bluuebunny/crossref_metadata_2025 huggingface dataset:
The CRH‐ACTH‐biogenic amine axis in invertebrate immunocytes activated by PDGF and TGF‐β
Authors: Ottaviani Enzo , Caselgrandi Eva , Kletsas Dimitris
Published: July 2002

In immunocytes from the mollusc Mytilus galloprovincialis, the major pathway followed by platelet‐derived growth factor (PDGF)‐AB and transforming growth factor (TGF)‐β1 in provoking the release of norepinephrine, epinephrine and dopamine into cell‐free hemolymph (serum) is mediated by a corticotropin‐releasing hormone‐adrenocorticotropin hormone (CRH‐ACTH) biogenic amine axis. This axis not only annulled the inhibiting properties of PDGF‐AB, it even reversed the latter's effect, while the inducing effect of TGF‐β1 was amplified. These findings show that non‐classical immune‐neuroendocrine molecules, such as PDGF‐AB and TGF‐β1, are involved in building stress response, using the same conserved mechanisms present from invertebrates to vertebrates.
Fate of unstable Bacillus subtilis subgenome: re‐integration and amplification in the main genome
Authors: Itaya Mitsuhiro , Tanaka Teruo
Published: July 2002

The plastic Bacillus subtilis genome was dissected into two physically separate genomes, the 3.9 Mb main genome and the 0.3 Mb subgenome. DNA replication of the main genome was initiated from the normal replication origin (oriC) and that of the subgenome was from a 7.2 kb oriN‐containing fragment artificially inserted. When the 7.2 kb fragment was shortened to a 1.5 kb fragment that contains oriN but lacks the segregational function, the subgenome became unstable and was rapidly lost from the cell, producing inviable cells due to the loss of essential genes carried by the subgenome. Stable survivors were isolated in which the subgenome had re‐integrated and multiplied in the main genome. These results suggest that a reduced genetic stability of the subgenome induces size variation of the B. subtilis genome.
Sensitized photomodification of mammalian DNA polymerase β. A new approach for highly selective affinity labeling of polymerases
Authors: Kolpashchikov D.M. , Rechkunova N.I. , Dobrikov M.I. , Khodyreva S.N. , Lebedeva N.A. , Lavrik O.I.
Published: July 2002

To enhance the specificity of polymerase photoaffinity labeling, a novel approach based on sensitized photomodification has been developed. A base‐substituted analog of TTP containing a pyrene group (PyrdUTP) was synthesized and used as an active site‐bound photosensitizer for photoaffinity modification of DNA polymerase β (pol β). 5′‐[32P]‐labeled primer was elongated in situ by pol β with a photoreactive analog of TTP (FAB‐4‐dUTP). The pyrene sensitizer (PyrdUTP), excited by light (365–450 nm), can activate the photoreagent, crosslinking it to pol β as a result of fluorescence resonance energy transfer. The initial rate of pol β photomodification was shown to increase by a factor of ten. The selectivity of pol β photosensitized modification was proved by adding human replication protein A.
Synaptic development in semi‐dissociated cultures of rat retina
Authors: Dhingra Narender K. , Reddy Rajini , Govindaiah  , Hemavathy U. , Raju Trichur R. , Ramamohan Y.
Published: July 2002

Cultured neurons provide a simpler and more accessible environment to study the synaptic physiology. However, it is not clear if development of synapses in culture is similar to that in the in vivo condition. We studied the developmental sequence and morphological differentiation of chemical synapses in semi‐dissociated rat retinal cultures that consisted of dissociated neurons as well as undissociated retinal aggregates. Synapses were quantified by synaptophysin immunoreactive puncta. During second week of in vitro development the average number of chemical synapses on the cell body decreased while that on the neurites increased significantly. Conventional synapses appeared both in aggregate and in dissociated neurons, with the developmental profile similar to that reported for in vivo retina. In contrast, the development of ribbon synapses was adversely affected by the in vitro microenvironment as suggested by following observations. The ribbon synapses were more frequently found in aggregate than in dissociated neurons, and were not associated with dyadic or triadic synaptic arrangement. The photoreceptor ribbons did not contact a postsynaptic process while bipolar ribbons made single (monadic) synapses. Further, photoreceptor ribbons in dissociated neurons were late to form and took more time to mature as compared to those in the aggregate cultures. Most of the rod bipolar cells, identified by their immunoreactivity to protein kinase C (PKC), had three or more neurites. Unlike in the in vivo retina, the dissociated rod bipolar cells did not show any PKC immunoreactive varicosities, suggesting that they failed to develop a well‐differentiated synaptic terminal. Interestingly, we did not find any parvalbumin positive AII amacrine cells that are normally postsynaptic to rod bipolar cells. These results show that the conventional synapses of retina, which are similar to chemical synapses in other parts of the brain, develop normally both in aggregate and dissociated neurons. However, the highly specialized ribbon synapses have more stringent developmental requirements, and their normal development may require the presence of postsynaptic neurons in their close vicinity.
Generic quality of life assessment in psychiatry. Potentials and limitations
Authors: Bullinger M
Published: July 2002

