bluuebunny/crossref_metadata_2025 huggingface dataset:
Strontium isotopic composition as tracer of weathering processes, a review with respect to James Ross Island, Antarctica
Authors: Míková Jitka
Published: August 2013

Strontium isotopes (87Sr/86Sr) are routinely used to determine sources and mixing relationships in geochemical studies. They have proven to be useful in determining weathering processes and quantifying end-member mixing processes. A number of studies highlight that Sr isotopes represent a powerful tool helping to constrain weathering reactions, weathering rates, flow pathways and mixing scenarios, even when inherent differences in weathering rates of different minerals, and mineral heterogeneity in natural environments may cause difficulties in defining the weathering component of different geochemical systems. Nevertheless, Sr isotopes are useful when combined with other chemical data, to constrain models of water–rock interaction and mixing as well as geochemical processes such as weathering. This paper presents basic information about Sr isotopic system, new analytical developments, summary of recent published studies in constraining the weathering processes, and indicates studies similar to weathering in polar regions. The aim of this paper is to present rationale of using Sr isotopes as tracer of weathering processes on James Ross Island, Antarctica.
Interspecific differences in photosynthetic efficiency and spectral reflectance in two Umbilicaria species from Svalbard during controlled desiccation
Authors: Jupa Radek , Hájek Josef , Hazdrová Jana , Barták Miloš
Published: August 2013

This study aimed to evaluate the effective photosynthetic quantum yield (FPSII) and the Photochemical Reflectance Index (PRI) for assessment of photosynthetic performance of two Umbilicaria lichens during gradual desiccation of their thalli. U. cylindrica andU. decussata exhibited curvilinear relationship (S-shape curve) of decreasing FPSII values with decreasing water potential (WP) of thalli. During initial phase of desiccation (WP from 0 to -10 MPa), no decrease of FPSII was apparent, further desiccation (WP from -10 to -20 MPa) led to fast FPSII decrease from 0.6 to 0.1 indicating strong inhibition of photosynthetic processes. Critical WP at which photosythetic processes are fully inhibited was found bellow -25 MPa in both lichen species. Photochemical Reflectance Index (PRI) exhibited curvilinear increase with thalli desiccation (decreasing WP). At full thallus hydration, the PRI reached the value of -0.18 in both species. Under strong dehydration (WP from -20 to -30 MPa), however, U. cylindrica showed somewhat lower value (-0.04) than U.decussata (-0.02 MPa). PRI to WP relationship is discussed and compared to existing evidence from higher plants and poikilohydric organisms.
Diversity and distribution of tardigrades in soils of Edmonson Point (Northern Victoria Land, continental Antarctica)
Authors: Smykla Jerzy , Iakovenko Nataliia , Devetter Miloslav , Kaczmarek Łukasz
Published: August 2013

This work contributes to the knowledge on distribution, diversity and ecology of the Antarctic soil biota. Different soil habitats from several ice-free coastal sites were sampled along the Victoria Land across 7° of latitude from 71° to 78°S during five austral summer seasons between 2003/04 and 2011/12. In this paper we report preliminary data on soil tardigrades (water bears) from Edmondson Point, Northern Victoria Land. Tardigrades were found to be present in 23 of the 41 examined soil samples (56%). Their presence was associated exclusively with soil samples collected from bryophytes communities and under cyanobacterial mats, whereas they were completely absent in fellfield and ornithogenic soils. Tardigrades were least numerous among all soil micrometazoans, their abundance in the positive samples was very variable and ranged from 3 to 1824 individuals per 100 g of soil DW. High water content seemed to be the major factor determining occurrence of tardigrades in the soils investigated. On the other hand low water content and toxic compounds from penguin guano seemed to act as a strong constraint on their existence in the Antarctic soils. Taxonomic evaluation of the extracted tardigrades revealed presence of only two species belonging to class Eutardigrada: Acutuncus antarcticus (Richters, 1904) and Milnesium antarcticum Tumanov, 2006. While A. antarcticus has already been reported previously as the most widespread and abundant tardigrade across the Victoria Land, the information on M. antarcticum is novel, both for Victoria Land and the continental Antarctica.
Módulos de elasticidade longitudinal e transversal em vigas roliças de madeira de Corymbia citriodora
Authors: Zangiácomo André Luiz , Christoforo André Luis , Lahr Francisco Antonio Rocco
Published: August 2013

Este trabalho objetivou avaliar, com o auxílio do ensaio de flexão estática a três pontos, conduzido de forma não destrutiva, os valores dos módulos de elasticidade longitudinal (E) e transversal (G) em peças roliças estruturais de madeira de Corymbia citriodora, de maneira a se verificar a validade da relação G=E/20 estabelecida pela norma brasileira ABNTNBR 7190:1997 (Projeto de Estruturas de Madeira). As peças testadas (20) possuem comprimento médio de 750 cm, diâmetro médio de 30 cm, teor de umidade de 12% e conicidade média de 5%. Foram realizados dois ensaios de flexão por peça, diferenciados apenas pelas distâncias entre os apoios. No primeiro ensaio, foi utilizada a relação (L/d) entre comprimento (L) e diâmetro (d) das peças igual a vinte e quatro, e no segundo, realizado na sequência, com L/digual a quinze. Os módulos de elasticidade foram obtidos de acordo com o emprego sucessivo da equação da teoria de vigas de Timoshenko, que leva em consideração a influência dos esforços cisalhantes no cálculo dos deslocamentos. Os resultados obtidos entre os módulos de elasticidade longitudinal e transversal foram relacionados pelo método dos mínimos quadrados, sendo encontrada a relação G=E/56, evidenciando, para as peças de madeira investigadas, a divergência de resultados com a norma brasileira.
Memes: formações discursivas que ecoam no ciberespaço
Authors: Souza Carlos Fabiano de
Published: August 2013

