bluuebunny/crossref_metadata_2025 huggingface dataset:
Development and internal validation of a nine-lncRNA prognostic signature for prediction of overall survival in colorectal cancer patients
Authors: Zhang Zhiqiao , Liu Qingbo , Wang Peng , Li Jing , He Tingshan , Ouyang Yanling , Huang Yiyan , Wang Weidong
Published: December 2018

Background

Colorectal cancer remains a serious public health problem due to the poor prognosis. In the present study, we attempted to develop and validate a prognostic signature to predict the individual mortality risk in colorectal cancer patients.

Materials and Methods

The original study datasets were downloaded from The Cancer Genome Atlas database. The present study finally included 424 colorectal cancer patients with wholly gene expression information and overall survival information.

Results

A nine-lncRNA prognostic signature was built through univariate and multivariate Cox proportional regression model. Time-dependent receiver operating characteristic curves in model cohort demonstrated that the Harrell’s concordance indexes of nine-lncRNA prognostic signature were 0.768 (95% CI [0.717–0.819]), 0.778 (95% CI [0.727–0.829]) and 0.870 (95% CI [0.819–0.921]) for 1-year, 3-year and 5-year overall survival respectively. In validation cohort, the Harrell’s concordance indexes of nine-lncRNA prognostic signature were 0.761 (95% CI [0.710–0.812]), 0.801 (95% CI [0.750–0.852]) and 0.883 (95% CI [0.832–0.934]) for 1-year, 3-year and 5-year overall survival respectively. According to the median of nine-lncRNA prognostic signature score in model cohort, 424 CRC patients could be stratified into high risk group (n = 212) and low risk group (n = 212). Kaplan–Meier survival curves showed that the overall survival rate of high risk group was significantly lower than that of low risk group (P < 0.001).

Discussion

The present study developed and validated a nine-lncRNA prognostic signature for individual mortality risk assessment in colorectal cancer patients. This nine-lncRNA prognostic signature is helpful to evaluate the individual mortality risk and to improve the decision making of individualized treatments in colorectal cancer patients.
Association of urinary activity of MMP-9 with renal impairment in Mexican patients with type 2 diabetes mellitus
Authors: García-Tejeda Alan Uriel , Sampieri Clara Luz , Suárez-Torres Irene , Morales-Romero Jaime , Demeneghi-Marini Verónica Patricia , Hernández-Hernández Magda Elena , Rodríguez-Hernández Arturo
Published: December 2018

Background

Diabetic kidney disease is the most common cause of chronic kidney disease (CKD). An early event in diabetic kidney disease is alteration of the glomerular basement membrane and the mesangial expansion. Matrix metalloproteinases (MMP) are a family of endopeptidases responsible for controlling the pathophysiological remodeling of tissues, including renal tissues. MMP-9 in human urine has been proposed as a marker of diabetic nephropathy and urinary tract infections (UTI).

Methods

A cross-sectional study was conducted in type 2 diabetes mellitus (T2DM) patients who receive first level medical attention in Mexico. We used ELISA to measure MMP-9 levels in the urine of subjects with T2DM ≥ 18 years of age, who fulfilled the clinical requirements for calculation of glomerular filtration rate (GFR), according to the K/DOQI guide, in an attempt to identify whether MMP-9 levels in T2DM differ in patients with and without renal impairment. Univariate and multivariable analyses were performed in order to identify the association between MMP-9 and renal impairment.

Results

Included in the study were 34 (45%) subjects with renal impairment and 42 (55%) without. In the group with renal impairment, 10 subjects corresponded to stages 1–2 and 24 subjects corresponded to stage 3, according to their values of GFR and urinary albumin, following that proposed by the K/DOQI. No differences were found relating to sex, age, having or not having a partner, education, being able to read and write a message and duration of T2DM. Moreover, no differences were found between the groups in terms of weight, height, body mass index, waist size in general and frequency of UTI. In contrast, serum creatinine and urinary albumin were higher in the group with renal impairment, while GFR was greater in the group without renal impairment. Levels of MMP-9 were greater in women compared to men. Through univariate analysis in the general population, the presence of MMP-9 and that of its percentile 90 (P90) P90 were associated with the renal impairment group; however, in patients without UTI, only the presence of MMP-9 was associated with the renal impairment group, and no association was found with its P90. Multivariate analysis revealed an association between MMP-9 and its P90 with renal impairment.

Discussion

It is necessary to validate sensitive and non-invasive biological markers of CKD. We demonstrate that the presence and P90 of urinary MMP-9 are associated with renal impairment in Mexican patients with T2DM. While high levels of MMP-9 were associated to females and UTI, the presence of UTI was not associated with the incidence of renal impairment.
Conservation in Museums
Authors: Hatchfield Pamela
Published: December 2018

Conservation practice in museums interfaces with curators, scientists, researchers, educators, and the public. In addition to providing conditions appropriate to the long‐term preservation of the material in the collection, it includes examination, documentation, and analysis of cultural artifacts. It also focuses on object treatment, to stabilize physical and chemical structures, but also to aid in their interpretation and understanding, by clarifying and enhancing their appearance through actions such as cleaning or visual compensation. This work is done in accordance with codes of ethics and guidelines for practice of professional organizations such as the American Institute for Conservation of Historic and Artistic Works (AIC).
Conservation of Stone and Petroglyphs
Authors: Gittins Mark
Published: December 2018