The term ‘quality of life’ has only recently been introduced to psychiatric outcome assessment. Current approaches to such assessment include the development of disease-specific quality of life instruments for psychiatric patient populations as well as the examination of generic quality of life instruments for use in psychiatric outcome studies. The current paper describes the psychiatric work with one example for a generic instrument: the short-form health survey questionnaire (SF-36). The 36 item patient-based questionnaire was developed within the Medical Outcome Study in the United States, was translated, validated and standardized in several countries and has been used in psychiatric settings. Results of epidemiological studies suggest that the SF-36 is applicable to psychiatric patients, is a psychometrically sound instrument also in this indication and yields relevant information in showing the degree of impairment in quality of life domains as experienced by psychiatric patients. The use of generic instruments in psychiatric population, such as the SF-36, might contribute to a better understanding of patients' quality of life as assessed in epidemiological studies, clinical trials and quality of care evaluations.
Readmitted nonpsychotic patients and their eventual diagnoses. A retrospective study on 64 first-timers of inpatient care in the Psychiatric Clinic of Turku, Finland
Authors: Korkeila JA , Karlsson H , Kujari H
Published: July 2002

This longitudinal study was performed to characterise frequently readmitted patients in a sample of 64 first-timers of inpatient care. Half of the 12 revolving door patients were psychotic at last discharge. The relative risk for diagnostic change in the Axis I group was nine times higher than in the personality disorder group.
Abivertinib synergistically strengthens the anti‐leukemia activity of venetoclax in acute myeloid leukemia in a BTK‐dependent manner
Authors: Huang Shujuan , Li Chenying , Zhang Xiang , Pan Jiajia , Li Fenglin , Lv Yunfei , Huang Jingwen , Ling Qing , Ye Wenle , Mao Shihui , Huang Xin , Jin Jie
Published: June 2020

B‐cell lymphoma 2 (BCL‐2), a crucial member of the anti‐apoptotic BCL‐2 family, is frequently dysregulated in cancer and plays an important role in acute myeloid leukemia (AML). Venetoclax is a highly selective BCL‐2 inhibitor that has been approved by the FDA for treating elderly AML patients. However, the emergence of resistance after long‐term treatment emphasizes the need for a deeper understanding of the potential mechanisms of resistance and effective rescue methods. By using RNA‐seq analysis in two human AML cohorts made up of three patients with complete remission and three patients without remission after venetoclax treatment, we identified that upregulation of BTK enabled AML blast resistance to venetoclax. Interestingly, we found that abivertinib, an oral BTK inhibitor, could synergize with venetoclax to inhibit the proliferation of primary AML cells and cell lines. It is worth noting that the combination of the two effectively enhanced the sensitivity of two AML patients (AML#3 and AML#12) to venetoclax. In this study, we demonstrated that combined use of the two drugs can synergistically inhibit the colony‐forming capacity of AML cells, arrest the AML cell cycle in the G0/G1 phase, and inhibit the BCL‐2 anti‐apoptotic family protein, activating the caspase family to induce apoptosis. Mechanistically, knockdown of BTK in AML cell lines impaired the synergistic effect of the two drugs. In vivo study showed similar results as those seen in vitro. Abivertinib in combination with venetoclax could significantly prolong the survival time and reduce the tumor burden of MV4‐11‐NSG mice compared with those of control and single‐agent groups. Our in vitro and in vivo studies have shown that the combination of abivertinib and venetoclax may benefit AML patients, especially in patients resistant to venetoclax or those that relapse. New clinical trials will be planned.
A review of patient questions from physicist—patient consults
Authors: Atwood Todd F. , Brown Derek W. , Juang Titania , Moore Kevin L. , McConnell Kristen A. , Steers Jennifer M. , Murphy James D. , Mundt Arno J. , Pawlicki Todd
Published: June 2020

Purpose

To provide insight into the types of questions asked to medical physicists by patients during one‐on‐one physicist–patient consults at one institution.

Materials and Methods

Medical physicists trained in patient communication techniques met with patients to provide an overview of the treatment planning and delivery processes, discuss the patient's treatment plan, and answer any technical questions. From August 2016 to December 2019, 152 physicist–patient consults were conducted. In the initial months of the study (August 2016—December 2017), following each physicist–patient consult, all patient questions were documented by the physicists. For the remaining time period (January 2018—December 2019), any newly encountered questions were periodically added to the list. The questions were compiled into a comprehensive list and organized into categories.

Results

There were a total of 88 unique patient questions. These questions fit into four topical categories. Fifty‐four questions (61.4%) were in the “Treatment Planning and Delivery Questions” category, 15 questions (17.1%) were in the “General Radiation Questions or Concerns” category, 13 questions (14.8%) were in the “Safety and Quality Assurance Questions” category, and 6 questions (6.8%) were in the “Medical Questions” category. Overall, patients were primarily concerned about how radiation works, the treatment planning and delivery processes, and what is being done to keep them safe throughout their treatment.

Conclusion

Physicist–patient consults provided an opportunity to address the technical aspects of radiation therapy with patients in greater detail. The fact that patient questions could be conveniently grouped into only four topical categories indicates that it may be straightforward for other medical physicists to prepare for effectively addressing technical questions during physicist–patient consults.
Impaired cognition is related to microstructural integrity in relapsing remitting multiple sclerosis
Authors: Zhao Lin , Ng Angel , Chen Qianyun , Lam Bonnie , Abrigo Jill , Au Cheryl , Mok Vincent C. T. , Wong Adrian , Lau Alexander Y.
Published: June 2020

Background

Cognitive impairment is common in multiple sclerosis (MS). However, the relationship between cognitive deficits and microstructural abnormalities in Chinese MS patients remains unclear. We aimed to investigate the importance of microstructural abnormalities and the associations with cognitive impairment in Chinese MS patients.

