bluuebunny/crossref_metadata_2025 huggingface dataset:
Multiobjective optimal allocation problem with probabilistic non-linear cost constraint
Authors: Ghufran S , Khowaja S , Ahsan MJ
Published: March 2012

This paper considers the optimum compromise allocation in multivariate stratified sampling with non-linear objective function and probabilistic non-linear cost constraint. The probabilistic non-linear cost constraint is converted into equivalent deterministic one by using Chance Constrained programming. A numerical example is presented to illustrate the computational procedure.
Cutting power prediction model for turning of GFRP composites using response surface methodology
Authors: Hussain SA , Pandurangadu V , Kumar KP
Published: March 2012

Glass fiber reinforced plastic (GFRP) composite materials are replacing traditional engineering materials owing to their superior properties. Accordingly, the need for accurate machining of composites has increased enormously. This paper deals with the study of power consumption in machining of GFRP composite tubes of different fiber orientation angle vary from 300 to 900. Machining studies were carried out on an all geared lathe using three different cutting tools: namely Carbide (K-20), Cubic Boron Nitride (CBN) and Poly-Crystalline Diamond (PCD). Experiments were conducted based on the established Taguchi’s Design of Experiments (DOE) L25 orthogonal array on an all geared lathe. The cutting parameters considered were cutting speed, feed, depth of cut, and work piece (fiber orientation). The data collected was statistically analyzed using Analysis of variance (ANOVA) technique, and a second order mathematical model in terms of cutting parameters was developed using Response surface methodology (RSM). The results indicated that the developed model is suitable for prediction of power consumption in machining of GFRP composites. The experimental results reveals that, lower power consumption was observed at low cutting speed, low feed, moderate depth of cut and low fiber orientation angle. PCD tool performing better compared to the other tools used in this investigation.
Performance analysis of alpha divergence in nonnegative matrix factorization of monaural musical sounds
Authors: Mehta B , Verma NK , Sircar P
Published: March 2012

Estimation of original instrument sound signals from complex music signals without any prior information is one of the most challenging problems under the framework of Blind Source Separation (BSS). Due to their effectiveness in other applications of BSS, Nonnegative Matrix Factorization (NMF) based methods have particularly gained attention in the context of musical sound source separation. These techniques are based on decomposing the magnitude or power spectrum of an input signal into a sum of components with time varying gains. This is achieved by using a suitable cost function to determine the optimal factorization. Most work in this field has focused on the use of Euclidean and Kullback-Liebler (KL) divergence. This study looks into the use of α-divergence based non negative factorization in the context of single channel musical sound separation. Simulation experiments were carried on single channel mixtures of randomly mixed pitched musical instrument samples to determine optimal α values for this problem. The paper also looks into the performance of the algorithm as important system parameters are varied.
Particle swarm optimization based optimal bidding strategy in an open electricity market
Authors: Kumar JV , Kumar DMV
Published: March 2012

In an electricity market generating companies and large consumers need suitable bidding models to maximize their profits. Therefore, each supplier and large consumer will bid strategically for choosing the bidding coefficients to counter the competitors bidding strategy. In this paper, bidding strategy problem modeled as an optimization problem and solved using Particle Swarm Optimization (PSO). PSO shares many similarities with evolutionary computation techniques such as Genetic Algorithm (GA). The system is initialized with a population of random solutions and searches for optima by updating generations. However, unlike GA, PSO has no evolution operators such as crossover and mutation. In PSO, the potential solutions, called particles, fly through the problem space by following the current optimum particles. A numerical example with six suppliers and two large consumers is used to illustrate the essential features of the proposed method and the results are compared with the Genetic Algorithm (GA) approach. Test results indicate that the proposed algorithm outperforms the Genetic Algorithm approach with respect to total profit and convergence time.
Spatial linkages between coral proxies of terrestrial runoff across a large embayment in Madagascar
Authors: Grove C. A. , Zinke J. , Scheufen T. , Maina J. , Epping E. , Boer W. , Randriamanantsoa B. , Brummer G.-J. A.
Published: March 2012

