devices with interesting photoconductive properties such as high photoluminescence intensity, longer excited‐state lifetime, high conductivity, large saturation current densities, and suppressed hysteresis effects (smaller open voltages).
Patterned Wettability Surface for Competition‐Driving Large‐Grained Perovskite Solar Cells
Authors: Wang Yang , Li Mingzhu , Li Huizeng , Lan Yangjie , Zhou Xue , Li Chang , Hu Xiaotian , Song Yanlin
Published: May 2019

Novel photovoltaic perovskite solar cells (PSCs) with high‐efficient photovoltaic property are largely in thrall to the uncertain perovskite grain size and inevitable defects. Here, inspired by the competitive growth between tree and grass in the forest system, a competitive perovskite grain growth approach via micro‐contact print (MicroCP) method (CD disk as templates) for printing wettability‐patterned substrate is proposed, aiming to achieve large‐grained perovskite and avoid discontinuous perovskite films caused by the low wettability of substrates. A MicroCP process is employed to construct a patterned wettability surface for the perovskite competitive growth mechanism on the electrode surface. This approach modifies the substrates quickly, ensures the uniform coverage of perovskite due to the function of ‐NH2 and Pb2+ bonds, and converts the perovskite films composed of small grains and pinholes into high‐quality perovskite films, free from pinholes and made up of large grains, resulting in efficiencies over 20% for the MicroCP PSCs.
Feedback With Performance Metric Scorecards Improves Resident Satisfaction but Does Not Impact Clinical Performance
Authors: Mamtani Mira , Shofer Frances S. , Sackeim Alexander , Conlon Lauren , Scott Kevin , Mills Angela M.
Published: May 2019

Objectives

The Emergency Medicine Milestone Project, a framework for assessing competencies, has been used as a method of providing focused resident feedback. However, the emergency medicine milestones do not include specific objective data about resident clinical efficiency and productivity, and studies have shown that milestone‐based feedback does not improve resident satisfaction with the feedback process. We examined whether providing performance metric reports to resident physicians improves their satisfaction with the feedback process and their clinical performance.

Methods

We conducted a three‐phase stepped‐wedge randomized pilot study of emergency medicine residents at a single, urban academic site. In phase 1, all residents received traditional feedback; in phase 2, residents were randomized to receive traditional feedback (control group) or traditional feedback with performance metric reports (intervention group); and in phase 3, all residents received monthly performance metric reports and traditional feedback. To assess resident satisfaction with the feedback process, surveys using 6‐point Likert scales were administered at each study phase and analyzed using two‐sample t‐tests. Analysis of variance in repeated measures was performed to compare impact of feedback on resident clinical performance, specifically patient treatment time (PTT) and patient visits per hour.

Results

Forty‐one residents participated in the trial of which 21 were randomized to the intervention group and 20 in the control group. Ninety percent of residents liked receiving the report and 74% believed that it better prepared them for expectations of becoming an attending physician. Additionally, residents randomized to the intervention group reported higher satisfaction (p = 0.01) with the quality of the feedback compared to residents in the control group. However, receiving performance metric reports, regardless of study phase or postgraduate year status, did not affect clinical performance, specifically PTT (183 minutes vs. 177 minutes, p = 0.34) or patients visits per hour (0.99 vs. 1.04, p = 0.46).

Conclusions

While feedback with performance metric reports did not improve resident clinical performance, resident physicians were more satisfied with the feedback process, and a majority of residents expressed liking the reports and felt that it better prepared them to become attending physicians. Residency training programs could consider augmenting feedback with performance metric reports to aide in the transition from resident to attending physician.
Mechanische Aktivierung beschleunigt die Hydrolyse der Amidbindung drastisch, vergleichbar der Aktivität von Enzymen
Authors: Pill Michael F. , East Allan L. L. , Marx Dominik , Beyer Martin K. , Clausen‐Schaumann Hauke
Published: May 2019