Methods

Three‐dimensional T1‐weighted magnetic resonance imaging (MRI) scans were obtained from 36 relapsing remitting MS patients. Diffusion tensor imaging (DTI) scans were acquired for 29 (81%) patients. Cognitive impairment was assessed using a comprehensive neuropsychological battery. Patients were classified into cognitively impaired (CI) group and cognitively preserved (CP) group. Using volBrain and FSL software, we assessed white matter lesion burden, white matter (WM) and gray matter (GM) volumetric as well as microstructural diffusivity. MRI variables explaining cognitive impairment were analyzed.

Results

Fifteen (42%) patients were classified as CI. Verbal learning and memory was the most commonly impaired domain (n = 16, 44%). CI patients had lower mean skeleton fractional anisotropy (FA) value than CP patients (275.45 vs. 283.61 × 10−3, P = 0.023). The final predicting model including demographic variables and global skeleton mean diffusivity (MD) explained 43.6% of variance of the presence of cognitive impairment (β = 0.131, P = 0.041). CI patients showed a widespread change of microstructural integrity comparing to CP patients, which was rarely overlapping with lesion probability map. Microstructural abnormalities in corpus callosum were associated with performance in verbal learning and memory, processing speed and selective attention (P < 0.05).

Conclusion

Loss of microstructural integrity demonstrated by DTI helps explain cognitive dysfunction in Chinese MS patients.
Enhanced Sensitivity of Capacitive Pressure and Strain Sensor Based on CaCu3Ti4O12 Wrapped Hybrid Sponge for Wearable Applications
Authors: Chhetry Ashok , Sharma Sudeep , Yoon Hyosang , Ko Seokgyu , Park Jae Yeong
Published: June 2020

Pressure sensors with highly sensitive and flexible characteristics have extensive applications in wearable electronics, soft robotics, human–machine interface, and more. Herein, an effective strategy is explored to enhance the sensitivity of the capacitive pressure sensor by fabricating a dielectric hybrid sponge consisting of calcium copper titanate (CaCu3Ti4O12, CCTO), a giant dielectric permittivity material, in polyurethane (PU). An ultrasoft CCTO@PU hybrid sponge is fabricated via dip‐coating the PU sponge into surface‐modified CCTO nanoparticles using 3‐aminopropyl triethoxysilane. The overall results show that the –NH2 functionalized CCTO attributes proper adhesion of CCTO with the –OCN group of the PU to enhance interfacial polarization leading to a high dielectric permittivity (167.05) and low loss tangent (0.71) beneficial for flexible pressure sensing applications. Moreover, the as‐prepared CCTO@PU hybrid sponge at 30 wt% CCTO concentration exhibits excellent electromechanical properties with an ultralow compression modulus of 27.83 kPa and a high sensitivity of 0.73 kPa−1 in a low‐pressure regime (<1.6 kPa). Finally, pressure and strain sensing performance is demonstrated for the detection of human activities by mounting the sensor on various parts of the human body. The work reveals a new opportunity for the facile fabrication of high performance CCTO‐based capacitive sensors with multifunctional properties.
Endothelial Regulation of Drug Transport in a 3D Vascularized Tumor Model
Authors: Haase Kristina , Offeddu Giovanni S. , Gillrie Mark R. , Kamm Roger D.
Published: June 2020

Drug discovery and efficacy in cancer treatments are limited by the inability of pre‐clinical models to predict successful outcomes in humans. Limitations remain partly due to their lack of a physiologic tumor microenvironment (TME), which plays a considerable role in drug delivery and tumor response to therapy. Chemotherapeutics and immunotherapies rely on transport through the vasculature, via the smallest capillaries and stroma to the tumor, where passive and active transport processes are at play. Here, a 3D vascularized tumor on‐chip is used to examine drug delivery in a relevant TME within a large bed of perfusable vasculature. This system demonstrates highly localized pathophysiological effects of two tumor spheroids (Skov3 and A549), which cause significant changes in vessel density and barrier function. Paclitaxel (Taxol) uptake is examined through diffusivity measurements, functional efflux assays, and accumulation of the fluorescent‐conjugated drug within the TME. Due to vascular and stromal contributions, differences in the response of vascularized tumors to Taxol (shrinkage and CD44 expression) are apparent compared with simpler models. This model specifically allows for examination of spatially resolved tumor‐associated endothelial dysfunction, likely improving the representation of in vivo drug distribution, and has potential for development into a more predictable model of drug delivery.
Temperature‐Mediated Engineering of Graphdiyne Framework Enabling High‐Performance Potassium Storage
Authors: Yi Yuyang , Li Jiaqiang , Zhao Wen , Zeng Zhihan , Lu Chen , Ren Hao , Sun Jingyu , Zhang Jin , Liu Zhongfan
Published: June 2020