O presente artigo propõe uma análise de formações discursivas que figuram como “memes” – em redes sociais – tendo como aporte teórico os escritos de Fiorin (1998) e a Análise de Discurso Crítica (ADC) – teoria do discurso que visa analisar a linguagem como uma prática social e ideológica segundo as concepções de Fairclough (2001a, 2001b; 2003). Para tanto, o estudo parte de considerações iniciais acerca do surgimento do termo cunhado por Richard Dawkins em seu livro O Gene Egoísta (1976) no qual o autor postula a ideia de “meme” – unidade de informação cultural que é replicada de pessoa para pessoa – em analogia ao gene. Além disso, serão consideradas como base de suporte à investigação as concepções de Susan Blackmore (1999) sobre o papel dos “memes” enquanto força poderosa que molda nossa evolução cultural através de ideias copiadas de indivíduo para indivíduo pela imitação. O trabalho culmina com enfoques sobre as implicações do papel desempenhado por componentes mêmicos em ambientes virtuais como forma de representação ideológica das vozes de personagens do mundo real que postam comentários em redes sociais fomentando, assim, discussões que cooperam para a divulgação dos “memes”.
Clinical and diagnostic pathways in pediatric fungal infections
Authors: Castagnola Elio
Published: August 2013

Generally speaking, in pediatrics the patients mostly affected by fungal infections are hematological patients, followed by those with solid tumors, and transplant recipients. Candida infections generally occur just after birth, whereas Aspergillus infections are age-related, and increase their incidence with age. However, among infections, the incidence of bacteremias are still greater than that of mycoses. In pediatrics, in Italy the immunocompromised patients – thus particularly susceptible to fungal infections – are mainly those with severe combined immunodeficiency, chronic mucocutaneous candidiasis, and chronic granulomatous disease. Particular Aspergillus or Scedosporium infections should be considered in peculiar kinds of patients, such as those affected by cystic fibrosis. Finally, different kinds of fungi should be considered in those who come from or spend a lot time in specific areas, such as South America (e.g. coccidioidomycoses, for which differential diagnosis is with tuberculosis).
Appropriate use of antifungal agents
Authors: Castagnola Elio
Published: August 2013

As knowledge increases faster and faster, authorizations for drug use often don’t report the most recent evidence. In addition, trials on pediatric populations are rare: as a consequence, a lot of drugs in pediatrics are prescribed out of their indications. This is called off-label use, if the drug isn’t approved for the treatment of a specific disease, or unauthorized use, if, for example, a dose isn’t written in the summary of product characteristics. These uses aren’t illegal, but physicians should take some steps in order to protect their liability: for example, the hospital should write documents based on shared scientific evidence, where the reasons supporting a choice are explained. Informed consent should be obtained, after an exhaustive explanation, from the parents. There is also the exceptional use, i.e. the use in desperate cases, where no other treatments are possible, but, for example, a study in an animal model has resulted in good outcomes. Even in this case, similar measures should be taken by the physician.
The use of albumin in the complications of cirrhosis: evidence and future perspectives
Authors: Tovoli Alessandra , Zaccherini Giacomo , Napoli Lucia , Ricci Carmen Serena , Tufoni Manuel , Caraceni Paolo
Published: August 2013

The therapeutic use of albumin in cirrhosis dates back to the 50s, when hypoalbuminemia was thought to play a crucial role in the pathophysiology of ascites. Today, while its efficacy in the treatment of ascites is still under investigation, it has been proved that albumin is able to improve patient outcome and survival in some specific complications of cirrhosis, such as the prevention of post-paracentesis circulatory dysfunction and the treatment of spontaneous bacterial peritonitis and hepatorenal syndrome. Beside its oncotic power, albumin carries other biological properties, the so called non-oncotic properties, including transportation and detoxification of several molecules, free radical scavenging, modulation of vascular permeability, activity on the immune system and on the haemostatic balance. Some experimental evidences indicate that not only albumin concentration but also its function is reduced in patients with cirrhosis. However, the clinical implications of such functional abnormalities is still unclear. We here present the available evidence on the use of albumin in cirrhosis and future perspectives.
Histórias de Salvador nos nomes das suas ruas
Authors: Eduardo Dorea Luiz
Published: August 2013

Salvador esconde em seu desordenado contexto urbano, o histórico passado daquela que foi a primeira capital do Brasil. Dentro dos seus limites primitivos, demarcou-se uma praça central e dela partiram as poucas vias à epoca necessárias ao trânsito de pessoas e mercadorias. Cada um desses logradouros recebeu o seu próprio batismo, muitos dos quais ainda hoje se encontram em uso. A pesquisa reunida nesse livro resgata a memória de fatos, acontecimentos e personagens cuja existencia e realidade históricas acham-se registradas nas placas de endereçamento afixadas nas esquinas.
Progression From Presymptomatic to Clinical Type 1 Diabetes After COVID-19 Infection
Authors: Friedl Nadine , Sporreiter Melanie , Winkler Christiane , Heublein Anja , Haupt Florian , Ziegler Anette-Gabriele , Bonifacio Ezio ,   Fr1da Study Group
Published: July 2024

This study examines whether an association exists between COVID-19 infection and progression to clinical diabetes among youth with presymptomatic type 1 diabetes.
Pediatric Complex Chronic Condition System Version 3
Authors: Feinstein James A. , Hall Matt , Davidson Amber , Feudtner Chris
Published: July 2024

Importance

Since implementation of the International Statistical Classification of Diseases, Tenth Revision, Clinical Modification (ICD-10-CM) in the US, thousands of new or related codes have been added to represent clinical conditions. The widely used pediatric complex chronic condition (CCC) system required a major update from version 2 (V2) to version 3 (V3) to capture the range of clinical conditions represented in the ICD-10-CM.