Peptidbindungen verbinden Aminosäuren in Proteinen und Polypeptiden. Sie zählen zu den Amidbindungen, die Proteinen und synthetischen Polyamiden ihre enorme Stärke verleihen. Obwohl Proteine und Polyamide in Natur und Technik mechanischen Kräften ausgesetzt sind, ist der Einfluss der Kraft auf die Stabilität der Amid‐ und Peptidbindung noch weitgehend unbekannt. Mittels Einzelmolekülkraftspektroskopie entdeckten wir, dass Kräfte von nur einigen hundert pN die Amidhydrolyse 109‐fach beschleunigen, was bisher nur von proteolytischen Enzymen bekannt war. Die drastische Beschleunigung bei geringer Kraft geht einer moderaten weiteren Beschleunigung bei Kräften im nN‐Bereich voraus. Quantenmechanochemische Ab‐initio‐Rechnungen erklären diese experimentellen Befunde sowohl mechanistisch als auch kinetisch. Unsere Ergebnisse zeigen, dass die Stabilität der Amidbindung entgegen bisherigen Annahmen stark kraftabhängig ist. Sie vermitteln ein grundlegendes Verständnis der Rolle mechanischer Aktivierung bei der Amidhydrolyse und weisen den Weg für mögliche Anwendungen, vom Recycling makromolekularer Reststoffe bis hin zum Design biotechnologisch hergestellter proteolytischer Enzyme.
α‐Arylierung von Carbonylverbindungen mittels oxidativer C‐C‐Bindungsaktivierung
Authors: Li Jing , Bauer Adriano , Di Mauro Giovanni , Maulide Nuno
Published: May 2019

Eine synthetisch nützliche Methode für die direkte α‐Arylierung von Carbonylverbindungen mittels einer neuartigen, oxidativen C‐C‐Bindungsaktivierung wird vorgestellt. Dieser mechanistisch unübliche Prozess baut auf einer 1,2‐Aryl‐Umlagerung auf, welche zur Bildung von quaternären, vollständig mit Kohlenstoff substituierten Zentren führt. Die Umsetzung weist eine breite Toleranz gegenüber funktionellen Gruppen auf und ist prinzipiell auch in einer asymmetrischen Variante möglich.
Efficient Separation of cis‐ and trans‐1,2‐Dichloroethene Isomers by Adaptive Biphen[3]arene Crystals
Authors: Wang Yiliang , Xu Kaidi , Li Bin , Cui Lei , Li Jian , Jia Xueshun , Zhao Hongbin , Fang Jianhui , Li Chunju
Published: May 2019

Reported here is the highly efficient separation of industrially important cis‐ and trans‐1,2‐dichloroethene (cis‐DCE and trans‐DCE) isomers by activated crystalline 2,2′,4,4′‐tetramethoxyl biphen[3]arene (MeBP3) materials, MeBP3α. MeBP3 can be synthesized in excellent yield (99 %), and a cyclic pentamer is also obtained when using 1,2‐dichloroethane as the solvent. The structure of MeBP3 in the CH3CN@MeBP3 crystal displays a triangle‐shape topology, forming 1D channels through window‐to‐window packing. Desolvated crystalline MeBP3 materials, MeBP3α, preferentially adsorb cis‐DCE vapors over its trans isomer. MeBP3α is able to separate cis‐DCE from a 50:50 (v/v) cis/trans‐isomer mixture, yielding cis‐DCE with a purity of 96.4 % in a single adsorption cycle. Single‐crystal structures and powder X‐ray diffraction patterns indicate that the uptake of cis‐DCE triggers a solid‐state structural transformation of MeBP3, suggesting the adaptivity of MeBP3α materials during the sorption process. Moreover, the separation can be performed over multiple cycles without loss of separation selectivity and capacity.
Mechanical Activation Drastically Accelerates Amide Bond Hydrolysis, Matching Enzyme Activity
Authors: Pill Michael F. , East Allan L. L. , Marx Dominik , Beyer Martin K. , Clausen‐Schaumann Hauke
Published: May 2019