This entry gives a brief overview of some of the principal aspects of stone conservation, including preliminary work on stone characterization, documentation, and treatment planning and the criteria to be considered. This is followed by a description of various possible phases of an intervention: cleaning, consolidation, fills, retouching/patination, and protection. A summary of the more common methods and materials employed, with criteria concerning their use and some possible limitations, is also included.
Conservation Science
Authors: Murray Alison , Anastassiades Amandina
Published: December 2018

Conservation science, also known as heritage science, is an interdisciplinary field that focuses on preserving artistic and cultural heritage objects and contributes to an understanding of their context. Characterizing individual materials and their deterioration yields knowledge of the structure and properties of a heritage object and, along with identifying degradation pathways, furthers development of conservation treatments. Research also determines the ideal environmental conditions for heritage objects, for example, appropriate relative humidity and temperature ranges and lighting conditions. Recommendations for appropriate materials for exhibiting, storing, and transporting objects as well as for use in conservation treatments are also based on conservation science research. Conservation scientists specialize in specific analytical techniques and apply expert knowledge of sampling, sample preparation, data interpretation, and the significance of the results for cultural heritage. These professionals work closely with others, for example conservators, archaeologists, art historians, and curators.
Cosmic‐Ray Muon Tomography
Authors: Schwitters Roy F.
Published: December 2018

The physical basis for muon tomography is described with reference to its invention and first use to image the interior of the Second Pyramid of Chephren. Muons are unstable, charged particles that make up most of the naturally occurring cosmic rays that can be detected at the Earth's surface. Cosmic‐ray muons penetrate tens of meters of dense matter, such as limestone, and are relatively easy to detect and track; their attenuation passing through matter is a measure of the total material along the muon's path. Computed tomography applied to detected muon tracks and attenuation creates 3D images of the structures through which they pass.
Cosmogenic Dating
Authors: Rixhon Gilles
Published: December 2018

Thanks to major theoretical and analytical progress, the use of terrestrial cosmogenic nuclides as geochronometers has considerably increased over the last three decades. These nuclides are the product of nuclear interactions between the secondary cosmic ray flux and the atomic nuclei of minerals constituting the uppermost part of the Earth's crust. Dating methods based on high‐precision concentration measurements of terrestrial cosmogenic nuclides yield numerical ages; they either assess the duration of exposure to cosmic rays (i.e. surface exposure dating), or the duration of shielding from these (i.e. burial dating). Both methods, which have provided decisive new insights into many fields of geosciences and archaeology, are presented in this entry.
Craniometry
Authors: von Cramon‐Taubadel Noreen
Published: December 2018

The study of human cranial form has a long history in anthropology. Cranial measurement schemes in common usage today trace their origins to the 18th and 19th century in response to the need for more rigorous and objective means of capturing the major dimensions of the cranium and mandible. Traditional craniometric methods center on the capture of linear dimensions between specific points on the skull (landmarks) taken with handheld calipers. In recent decades, geometric morphometric methods have become increasingly popular, whereby shape transformations in entire configurations of landmarks can be quantified and visualized simultaneously. Bioarchaeologists commonly employ craniometric data as a means of carrying out biodistance studies. These studies rely on the premise that human craniometric diversity patterns largely follow a neutral model of evolution, and therefore, craniometric data can be employed as a reliable proxy for neutral genetic data that are typically unavailable in many archaeological contexts.
Dental Development
Authors: Pilloud Marin A. , Heim Kelly
Published: December 2018

Dental development is a complex, yet genetically controlled process. As teeth develop during childhood, they serve as a means to study this period of development. Disruptions in the process of dental development can indicate episodes of childhood stress, and studies of the isotopic signatures of teeth can indicate childhood diet and mobility patterns. Dental development is also linked to life‐history events and can be used in studies of bioarchaeology and human evolution. Finally, an understanding of dental development is important in other research that relies on teeth as a source of data, including dental morphology and metrics.
Designing and Co‐Creating Heritage
Authors: Westin Jonathan
Published: December 2018

While often viewed as a tradition, a materiality, or a way of life, heritage is also a product of narration and communication where artifacts, places, and values are given context and meaning through various representations. These representations of heritage, which we meet not only in museums or scientific works but also in popular culture and as active identities, are the result of an ongoing negotiation with the past that includes a large number of co‐creators. The communicative conventions these representations make use of make up a large part of the public's apprehension of what cultural heritage is.
Organic Residue Analysis
Authors: Evershed Richard P. , Roffet‐Salque Mélanie
Published: December 2018

Organic residue analysis utilizes analytical organic chemical techniques to identify the nature and origins of organic remains that cannot be identified using traditional techniques of archaeological investigation because they are either amorphous, invisible, or present at trace concentrations. Investigations have confirmed the survival of a wide range of compounds at archaeological sites in association with various archaeological artifacts, ecofacts, and deposits. Compound classes identified include lipids, proteins, DNA, and pigments, but rarely carbohydrates. Chromatographic and mass spectrometric techniques are essential to separate and identify preserved biomolecular components termed “biomarkers,” which can be related databases of the components of modern animals and plants. The utility of biomarkers or their mixtures (termed “distributions,” “chemical fingerprints,” or “chemical signatures”) is enhanced by determination of their stable isotope compositions by gas chromatography combustion isotope ratio mass spectrometry (GC‐C‐IRMS). These approaches have been applied to a diverse range of artifacts, ecofacts and deposits to determine a wide range of activities relating to human activities in the past.
Osteology
Authors: Urista Cassady Yoder
Published: December 2018