Objective

To update the CCC V3 system, creating V3, with new, missing, or retired codes; to reconceptualize the system’s use of technology codes; and to compare CCC V3 with V2.

Design, Setting, and Participants

This repeated cross-sectional study examined US hospitalization data from the Pediatric Health Information System (PHIS) and the Medicaid Merative MarketScan Research Databases from January 1, 2009, to December 31, 2019, for all patients aged 0 to 18 years. Data were analyzed from March 1, 2023, to April 1, 2024.

Exposures

The CCCs were identified in both data sources using the CCC V2 and V3 systems.

Main Outcomes and Measures

The (1) percentage of pediatric hospitalizations associated with a CCC, (2) numbers of CCC body-system categories per patient, and (3) explanatory power for hospital length of stay and in-hospital mortality were compared over time for V3 vs V2.

Results

Among 7 186 019 hospitalizations within PHIS, 54.3% patients were male, the median age was 4 years (IQR, 1-11 years), and 51.2% were aged 0 to 4 years). The CCC V2 identified 2 878 476 (40.1%) patients as having any CCC compared with 2 753 412 (38.3%) identified by V3. In addition, V2 identified 100 065 (1.4%) patients with transplant status compared with 146 683 (2.0%) by V3, and V2 identified 914 835 (12.7%) as having technology codes compared with 805 585 (11.2%) by V3. The 2 systems were similar in accounting for the number of CCC body-system categories per patient and in explaining variation in hospital length of stay and in-hospital mortality. For both V2 and V3, 10.0% of the variance in hospital length of stay and 12.0% of the variance in in-hospital mortality was explained by the presence of a CCC. Similar patterns were observed when analyzing the 2 999 420 Medicaid Merative MarketScan Research Databases’ hospitalizations (52.3% of patients were male, the median age was 1 year [IQR, 0-12 years], and 62.0% were 0 to 4 years old), except that the percentages of identified CCCs were all lower: V2 identified 758 110 hospitalizations (25.3%) with any CCC compared with 718 100 (23.9%) identified by V3.

Conclusions and Relevance

These results suggest that, moving forward, V3 should be used to identify CCCs, and ongoing, frequent updates to V3, using a transparent, structured process, will enable V3 to accurately reflect the evolving spectrum of clinical conditions represented in the ICD-10-CM.
Interrupting the Psychedelic Experience Through Contextual Manipulation to Study Experience Efficacy
Authors: Roseman Leor , Erritzoe David , Nutt David , Carhart-Harris Robin , Timmermann Christopher
Published: July 2024

This quality improvement study investigates the association of interruptions during psychedelic therapy with ratings of intensity of experience.
In Utero Gene Therapy and its Application in Genetic Hearing Loss
Authors: Kong Chenyang , Yin Ge , Wang Xiaohui , Sun Yu
Published: July 2024

For monogenic genetic diseases, in utero gene therapy (IUGT) shows the potential for early prevention against irreversible and lethal pathological changes. Moreover, animal models have also demonstrated the effectiveness of IUGT in the treatment of coagulation disorders, hemoglobinopathies, neurogenetic disorders, and metabolic and pulmonary diseases. For major alpha thalassemia and severe osteogenesis imperfecta, in utero stem cell transplantation has entered the phase I clinical trial stage. Within the realm of the inner ear, genetic hearing loss significantly hampers speech, cognitive, and intellectual development in children. Nowadays, gene therapies offer substantial promise for deafness, with the success of clinical trials in autosomal recessive deafness 9 using AAV‐OTOF gene therapy. However, the majority of genetic mutations that cause deafness affect the development of cochlear structures before the birth of fetuses. Thus, gene therapy before alterations in cochlear structure leading to hearing loss has promising applications. In this review, addressing advances in various fields of IUGT, the progress, and application of IUGT in the treatment of genetic hearing loss are focused, in particular its implementation methods and unique advantages.
Reversible Alignment of Nanoparticles and Intracellular Vesicles During Magnetic Hyperthermia Experiments
Authors: Fernández‐Afonso Yilian , Ruta Sergiu , Páez‐Rodríguez Amira , van Zanten Thomas S. , Gleadhall Sian , Fratila Raluca M. , Moros María , Morales Maria del Puerto , Satoh Akira , Chantrell Roy W. , Serantes David , Gutiérrez Lucía
Published: July 2024