Abstract. Coral cores provide vital climate reconstructions for site-specific temporal variability in river flow and sediment load. Yet, their ability to record spatial differences across multiple catchments is relatively unknown. Here, we investigate spatial linkages between four coral proxies of terrestrial runoff and their relationships between sites. Coral cores were drilled in and around Antongil Bay, the largest bay in Madagascar, and individually analysed for fifteen years of continuous luminescence (G/B), Ba/Ca, δ18Osw and δ13C data. Each coral core was drilled close to individual river mouths (≤ 7 km), and proxy data was compared to modelled river discharge and sediment runoff data for the three corresponding catchments. A reasonable agreement between terrestrial runoff proxies with modelled river discharge and sediment yield was observed. Some inconsistencies between proxy and modelled data we relate to proxy behaviour, watershed size and local environmental physiochemical parameters. In general, the further a coral resided from its river source, the weaker the proxy relationship was with modelled data and other corals, due to mixing gradients and currents. Nevertheless, we demonstrate that two coral Ba/Ca and luminescence (G/B) records influenced by the same watershed are reproducible. Furthermore, a strong Ba/Ca relationship was observed between two cores from distant watersheds, with baseline averages in agreement with modelled sediment runoff data. As humic acids behave conservatively in the water column, luminescence (G/B) data gave the highest regional correlations between cores, and most coherence with site specific modelled discharge. No statistical relationship was observed between cores in terms of interannual δ18Osw and δ13C, meaning corals were recording a localised signal at their respective sites. Comparing proxy baseline averages and mean seasonal cycles provided a good overview of the runoff dynamics of the bay system.
Simultaneous assimilation of satellite and eddy covariance data for improving terrestrial water and carbon simulations at a semi-arid woodland site in Botswana
Authors: Kato T. , Scholze M. , Knorr W. , Veenendaal E. , Kaminski T. , Kattge J. , Gobron N.
Published: March 2012

Abstract. Terrestrial productivity in semi-arid woodlands is strongly susceptible to changes in precipitation, and semi-arid woodlands constitute an important element of the global water and carbon cycles. Here, we use the Carbon Cycle Data Assimilation System (CCDAS) to investigate the mechanisms controlling ecological and hydrogical activities for a semi-arid savanna woodland site in Maun, Botswana. Twenty-four eco-hydrological process parameters of a terrestrial ecosystem model are optimized against two data streams either separately or simultaneously: daily averaged latent heat flux (LHF) derived from eddy covariance measurement, and decadal fraction of absorbed photosynthetically active radiation (FAPAR) derived from Sea-viewing Wide Field-of-view Sensor (SeaWiFS). Assimilation of both LHF and FAPAR for the years 2000 and 2001 leads to improved agreement between measured and simulated quantities not only for LHF and FAPAR, but also for photosynthetic CO2 uptake. The closest agreement is found for each observed data stream when only the same data stream is assimilated. The mean uncertainty reduction (relative to the prior) over all parameters is 16.1% for the simultaneous assimilation of LHF and FAPAR, 9.2% for assimilating LHF only, and 7.8% for assimilating FAPAR only. Furthermore, the set of parameters with the highest uncertainty reduction is similar between assimilating only FAPAR or only LHF. The highest uncertainty reduction is found for a parameter describing maximum plant-available soil moisture for all three cases. This indicates that not only LHF but also satellite-derived FAPAR data can be used to constrain and indirectly observe hydrological quantities.
Effect of Ocean acidification on growth, calcification and recruitment of calcifying and non-calcifying epibionts of brown algae
Authors: Saderne V. , Wahl M.
Published: March 2012

