Rising utilization of stable isotopes in tree rings for climate change and forest ecology

Analyses of stable isotopes(C,O,H)in tree rings are increasingly important cross-disciplinary programs.The rapid development in this field documented in an increasing number of publications requires a comprehensive review.This study includes a bibliometric analysis-based review to better understand research trends in tree ring stable isotope research.Overall,1475 publications were selected from the Web of Science Core Collection for 1974-2023.The findings are that:(1)numbers of annual publications and citations increased since 1974.From 1974 to 1980,there were around two relevant publications per year.However,from 2020 to 2022,this rose sharply to 109 publications per year.Likewise,average article citations were less than four per year before 1990,but were around four per article per year after 2000;(2)the major subjects using tree ring stable isotopes include forestry,geosciences,and environmental sciences,contributing to 42.5%of the total during 1974-2023;(3)the top three most productive institutions are the Chinese Academy of Sciences(423),the Swiss Federal Institute for Forest,Snow and Landscape Research(227),and the University of Arizona(204).These achievements result from strong collaborations;(4)review papers,for example,(Dawson et al.,Annu Rev Ecol Syst 33:507-559,2002)and(McCarroll and Loader,Quat Sci Rev 23:771-801,2004),are among the most cited,with more than 1000 citations;(5)tree ring stable isotope studies mainly focus on climatology and ecology,with atmospheric CO_(2) one of the most popular topics.Since 2010,precipitation and drought have received increasing attention.Based on this analysis,the research stages,key findings,debated issues,limitations and direc-tions for future research are summarized.This study serves as an important attempt to understand the progress on the use of stable isotopes in tree rings,providing scientific guid-ance for young researchers in this field.

Highly Sensitive Ultrathin Flexible Thermoplastic Polyurethane/Carbon Black Fibrous Film Strain Sensor with Adjustable Scaffold Networks

In recently years,high-performance wearable strain sensors have attracted great attention in academic and industrial.Herein,a conductive polymer composite of electrospun thermoplastic polyurethane(TPU)fibrous film matrix-embedded carbon black(CB)particles with adjustable scaffold network was fabricated for high-sensitive strain sensor.This work indicated the influence of stereoscopic scaffold network structure built under various rotating speeds of collection device in electrospinning process on the electrical response of TPU/CB strain sensor.This structure makes the sensor exhibit combined characters of high sensitivity under stretching strain(gauge factor of 8962.7 at 155%strain),fast response time(60 ms),outstanding stability and durability(>10,000 cycles)and a widely workable stretching range(0–160%).This high-performance,wearable,flexible strain sensor has a broad vision of application such as intelligent terminals,electrical skins,voice measurement and human motion monitoring.Moreover,a theoretical approach was used to analyze mechanical property and a model based on tunneling theory was modified to describe the relative change of resistance upon the applied strain.Meanwhile,two equations based from this model were first proposed and offered an effective but simple approach to analyze the change of number of conductive paths and distance of adjacent conductive particles.

Ni Flower/MXene-Melamine Foam Derived 3D Magnetic/Conductive Networks for Ultra-Efficient Microwave Absorption and Infrared Stealth

The development of multifunctional and efficient electromagnetic wave absorbing materials is a challenging research hotspot.Here,the magnetized Ni flower/MXene hybrids are successfully assembled on the surface of melamine foam(MF)through electrostatic self-assembly and dip-coating adsorption process,realizing the integration of microwave absorption,infrared stealth,and flame retardant.Remarkably,the Ni/MXene-MF achieves a minimum reflection loss(RLmin)of−62.7 dB with a corresponding effective absorption bandwidth(EAB)of 6.24 GHz at 2 mm and an EAB of 6.88 GHz at 1.8 mm.Strong electromagnetic wave absorption is attributed to the three-dimensional magnetic/conductive networks,which provided excellent impedance matching,dielectric loss,magnetic loss,interface polarization,and multiple attenuations.In addition,the Ni/MXene-MF endows low density,excellent heat insulation,infrared stealth,and flame-retardant functions.This work provided a new development strategy for the design of multifunctional and efficient electromagnetic wave absorbing materials.