Osteology is the scientific study of bone and is fundamental to a variety of disciplines including biological anthropology, zoology, paleontology, and anatomy. Human osteology is of particular interest to biological anthropologists and archaeologists, as the examination of the human skeleton can be very informative on topics of anthropological interest and the skeleton's durability means that it is often well preserved long after other biological tissues have decayed. The study of the skeleton can reveal basic information about the individual (sex, age‐at‐death, stature, etc.) but also, potentially, information about the health status and life history of the individual. This may be useful in archaeological, paleoanthropological, and forensic contexts.
Ostracods and Cladocerans
Authors: Palacios‐Fest Manuel R.
Published: December 2018

Ostracods and cladocerans are two important groups of crustaceans that play an important role in the environment, responding to climate change and human impact. This response is both somewhat different and complementary. Archaeologists and environmental scientists can use the remains of these animals to infer environmental change over time or the effects of anthropogenic activities. A summary of their taxonomic, biological, and ecological characteristics is provided in this entry.
Paleodemography and Hazards Analysis
Authors: De Witte Sharon N.
Published: December 2018

Paleodemography is the study of human population patterns in the past using skeletal samples excavated from archaeological sites. This entry summarizes the paleodemographic application of hazards analysis to derive demographic information from skeletal samples, highlighting commonly used hazard models (e.g., the Gompertz, Gompertz–Makeham, Siler, and Cox proportional hazards models) and the benefits they provide for those working with relatively small and incomplete skeletal samples.
Parasite Ova and Cysts
Authors: Morandi Lionello F.
Published: December 2018

The microscopic examination of archaeological samples containing parasite ova and cysts can provide a wealth of information. A range of animal and human intestinal parasites (e.g., tapeworms and roundworms) produce identifiable and resistant eggs, which are usually found in anthropogenic layers, fossil coprolites, and mummified bodies. The study of these remains can contribute to the knowledge of living conditions in ancient settlements, providing data on health, dietary habits, social status, and use of the space.
Pigment Alteration
Authors: Nevin Austin
Published: December 2018

Pigment alteration is often encountered in painted artifacts, wall paintings, and polychromy and it may cause a permanent change in appearance. Various factors contribute to pigment alteration and include the inherent instability of most pigments which may change color upon heating and exposure to light, or they may react with oxygen or other elements to form deterioration products. In this entry, selected cases of pigment alteration are presented together with methods used to study pigment deterioration mechanisms, which range from portable colorimetry to the use of synchrotron radiation.
Pigs
Authors: Albarella Umberto
Published: December 2018

The pig (Sus domesticus) was domesticated from the wild boar (Sus scrofa) more than 10,000 years ago in the Near East. It is likely that one or more domestication events occurred after this in other areas of the world. The pig rapidly became one of the most important domestic animals for human societies, a status that it has maintained to this day. Nevertheless, pork consumption is avoided in Muslim and Jewish cultures. Pigs do not provide secondary products and their rearing is almost exclusively geared towards food production. Pork consumption not only has a nutritional value, but also has played an important role in social (e.g., feasting) and religious contexts. Pigs could be managed in a variety of ways, ranging from free pasturing to sty enclosure. The different ways in which they were kept led to a diversity of pig morphological types. Free‐range pigs are typically slim and long‐snouted, while the enclosed pigs tend to be heavier and have a squashed skull profile.
Pollution and Heritage Conservation
Authors: Grzywacz Cecily M.
Published: December 2018

Pollution is a threat to heritage. There are local, regional, and continental sources of gases and particles that can cause harm to artifact and outdoor cultural property. Industries, vehicular traffic, agriculture, natural processes, atmospheric reactions, human activity, and materials generate pollutants. The concentration range that is a risk to heritage is in part per billions or micrograms per cubic meter. Conservators need to understand the material composition of heritage in order to manage the risks from pollution.
Positivism
Authors: Rodriguez Amparo Gómez
Published: December 2018

This entry examines the influence of positivism on archaeology, with particular emphasis on the impact of neopositivism during the twentieth century. It describes how this philosophy gave rise to “new archaeology,” also known as processual archaeology, which broke away from the traditional historicist approach and became a dominant field of research, particularly between 1960 and 1980, until the emergence of post‐processual archaeology. The basic tenet was that archaeology was a general science and was related to anthropology. As a science, archaeology adopted the requirements of neopositivism, using research into archaeological records to formulate hypotheses regarding the underlying processes of cultures of the past which, if confirmed, gave rise to laws which enabled scientific explanations of the nature of past organizations and how and why they changed.
Pottery Data Quantification
Authors: Kampel Martin , Sarkisjan Juraj
Published: December 2018

Pottery is the most frequent artifact studied by archaeologists. Given its high frequency, scholars have developed various methods for its quantification, including 3D scans and profile lines. Quantifying and documenting pottery benefits greatly from computerized assistance, as the human ability to distinguish and identify pottery sherds is limited. The application of computer vision methods provides a large number of data and new, challenging, and interesting conceptual problems. These new challenges are accentuated by describing and presenting pottery as a 3D surface in order to reconstruct a complete vessel from a single fragment.
Public Archaeology
Authors: Moshenska Gabriel , Zuanni Chiara
Published: December 2018