Abstract. Anthropogenic emissions of CO2 are leading to an acidification of the oceans by 0.4 pH units in the course of this century according to the more severe model scenarios. The excess of CO2 could notably affect the benthic communities of calcifiers and macrophytes in different aspects (photosynthesis, respiration and calcification). Seaweeds are key species of nearshore benthic ecosystems of the Baltic Sea. They frequently are the substratum of fouling epibionts like bryozoans and tubeworms. Most of those species secrete calcified structures and could therefore be impacted by the seawater pCO2. On the other hand, the biological activity of the host may substantially modulate the pH and pCO2 conditions in the thallus boundary layer where the epibionts live. The aim of the present study was to test the sensitivity of seaweed macrofouling communities to higher pCO2 concentrations. Fragments of the macroalga Fucus serratus bearing the calcifiers Spirorbis spirorbis (Annelida) and Electra pilosa (Bryozoa) and the non-calcifier Alcyonidium gelatinosum (Bryozoa) were maintained for 30 days under three pCO2 conditions: natural 460 ± 59 μatm and enriched 1193 ± 166 μatm and 3150 ± 446 μatm. Our study showed a significant reduction of growth rates and recruitment of Spirorbis individuals only at the highest pCO2. At a finer temporal resolution, the tubeworm recruits exhibited enhanced calcification of 40% during irradiation hours compared to dark hours, presumably due to the effect of photosynthetic and respiratory activities of the host alga on the carbonate system. Electra colonies showed significantly increased growth rates at 1193 μatm. No effect on Alcyonidium colonies growth rates was observed. Those results suggest a remarkable resistance of the algal macro-epibiontic communities to the most elevated pCO2 foreseen in year 2100 for open ocean (~1000 μatm) conditions possibly due to the modulation of environmental conditions by the biological activities of the host alga.
Centennial mineral dust variability in high-resolution ice core data from Dome C, Antarctica
Authors: Lambert F. , Bigler M. , Steffensen J. P. , Hutterli M. , Fischer H.
Published: March 2012

Abstract. Ice core data from Antarctica provide detailed insights into the characteristics of past climate, atmospheric circulation, as well as changes in the aerosol load of the atmosphere. We present high-resolution records of soluble calcium (Ca2+), non-sea-salt soluble calcium (nssCa2+), and particulate mineral dust aerosol from the East Antarctic Plateau at a depth resolution of 1 cm, spanning the past 800 000 years. Despite the fact that all three parameters are largely dust-derived, the ratio of nssCa2+ to particulate dust is dependent on the particulate dust concentration itself. We used principal component analysis to extract the joint climatic signal and produce a common high-resolution record of dust flux. This new record is used to identify Antarctic warming events during the past eight glacial periods. The phasing of dust flux and CO2 changes during glacial-interglacial transitions reveals that iron fertilization of the Southern Ocean during the past nine glacial terminations was not the dominant factor in the deglacial rise of CO2 concentrations. Rapid changes in dust flux during glacial terminations and Antarctic warming events point to a rapid response of the southern westerly wind belt in the region of southern South American dust sources on changing climate conditions. The clear lead of these dust changes on temperature rise suggests that an atmospheric reorganization occurred in the Southern Hemisphere before the Southern Ocean warmed significantly.
Influence of infiltration and soil storage capacity on the skewness of the annual maximum flood peaks in a theoretically derived distribution
Authors: Gioia A. , Iacobellis V. , Manfreda S. , Fiorentino M.
Published: March 2012

Abstract. Understanding the spatial variability of key parameters of flood probability distributions represents a strategy to provide insights on hydrologic similarity and building probabilistic models able to reduce the uncertainty in flood prediction in ungauged basins. In this work, we exploited the theoretically derived distribution of floods model TCIF (Two Component Iacobellis and Fiorentino model; Gioia et al., 2008), based on two different threshold mechanisms associated to ordinary and extraordinary events. The model is based on the hypotheses that ordinary floods are generally due to rainfall events exceeding a constant infiltration rate in a small source area, while the so-called outlier events responsible for the high skewness of flood distributions are triggered when severe rainfalls exceed a storage threshold over a large portion of the basin. Within this scheme, a sensitivity analysis was performed with respect to climatic and geomorphologic parameters in order to analyze the effects on the skewness coefficient and provide insights in catchment classification and process conceptualization. The analysis was conducted to investigate the influence on flood distribution of physical factors such as rainfall intensity, basin area, and particular focus on soil behavior.
Evolutionary Computation for Label Layout on Unused Space of Stacked Graphs
Authors: Toledo Alejandro , Sookhanaphibarn Kingkarn , Thawonmas Ruck , Rinaldo Frank
Published: March 2012