Correction to: Ni Flower/MXene-Melamine Foam Derived 3D Magnetic/Conductive Networks for Ultra-Efficient Microwave Absorption and Infrared Stealth

The original version of this article unfortunately contained some mistakes.The corrections are updated as follows:Error 1:We found that Equations 3,4 and 6 were wrong in the published paper:Error 2:In the page 7,“Since N Ni/MXene-MF possessed numer-ous heterogeneous interfaces and abundant functional groups,the dielectric loss mechanism was explored.”

Large Scale Mass Movements Triggered by the Kashmir Earthquake 2005,Pakistan

The SPOT image analysis in Muzaffarabad Azad Kashmir,northwest Himalayas,Pakistan reveals that the Kashmir earthquake 2005 triggered a number of coseismic mass movements along the hanging wall block of the Muzaffarabad Fault.The Neelidandi and Langarpura rock falls have been identified as two major reactivated mass movements with an estimated volume of 3.1 × 106m3and 5.76 × 106m3,respectively.The Neelidandi and Langarpura mass movements were initiated during earthquake in the direction of northwest-southeast extension and northeastsouthwest directed thrusting,respectively.The Neelidandi rock fall occurred in sheared cherty dolomites and limestones of the Cambrian Muzaffarabad Formation,whereas the Langarpura rock fall occurred in alternating clays,shales,claystones,siltstones and sandstones of the Miocene Murree Formation.These rock units along the fault are highly fractured and jointed.The geotechnical maps and geological longitudinal profiles show the relationship between the geometrical characteristics and mechanism of these mass movements.Their characteristics were analyzed according to the role of topographic,seismic,geological and tectonic factors.The steep topography,sheared rocks,lithology,coseismic uplift and strong ground shaking of the hanging wall block along Muzaffarabad Fault facilitated the gravity collapse of these mass movements.

Jejunitis and brown bowel syndrome with multifocal carcinogenesis of the small bowel

This is the first report describing a case where prolonged,severe malabsorption from brown bowel syndrome progressed to multifocally spread small bowel adenocarcinoma. This case involves a female patient who was initially diagnosed with chronic jejunitis associated with primary diffuse lymphangiectasia at the age of 26 years. The course of the disease was clinically,endoscopically,and histologically followed for 21 years until her death at the age 47 due to multifocal,metastasizing adenocarcinoma of the small bowel. Multiple lipofuscin deposits(so-called brown bowel syndrome) and severe jejunitis were observed microscopically,and sections of the small bowel showed dense lymphoplasmacytic infiltration of the lamina propria as well as blocked lymphatic vessels. After several decades,multifocal nests of adenocarcinoma cells and extensive,flat,neoplastic mucosal proliferations were found only in the small bowel,along with a loss of the mismatch repair protein MLH1 as a long-term consequence of chronic jejunitis with malabsorption. No evidence was found for hereditary nonpolyposis colon carcinoma syndrome. This article demonstrates for the first time multifocal carcinogenesis in the small bowel in a malabsorption syndrome in an enteritis-dysplasia-carcinoma sequence.

Domain Decomposition of an Optimal Control Problem for Semi-Linear Elliptic Equations on Metric Graphs with Application to Gas Networks

We consider optimal control problems for the flow of gas in a pipe network. The equations of motions are taken to be represented by a semi-linear model derived from the fully nonlinear isothermal Euler gas equations. We formulate an optimal control problem on a given network and introduce a time discretization thereof. We then study the well-posedness of the corresponding time-discrete optimal control problem. In order to further reduce the complexity, we consider an instantaneous control strategy. The main part of the paper is concerned with a non-overlapping domain decomposition of the semi-linear elliptic optimal control problem on the graph into local problems on a small part of the network, ultimately on a single edge.