Public archaeology examines the points of contact between archaeologists and the wider world, and seeks to improve and promote these relationships. As a practice, it is as old as archaeology, but as a field of study it is relatively modern. It focuses on fields as diverse as education, nationalist politics, heritage in wartime, and the ethics of repatriating cultural property. The growth of digital media in public archaeology provides a range of opportunities, including new approaches to old problems, and the discipline continues to grow in scope and ambition.
PortableX‐Ray Fluorescence Spectrometry (pXRF)
Authors: Tykot Robert H.
Published: December 2018

Elemental analysis is a widely used method applied to archaeological materials to address their bulk composition, and/or identify the source of their geological components. The use of portable XRF instruments allows rapid, non‐destructive analyses to be conducted in museums and other facilities around the world and on virtually any size artifact, with trace element sensitivity and excellent precision. This instrument is now widely used on obsidian artifacts, ceramics, metals, paintings, and soils.
Reflectance Transformation Imaging (RTI) in Conservation
Authors: Reedy Chandra L.
Published: December 2018

Reflectance transformation imaging (RTI) requires first capturing a series of digital images of an object. A computer algorithm then extracts data from the series to construct a new image type, which reveals surface information not visible in any of the single images or in the original object. With inexpensive equipment, free software, and active research leading to continuing improvements, RTI has become part of the standard toolkit of conservators. The enhanced surface morphology details visible in qualitative RTI reveal information about craft techniques and help conservators to document condition, assess effects of treatments, and monitor change. Quantitative RTI more accurately measures change over time on object surfaces. It requires care in arranging a repeatable photographic setup and use of reproducible methods very sensitive to detecting surface changes. Quantitative RTI can measure damage or deterioration over time, or the visual effects caused by the application of conservation materials or by treatment techniques.
Rice
Authors: Wang Wei‐Ming
Published: December 2018

Cultivated rice includes
Oryza sativa
(Asian rice) and
Oryza glaberrima
(African rice). It is a staple food for over half the world's population. With the increasing accumulation of data on early rice farming in the middle and lower reaches of the Yangtze River, this region has become an important place for tracing the origin and development of rice agriculture. Genetic evidence shows that Asian rice, both indica and japonica groups, spring from a single domestication of the wild rice
Oryza rufipogon
that occurred 8,200–13,500 years ago in South China. African rice is believed to have been domesticated from its wild ancestor
Oryza barthii
in the inland delta of the Upper Niger River some 2,000–3,000 years ago. Nowadays, high‐yield crops, like hybrid rice, are one of the most important tools for combating world food crises, while the cultivation and use of genetically modified rice remains controversial.
Sampling in Marine Field
Authors: Sills E. Cory
Published: December 2018

The sampling of archaeological deposits in a marine field reveals advances in our understanding of human–environment interactions. The sampling of traditional archaeological materials as well as analytical techniques in a marine setting is discussed. Sampling methods for extracting sediment from a marine setting include cores, shovel testing, and dredging. Analytical techniques include particle size analysis, chemical analysis, magnetic susceptibility, loss‐on‐ignition, macroscopic analysis, pollen analysis, and sensitive environmental indicators such as ostracods and foraminifera. These techniques have been applied to a wide variety of marine settings, including near‐shore, offshore, and on continental shelves.
Starch Granule Analysis
Authors: Crowther Alison
Published: December 2018

Starch granule analysis is a paleoethnobotanical technique used to study past human–plant interactions. Starch forms as microscopic granules in a range of plants, particularly those used as foods such as cereals, legumes, and underground storage organs, and can be recovered archaeologically from food‐processing tools, sediments, dental calculus, and coprolites. Variations in the size and shape of starch grains permit their taxonomic identification. As in many starch‐producing plants, diagnostic remains, such as seeds, pollen, or phytoliths, either are not produced or do not preserve well, and starch granule analysis has become an important avenue for studying past human diet, food processing, and early agriculture around the world.
Statistics in Archaeology
Authors: Carlson David L.
Published: December 2018

Statistics are widely used in archaeological research to summarize objects and features in terms of quantity, composition, size, and shape. The use of statistics can be broadly grouped into: descriptive statistics; inferential statistics, including frequentist and Bayesian approaches and sampling statistics; and statistical learning and multivariate analysis, including related approaches such as exploratory data analysis, data mining, or machine learning. Statistical analysis of archaeological data generally falls into one of five broad domains: composition, chronology, classification, spatial distribution, and quanta.
Structure from Motion
Authors: Green Susie
Published: December 2018

Structure from motion is a computer vision technology based on photogrammetry. A series of digital photographs are processed to create a 3D point cloud. This can be georeferenced using control points and processed further to create a 3D surface model, orthographic images, or digital elevation maps, or brought into GIS software for analysis. The only tools required are a handheld, uncalibrated digital camera, which makes it suitable for archaeological fieldwork. Structure from motion is a relatively new technology and is likely to undergo further significant development.
Substances and Materials
Authors: Bauer Andrew M.
Published: December 2018