Amide bonds, which include peptide bonds connecting amino acids in proteins and polypeptides, give proteins and synthetic polyamides their enormous strength. Although proteins and polyamides sustain mechanical force in nature and technology, how forces affect amide and peptide bond stability is still unknown. Using single‐molecule force spectroscopy, we discover that forces of only a few hundred pN accelerate amide hydrolysis 109‐fold, an acceleration hitherto only known from proteolytic enzymes. The drastic acceleration at low force precedes a moderate additional acceleration at nN forces. Quantum mechanochemical ab initio calculations explain these experimental results mechanistically and kinetically. Our findings reveal that, in contrast to previous belief, amide stability is strongly force dependent. These calculations provide a fundamental understanding of the role of mechanical activation in amide hydrolysis and point the way to potential applications from the recycling of macromolecular waste to the design of bioengineered proteolytic enzymes.
A Safe and Efficient Strategy for the Rapid Elimination of Blood Lead In Vivo Based on a Capture–Fix–Separate Mechanism
Authors: Wan Mi Mi , Xu Ting Ting , Chi Bo , Wang Meng , Huang Yangyang , Wang Qi , Li Ting , Yan Wen Qiang , Chen Huan , Xu Ping , Mao Chun , Zhao Bo , Shen Jian , Xu Hong , Shi Dong Quan
Published: May 2019

Lead poisoning is an important problem because of its serious effects on human health. Yet a solution is not available due to an incomplete understanding of the state of lead ions in blood. Since most blood lead binds to hemoglobin (Hb) in red blood cells, identifying and capturing lead‐contaminated Hb in RBCs is important. Herein, a magnetic blood lead remover with hyperbranched poly(amidoamine)s (HPAM) as template/co‐adsorbent and core–shell mesoporous structure was synthesized. Lead‐containing Hb was selectively captured and then fixed by mesoporous channels. The magnetic separation technology was used to separate the magnetic remover from blood. A related blood lead clean‐up apparatus was used to remove lead from the blood of a pig in vivo. Results of physical/chemical characterizations, biocompatibility experiments, animal tests, and theoretical simulation verify the safety and efficiency of this removal strategy and the high efficiency of the blood lead clean‐up apparatus.
Nanobody‐Conjugated Nanotubes for Targeted Near‐Infrared In Vivo Imaging and Sensing
Authors: Mann Florian A. , Lv Zhiyi , Großhans Jörg , Opazo Felipe , Kruss Sebastian
Published: May 2019

Fluorescent nanomaterials such as single‐walled carbon nanotubes (SWCNTs) have many advantages in terms of their photophysics, but it is difficult to target them to specific locations in living systems. In contrast, the green fluorescent protein (GFP) has been genetically fused to proteins in many cells and organisms. Therefore, GFP can be seen not only as a fluorophore but as a universal target/handle. Here, we report the conjugation of GFP‐binding nanobodies to DNA‐wrapped SWCNTs. This approach combines the targeting capabilities of GFP‐binding nanobodies and the nonbleaching near‐infrared fluorescence (850–1700 nm) of SWCNTs. These conjugates allow us to track single Kinesin‐5‐GFP motor proteins in developing embryos of Drosophila melanogaster. Additionally, they are sensitive to the neurotransmitter dopamine and can be used for targeted sensing of dopamine in the nm regime.
Basic properties of proton conductor BaZr0.1Ce0.7Y0.1Yb0.1O3‐δ (BZCYYb) material
Authors: Zhang Yifan , Xie Dong , Chi Bo , Pu Jian , Li Jian , Yan Dong
Published: May 2019