Graphdiyne (GDY), an emerging type of carbon allotropes, possesses fascinating electrical, chemical, and mechanical properties to readily spark energy applications in the realm of Li‐ion and Na‐ion batteries. Nevertheless, rational design of GDY architectures targeting advanced K‐ion storage has rarely been reported to date. Herein, the first example of synthesizing GDY frameworks in a scalable fashion to realize superb potassium storage for high‐performance K‐ion battery (KIB) anodes is showcased. To begin with, first principles calculations provide theoretical guidances for analyzing the intrinsic potassium storage capability of GDY. Meanwhile, the specific capacity is predicted to be as high as 620 mAh g−1, which is considerably augmented as compared with graphite (278 mAh g−1). Experimental tests then reveal that prepared GDY framework indeed harvests excellent electrochemical performance as a KIB anode, achieving high specific capacity (≈505 mAh g−1 at 50 mA g−1), outstanding rate performance (150 mAh g−1 at 5000 mA g−1) and favorable cycling stability (a high capacity retention of over 90% after 2000 cycles at 1000 mA g−1). Furthermore, kinetic analysis reveals that capacitive effect mainly accounts for the K‐ion storage, with operando Raman spectroscopy/ex situ X‐ray photoelectron spectroscopy identifying good electrochemical reversibility of GDY.
Flat Lenses Based on 2D Perovskite Nanosheets
Authors: Wang Ziyu , Yang Tieshan , Zhang Yupeng , Ou Qingdong , Lin Han , Zhang Qianhui , Chen Huanyang , Hoh Hui Ying , Jia Baohua , Bao Qiaoliang
Published: June 2020

Ultrathin flat lenses based on metasurfaces or metamaterials have shown great promise in recent years as essential components in nano‐optical system, with capability of abrupt changes of light wavefronts. However, such structural designs require complex nanopatterns and a time‐consuming nanofabrication process. In this regard, flat lenses are developed based on 2D perovskite nanosheets, using a cost‐effective mask‐free femtosecond direct laser writing system. The optical properties of the 2D perovskite are rationally adjusted through facile composition engineering as well as thickness‐dependent quantum‐size confinement. A diffraction theory model is derived to understand the focusing mechanism of the 2D perovskite nanosheets flat lenses. The as‐fabricated lenses exploit the tunable material property variations to effectively manipulate not only the amplitude but also the phase of the incident light to focus into a 3D focal spot with a sub‐wavelength resolution in the range of 0.5–0.9λ. The results pave the way toward low‐cost and large‐scale high‐resolution imaging applications in the future.
High‐Performance All‐Polymer Solar Cells Enabled by n‐Type Polymers with an Ultranarrow Bandgap Down to 1.28 eV
Authors: Feng Kui , Huang Jiachen , Zhang Xianhe , Wu Ziang , Shi Shengbin , Thomsen Lars , Tian Yanqing , Woo Han Young , McNeill Christopher R. , Guo Xugang
Published: June 2020

Compared to organic solar cells based on narrow‐bandgap nonfullerene small‐molecule acceptors, the performance of all‐polymer solar cells (all‐PSCs) lags much behind due to the lack of high‐performance n‐type polymers, which should have low‐aligned frontier molecular orbital levels and narrow bandgap with broad and intense absorption extended to the near‐infrared region. Herein, two novel polymer acceptors, DCNBT‐TPC and DCNBT‐TPIC, are synthesized with ultranarrow bandgaps (ultra‐NBG) of 1.38 and 1.28 eV, respectively. When applied in transistors, both polymers show efficient charge transport with a highest electron mobility of 1.72 cm2 V−1 s−1 obtained for DCNBT‐TPC. Blended with a polymer donor, PBDTTT‐E‐T, the resultant all‐PSCs based on DCNBT‐TPC and DCNBT‐TPIC achieve remarkable power conversion efficiencies (PCEs) of 9.26% and 10.22% with short‐circuit currents up to 19.44 and 22.52 mA cm−2, respectively. This is the first example that a PCE of over 10% can be achieved using ultra‐NBG polymer acceptors with a photoresponse reaching 950 nm in all‐PSCs. These results demonstrate that ultra‐NBG polymer acceptors, in line with nonfullerene small‐molecule acceptors, are also available as a highly promising class of electron acceptors for maximizing device performance in all‐PSCs.
Photonic Multishells Composed of Cholesteric Liquid Crystals Designed by Controlled Phase Separation in Emulsion Drops
Authors: Park Sihun , Lee Sang Seok , Kim Shin‐Hyun
Published: June 2020

Cholesteric liquid crystals (CLCs), also known as chiral nematic LCs, show a photonic stopband, which is promising for various optical applications. In particular, CLCs confined in microcompartments are useful for sensing, lasing, and optical barcoding at the microscale. The integration of distinct CLCs into single microstructures can provide advanced functionality. In this work, CLC multishells with multiple stopbands are created by liquid–liquid phase separation (LLPS) in a simple yet highly controlled manner. A homogeneous ternary mixture of LC, hydrophilic liquid, and co‐solvent is microfluidically emulsified to form uniform oil‐in‐water drops, which undergo LLPS to form onion‐like drops composed of alternating CLC‐rich and CLC‐depleted layers. The multiplicity is controlled from one to five by adjusting the initial composition of the ternary mixture, which dictates the number of consecutive steps of LLPS. Interestingly, the concentration of the chiral dopant becomes reduced from the outermost to the innermost CLC drop due to uneven partitioning during LLPS, which results in multiple stopbands. Therefore, the photonic multishells show multiple structural colors. In addition, dye‐doped multishells provide band‐edge lasing at two different wavelengths. This new class of photonic multishells will provide new opportunities for advanced optical applications.
Toward Commercial Carbon Dioxide Electrolysis
Authors: Ganji Parameswaram , Borse Rahul Anil , Xie Jiafang , Mohamed Aya Gomaa Abdelkader , Wang Yaobing
Published: June 2020