Heating magnetic nanoparticles (MNPs) with AC (Alternating Current) magnetic fields has received significant attention in recent years, particularly for biomedical uses. However, most studies focus on characterizing the heat release, overlooking the fact that the MNPs in the viscous cell environment constitute a dynamic magnetic colloid whose configuration may evolve over time, particularly if a driving force as the AC field is applied. Aiming to shed light on this matter, in this workthe dynamics of the colloid structure during hyperthermia experiments are studied. By combining various experimental and theoretical tools, it is concluded that the AC field may drive the formation of aligned structures, and the impact that such structures may have on the associated heating is assessed. Remarkably, the results show that those field‐driven structures are highly unstable for small particle sizes, rapidly disassembling upon field removal. Moreover, an analogous behavior in vitro is found, with the AC magnetic field also promoting a reversible alignment of vesicles containing the MNPs within the cells. The results suggest that the observed alignment, both of MNPs and intracellular vesicles, may be a common phenomenon in usual hyperthermia experiments, but unnoticed because of the intrinsic unstable nature of the aligned structures.
Anchoring Multi‐Coordinated Bismuth Metal Atom Sites on Honeycomb‐Like Carbon Rods Achieving Advanced Potassium Storage
Authors: Chen Zhisong , Lin Haoxiang , Tan Yiye , Niu Li , Li Hongyan
Published: July 2024

Carbonaceous materials are recognized for their high conductivity and adaptable structures, making them potential candidates for potassium‐ion batteries (PIBs). Yet, their application has been restricted due to challenges like limited potassium storage and slow kinetics. Addressing these issues, this study presents a novel method by anchoring nitrogen‐oxygen‐coordinated bismuth metal atom sites onto honeycomb‐like carbon rods, termed Bi‐N4‐O2@HCR. This aims to enhance PIB performance by exploiting carbonaceous materials' strengths and mitigating their limitations. Through comprehensive experiments and theoretical simulations, it is found that Bi‐N4‐O2 sites enrich potassium storage and facilitate potassium ion migration, thus improving transport efficiency and reaction kinetics. The resulting anode showcased rapid and durable potassium storage, with a remarkable capacity of 190.7 mAh g−1 at 30 A g−1 and maintaining 192.2 mAh g−1 over 4200 cycles at 5 A g−1, outperforming many existing carbon anodes. Additionally, in full cell tests, it exhibited excellent rate performance and ultra‐long cycle life, sustaining up to 8000 cycles with a stable capacity of 88.9 mAh g−1 at 5 A g−1. This research underscores the significance of incorporating unique metal sites on carbon substrates to advance battery technology.
Enzyme‐Responsive Polyion Complex Nanoparticles of Cationic Antimicrobials for Activatable Antibacterial Therapy
Authors: Zhang Bo , Lu Derong , Wang Dennis Bao Rong , Kok Zhi Yuan , Chan‐Park Mary B. , Duan Hongwei
Published: July 2024

A self‐assembled “caging” strategy is presented for the safe delivery of potent cationic antimicrobials that suffer from non‐specific toxicity for the effective treatment of in vivo systemic bacterial infection. The key development here is a new block copolymer consisting of a poly(ethylene glycol) (PEG) stealth block and an anionic and lipase‐degradable block of poly(ɛ‐caprolactone) (PCL) and phosphonic acid‐bearing methacrylate copolymer, synthesized by hybrid copolymerization of methacrylate and cyclic esters. The anionic blocks electrostatically interact with cationic antimicrobials to form neutrally charged polyion complexes with the PEG blocks on the surface. The PCL component imparts the nanocomplex with biodegradability by bacterial secretory lipase. In the proof‐of‐concept study, cationic polyimidazolium that shows excellent antibacterial activity but severe toxicity is packaged by the block copolymer into nanocomplexes, which are stable in complex environments of high salt and protein concentrations and released the antimicrobials upon degradation of the copolymer by bacteria‐secreted lipase. The “caging” formulation of polyimidazolium eliminated its toxicity and led to highly effective bactericidal performance comparable to free polyimidazolium. This caging strategy does not require sophisticated chemical modification of cationic antimicrobials, offering a broadly applicable formulation strategy to overcome their common toxicity issue that has become a primary translational barrier.
Exosomes from Hypoxia Preconditioned Muscle‐Derived Stem Cells Enhance Cell‐Free Corpus Cavernosa Angiogenesis and Reproductive Function Recovery
Authors: Peng Tianwen , Chai Muyuan , Chen Zhicong , Wu Man , Li Xiaomin , Han Feixue , Chen Shuyan , Liao Chen , Yue Ming , Song You‐Qiang , Wu Hongkai , Tian Long , An Geng
Published: July 2024

Tissue engineering for penile corpora cavernosa defects requires microvascular system reconstruction.GelMA hydrogels show promise for tissue regeneration. However, using stem cells faces challenges such as immune rejection, limited proliferation and differentiation, and biosafety concerns. Therefore, acellular tissue regeneration may avoid these issues. Exosomes are used from muscle‐derived stem cells (MDSCs) to modify 3D‐printed hydrogel scaffolds for acellular tissue regeneration. Hypoxia‐preconditioned MDSC‐derived exosomes are obtained to enhance the therapeutic effect. In contrast to normoxic exosomes (N‐Exos), hypoxic exosomes (H‐Exos) are found to markedly enhance the proliferation, migration, and capillary‐like tube formation of human umbilical vein endothelial cells (HUVECs). High‐throughput sequencing analysis of miRNAs isolated from both N‐Exos and H‐Exos revealed a significant upregulation of miR‐21‐5p in H‐Exos following hypoxic preconditioning. Further validation demonstrated that the miR‐21‐5p/PDCD4 pathway promoted the proliferation of HUVECs. Epigallocatechin gallate (EGCG) is introduced to improve the mechanical properties and biocompatibility of GelMA hydrogels. EGCG‐GelMA scaffolds loaded with different types of Exos are transplanted to repair rabbit penile corpora cavernosa defects, observed the blood flow and repair status of the defect site through color Doppler ultrasound and magnetic resonance imaging, and ultimately restored the rabbit penile erection function and successfully bred offspring. Thus, acellular hydrogel scaffolds offer an effective treatment for penile corpora cavernosa defects.
Enantioselective Surface‐Enhanced Raman Scattering by Chiral Au Nanocrystals with Finely Modulated Chiral Fields and Internal Standards
Authors: Tian Yu , Wu Fengxia , Lv Xiali , Luan Xiaoxi , Li Fenghua , Xu Guobao , Niu Wenxin
Published: July 2024