Proton conductor BaZr0.1Ce0.7Y0.1Yb0.1O3‐δ (BZCYYb) have a wide range of applications in solid oxide fuel cell due to its resistance to carbon deposition and good protonic conductivity. In this work, several basic properties of BZCYYb perovskite were studied: Structural phase transitions have been investigated with combination of differential scanning calorimeter, dilatometry, and high‐temperature X‐ray diffraction (XRD). Water absorption ability of BZCYYb in the temperature range of 600°C to 800°C was measured by thermogravimetry (TG) in a certain concentration of water vapor; the results showed the best absorption ability of 4.2% weight gain at 600°C, corresponding to a water adsorption of 0.63 mmol/m2. Oxygen stoichiometry of BZCYYb from room temperature to 800°C increased from 0.1296 to 0.386 in air. Besides, we compared the conductivity in different atmospheres (dry and humid N2–H2 [5%] and dry and humid air), which showed the highest total conductivity in humid air and a lower conductivity activation energy in a reducing atmosphere. Finally, CO2 poisoning process of BZCYYb was analyzed by XRD and TG. Compared with the case of pure CO2, lower critical CO2 poisoning temperature and more BaCO3 were found in CO2–H2O, indicating the addition of water could promote the reaction.
Multiple morphologies of a poly(methyl methacrylate)‐block‐poly(N,N‐dimethyl aminoethyl methacrylate) copolymer with pH‐responsiveness and thermoresponsiveness
Authors: Hu Lizhi , Wang Yihan , Yin Qiang , Du Kai , Yin Qinjian
Published: May 2019

We successfully prepared a series of pH‐responsive and thermoresponsive poly(methyl methacrylate) (PMMA)‐block‐poly(N,N‐dimethyl aminoethyl methacrylate (PDMAEMA) copolymers via reversible addition–fragmentation chain‐transfer polymerization with PMMA as a macro chain‐transfer agent. Control over the chain length of PDMAEMA allowed the morphological transformation of PMMA‐b‐PDMAEMA. The critical water content and critical micelle concentration also depended on the length of the PDMAEMA block. UV–visible and fluorescence spectrum analyses indicated that the PMMA‐b‐PDMAEMA copolymer exhibited a lower critical solution temperature type phase transition in water. The particle size of PMMA‐b‐PDMAEMA was dominated by the pH value, as evidenced by dynamic light scattering and transmission electron microscopy. In addition, the PMMA‐b‐PDMAEMA copolymers exhibited good reversible thermoresponsive behavior between 33 and 38°C. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 47972.
Simultaneous enhancement of electrical conductivity and interlaminar shear strength of CF/EP composites through MWCNTs doped thermoplastic polyurethane film interleaves
Authors: Li Wei , Li Yuntao , Xiang Dong , Zhao Chunxia , Wang Bin , Li Hui , Han Hongchang
Published: May 2019

Carbon fiber‐reinforced epoxy (CF/EP) composites have been widely used in aerospace industry, while poor electrical conductivity and interlaminar shear fracture toughness could reduce their safety as structural components in use. In this work, we achieved simultaneous improvement in electrical conductivity and interlaminar shear strength through interleaved multi‐walled carbon nanotubes (MWCNTs) doped thermoplastic polyurethane (TPU) conductive thin films (CTFs), which were prepared by a solution casting method. The experimental results showed that the electrical conductivity of the laminates increased by about 13 and 16 times in the transverse and thickness directions with only about 1 wt % MWCNTs content in the laminates. The end‐notch flexure (ENF) tests showed that the mode II interlaminar fracture toughness (GIIC) of composites with 10 wt % MWCNTs CTF interleaf shows a significant increase of about 106%. The enhancement mechanism was further explored through microscopic morphological observation. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 47988.
Sampled‐data output feedback stabilization for a class of p‐norm switched stochastic nonlinear systems
Authors: Jiang Yan , Zhai Junyong , Ye Hui
Published: May 2019

This paper addresses the sampled‐data output feedback stabilization problem for a class of p‐norm switched stochastic nonlinear systems with uncontrollable and unobservable linearizations around the origin. With sampled measurements, a reduced‐order observer is constructed to estimate the unmeasurable states. Based on adding a power integrator technique and the homogeneous domination approach, a sampled‐data output feedback controller is designed. Subsequently, by choosing an appropriate Lyapunov‐Krasoviskii functional combined with stochastic analysis techniques, it is shown that the closed‐loop system is globally asymptotically stable in probability under the proposed controller with a proper sampling period. Finally, two examples are presented to illustrate the effectiveness of the proposed scheme.
Exploring diagnostic validity of the autism diagnostic observation schedule‐2 in South Korean toddlers and preschoolers
Authors: Lee Kyung Sook , Chung Suk Jin , Thomas Hannah R. , Park Jinah , Kim So Hyun
Published: May 2019