Placing numerous objects and their corresponding labels in the stacked graph visualization is a challenging problem. In the stacked graph, different combinations of initial parameters and filtering effects yield views with hidden information, illegible labels, and unused space. The result is a tool that does not take advantage on the unused space to reveal information to the user for further investigation. We present an automatic method for label layout on the unused space in a stacked graph. An evolutionary computation (EC) is used to optimize the best label position according to legibility requirements, as well as requirements for keeping semantic relationships between labels and their representative visual objects. A number of EC experiments, as well as a usability study on label legibility, show that our proposed solution looks promising, as compared to the traditional solutions.
Application of an Queuing Model to WiMAX-Based Wireless Mesh Networks: Grid Topology Case Study
Authors: Sattari Naeini Vahid , Movahhedinia Naser
Published: March 2012

Wireless mesh networking is an effective approach to reach high performance in the last mile of broadband Internet access. The mesh structure is the basic step toward providing cost-effective, dynamic, and high-bandwidth wireless connection. In this paper, WiMAX-like wireless mesh network is considered, emphasizing the grid arrangement which is the general topology described in the literature. To evaluate the performance of the conventional and proposed scheduling algorithms, each link is modeled using an M/D/1 queue and a virtual node concept is introduced to describe comparable performance metrics for the system. Performance measures of the system in addition to the simulation results are assessed in terms of the network length and the arrival rates.
An Investigation about the Influence of Bleaching on Shear Bond Strength of Orthodontic Brackets and on Enamel Colour
Authors: Immerz Isabell , Proff Peter , Roemer Piero , Reicheneder Claudia , Faltermeier Andreas
Published: March 2012

The aim of the study was to investigate the effect of bleaching on the colouration of tooth enamel and shear bond strength of orthodontic ceramic brackets based upon current whitening practice. The bleaching and bonding techniques were performed on extracted bovine teeth for the investigation of their colorimetric spectrum and the adhesive bond strength on surface enamel. One group was designated as the control group with no pre-treatment. Another group was treated with a 45% hydrogen peroxide solution prior to bonding. The difference in colour was expressed as the Euclidian distance ΔE. The resulting shear bond strength was analyzed and evaluated by scores of Adhesion Remnant Index. Statistical analysis was performed using the Kruskall-Wallis and post-hoc test. The colorimetric analysis revealed statistically significant differences between original and bleached as well as bleached and debonded teeth setting off a blue colour shift. Furthermore, statistically there was no significant difference noted in bonding strength between non-treated surfaces and those treated with peroxide. It can be concluded that peroxide pre-treatment does result in colour differences of teeth. Bonding and debonding procedures seem to have no statistically significant influence on the enamel colour using current materials.
Multiple Proof Approaches & Mathematical Connections
Authors: Jiang Zhonghong , O'Brien George E.
Published: March 2012

Using technology to explore the Three Altitudes of a Triangle problem, students devise many proofs for their conjectures.
Practicing Algebraic Skills: A Conceptual Approach
Authors: Friedlander Alex , Arcavi Abraham
Published: March 2012

Integrating procedures and thinking processes makes learning more meaningful.
Predictors of Disease Activity in Patients With Juvenile Idiopathic Arthritis at 12 and 24 Months After Diagnosis
Authors: Balay‐Dustrude Erin , Weiss Noel S. , Sutton Anna , Shenoi Susan
Published: June 2024

Objective

Identification of characteristics associated with active disease in juvenile idiopathic arthritis (JIA) could inform early disease treatment strategies. This study evaluated characteristics associated with active disease at 12 and 24 months after JIA diagnosis in the era in which biologic disease‐modifying antirheumatic drugs (DMARDs) became available for JIA.

Methods

This single‐center retrospective study from 2004 through 2018 assessed characteristics associated with active nonsystemic categories of JIA at 12 and 24 months after diagnosis. Relative prevalence (RP) of disease activity was evaluated in relation to prespecified characteristics. Using RP, the effect of increasing biologic DMARD availability on these predictors was assessed at 12 months.