Analysis of Electronic Circuits with the Signal Flow Graph Method

In this work a method called “signal flow graph (SFG)” is presented. A signal-flow graph describes a system by its signal flow by directed and weighted graph;the signals are applied to nodes and functions on edges. The edges of the signal flow graph are small processing units, through which the incoming signals are processed in a certain form. In this case, the result is sent to the outgoing node. The SFG allows a good visual inspection into complex feedback problems. Furthermore such a presentation allows for a clear and unambiguous description of a generating system, for example, a netview. A Signal Flow Graph (SFG) allows a fast and practical network analysis based on a clear data presentation in graphic format of the mathematical linear equations of the circuit. During creation of a SFG the Direct Current-Case (DC-Case) was observed since the correct current and voltage directions was drawn from zero frequency. In addition, the mathematical axioms, which are based on field algebra, are declared. In this work we show you in addition: How we check our SFG whether it is a consistent system or not. A signal flow graph can be verified by generating the identity of the signal flow graph itself, illustrated by the inverse signal flow graph (SFG−1). Two signal flow graphs are always generated from one circuit, so that the signal flow diagram already presented in previous sections corresponds to only half of the solution. The other half of the solution is the so-called identity, which represents the (SFG−1). If these two graphs are superposed with one another, so called 1-edges are created at the node points. In Boolean algebra, these 1-edges are given the value 1, whereas this value can be identified with a zero in the field algebra.

Numerical Simulation of Foaming Processes

The literature model studied in this article describes bubble formation and growth in a highly viscous polymer liquid with support of a gaseous matter dispersed under pressure before foaming. The foam growth is induced by the application of vacuum and mass transport of volatile components dissolved in the polymer liquid. Based on this literature model, aeration processes are calculated for intermediate viscosity and low viscosity biological systems, as they are of interest for biomatter foams, in particular for food foams in industrial processes. At the end of this article, the numerical results are presented and discussed.

Pipe Flow of Suspensions Containing Bubbles

The steady laminar pipe flow of a suspension with a gas volume fraction ∅≤0.5 and small or intermediate bubble deformations in long, and straight sections of a circular pipe is calculated. The calculations are based on the constitutive equation that was originally derived for dilute emulsions and further developed for concentrated suspensions containing bubbles. In contrast to the literature, an analytical procedure is used to determine the solution of a pipe flow more accurately. The results are presented and discussed with respect to the Reynolds number Re and capillary number Ca. If Ca 1, a bubble suspension has a parabolic velocity profile indicating a Newtonian rheology. If Ca ≈1, two regimes of flow are observed in agreement with the literature;that is, an inner plug flow where deformation rates are low and an outer flow where deformation rates are high. These results imply that, if Ca ∅?and that, if Ca ≥1, the opposite effect occurs;that is, the Reynolds number Re increases with increasing gas volume fraction.

Good Outcome after More Than a Million Troponin in Serum

A troponin in serum of more than one Million in vivo is rare insult. We report a case of 85-year-old woman who was transferred to our institution because of acute ST elevated myocardial infarction and the troponin level reached a peak of 1,032,904.2 pg/ml. She was discharged with highly reduced left ventricular function, however in the three months follow up after a coronary bypass operation she completely was free from heart failure symptoms and echocardiography showed a totally normal function of both ventricles. This case study highlights that the initial serum troponin in acute settings can mislead the long-term prognosis and gives prominence to the expeditious myocardial revascularization.

Nodal, zonal, or uniform electricity pricing： how to deal withnetwork congestion

In this paper, the main contributions to congestion management and electricity pricing, i.e., nodal, zonal, and uniform electricity pricing, are surveyed. The key electricity market concepts are structured and a formal model framework is proposed for electricity transportation, production, and consumption in the context of limited transmission networks and competitive, welfare maximizing electricity markets. In addition, the main results of existing short-run and long-run congestion management studies are explicitly summarized. In particular, the important interconnection between short-run network management approaches and optimal long-run investments in both generation facilities and network lines are highlighted.

Predicting EHL film thickness parameters by machine learning approaches

Non-dimensional similarity groups and analytically solvable proximity equations can be used to estimate integral fluid film parameters of elastohydrodynamically lubricated(EHL)contacts.In this contribution,we demonstrate that machine learning(ML)and artificial intelligence(AI)approaches(support vector machines,Gaussian process regressions,and artificial neural networks)can predict relevant film parameters more efficiently and with higher accuracy and flexibility compared to sophisticated EHL simulations and analytically solvable proximity equations,respectively.For this purpose,we use data from EHL simulations based upon the full-system finite element(FE)solution and a Latin hypercube sampling.We verify that the original input data are required to train ML approaches to achieve coefficients of determination above 0.99.It is revealed that the architecture of artificial neural networks(neurons per layer and number of hidden layers)and activation functions influence the prediction accuracy.The impact of the number of training data is exemplified,and recommendations for a minimum database size are given.We ultimately demonstrate that artificial neural networks can predict the locally-resolved film thickness values over the contact domain 25-times faster than FE-based EHL simulations(R^(2) values above 0.999).We assume that this will boost the use of ML approaches to predict EHL parameters and traction losses in multibody system dynamics simulations.