This study aims to provide the initial validity of the Autism Diagnostic Observation Schedule‐2 (ADOS‐2) Toddler Module and Module 1‐2 for South Korean toddlers and preschoolers. Based on 143 children, the ASD group (n = 68) showed significantly higher ADOS‐2 item and algorithm total scores as well as social affect and repetitive and restricted behaviors domain scores compared with children with nonspectrum (NS; n = 42) disorders and typically developing (TD; n = 33) children. Using lower algorithm cutoffs, sensitivities were excellent for the ASD versus NS/TD comparisons, ranging from 94% to 100% across different Modules. Specificities varied more, ranging from 82% to 100%. Internal consistency was strong with high item‐total correlations (r of 0.6–0.9) and Cronbach's Alphas (all above 0.7). Results demonstrated promising, initial evidence for the validity of the ADOS‐2 for South Korean toddlers and preschoolers from 1 to 4 years of age. The ADOS‐2 could be implemented, with minimal adaptations, in research and clinical settings in South Korea. This study is one of the first steps toward validating the ADOS‐2 in other Eastern countries that are in great need for a valid instrument for the detection of ASD. Autism Res 2019, 12: 1356–1366. © 2019 International Society for Autism Research, Wiley Periodicals, Inc.

Lay Summary

Results of this study demonstrated promising, initial evidence for the validity of a gold standard measure for the diagnosis of autism, the Autism Diagnostic Observation Schedule‐2 (ADOS‐2), for South Korean toddlers and preschoolers. The ADOS‐2 could be implemented, with minimal adaptations, in research and clinical settings in South Korea. This study is one of the first steps toward validating the ADOS‐2 in other Eastern countries that are in great need of a valid instrument for the detection of ASD.
Proactive environmental strategy, innovation capability, and stakeholder integration capability: A mediation analysis
Authors: Yang Defeng , Jiang Wei , Zhao Weihong
Published: May 2019

This study investigates the underlying mechanisms through which proactive environmental strategy develops organizational capabilities. The results of a survey of publicly listed companies in China reveal that proactive environmental strategy has a more positive influence on stakeholder integration capability than on innovation capability. Moreover, organizational learning plays a greater role in mediating the effect of proactive environmental strategy on innovation capability than on stakeholder integration capability, whereas cross‐functional coordination plays a greater role in mediating its effect on stakeholder integration capability than on innovation capability. These findings provide important implications on organizational capability building via proactive environmental strategy.
Tissue biomechanics of the human head are altered by Thiel embalming, restricting its use for biomechanical validation
Authors: Zwirner Johann , Scholze Mario , Ondruschka Benjamin , Hammer Niels
Published: May 2019

Thiel embalming is a well‐known method of anatomical fixation giving lifelike optical and haptic tissue properties. Beyond these characteristics, Thiel embalming may also be a promising method to provide lifelike tissues for validation purposes of human head biomechanics. Recent investigations using Thiel‐embalmed human tissues of the upper and lower limb yielded contradicting biomechanical results on fixation‐induced changes in the tissues' load‐deformation behavior. It is to date unclear if Thiel embalming may have a softening or stiffening effect on human soft tissues or no global effect on biomechanics compared to the fresh state, with the latter being the most desirable outcome. The given study aimed at assessing the effects of Thiel embalming on the uniaxial tensile properties of human head soft tissues. Age‐matched fresh and Thiel‐embalmed dura mater, temporalis muscle, temporalis muscle fascia, and scalp samples were examined. Dura, fascia, and scalp samples showed significantly different elastic moduli compared to fresh tissues (all P < 0.01). The observed ultimate tensile strength supports the theory of an increased collagen crosslinking of the embalmed tissues when compared to the fresh state. Thiel‐embalmed muscles failed any tensile testing approach as a result of the muscles dissolving due to the embalming. Furthermore, collagen integrity seems altered in scanning electron microscopy by the Thiel embalming, limiting their use for ultrastructural failure analyses. Thiel‐embalmed soft tissues may consequently not serve to reflect the biomechanical properties of the human head. Consequently, the application of Thiel embalming should be limited to preliminary tests for biomechanical purposes. Clin. Anat. 32:903–913, 2019. © 2019 Wiley Periodicals, Inc.
Barriers to obtaining prostate multi‐parametric magnetic resonance imaging in African‐American men on active surveillance for prostate cancer
Authors: Walton Eric L. , Deebajah Mustafa , Keeley Jacob , Fakhouri Shadi , Yaguchi Grace , Pantelic Milan , Rogers Craig , Park Hakmin , Menon Mani , Peabody James O. , Dabaja Ali , Alanee Shaheen
Published: May 2019