Results

A total of 1,151 patients with JIA were included. At 12 months, a 40% to 45% higher point prevalence of active disease was noted in older children (>5 years). Patients with active disease at 3 months had a greater prevalence of active disease at 12 months (RP 1.5, 95% confidence interval [CI] 1.2–1.8) and 24 months (RP 1.3, 95% CI 1–1.6). Compared to oligoarticular JIA, polyarticular RF‐negative, psoriatic, and enthesitis‐related JIA had a greater prevalence of active disease at 12 and 24 months. At 24 months, a greater prevalence of active disease was observed in children ≥10 years. RP of active disease was 25% lower in the late cohort (2013–2018) than in the earliest cohort (2004–2008; RP 0.75, 95% CI 0.62–0.92) when more biologic medications were available, but disease activity predictors were broadly similar over time.

Conclusion

Patients with JIA with active disease at 12 and 24 months were older at diagnosis, categorized as polyarticular RF‐negative, psoriatic, or enthesitis‐related JIA. Active disease at 3 months after diagnosis was associated with worse outcomes at 12 and 24 months.
Molecular Regioisomerism of Benzobisthiazole‐Based Conjugated Polymers Promotes Photocatalytic Hydrogen Production
Authors: Hu Yongpan , Ding Xue , Feng Jie , Yan Yuchen , Shao Chaochen , Yu Xiaohan , Shao Jingfan , Ji Yujin , Li Youyong , Huang Wei , Li Yanguang
Published: June 2024

Polymer semiconductors hold great promise for photocatalytic hydrogen production due to their diverse structures and functions. Nevertheless, their photocatalytic performances are usually compromised by rapid charge recombination. Herein, a molecular regioisomerism strategy of benzobisthiazole (BT)‐based conjugated polymers is proposed for manipulating their optoelectronic properties through varying the conjugation directions of BT units. Despite subtle structural differences, the 4,8‐subsituted sample LCP‐BT‐48 exhibits an remarkably improved charge separation capability and a sixfold increase in the photocatalytic hydrogen production rate in comparison with those of the 2,6‐subsituted counterpart. Theoretical analysis demonstrates that the superior optoelectronic property of LCP‐BT‐48 is attributed to its sp2 carbon‐conjugated skeletons and enhanced local polarization electric field between BT and neighboring π‐units. This work provides a new paradigm for regulating charge‐transfer dynamics in conjugated polymers for efficient photocatalysis.
Immune Cell‐Based Microrobots for Remote Magnetic Actuation, Antitumor Activity, and Medical Imaging
Authors: Dogan Nihal Olcay , Suadiye Eylül , Wrede Paul , Lazovic Jelena , Dayan Cem Balda , Soon Ren Hao , Aghakhani Amirreza , Richter Gunther , Sitti Metin
Published: June 2024

Translating medical microrobots into clinics requires tracking, localization, and performing assigned medical tasks at target locations, which can only happen when appropriate design, actuation mechanisms, and medical imaging systems are integrated into a single microrobot. Despite this, these parameters are not fully considered when designing macrophage‐based microrobots. This study presents living macrophage‐based microrobots that combine macrophages with magnetic Janus particles coated with FePt nanofilm for magnetic steering and medical imaging and bacterial lipopolysaccharides for stimulating macrophages in a tumor‐killing state. The macrophage‐based microrobots combine wireless magnetic actuation, tracking with medical imaging techniques, and antitumor abilities. These microrobots are imaged under magnetic resonance imaging and optoacoustic imaging in soft‐tissue‐mimicking phantoms and ex vivo conditions. Magnetic actuation and real‐time imaging of microrobots are demonstrated under static and physiologically relevant flow conditions using optoacoustic imaging. Further, macrophage‐based microrobots are magnetically steered toward urinary bladder tumor spheroids and imaged with a handheld optoacoustic device, where the microrobots significantly reduce the viability of tumor spheroids. The proposed approach demonstrates the proof‐of‐concept feasibility of integrating macrophage‐based microrobots into clinic imaging modalities for cancer targeting and intervention, and can also be implemented for various other medical applications.
On‐Chip THz Helical Antenna Based on Metal Self‐Rolled‐up Membrane Nanotechnology
Authors: Li Longyu , He Wei , Zhou Zhikun , Yuan Tao , Sang Lei , Mei Yongfeng , Chen Xiaochen , Huang Wen
Published: June 2024