聚氨酯海绵中碳纳米管与各向异性形状Ni的协同效应增强电磁干扰屏蔽性能

巧妙的微观结构设计和合适的多组分策略仍然是高效吸收型电磁干扰屏蔽材料在轻质、低填充水平和薄样品厚度方面的挑战.本文基于独特的屏蔽胶囊结构,采用浸渍法制备了柔性水性聚氨酯/介电碳纳米管/磁各向异性镍(链或花)电磁屏蔽复合海绵.结果表明,增加镍(花状或链状)填料的含量可显著提高复合材料的导电性和电磁干扰屏蔽性能.水性聚氨酯/碳纳米管/8 wt%镍花-三聚氰胺海绵和水性聚氨酯/碳纳米管/8 wt%镍链-三聚氰胺海绵的电磁屏蔽性能分别为42.8和46.7 dB,优于仅含碳纳米管的复合海绵.碳纳米管与镍(花状或链状)之间的协同作用意味着复合海绵的屏蔽电磁干扰的主要机制来自于吸收过程.重要的是,在水性聚氨酯层的保护下,复合材料在强烈的物理和化学损伤下仍然表现出良好的电磁屏蔽性能.这项工作为设计新颖、轻量化和高效的电磁屏蔽复合材料提供了一种简单的协同策略,在便携式和可穿戴电子设备中显示出巨大的应用前景.

Conductivity of Poly(methyl methacrylate)/Polystyrene/Carbon Black and Poly(ethyl methacrylate)/Polystyrene/Carbon Black Ternary Composite Films

Poly(methyl methacrylate)(PMMA)/polystyrene(PS)/carbon black(CB)and poly(ethyl methacrylate)(PEMA)/PS/CB ternary composite films were obtained using solution casting technique to investigate double percolation effect.In both PMMA/PS/CB and PEMA/PS/CB ternary composite films,the CB particles prefer to locate into PS phase based on the results of calculating wetting coefficient,which is also confirmed by SEM images.The conductivity of the films was investigated,and the percolation threshold(￠c)of both ternary composite films with different polymer blend ratios was determined by fitting the McLachlan GEM equation.Conductivity of PMMA/PS/CB ternary composite films showed a typical double percolation effect.However,due to the double emulsion structure of PEMA/PS polymer blends,the PEMA/PS/CB ternary composite films(PEMA/PS=50/50)showed a higher￠c,even CB only located in PS phase,which conflicts with the double percolation effect.A schematic diagram combined with SEM images was proposed to explain this phenomenon.

Four-dimensional light shaping: manipulating ultrafast spatiotemporal foci in space and time

The spectral dispersion of ultrashort pulses allows the simultaneous focusing of light in both space and time,which creates socalled spatiotemporal foci.Such space–time coupling may be combined with the existing holographic techniques to give a further dimension of control when generating focal light fields.In the present study,it is shown that a phase-only hologram placed in the pupil plane of an objective and illuminated by a spatially chirped ultrashort pulse can be used to generate threedimensional arrays of spatio-temporally focused spots.By exploiting the pulse front tilt generated at focus when applying simultaneous spatial and temporal focusing(SSTF),it is possible to overlap neighboring foci in time to create a smooth intensity distribution.The resulting light field displays a high level of axial confinement,with experimental demonstrations given through two-photon microscopy and the non-linear laser fabrication of glass.