This entry discusses the conception of substances as different types of materials common in archaeological science within the context of different philosophical paradigms. Philosophical orientations that emphasize the ontological primacy of different substances generally stress the essence or intrinsic attributes, dispositions, or nature of particular entities that make up the world. In contrast, processual and relational frameworks privilege interactions or make shared relations among metaphysical components more foundational to the nature of being than essences or individualized particulars with inherent attributes; substances and the properties of materials are not innate, but context dependent. These distinctions hold a number of conceptual and practical implications for archaeological epistemology and historiography. Recent emphases on the dynamics of substances to crafting material worlds and shaping historical processes open new possibilities for the archaeological sciences to contribute to broader conversations in the humanities and social sciences.
Coercive control during the transition to parenthood: An overlooked factor in intimate partner violence and family wellbeing?
Authors: Gou Lisa H. , Duerksen Kari N. , Woodin Erica M.
Published: December 2018

A key criticism of research on intimate partner violence (IPV) is that a sole focus on physical or psychological acts of aggression fails to account for other forms of manipulative behavior that may have serious consequences for partner and family functioning. The current study examines coercive control, or behavior designed to constrain or compel an intimate partner in some way, in a longitudinal community sample of 98 heterosexual couples assessed in the third trimester of pregnancy as well as at 1 and 2 years postpartum. We found that the majority of couples reported at least some coercive controlling behavior during the transition to parenthood, that coercive control was highly bi‐directional between partners, and that women were more likely than men to engage in coercive control before parenthood. Using multilevel actor‐partner interdependence modeling, we found that women's coercive control predicted their own as well as men's perpetration of IPV across the transition to parenthood. Controlling for IPV perpetration by both partners, women's coercive control was longitudinally predictive of men's depression, harmful alcohol use, relationship dissatisfaction, poor co‐parenting, low perceived parenting competence, and perceptions of toddler problem behavior. Men's coercive control was longitudinally predictive of women's relationship dissatisfaction and parenting stress, as well as women's perceptions of infant problem behavior. Men's coercive control was associated with their own use of ineffective parenting behavior. These findings suggest that coercive control is common in community samples during the transition to parenthood and that coercive control predicts lower early family functioning.
Real‐time identification of nonlinear multiple‐input–multiple‐output systems with unknown input time delay using Wiener model with Neuro‐Laguerre structure
Authors: Sadeghi Mohsen , Farrokhi Mohammad
Published: December 2018

In this article, a real‐time block‐oriented identification method for nonlinear multiple‐input–multiple‐output systems with input time delay is proposed. The proposed method uses the Wiener structure, which consists of a linear dynamic block (LDB) followed by a nonlinear static block (NSB). The LDB is described by the Laguerre filter lattice, whereas the NSB is characterized using the neural networks. Due to the online adaptation of the parameters, the proposed method can cope with the changes in the system parameters. Moreover, the convergence and bounded modeling error are shown using the Lyapunov direct method. Four practical case studies show the effectiveness of the proposed algorithm in the open‐loop and closed‐loop identification scenarios. The proposed method is compared with the recently published methods in the literature in terms of the modeling accuracy, parameter initialization, and required information from the system.
Understanding the Role of Ferroelastic Domains on the Pyroelectric and Electrocaloric Effects in Ferroelectric Thin Films
Authors: Pandya Shishir , Velarde Gabriel A. , Gao Ran , Everhardt Arnoud S. , Wilbur Joshua D. , Xu Ruijuan , Maher Josh T. , Agar Joshua C. , Dames Chris , Martin Lane W.
Published: December 2018

Temperature‐ and electric‐field‐induced structural transitions in a polydomain ferroelectric can have profound effects on its electrothermal susceptibilities. Here, the role of such ferroelastic domains on the pyroelectric and electrocaloric response is experimentally investigated in thin films of the tetragonal ferroelectric PbZr0.2Ti0.8O3. By utilizing epitaxial strain, a rich set of ferroelastic polydomain states spanning a broad thermodynamic phase space are stabilized. Using temperature‐dependent scanning‐probe microscopy, X‐ray diffraction, and high‐frequency phase‐sensitive pyroelectric measurements, the propensity of domains to reconfigure under a temperature perturbation is quantitatively studied. In turn, the “extrinsic” contributions to pyroelectricity exclusively due to changes between the ferroelastic domain population is elucidated as a function of epitaxial strain. Further, using highly sensitive thin‐film resistive thermometry, direct electrocaloric temperature changes are measured on these polydomain thin films for the first time. The results demonstrate that temperature‐ and electric‐field‐driven domain interconversion under compressive strain diminish both the pyroelectric and the electrocaloric effects, while both these susceptibilities are enhanced due to the exact‐opposite effect from the extrinsic contributions under tensile strain.
Amorphous Quantum Nanomaterials
Authors: Kohle Ferdinand F. E. , Hinckley Joshua A. , Li Songying , Dhawan Nikhil , Katt William P. , Erstling Jacob A. , Werner‐Zwanziger Ulrike , Zwanziger Josef , Cerione Richard A. , Wiesner Ulrich B.
Published: December 2018