The chiral discrimination of enantiomers is crucial for drug screening and agricultural production. Surface‐enhanced Raman scattering (SERS) is proposed for discriminating enantiomers benefiting from chiral plasmonic materials. However, the mechanism of enantioselective SERS is unclear, and fluctuating SERS intensities may result in errors. Herein, this work demonstrates a reliable SERS substrate using chiral Au nanocrystals with finely modulated chiral fields and internal standards. Chiral electromagnetic fields are enhanced after modulation, which is conducive to increasing the difference in the enantiomeric SERS intensity, as evidenced by the experimental and simulation results. Furthermore, the SERS stability is improved by the corrective effect of the internal standards, and the relative standard deviation is significantly reduced. Using finely modulated chiral fields and internal standards, L‐ and D‐phenylalanine exhibit a stable six times difference in SERS ratio. Theoretical simulations reveal that linearly polarized light can also excite the chiral fields of chiral Au nanocrystals, indicating non‐chiral far‐field light is converted into chiral near‐field sources by chiral Au nanocrystals. Thus, the mechanism of enantioselective SERS can be elucidated by the scattering difference of chiral molecules in chiral near fields. This study will pave the way for the development of enantioselective SERS and related chiroptical technologies.
Conjugation‐Broken Dimer Acceptors Enable High‐Efficiency, Stable, and Flexibility‐Robust Organic Solar Cells
Authors: Li Yun , Mei Le , Ge Zhongwei , Liu Chunhui , Song Jiali , Man Yuheng , Gao Jiaxing , Zhang Jianqi , Tang Zheng , Chen Xian‐Kai , Sun Yanming
Published: July 2024

Dimer acceptors in organic solar cells (OSCs) offer distinct advantages, including a well‐defined molecular structure and excellent batch‐to‐batch reproducibility. Their high glass transition temperature (Tg) aids in achieving an optimal kinetic morphology, thereby enhancing device stability. Currently, most of dimer acceptor materials are linked with conjugated units in order to obtain high power conversion efficiencies (PCEs). In this study, different from previous works on conjugation‐linked dimer acceptors, a novel series of dimer acceptors are synthesized (named T1, T4, T6, and T12), each linked with different flexible alkyl linkers, and investigated their PCEs, device stability, and flexibility robustness. When blended with PM6, the T6‐based device achieves a PCE of 17.09%, comparable to the fully conjugated T0‐based device's PCE of 17.12%. The molecular dynamics simulations and density functional theory calculations suggested that flexible conjugation‐broken linkers (FCBLs) promote intermolecular electronic couplings, thereby maintaining good electron mobilities of dimer acceptors. Notably, the T6‐based device exhibits impressive long‐term stability with a T80 lifetime of 1427 h, while in the T0‐based device, T80 is only 350 h. The present work has thus established the relationship between the length of flexible alkyl linkers in such dimer acceptors and the performance and stability of OSCs, which is important to further designing new materials for the fabrication of efficient and stable OSCs.
Infrared Interlayer Excitons in Twist‐Free MoTe2/MoS2 Heterobilayers
Authors: Ju Qiankun , Cai Qian , Jian Chuanyong , Hong Wenting , Sun Fapeng , Wang Bicheng , Liu Wei
Published: July 2024

Excitonic devices based on interlayer excitons in van der Waals heterobilayers are a promising platform for advancing photoelectric interconnection telecommunications. However, the absence of exciton emission in the crucial telecom C‐band has constrained their practical applications. Here, this limitation is addressed by reporting exciton emission at 0.8 eV (1550 nm) in a chemically vapor‐deposited, strictly aligned MoTe2/MoS2 heterobilayer, resulting from the direct bandgap transitions of interlayer excitons as identified by momentum–space imaging of their electrons and holes. The decay mechanisms dominated by direct radiative recombination ensure constant emission quantum yields, a basic demand for efficient excitonic devices. The atomically sharp interface enables the resolution of two narrowly‐splitter transitions induced by spin–orbit coupling, further distinguished through the distinct Landé g‐factors as the fingerprint of spin configurations. By electrical control, the double transitions coupling into opposite circularly‐polarized photon modes, preserve or reverse the helicities of the incident light with a degree of polarization up to 90%. The Stark effect tuning extends the emission energy range by over 150 meV (270 nm), covering the telecom C‐band. The findings provide a material platform for studying the excitonic complexes and significantly boost the application prospects of excitonic devices in silicon photonics and all‐optical telecommunications.
Ultralow‐Frequency Tip‐Enhanced Raman Scattering Discovers Nanoscale Radial Breathing Mode on Strained 2D Semiconductors
Authors: Cao Mao‐Feng , Peng Xiao‐Hui , Zhao Xiao‐Jiao , Bao Yi‐Fan , Xiao Yuan‐Hui , Wu Si‐Si , Wang Jun , Lu Yao , Wang Miao , Wang Xiang , Lin Kai‐Qiang , Ren Bin
Published: July 2024