Lithological and Structural Control of Hattian Bala Rock Avalanche Triggered by the Kashmir Earthquake 2005, Sub-Himalayas, Northern Pakistan

The Kashmir earthquake 2005 （magnitude MW 7.6） triggered thousands of mass move-ments in northern Pakistan. These mass movements were mainly rock falls, debris falls, rockslides and rock avalanches. The mass movements vary in size from a few hundred cubic meters up to about 100 million cubic meters estimated for the Hattian Bala rock avalanche, the biggest one associated with this earthquake. This mass movement, which moved in southeastern direction, created two natural dams on the valley bottom and blocked the water ways of the Karli and Tung tributaries of the Jhelum River. Topographic, lithologic and structural information were used to investigate the Hattian Bala rock ava-lanche. Geotechnical and structural maps were prepared to understand relationship between geology and structure of Hattian Bala rock avalanche. The geometry and failure mode of this rock avalanche are controlled by southeast plunging synclinal structures, lithology, a bedding parallel slip surface and a pre-existing old rockslide. The structural map shows that the mass movement failure was due to Danna and Dandbeh synclinal structures plunging southeast on the hanging wall block of the reacti-vated Muzaffarabad fault. The slip surface of the mass movement followed the bedding planes along mudstone, claystone and sandstone surfaces. The mass movement perfectly followed the pre-existing synclinal morphology of the Danna and Dandbeh synclines.

Experimental and Theoretical Study on Piezoresistive Behavior of Compressible Melamine Sponge Modified by Carbon-based Fillers

High-performance compression sensors have been playing an increasingly important role in human motion detection,health monitoring and human-machine interfaces over recent years.However,it remains a great challenge to develop theoretical models providing practical guidance to the sensor design.Herein,carbon black(CB),carbon nanotubes(CNTs)and graphene nanoplatelets(GNPs)were respectively incorporated into porous melamine sponges by a facile approach of dip-coating to fabricate compression sensors.Uniaxial compression-resistance tests show that the compressibility,stability and piezoresistive sensitivity of sensors could be tailored by the filler type and concentration.A model considering the number of conductive pathways(NCP)is given to describe the relationship between the resistance change and applied compression,showing extremely good agreement with the experimental data.Also,the correlation between the equivalent filler volume fraction and conductivity is described by the other two models proposed by McLachlan and Kirkpatrick,revealing the electrical percolation thresholds(Φc)for the conductive systems under compression.Among the three fillers,CB particles endowed the composite with the best piezoresistive sensitivity but the largestΦc due to its small size and aspect ratio.A combination of experimental study and theoretical model opens up a way of further understanding the piezoresistive sensing behavior as well as optimizing the electrical property and piezoresistivity of compressive conductive polymer composite.

Molluscicidal activity of chlorophyll extraction against the freshwater snails

Objective:To evaluate the molluscicidal activity of chlorophyll extract as a photodynamic substance against the snails Lymnaea stagnalis,Biomphalaria spp.and Physa marmorata.Methods:Chlorophyllin was extracted from deep-frozen spinach.Snails were incubated in chlorophyllin containing water with 2.5,5.0,10.0 and 15.0μg/mL.All samples were kept in darkness overnight for incubation.After incubation,three samples were irradiated with simulated solar radiation for 3 h.After irradiation,the vitality of the organisms was determined.Results:The photodynamically active chlorophyllin,at low concentrations,was able to kill snails within a few hours under exposure of solar radiation.Besides,it had a killing effect by about 70%and 100%on the snails’eggs and the newly hatched snails,respectively,after 3 h exposure to solar radiation.Conclusion:The derivates of chlorophyll was a very interesting substance for photodynamic freshwater snail control.Hence,it might be a promising and cheap new strategy which probably had the potential to replace the synthetic molluscicides for snail control.

Extended sternoclavicular joint infections in cirrhotic patients: staged interdisciplinary approach with thoracic and plastic surgery

Aim: Sternoclavicular joint infection associated with liver cirrhosis is an uncommon condition and the optimal surgical treatment is undefined. Methods: Patients and methods: we retrospectively analysed data from six patients with sternoclavicular joint infections and liver cirrhosis underwent between February 2008 and May 2018 a staged therapy using negative pressure therapy followed by secondary 'en bloc' joint resection and a pectoralis muscle flap (PMF) obliteration of the thoracic wall defect. Results: Four patients successfully underwent a transfer of the PMF. The surgical revision was required for relevant bleeding in one and a tracheostomy was performed due to the prolonged intubation in another case. One patient died on the fifth day after surgery due to a cerebral septic embolic ischemia and aortic endocarditis. Conclusion: The presence of liver insufficiency and coagulopathy was associated with an extensive blood product demand and required a well-balanced interdisciplinary management. During the follow-up only a minimal restriction in the shoulder mobility was observed.