The electrochemical carbon dioxide reduction reaction (ECDRR) driven by clean energy resources (such as wind, solar, etc.) to chemical feedstock and fuels is an attractive route to balance the carbon‐neutral cycle and for regenerating fuels. To date, the ECDRR has been the most promising technology for the conversion of carbon dioxide (CO2) to carbon‐building blocks, which has a huge market demand and increasing annual global production. Despite tremendous research, the conversion of CO2 into valuable fuels and chemicals is still challenging due to the highly inert and diverse CO2 reduction pathways towards high Faradaic efficiency, current density, and stability in the industrialization of ECDRR process. Herein, the most recent developments such as 1) the evaluation of the role of an electrocatalyst according to industrial production demands; 2) the performance of nanostructured electrocatalyst, electrolyte, and devices; 3) advantages and disadvantages of promising metals, such as Au, Ag, and Cu, and single‐atoms, such as Ni, Fe, and Co; and 4) the electrolyte effects, pH effects, and ion effects are described with a vision for ECDRR electrocatalysis towards industrialization. Finally, this review aims to offer forward‐looking, on‐going research/possible activities, together with future perspectives on the ECDRR process from a small‐scale production to industrialization.
Chlorination: An Effective Strategy for High‐Performance Organic Solar Cells
Authors: Zhao Qiaoqiao , Qu Jianfei , He Feng
Published: June 2020

This work summarizes recent developments in polymer solar cells (PSCs) prepared by a chlorination strategy. The intrinsic property of chlorine atoms, the progress of chlorinated polymers and small molecules, and the synergistic effect of chlorination with other methods to elevate solar conversions are discussed. Halogenation of donor–acceptor (D–A) materials is an effective method to improve the performance of PSCs, which mainly affects the push–pull of electrons between donor and acceptor units due to their strong electron‐withdrawing capabilities. Although chlorine is less electronegative than fluorine, it can form very strong noncovalent interactions, such as Cl···S and Cl···π interactions, because its empty 3d orbits can help to accept the electron pairs or π electrons. This synergistic effect of electronegativity together with the empty 3d orbits of chlorine atoms leads to increased intramolecular and intermolecular interactions and a much stronger capability to down‐shift the molecular energy levels. This work is intended to support a better understanding of the chlorination strategy to modify the material properties, and thus improve the performance of solar devices. Eventually, it will provide the research community with a clearer pathway to choose proper substitution methods according to different situations for high and stable solar energy conversion.
Organic Microbial Electrochemical Transistor Monitoring Extracellular Electron Transfer
Authors: Méhes Gábor , Roy Arghyamalya , Strakosas Xenofon , Berggren Magnus , Stavrinidou Eleni , Simon Daniel T.
Published: June 2020

Extracellular electron transfer (EET) denotes the process of microbial respiration with electron transfer to extracellular acceptors and has been exploited in a range of microbial electrochemical systems (MESs). To further understand EET and to optimize the performance of MESs, a better understanding of the dynamics at the microscale is needed. However, the real‐time monitoring of EET at high spatiotemporal resolution would require sophisticated signal amplification. To amplify local EET signals, a miniaturized bioelectronic device, the so‐called organic microbial electrochemical transistor (OMECT), is developed, which includes Shewanella oneidensis MR‐1 integrated onto organic electrochemical transistors comprising poly(3,4‐ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) combined with poly(vinyl alcohol) (PVA). Bacteria are attached to the gate of the transistor by a chronoamperometric method and the successful attachment is confirmed by fluorescence microscopy. Monitoring EET with the OMECT configuration is achieved due to the inherent amplification of the transistor, revealing fast time‐responses to lactate. The limits of detection when using microfabricated gates as charge collectors are also investigated. The work is a first step toward understanding and monitoring EET in highly confined spaces via microfabricated organic electronic devices, and it can be of importance to study exoelectrogens in microenvironments, such as those of the human microbiome.
Skin‐Like Hybrid Integrated Circuits Conformal to Face for Continuous Respiratory Monitoring
Authors: Chen Ying , Liu Fei , Lu Bingwei , Zhang Yingchao , Feng Xue
Published: June 2020

To perform wearable and continuous health monitoring, epidermal electronics for all kinds of sensing have been developed, yet neither organic nor inorganic materials‐based epidermal devices are able to perform the functions like signal collection, processing, transmission, or power supply. Here, a strategy is reported to build skin‐like hybrid integrated circuits (SHICs) with stretchable sensors and commercial chips for long‐term respiratory monitoring. It can independently perform signal acquisition, processing, converting, and wireless transmission with carrying power supply. Thermal theory model is established to characterize the breathing air's interaction with the sensor, which helps in signal analysis. Respiratory monitoring on human body is tested in diverse daily activities including exercising, dining, drinking, and sleeping with a custom‐developed phone application to record and display the respiratory signal. Results show that the SHIC is of high efficiency and accuracy to track the breath patterns continuously in both static and moving scenarios. Furthermore, the SHIC is a feasible and promising platform that can be extended with multiple sensors or actuators in individualized medical applications and physiological study.
Operational Stability Enhancement of Polymeric Organic Field‐Effect Transistors by Amorphous Perfluoropolymers Chemically Anchored to Gate Dielectric Surfaces
Authors: Bulgarevich Kirill , Sakamoto Kenji , Yasuda Takeshi , Minari Takeo , Takeuchi Masayuki
Published: June 2020