Collective excitations including plasmons, magnons, and layer‐breathing vibration modes emerge at an ultralow frequency (<1 THz) and are crucial for understanding van der Waals materials. Strain at the nanoscale can drastically change the property of van der Waals materials and create localized states like quantum emitters. However, it remains unclear how nanoscale strain changes collective excitations. Herein, ultralow‐frequency tip‐enhanced Raman spectroscopy (TERS) with sub‐10 nm resolution under ambient conditions is developed to explore the localized collective excitation on monolayer semiconductors with nanoscale strains. A new vibrational mode is discovered at around 12 cm−1 (0.36 THz) on monolayer MoSe2 nanobubbles and it is identified as the radial breathing mode (RBM) of the curved monolayer. The correlation is determined between the RBM frequency and the strain by simultaneously performing deterministic nanoindentation and TERS measurement on monolayer MoSe2. The generality of the RBM in nanoscale curved monolayer WSe2 and bilayer MoSe2 is demonstrated. Using the RBM frequency, the strain of the monolayer MoSe2 on the nanoscale can be mapped. Such an ultralow‐frequency vibration from curved van der Waals materials provides a new approach to study nanoscale strains and points to more localized collective excitations to be discovered at the nanoscale.
Engineering of Reversibly Cross‐Linked Elastomers Toward Flexible and Recyclable Elastomer/Carbon Fiber Composites with Extraordinary Tearing Resistance
Authors: Wang Xiaohan , Sun Junqi
Published: July 2024

Carbon fiber (CF)‐reinforced polymers (CFRPs) demonstrate potential for use in personal protective equipment. However, existing CFRPs are typically rigid, nonrecyclable, and lack of tearing resistance. In this study, flexible, recyclable, and tearing resistant polyurethane (PU)‐CF composites are fabricated through complexation of reversibly cross‐linked PU elastomer binders with CF fabrics. The PU‐CF composites possess a high strength of 767 MPa and a record‐high fracture energy of 2012 kJ m−2. The high performance of the PU‐CF composites originates from the well‐engineered PU elastomer binders that are obtained by cross‐linking polytetrahydrofuran chains with in situ‐formed nanodomains composed of hierarchical supramolecular interactions of hydrogen and coordination bonds. When subjected to tearing, the force concentrated on the damaged regions of the PU‐CF composites can be effectively distributed to a wider area through the PU binders, leading to a significantly enhanced tearing resistance of the composites. The strong interfacial adhesion between PU binders and the CF fabrics enables the fracture of the CF in bundles, thereby significantly enhancing the strength and fracture energy of the composites. Because of the dynamic nature of the PU elastomer binders, the PU‐CF composites can be recycled through the dissociation of the PU elastomer binders.
Activation of the cGAS‐STING‐IRF3 Axis by Type I and II Interferons Contributes to Host Defense
Authors: Tong Zhen , Zou Jia‐Peng , Wang Su‐Yun , Luo Wei‐Wei , Wang Yan‐Yi
Published: July 2024

Interferons (IFNs) activate JAK‐STAT pathways to induce downstream effector genes for host defense against invaded pathogens and tumors. Here both type I (β) and II (γ) IFNs are shown that can activate the transcription factor IRF3 in parallel with STAT1. IRF3‐deficiency impairs transcription of a subset of downstream effector genes induced by IFN‐β and IFN‐γ. Mechanistically, IFN‐induced activation of IRF3 is dependent on the cGAS‐STING‐TBK1 axis. Both IFN‐β and IFN‐γ cause mitochondrial DNA release into the cytosol. In addition, IFNs induce JAK1‐mediated tyrosine phosphorylation of cGAS at Y214/Y215, which is essential for its DNA binding activity and signaling. Furthermore, deficiency of cGAS, STING, or IRF3 impairs IFN‐β‐ or IFN‐γ‐mediated antiviral and antitumor activities. The findings reveal a novel IRF3 activation pathway parallel with the canonical STAT1/2 activation pathways triggered by IFNs and provide an explanation for the pleiotropic roles of the cGAS‐STING‐IRF3 axis in host defense.
Tailoring Coherent Microwave Emission from a Solid‐State Hybrid System for Room‐Temperature Microwave Quantum Electronics
Authors: Wang Kaipu , Wu Hao , Zhang Bo , Yao Xuri , Zhang Jiakai , Oxborrow Mark , Zhao Qing
Published: July 2024

Quantum electronics operating in the microwave domain are burgeoning and becoming essential building blocks of quantum computers, sensors, and communication devices. However, the field of microwave quantum electronics has long been dominated by the need for cryogenic conditions to maintain delicate quantum characteristics. Here, a solid‐state hybrid system, constituted by a photo‐excited pentacene triplet spin ensemble coupled to a dielectric resonator, is reported for the first time capable of both coherent microwave quantum amplification and oscillation at X band via the masing process at room temperature. By incorporating external driving and active dissipation control into the hybrid system, efficient tuning of the maser emission characteristics at ≈9.4 GHz is achieved, which is key to optimizing the performance of the maser device. The work not only pushes the boundaries of the operating frequency and functionality of the existing pentacene masers but also demonstrates a universal route for controlling the masing process at room temperature, highlighting opportunities for optimizing emerging solid‐state masers for quantum information processing and communication.
Unlocking Nile tilapia (Oreochromis niloticus Linn., 1758) selective breeding programmes in Uganda through geographical genetic structure mapping
Authors: Tibihika Papius Dias , Aruho Cassius , Namulawa Victoria , Ddungu Richard , Atukunda Gertrude , Aanyu Margaret , Nkambo Mujibu , Vijayan Thapasya , Kwikiriza Gerald , Curto Manuel , Meimberg Harald
Published: July 2024