In quantum materials, macroscopic behavior is governed in nontrivial ways by quantum phenomena. This is usually achieved by exquisite control over atomic positions in crystalline solids. Here, it is demonstrated that the use of disordered glassy materials provides unique opportunities to tailor quantum material properties. By borrowing ideas from single‐molecule spectroscopy, single delocalized π‐electron dye systems are isolated in relatively rigid ultrasmall (<10 nm diameter) amorphous silica nanoparticles. It is demonstrated that chemically tuning the local amorphous silica environment around the dye over a range of compositions enables exquisite control over dye quantum behavior, leading to efficient probes for photodynamic therapy (PDT) and stochastic optical reconstruction microscopy (STORM). The results suggest that efficient fine‐tuning of light‐induced quantum behavior mediated via effects like spin‐orbit coupling can be effectively achieved by systematically varying averaged local environments in glassy amorphous materials as opposed to tailoring well‐defined neighboring atomic lattice positions in crystalline solids. The resulting nanoprobes exhibit features proven to enable clinical translation.
Enhancement of the Second Harmonic Generation from WS2 Monolayers by Cooperating with Dielectric Microspheres
Authors: Li Xiaohong , Liu Weiwei , Song Yiling , Zhang Cong , Long Hua , Wang Kai , Wang Bing , Lu Peixiang
Published: December 2018

Herein, a 20‐fold enhancement of the optical second harmonic generation (SHG) from WS2 monolayers by cooperating with SiO2 dielectric microspheres (MSs) is reported. Detailed experiment and simulation studies indicate that the SHG enhancement is dominantly originated by the enhanced excitation intensity and enlarged collection efficiency produced by the SiO2 MSs. The size effect of the SiO2 MS on the SHG enhancement is also systematically investigated. Moreover, the SHG enhancement is found to be very sensitive to the surrounding refractive index of the SiO2 MS, which advocates great promise for the photonic sensing applications. This work provides a low‐cost and efficient approach to enhancing the SHG emission, and demonstrates great potential for functional nanodevices based on hybrid dielectric structures.
Molecular Engineering of Copper Phthalocyanines: A Strategy in Developing Dopant‐Free Hole‐Transporting Materials for Efficient and Ambient‐Stable Perovskite Solar Cells
Authors: Jiang Xiaoqing , Wang Dongping , Yu Ze , Ma Wanying , Li Hai‐Bei , Yang Xichuan , Liu Feng , Hagfeldt Anders , Sun Licheng
Published: December 2018

Copper (II) phthalocyanines (CuPcs) have attracted growing interest as promising hole‐transporting materials (HTMs) in perovskite solar cells (PSCs) due to their low‐cost and excellent stability. However, the most efficient PSCs using CuPc‐based HTMs reported thus far still rely on hygroscopic p‐type dopants, which notoriously deteriorate device stability. Herein, two new CuPc derivatives are designed, namely CuPc‐Bu and CuPc‐OBu, by molecular engineering of the non‐peripheral substituents of the Pc rings, and applied as dopant‐free HTMs in PSCs. Remarkably, a small structural change from butyl groups to butoxy groups in the substituents of the Pc rings significantly influences the molecular ordering and effectively improves the hole mobility and solar cell performance. As a consequence, PSCs based on dopant‐free CuPc‐OBu as HTMs deliver an impressive power conversion efficiency (PCE) of up to 17.6% under one sun illumination, which is considerably higher than that of devices with CuPc‐Bu (14.3%). Moreover, PSCs containing dopant‐free CuPc‐OBu HTMs show a markedly improved ambient stability when stored without encapsulation under ambient conditions with a relative humidity of 85% compared to devices containing doped Spiro‐OMeTAD. This work thus provides a fundamental strategy for the future design of cost‐effective and stable HTMs for PSCs and other optoelectronic devices.
The germline JAK2 GGCC (46/1) haplotype and survival among 414 molecularly‐annotated patients with primary myelofibrosis
Authors: Tefferi Ayalew , Lasho Terra L. , Mudireddy Mythri , Finke Christy M. , Hanson Curtis A. , Ketterling Rhett P. , Gangat Naseema , Pardanani Animesh
Published: December 2018

JAK2 mutations in myeloproliferative neoplasms (MPNs) are associated with the germline GGCC (46/1) haplotype. In 2010, we reported an association between shortened survival in primary myelofibrosis (PMF) and nullizygosity for the JAK2 46/1 haplotype. In the current study, we have increased the number of informative cases from 130 to 414 (median age 63 years; 63% males), in order to revisit with the phenotypic and prognostic relevance of the JAK2 46/1 haplotype in PMF. JAK2 46/1 haplotype was documented in 69% of the study patients, including 25% in homozygous and 44% in heterozygous state. Driver mutation frequency in patients homozygous/heterozygous/nullizygous for the 46/1 haplotype was 78%/60%/56% JAK2, 10%/20%/18% type 1‐like CALR, 3%/2%/5% type 2‐like CALR, 4%/8%/7% MPL, and 6%/10%/14% triple‐negative (P = .02). In univariate analysis, nullizygosity for the JAK2 46/1 haplotype was associated with inferior overall survival (HR 1.5, 95% CI 1.1‐1.9), most pronounced in JAK2 (P <.001), as opposed to CALR/MPL mutated (P = .48) or triple‐negative cases (P = .27). Multivariable analysis that included karyotype, driver mutational status and high‐molecular risk mutations confirmed the independent prognostic contribution of nullizygosity for the 46/1 haplotype (P = .02; HR 1.4, 95% CI 1.1‐1.8). Nullizygosity for 46/1 also remained significant in the context of the genetically‐inspired GIPSS risk model (P = .04), but not in the context of the integrated genetics‐clinical MIPSS70+ version 2.0 model (P = .4). Leukemia‐free survival was not affected by the 46/1 haplotype (P = .6). The current study confirms the association of nullizygosity for the JAK2 GGCC (46/1) haplotype with inferior survival in JAK2‐mutated PMF.
One to One: Moving Forward While Facing Deep Differences
Authors: Schneider Andrea Kupfer , Honeyman Chris
Published: December 2018