Bias‐stress resistance of polymer‐based organic field‐effect transistors (OFETs) is considerably enhanced by coating the gate dielectric surface with an amorphous perfluoropolymer (CYTOP). In bottom‐gate (BG) OFETs offering a relatively simple fabrication process, the CYTOP coating causes a serious problem; that is, thin film formation of organic semiconducting polymers generally fails due to the lyophobic properties of CYTOP. This problem is solved by patterning the CYTOP coating layer with suitable designs. Here, a simple photo‐patterning method is established using CYTOP terminated with amidosilyl functional groups. This method is composed of self‐limited thinning process of CYTOP coating layers, exposure to vacuum ultraviolet light through a photomask, and development. BG/top‐contact OFET arrays are fabricated using poly(2,5‐bis(3‐hexadecylthiophene‐2‐yl)thieno[3,2‐b]thiophene) as the semiconducting polymer. The initial electrical properties and bias‐stress resistance are compared with those of OFETs with octadecyltrichlorosilane (ODTS)‐treated gate dielectrics. The CYTOP‐ and ODTS‐OFETs show approximately the same initial electrical properties with very small device‐to‐device variation, while the CYTOP‐OFETs exhibit much higher intrinsic bias‐stress resistance. Therefore, the spin‐coating combined with the simple photo‐patterning method is a promising technique that can form polymeric organic semiconductor layers on CYTOP layers and produce BG OFETs exhibiting very high operational stability.
Theoretical and Experimental Investigations on the Aggregation‐Enhanced Emission from Dark State: Vibronic Coupling Effect
Authors: Yin Ping‐An , Wan Qing , Niu Yingli , Peng Qian , Wang Zhiming , Li Yuxuan , Qin Anjun , Shuai Zhigang , Tang Ben Zhong
Published: June 2020

Aggregation‐induced/‐enhanced emission (AIE/AEE) has aroused broad interest. The mechanism behind is understood as the aggregation restriction of the nonradiative decay from electronically excited state to the ground state, either through interconversion or through conical intersection, leaving the dipole‐allowed radiative decay channel relatively intact. Here, a report on an AEE phenomenon for 5,10‐diphenylphenazine (DPhPZ) compound is presented, for which the experiment shows to be AEE active but the lowest excited state has been long known to be “dark state,” namely with zero transition dipole with the ground state according to Kasha’s rule. The computational studies demonstrate that the optical emission stems from the “dark state” with emission intensity borrowed from higher‐lying “bright state” through Herzberg–Teller vibronic coupling, and the resultant spectra are in good agreement with the experiment in terms of both line shape and peak position. The vibronic‐coupling‐induced radiative decay and the restricted nonradiative decay synergistically bring about highly efficient luminescence of DPhPZ in the solid phase. The findings open a new avenue for the development of solid‐emissive luminophores.
Ferroelastic‐Domain‐Assisted Mechanical Switching of Ferroelectric Domains in Pb(Zr,Ti)O3 Thin Films
Authors: Yuan Guoliang , Huang Houbing , Li Chen , Liu Di , Cheng Zhihao , Wu Di
Published: June 2020

A recent breakthrough in mechanical polarization switching provides a valuable handle to achieve nanoscale ferroelectric domain control. This flexoelectric switching is usually observed in ultrathin films (≈10 nm or less in thickness), where a large strain gradient is possible. However, from the point of view of device applications, it will be more attractive to achieve mechanical domain switching in thicker films. Here, it is experimentally demonstrated that by introducing ferroelastic a‐domains in PbZr0.1Ti0.9O3 films the potential barrier against 180° c‐domain switching can be greatly decreased, enabling mechanical ferroelectric domain switching in 50 nm thick films by applying a loading force from an atomic force microscope tip. Moreover, these a‐domains are stable in the c‐domain matrix without further mechanical stressing. This makes it possible to create nanoscale domain wall circuitry. These results shed light on the mechanism of domain switching in ferroelectric thin films and may facilitate the design of mechanically controlled novel ferroelectric devices.
Indoor Thin‐Film Photovoltaics: Progress and Challenges
Authors: Li Meng , Igbari Femi , Wang Zhao‐Kui , Liao Liang‐Sheng
Published: June 2020

Energy generation and consumption have always been an important component of social development. Interests in this field are beginning to shift to indoor photovoltaics (IPV) which can serve as power sources under low light conditions to meet the energy needs of rapidly growing fields, such as intelligence gathering and information processing which usually operate via the Internet‐of‐things (IoT). Since the power requirements for this purpose continue to decrease, IPV systems under low light may facilitate the realization of self‐powered high‐tech electronic devices connected through the IoT. This review discusses and compares the characteristics of different types of IPV devices such as those based on silicon, dye, III‐V semiconductors, organic compounds, and halide perovskites. Among them, specific attention is paid to perovskite photovoltaics which may potentially become a high performing IPV system due to the fascinating photophysics of the halide perovskite active layer. The limitations of such indoor application as they relate to the toxicity, stability, and electronic structure of halide perovskites are also discussed. Finally, strategies which could produce highly functional, nontoxic, and stable perovskite photovoltaics devices for indoor applications are proposed.
Estimating rates and patterns of diversification with incomplete sampling: a case study in the rosids
Authors: Sun Miao , Folk Ryan A. , Gitzendanner Matthew A. , Soltis Pamela S. , Chen Zhiduan , Soltis Douglas E. , Guralnick Robert P.
Published: June 2020

Premise

Recent advances in generating large‐scale phylogenies enable broad‐scale estimation of species diversification. These now common approaches typically are characterized by (1) incomplete species coverage without explicit sampling methodologies and/or (2) sparse backbone representation, and usually rely on presumed phylogenetic placements to account for species without molecular data. We used empirical examples to examine the effects of incomplete sampling on diversification estimation and provide constructive suggestions to ecologists and evolutionary biologists based on those results.