Nile tilapia (Oreochromis niloticus), native to Africa and the Levant, is an important species for both aquaculture and capture fisheries. Despite these attributes, Nile tilapia has been negatively impacted by anthropogenic activities ranging from overfishing and habitat destruction to translocations. These human‐mediated activities have threatened the genetic evolutionary integrity of native populations of Nile tilapia and congeneric species through admixture, demographic bottlenecks and introgressive hybridization. In this context, the genetic contrast between farmed/bred strains and wild Nile tilapia populations in the major lakes of Uganda remains understudied. Understanding the genetic structure of Nile tilapia populations in the major water bodies of Uganda (lakes Victoria, Kyoga, Edward, George, Albert and Nile River) is a key resource to guide selective breeding programmes, thus minimizing the effects of maladaptation under both aquaculture and natural stocks. Although the population genetics of Nile tilapia in Uganda's major lakes have been studied, this was based on limited sampling scope, especially in the wild, and the key information on the species could have been overlooked. We fill this knowledge gap by genotyping 756 Nile tilapia individuals from multiple populations for each major water body of Uganda using a panel of 34 microsatellite loci based on the microsatellite genotyping‐by‐sequencing (SSR‐GBS) technique. The results indicate two discrete gene pools/stocks: the Edward‐George system and the Albert‐Kyoga system‐Victoria. Evidence of loss of genetic diversity and admixture of some Nile tilapia stocks was found, most likely resulting from anthropogenic perturbations. This study contributes useful information key for understanding the potential Nile tilapia broodstock sources for selective breeding programmes, aimed at improving aquaculture production in Uganda.
Expanding the clinical phenotype and variant spectrum associated with RFX7
Authors: Sisroe Talia , Santos Attila Dos , Rippert Alyssa L. , Gray Christopher , Skraban Cara M. , Nelson Beverly , Tefft Sarah , Helbig Ingo , Li Dong , Bhoj Elizabeth J. , Sobering Andrew K.
Published: July 2024

RFX7 encodes a transcription factor that is ubiquitously expressed and important for neural development. Haploinsufficiency of RFX7 is associated with intellectual disability, developmental delay, and diverse malformations of brain structures. Currently, there are only 16 clinically described individuals who have variants in RFX7. A recognizable pattern of malformation associated with mutation in RFX7 has not yet been uncovered. Here we describe the phenotypic presentation of two additional individuals who have novel de novo variants in RFX7. One of the individuals we describe is from an under‐represented Afro‐Caribbean population.
Successful use of methylene blue for catecholamine‐refractory vasoplegic shock due to metformin intoxication: A case report and literature review
Authors: Takahashi Yuji , Nakano Hidehiko , Motoki Maiko , Wakimoto Yuji , Ikechi Daisuke , Koyama Yasuaki , Hashimoto Hideki
Published: July 2024

Background

Severe metformin intoxication can lead to lactic acidosis and vasoplegic shock, for which the optimal management strategy remains uncertain, especially in cases of severe circulatory collapse.

Case Presentation

A 45‐year‐old diabetic woman on metformin therapy presented with impaired consciousness and seizures. She had experienced a cardiac arrest and undergone extracorporeal cardiopulmonary resuscitation. Blood gas analysis showed severe lactic acidosis. A 71‐g metformin packet was found at the patient's home, suggesting an overdose. Despite extracorporeal support and blood purification, severe lactic acidosis and hypotension persisted. Methylene blue was administered 32 h from the onset, which improved her metabolic and circulatory status. We examined her blood sample throughout the case to check the transition of metformin blood concentration.

Conclusion

Methylene blue may be beneficial for severe metformin toxicity, regardless of the blood concentration of metformin and the time since intoxication. However, further research is needed to establish its optimal use and effectiveness.
Strong Enhancement in Cobalt(II)‐TPMA Aqueous Hydrogen Photosynthesis through Intramolecular Proton Relay
Authors: Droghetti Federico , Begato Federico , Raulin Melvin , Musiu Gioia , Licini Giulia , Natali Mirco , Zonta Cristiano
Published: July 2024

Photosynthetic hydrogen generation by cobalt(II) tris(2‐pyridylmethyl)amine (TPMA) complexes is mainly limited by protonation kinetics and decomposition routes involving demetallation. In the present work we have explored the effects of both proton shuttles and improved rigidity on the catalytic ability of cobalt(II) TPMA complexes. Remarkably, we demonstrate that, while a small enhancement in the catalytic performance is attained in a rigid cage structure, the introduction of ammonium groups as proton transfer relays in close proximity to the cobalt center allows to reach a 4‐fold increase in the quantum efficiency of H2 formation, and a surprising 22‐fold gain in the maximum turnover number, at low catalyst concentration. The beneficial role of the ammonium relays in promoting faster intramolecular proton transfer to the reduced cobalt center is documented by transient absorption spectroscopy, showcasing the great relevance of tuning the catalyst periphery to achieve efficient catalysis of solar fuel formation.
Molecular Recognition in Mechanochemistry: Insights from Solid‐State NMR Spectroscopy
Authors: Quaranta Calogero , d'Anciães Almeida Silva Igor , Moos Sven , Bartalucci Ettore , Hendrickx Leeroy , Fahl Benjamin M. D. , Pasqualini Claudia , Puccetti Francesco , Zobel Mirijam , Bolm Carsten , Wiegand Thomas
Published: July 2024