Twelve years ago in these pages we wrote about our “Negotiator's Fieldbook “(ABA 2006). That book stood for more than a decade as the most comprehensive reference available on negotiation.
Poly(Alkyl Glycidate Carbonate)s as Degradable Pressure‐Sensitive Adhesives
Authors: Beharaj Anjeza , Ekladious Iriny , Grinstaff Mark W.
Published: December 2018

Insertion of CO2 into the polyacrylate backbone, forming poly(carbonate) analogues, provides an environmentally friendly and biocompatible alternative. The synthesis of five poly(carbonate) analogues of poly(methyl acrylate), poly(ethyl acrylate), and poly(butyl acrylate) is described. The polymers are prepared using the salen cobalt(III) complex catalyzed copolymerization of CO2 and a derivatized oxirane. All the carbonate analogues possess higher glass‐transition temperatures (Tg=32 to −5 °C) than alkyl acrylates (Tg=10 to −50 °C), however, the carbonate analogues (Td≈230 °C) undergo thermal decomposition at lower temperatures than their acrylate counterparts (Td≈380 °C). The poly(alkyl carbonates) exhibit compositional‐dependent adhesivity. The poly(carbonate) analogues degrade into glycerol, alcohol, and CO2 in a time‐ and pH‐dependent manner with the rate of degradation accelerated at higher pH conditions, in contrast to poly(acrylate)s.
A CO Adsorption Site Change Induced by Copper Substitution in a Ruthenium Catalyst for Enhanced CO Oxidation Activity
Authors: Huang Bo , Kobayashi Hirokazu , Yamamoto Tomokazu , Toriyama Takaaki , Matsumura Syo , Nishida Yoshihide , Sato Katsutoshi , Nagaoka Katsutoshi , Haneda Masaaki , Xie Wei , Nanba Yusuke , Koyama Michihisa , Wang Fenglong , Kawaguchi Shogo , Kubota Yoshiki , Kitagawa Hiroshi
Published: December 2018

Ru is an important catalyst in many types of reactions. Specifically, Ru is well known as the best monometallic catalyst for oxidation of carbon monoxide (CO) and has been practically used in residential fuel cell systems. However, Ru is a minor metal, and the supply risk often causes violent fluctuations in the price of Ru. Performance‐improved and cost‐reduced solid‐solution alloy nanoparticles of the Cu‐Ru system for CO oxidation are now presented. Over the whole composition range, all of the CuxRu1−x nanoparticles exhibit significantly enhanced CO oxidation activities, even at 70 at % of inexpensive Cu, compared to Ru nanoparticles. Only 5 at % replacement of Ru with Cu provided much better CO oxidation activity, and the maximum activity was achieved by 20 at % replacement of Ru by Cu. The origin of the high catalytic performance was found as CO site change by Cu substitution, which was investigated using in situ Fourier transform infrared spectra and theoretical calculations.
Tuning Thiol‐Based Self‐Assembled Monolayer Chemistry on a Gold Surface towards the Synthesis of Biochemical Fuel
Authors: Li Guangle , Fei Jinbo , Xu Youqian , Sun Bingbing , Li Junbai
Published: December 2018

A proton gradient across a lipid membrane is required for the production of biochemical fuel. Much effort has been devoted to reactions involving proton production in biomimetic assembled architectures under mild conditions. Herein, we explored thiol‐based self‐assembled monolayer chemistry on a naked gold surface for the production of biochemical fuel. Protons are generated when alkanethiols self‐assemble on a gold surface, and the proton yield can be tuned by the choice of thiol and by variation of the procedure used for the deposition of gold. Consequently, the proton gradient across a lipid membrane above the gold surface can be modulated to vary the production rate of biochemical fuel performed by lipid‐embedded motor proteins. Our work presents evidence that a simple and efficient abiotic chemical reaction in a well‐defined biohybrid system can convert unnatural chemicals, namely alkanethiols, into bioenergy molecules, a finding that has a great potential in biofuel‐driven catalysis and devices.
Enantioselective Aluminum‐Free Alkene Hydroarylations through C−H Activation by a Chiral Nickel/JoSPOphos Manifold
Authors: Loup Joachim , Müller Valentin , Ghorai Debasish , Ackermann Lutz
Published: December 2018

Highly enantioselective nickel‐catalyzed alkene endo‐hydroarylations were accomplished with full selectivity by organometallic C−H activation. The asymmetric assembly of chiral six‐membered scaffolds proved viable in the absence of pyrophoric organoaluminum reagents within an unprecedented nickel/JoSPOphos manifold.
Efficient Hyperpolarization of U‐13C‐Glucose Using Narrow‐Line UV‐Generated Labile Free Radicals
Authors: Capozzi Andrea , Patel Saket , Gunnarsson Christine Pepke , Marco‐Rius Irene , Comment Arnaud , Karlsson Magnus , Lerche Mathilde H. , Ouari Olivier , Ardenkjær‐Larsen Jan Henrik
Published: December 2018