Purpose

Magnetic resonance imaging is playing an ever‐bigger role in the management of prostate cancer. This study investigated barriers to obtaining multi‐parametric MRI (mpMRI) in African‐American men on active surveillance for prostate cancer in comparison to white men affected by the same type of cancer.

Materials and Methods

Retrospective review of prostate mpMRI orders from August 2015 to October 2017 at a single health organization treating a diverse population was performed. Data was extracted from the electronic medical records and cancellations were examined based on the documented reason for mpMRI cancellation, race, median zip code household income, and distance from healthcare facility.

Results

Out of 793 prostate mpMRI orders, 201 (25%) went unscanned. Access to care issues accounted for 46% of unscanned orders. Patient cancellations were the most common, followed by difficulty contacting patients, and insurance denials. African‐American patients disproportionately went unscanned because institution staff were unable to contact patients (29% vs 10% in white men, P = 0.0015). Median zip code household income was significantly different between racial groups but did not vary between indication for cancellation.

Conclusions

African‐American prostate cancer patients' access to mpMRI is hindered more by barriers to care than White patients. Urology providers must consider these issues before using prostate mpMRI within their active surveillance pathways.
Nomograms for predicting long‐term overall survival and cancer‐specific survival in lip squamous cell carcinoma: A population‐based study
Authors: Hu Chuan-Yu , Pan Zhen-Yu , Yang Jin , Chu Xiu-Hong , Zhang Jun , Tao Xue-Jin , Chen Wei-Min , Li Yuan-Jie , Lyu Jun
Published: May 2019

Background

The goal of this study was to establish and validate two nomograms for predicting the long‐term overall survival (OS) and cancer‐specific survival (CSS) in lip squamous cell carcinoma (LSCC).

Methods

This study selected 4175 patients who were diagnosed with LSCC between 2004 and 2015 in the SEER (Surveillance, Epidemiology, and End Results) database. The patients were allocated randomly to a training cohort and validation cohort. Variables were selected using a backward stepwise method in a Cox regression model. Based on the predictive model with the identified prognostic factors, nomograms were established to predict the 3‐, 5‐, and 8‐year survival OS and CSS rates of LSCC patients. The accuracy of the nomograms was evaluated based on the consistency index (C‐index), while their prediction accuracy was evaluated using calibration plots. Decision curve analyses (DCAs) were used to evaluate the performance of our survival model.

Results

The multivariate analyses demonstrated that age at diagnosis, marital status, sex, race, American Joint Committee on Cancer stage, surgery status, and radiotherapy status were risk factors for both OS and CSS. The C‐index, area under the time‐dependent receiver operating characteristic curve, and calibration plots demonstrated the good performance of the nomograms. DCAs of both nomograms further showed that they exhibited good 3‐, 5‐, and 8‐year net benefits.

Conclusions

We have developed and validated LSCC prognosis nomograms for OS and CSS for the first time. These nomograms can be valuable tools for clinical practice when clinicians are helping patients to understand their survival risk for the next 3, 5, and 8 years.