Methods

We used a supermatrix for rosids and one well‐sampled subclade (Cucurbitaceae) as empirical case studies. We compared results using these large phylogenies with those based on a previously inferred, smaller supermatrix and on a synthetic tree resource with complete taxonomic coverage. Finally, we simulated random and representative taxon sampling and explored the impact of sampling on three commonly used methods, both parametric (RPANDA and BAMM) and semiparametric (DR).

Results

We found that the impact of sampling on diversification estimates was idiosyncratic and often strong. Compared to full empirical sampling, representative and random sampling schemes either depressed or inflated speciation rates, depending on methods and sampling schemes. No method was entirely robust to poor sampling, but BAMM was least sensitive to moderate levels of missing taxa.

Conclusions

We suggest caution against uncritical modeling of missing taxa using taxonomic data for poorly sampled trees and in the use of summary backbone trees and other data sets with high representative bias, and we stress the importance of explicit sampling methodologies in macroevolutionary studies.
An Interface‐Bridged Organic–Inorganic Layer that Suppresses Dendrite Formation and Side Reactions for Ultra‐Long‐Life Aqueous Zinc Metal Anodes
Authors: Cui Yanhui , Zhao Qinghe , Wu Xiaojun , Chen Xin , Yang Jinlong , Wang Yuetao , Qin Runzhi , Ding Shouxiang , Song Yongli , Wu Junwei , Yang Kai , Wang Zijian , Mei Zongwei , Song Zhibo , Wu Hong , Jiang Zhongyi , Qian Guoyu , Yang Luyi , Pan Feng
Published: June 2020

Aqueous zinc (Zn) batteries (AZBs) are widely considered as a promising candidate for next‐generation energy storage owing to their excellent safety features. However, the application of a Zn anode is hindered by severe dendrite formation and side reactions. Herein, an interfacial bridged organic–inorganic hybrid protection layer (Nafion‐Zn‐X) is developed by complexing inorganic Zn‐X zeolite nanoparticles with Nafion, which shifts ion transport from channel transport in Nafion to a hopping mechanism in the organic–inorganic interface. This unique organic–inorganic structure is found to effectively suppress dendrite growth and side reactions of the Zn anode. Consequently, the Zn@Nafion‐Zn‐X composite anode delivers high coulombic efficiency (ca. 97 %), deep Zn plating/stripping (10 mAh cm−2), and long cycle life (over 10 000 cycles). By tackling the intrinsic chemical/electrochemical issues, the proposed strategy provides a versatile remedy for the limited cycle life of the Zn anode.
A Chiral Naphthyridine Diimine Ligand Enables Nickel‐Catalyzed Asymmetric Alkylidenecyclopropanations
Authors: Braconi Elena , Cramer Nicolai
Published: June 2020

A novel class of chiral naphthyridine diimine ligands (NDI*) readily accessible from C2‐symmetric 2,6‐di‐(1‐arylethyl)anilines is described. The utility of these ligands, particularly one with fluorinated aryl side arms, is demonstrated by a reductive Ni‐catalyzed enantioselective alkylidene transfer reaction from 1,1‐dichloroalkenes to olefins. This transformation provides direct access to a broad range of synthetically valuable alkylidenecyclopropanes in high yields and enantioselectivities.
Dual‐Mode Superresolution Imaging Using Charge Transfer Dynamics in Semiconducting Polymer Dots
Authors: Jiang Yifei , Hu Qiongzheng , Chen Haobin , Zhang Jicheng , Chiu Daniel T. , McNeill Jason
Published: June 2020

In a conjugated polymer‐based single‐particle heterojunction, stochastic fluctuations of the photogenerated hole population lead to spontaneous fluorescence switching. We found that 405 nm irradiation can induce charge recombination and activate the single‐particle emission. Based on these phenomena, we developed a novel class of semiconducting polymer dots that can operate in two superresolution imaging modes. The spontaneous switching mode offers efficient imaging of large areas, with <10 nm localization precision, while the photoactivation/deactivation mode offers slower imaging, with further improved localization precision (ca. 1 nm), showing advantages in resolving small structures that require high spatial resolution. Superresolution imaging of microtubules and clathrin‐coated pits was demonstrated, under both modes. The excellent localization precision and versatile imaging options provided by these nanoparticles offer clear advantages for imaging of various biological systems.
Universal Strategy for Improving the Sensitivity of Detecting Volatile Organic Compounds by Patterned Arrays
Authors: Liu Lu , Xiong Wei , Cui Linfeng , Xue Zhenjie , Huang Chuanhui , Song Qian , Bai Wanqiao , Peng Yage , Chen Xiangyu , Liu Keyan , Zhang Shuwei , Wen Lei , Che Yanke , Wang Tie
Published: June 2020

The diffusion of target analytes is a determining factor for the sensitivity of a given gas sensor. Surface adsorption results in a low‐concentration region near the sensor surface, producing a concentration gradient perpendicular to the surface, and drives a net flux of molecules toward solid reactive reagents on the sensor surface, that is, vertical diffusion. Here, organic semiconductor supramolecules were patterned into micromeshed arrays to integrate vertical and horizontal diffusion pathways. When used as a gas sensor, these arrays have an order of magnitude higher sensitivity than traditional film‐based sensors. The sensor sensitivity ramp down with the increase in coverage density of reactive reagents, yielding two linear regions demarcated by 0.3 coverage, which are identified by the experimental results and simulations. The universal nature of template‐assisted patterning allows adjustments in the composition, size, and shape of the constituent material, including nanofibers, nanoparticles, and molecules, and thus serves to improve the sensitivity of gas sensors for detecting various volatile organic compounds.
Local anaesthetic resistance in a patient with Ehlers‐Danlos syndrome undergoing caesarean section with continuous spinal anaesthesia
Authors: Wloch K. , Simpson M. , Gowrie‐Mohan S.
Published: June 2020