Free radicals generated by UV‐light irradiation of a frozen solution containing a fraction of pyruvic acid (PA) have demonstrated their dissolution dynamic nuclear polarization (dDNP) potential, providing up to 30 % [1‐13C]PA liquid‐state polarization. Moreover, their labile nature has proven to pave a way to nuclear polarization storage and transport. Herein, differently from the case of PA, the issue of providing dDNP UV‐radical precursors (trimethylpyruvic acid and its methyl‐deuterated form) not involved in any metabolic pathway was investigated. The 13C dDNP performance was evaluated for hyperpolarization of [U‐13C6,1,2,3,4,5,6,6‐d7]‐d‐glucose. The generated UV‐radicals proved to be versatile and highly efficient polarizing agents, providing, after dissolution and transfer (10 s), a 13C liquid‐state polarization of up to 32 %.
Reductive Nitric Oxide Coupling at a Dinickel Core: Isolation of a Key cis‐Hyponitrite Intermediate en route to N2O Formation
Authors: Ferretti Eleonora , Dechert Sebastian , Demeshko Serhiy , Holthausen Max C. , Meyer Franc
Published: December 2018

Reductive coupling of nitric oxide (NO) to give N2O is an important reaction in the global nitrogen cycle. Here, a dinickel(II) dihydride complex 1 that releases H2 upon substrate binding and serves as a masked dinickel(I) scaffold is shown to reductively couple two molecules of NO within the bimetallic cleft. The resulting hyponitrite complex 2 features an unprecedented cis‐[N2O2]2− binding mode that has been computationally proposed as a key intermediate in flavodiiron nitric oxide reductases (FNORs). NMR and DFT evidence indicate facile rotational fluxionality of the [N2O2]2− unit, which allows to access an isomer that is prone to N2O release. Protonation of 2 is now found to trigger rapid N2O evolution and formation of a hydroxido bridged complex, reminiscent of FNOR reactivity. This work provides fundamental insight into the biologically relevant reductive coupling of two NO molecules and the subsequent trajectory towards N2O formation at bimetallic sites.
Rapid Assembly of Saturated Nitrogen Heterocycles in One‐Pot: Diazo‐Heterocycle “Stitching” by N–H Insertion and Cyclization
Authors: Boddy Alexander J. , Affron Dominic P. , Cordier Christopher J. , Rivers Emma L. , Spivey Alan C. , Bull James A.
Published: December 2018

Methods that provide rapid access to new heterocyclic structures in biologically relevant chemical space provide important opportunities in drug discovery. Here, a strategy is described for the preparation of 2,2‐disubstituted azetidines, pyrrolidines, piperidines, and azepanes bearing ester and diverse aryl substituents. A one‐pot rhodium catalyzed N–H insertion and cyclization sequence uses diazo compounds to stitch together linear 1,m‐haloamines (m=2–5) to rapidly assemble 4 ‐, 5 ‐, 6 ‐, and 7 ‐membered saturated nitrogen heterocycles in excellent yields. Over fifty examples are demonstrated, including examples with diazo compounds derived from biologically active compounds. The products can be functionalized to afford α,α‐disubstituted amino acids and applied to fragment synthesis.
Access to N‐Substituted 2‐Pyridones by Catalytic Intermolecular Dearomatization and 1,4‐Acyl Transfer
Authors: Xu Guangyang , Chen Ping , Liu Pei , Tang Shengbiao , Zhang Xinhao , Sun Jiangtao
Published: December 2018

A novel rhodium‐catalyzed dearomatization of O‐substituted pyridines to access N‐substituted 2‐pyridones has been developed. A computational study suggests a mechanism involving the formation of a pyridinium ylide followed by an unprecedented 1,4‐acyl migratory rearrangement from O to C. Furthermore, the chiral dirhodium complexes serve as the catalyst for the asymmetric transformation with excellent enantioselective control. DFT calculations indicate the chirality is transferred from axial chirality to the central stereogenic centre. The stronger π–π interaction and CH–π interaction account for the high enantioselectivity.
Divergent Synthesis of 3‐Deoxy‐d‐manno‐oct‐2‐ulosonic Acid (Kdo) Glycosides Containing α‐(2→4)‐Linked Kdo‐Kdo Unit
Authors: Zhou Xian‐Yang , Yang Pan , Luo Sheng , Yang Jin‐Song
Published: December 2018

A convenient and divergent approach was developed to prepare diverse bacterial 3‐deoxy‐d‐manno‐oct‐2‐ulosonic acid (Kdo) oligosaccharides containing a Kdo‐α‐(2→4)‐Kdo fragment. The orthogonal protected α‐(2→4) linked Kdo‐Kdo disaccharide 3, serving as a common precursor, was divergently transformed into the corresponding 8‐, 8′‐, and 4′‐hydroxy disaccharides 5, 7, and 14, respectively. Then, these alcohols were glycosylated, respectively, with the 5,7‐O‐di‐tert‐butylsilylene (DTBS) protected Kdo thioglycoside donors 1 or 2 in an α‐stereoselective and high‐yielding manner to afford a range of Kdo oligosaccharides. Finally, removal of all protecting groups of the newly formed glycosides resulted in the desired free Kdo oligomer.