Molecular‐recognition events are highly relevant in biology and chemistry. In the present study, we investigated such processes in the solid state under mechanochemical conditions using the formation of racemic phases upon reacting enantiopure entities as example. As test systems, α‐(trifluoromethyl)lactic acid (TFLA) and the amino acids serine and alanine were used. The effects of ball‐milling and resonant acoustic mixing (RAM) on the formation of racemic phases were probed by using solid‐state Nuclear Magnetic Resonance (NMR) spectroscopy. In a mixer mill, a highly efficient and fast racemic phase formation occurred for both TFLA and the two amino acids. RAM led to the racemic phase for TFLA also, and this process was facilitated upon employing pre‐milled enantiopure entities. In contrast, under comparable conditions RAM did not result in the formation of racemic phases for serine and alanine.
Mixed Crystalline Covalent Heptazine Frameworks with Built‐in Heterojunction Structures towards Efficient Photocatalytic Formic Acid Dehydrogenation
Authors: Cheng Cheng , Zhang Siquan , Zhang Jin , Guan Lijiang , El‐Khouly Mohamed E. , Jin Shangbin
Published: July 2024

Covalent heptazine frameworks (CHFs) are widely utilized in the recent years as potential photocatalysts. However, their limited conjugated structures, low crystallinity and small surface areas have restricted the practical photocatalysis performance. Along this line, we report herein the synthesis of a kind of mixed crystalline CHF (m‐CHF‐1) with built‐in heterojunction structure, which can efficiently catalyze the formic acid dehydrogenation by visible light driven photocatalysis. The m‐CHF‐1 is synthesized from 2,5,8‐triamino‐heptazine and dicyanobenzene (DCB) in the molten salts, in which DCB plays as organic molten co‐solvent to promote the rapid and ordered polymerization of 2,5,8‐triamino‐heptazine. The m‐CHF‐1 is formed by embedding phenyl‐linked heptazine (CHF−Ph) units in the poly(heptazine imide) (PHI) network similar to doping. The CHF−Ph combined with PHI form an effective type II heterojunction structure, which promote the directional transfer of charge carriers. And the integration of CHF−Ph makes m‐CHF‐1 have smaller exciton binding energy than pure PHI, the charge carriers are more easily dissociated to form free electrons, resulting in higher utilization efficiency of the carriers. The largest hydrogen evolution rate reaches a value of 42.86 mmol h−1 g−1 with a high apparent quantum yield of 24.6 % at 420 nm, which surpasses the majority of other organic photocatalysts.
Mechanochemically Promoted Functionalization of Postconsumer Poly(Methyl Methacrylate) and Poly(α‐Methylstyrene) for Bulk Depolymerization
Authors: Young James B. , Goodrich Sofia L. , Lovely James A. , Ross Madison E. , Bowman Jared I. , Hughes Rhys W. , Sumerlin Brent S.
Published: July 2024

We describe a methodology of post‐polymerization functionalization to enable subsequent bulk depolymerization to monomer by utilizing mechanochemical macro‐radical generation. By harnessing ultrasonic chain‐scission in the presence of N‐hydroxyphthalimide methacrylate (PhthMA), we successfully chain‐end functionalize polymers to promote subsequent depolymerization in bulk, achieving up to 82 % depolymerization of poly(methyl methacrylate) (PMMA) and poly(α‐methylstyrene) (PAMS) within 30 min. This method of depolymerization yields a high‐purity monomer that can be repolymerized. Moreover, as compared to the most common methods of depolymerization, this work is most efficient with ultra‐high molecular weight (UHMW) polymers, establishing a method with the potential to address highly persistent, non‐degradable all‐carbon backbone plastic materials. Lastly, we demonstrate the expansion of this depolymerization method to commercial cell cast PMMA, achieving high degrees of depolymerization from post‐consumer waste. This work is the first demonstration of applying PhthMA‐promoted depolymerization strategies in homopolymer PMMA and PAMS prepared by conventional polymerization methods.
Caffeic acid and its derivative caffeic acid phenethyl ester as potential therapeutic compounds for cardiovascular diseases: A systematic review
Authors: Nasimi Shad Arya , Akhlaghipour Iman , Babazadeh Baghan Atefeh , Askari Vahid Reza , Baradaran Rahimi Vafa
Published: July 2024

Cardiovascular diseases (CVDs) contribute to major public health issues. Some studies have found that caffeic acid (CA) and caffeic acid phenethyl ester (CAPE) may effectively prevent or treat CVDs. However, there is a major need to sum up our current understanding of the possible beneficial or detrimental effects of CA and CAPE on CVDs and related mechanisms. Therefore, this study aimed to summarize the data on this topic. A methodical search was carried out on key databases, including Pubmed, Google Scholar, Scopus, and Web of Science, from the beginning to June 2024. Studies were then assessed for eligibility based on inclusion and exclusion criteria. Treatment with CA and CAPE significantly and positively affected cardiovascular health in various aspects, including atherosclerotic diseases, myocardial infarction, hypertension, cardiac arrhythmias, and hypercoagulation state. Several mechanisms were proposed to mediate these effects, including transcription factors and signaling pathways associated with antioxidant, cytostatic, and anti‐inflammatory processes. CA and CAPE were found to have several beneficial effects via multiple mechanisms during the prevention and treatment of various CVDs. However, these promising effects were only reported through in vitro and animal studies, which reinforces the need for further evaluation of these effects via human clinical investigations.