A patient with a diagnosis of Ehlers‐Danlos syndrome was scheduled to undergo elective caesarean section with a combined spinal‐epidural anaesthetic technique. The epidural attempt resulted in an inadvertent dural puncture, and we decided subsequently to place an intrathecal catheter. She required high repeated doses of hyperbaric bupivacaine (32.5 mg over 1 h) through the catheter to establish adequate sensory blockade, together with supplemental analgesic techniques. Soon after the procedure, she recovered motor function rapidly and required further supplemental analgesia. We believe this is the first report of possible local anaesthetic resistance with an intrathecal catheter anaesthetic technique for a patient with Ehlers‐Danlos syndrome. If there is resistance to the first dose of intrathecal local anaesthetic, a general anaesthetic may be the best option for such patients.
A junior doctor’s experience of critical illness: from treating patients to becoming a patient with COVID‐19
Authors: Ramachandran S.
Published: June 2020

When the coronavirus disease 2019 (COVID‐19) pandemic was declared, it was clear that severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) would have far‐reaching impacts on medicine, society and everyday life. As a junior doctor working closely with patients with SARS‐CoV‐2 infection, I was aware of my personal risk of exposure to the virus. I assumed that as a fit and well 26‐year‐old with no comorbidities, if I were to become infected, it was unlikely that COVID‐19 would be severe. However, I became critically unwell following a week of clinical work, necessitating hospital admission, tracheal intubation and mechanical ventilation. I remained mechanically ventilated for 6 days and was then transferred to a medical ward 2 days later. After two further days of rehabilitation, I was discharged home. This reflection is not a junior doctor’s view of how COVID‐19 was managed by the NHS, but a personal view of my illness from ‘the other side of the curtain’. My reflections focus upon the psychological aspects of my experiences, exploring the memories that I formed around the time of critical care, how the fears that I possessed were managed with exceptional communication, and the importance of the wider healthcare team in my recovery.
Design of Highly Reversible Zinc Anodes for Aqueous Batteries Using Preferentially Oriented Electrolytic Zinc
Authors: Faegh Ehsan , Ng Benjamin , Hayman Dillon , Mustain William E.
Published: June 2020

Rechargeable zinc‐based batteries have attracted a growing interest due to their intrinsic safety, low environmental impact and potentially very low cost. However, there still remains significant hurdles to achieve cells of commercial interest. Conventional commercial Zn anodes are formed from large, polycrystalline particles with limited control over the shape and size. In this study, preferentially oriented electrolytic Zn (e‐Zn) particles with hexagonal shape and controlled size (∼100 μm) were synthesized and physically characterized by SEM, XRD and BET techniques. The corrosion, discharge and cycling behavior of e‐Zn particles were analyzed in KOH alkaline media. It was found that preferentially oriented e‐Zn particles with low surface area have lower corrosion than Zn powder and 99 % reduced corrosion rate with respect to polycrystalline Zn wire. Furthermore, e‐Zn electrodes were successfully scaled up and showed remarkable reversibility in symmetric cells at a high rate of 20 mA cm−2 for 640 h. e‐Zn/KOH/MnO2 full cells were also demonstrated with ca. 6 times longer cycle life than Zn powder with a lower H2 gassing rate at 10 % Zn DoD and C/20 rate. In addition, a comparison between alkaline vs. mild acidic electrolyte was made in terms of reversibility and structural changes of preferentially oriented e‐Zn electrodes where superior cycling was observed in ZnSO4 for 2000 h.
Is exam performance in anatomy influenced by teaching with prosected cadavers? An evidence‐based study
Authors: Harris June A. , Adey Tanis L. , McKay Donald W.
Published: June 2020

Introduction

Little empirical evidence substantiates the need to use cadavers to teach anatomy effectively. We investigated the effect of attendance at anatomy laboratories and cadaver use on .anatomy exam performance over a 12‐year period (2006–2007 to 2018–2019) before and after a curricular change (2013–2014).

Materials and methods

Anatomy exam performance data were collected from undergraduate files at Memorial University of Newfoundland, Canada, for 782 medical students over a 12‐year period. Three groups emerged: (i) 6 years of the old curriculum using prosected specimens, N = 376; (ii) 3 years of the new curriculum using prosected specimens, N = 239; (iii) 3 years of the new curriculum using no prosected specimens, N = 240. For the 2018–2019 academic year, laboratory attendance was recorded, N = 80.

Results

The unplanned discontinuation of prosected specimens did not markedly impact anatomy instruction. Student performance under the new and old curricula (p = .0018) and with and without cadavers (p = .0117) is slightly, but significantly, different. Student performance is not associated with the number of missed laboratories (Spearman ρ = 0.145, p = .2).

Discussion

Although use of cadavers and prosected specimens continues in anatomy‐wet laboratories, today's tech‐savvy students want information at their fingertips 24/7. The three factors examined in this study suggest a surprisingly consistent performance on anatomy examinations despite changing conditions. Perhaps medical schools should offer as many quality resources as budgets allow, inform students of their availability and let students decide which learning methods work best for them individually, thus facilitating self‐directed learning.

Conclusion

Consistent exam performance can be achieved using a variety of teaching and learning methods.