This paper demonstrates the on‐chip terahertz (THz) helical antenna based on metal self‐rolled‐up membrane (M‐SRuM) nanotechnology, which utilizes the residual stress in multilayer metal membrane deposited by electron beam (E‐beam) evaporation to provide the rolling force and to form the radiation body of the helical antenna. Precise design method is proposed based on multi‐physics modeling for mechanical and electrical analysis, and the two operating modes of on‐chip helical antenna are modeled and analyzed. The test results show that the normal mode of self‐rolled‐up THz helical antenna is able to operate at frequency as high as 0.223 THz with the corresponding impedance bandwidth of 13 GHz.
On the Effect of Donor Strength on the Photoluminescence Performance in Mono‐Substituted N‐Donor Triarylmethyl Radicals
Authors: Arnold Mona E. , Roß Lars , Thielert Philipp , Bartley Francisca , Zolg Julia , Bartsch Florian , Kibler Ludwig A. , Richert Sabine , Bannwarth Christoph , Kuehne Alexander J. C.
Published: June 2024

The functionalization of light‐emitting triarylmethyl radicals with electron‐donating moieties can significantly increase their photoluminescence quantum yield ϕ. As luminophores in light‐emitting diodes, such open‐shell radicals can be used to overcome the problem of spin‐statistics inherent to conventional closed‐shell emitters. However, so far the functionalization of triarylmethyl radicals with donors of varying strength is limited by the restricted reactivity of the triarylmethyl radical, constraining optimization of performance to empirical trial and error approaches. Here, the reliable reactivity of N‐heterocyclic donors is used in radical‐mediated aromatic substitutions, allowing to systematically investigate the effect of donor strength on the emission characteristics of triarylmethyl radicals. As a single descriptor proxy to the donor strength, the ionization energy IE of the donor moiety is employed, which is determined by density functional theory calculations. A systematic bathochromic shift of the emission wavelength λmax is observed for increasing donor strength, while maximum ϕ values are obtained for medium‐strength donors. These effects are rationalized with a simple model based on Marcus theory supported by quantum chemical calculations and electron paramagnetic resonance. This allows to understand the effect of the donor strength on both λmax and ϕ, enabling the design of improved light‐emitting radicals in the future.
Analysis of Optical Temperature Sensing Performance of Alkali Metal Doped Na0.5Gd0.5TiO3: Yb, Er Based on Judd‐Ofelt Theory and First Principles Calculations
Authors: Yuan Li , Wang Xu , Tang Yanlin , Cui Ruirui , Deng Chaoyong
Published: June 2024

In alkali metal‐doped optical temperature measurement materials, the influence of the electronegativity difference of alkali metal ions on optical temperature measurement performance is rarely reported. This study investigates and analyzes the performance of optical temperature measurement of Na0.5Gd0.5TiO3: Yb, Er doped with Li+ and K+ ions, utilizing the Judd‐Ofelt theory and the first‐principles method. The results reveal that the sensitivities increase with the increase of atomic number of doped alkali metal ions. The reason is that a difference in ionic radius between the dopant and the replaced ion decreases the symmetry of the crystal field and increases the value of Ω2. The doping K+ with low electronegativity leads to an increase in the s orbital electron density of rare earth ions, thereby repelling the d orbital electrons, reducing the d electron density, and decreasing the value of Ω6. Based on the Judd‐Ofelt theory, a combination of a large Ω2 and a small Ω6 is expected to enhance the absolute sensitivity of optical temperature‐measuring materials doped with rare earth ions. Therefore, it can be concluded that doping an ion with low electronegativity and a significant radius difference from the substitution site is beneficial for enhancing the optical temperature sensitivity.
Tight Junction Component Occludin Binds to FIP5 to Regulate Endosome Trafficking and Mitotic Spindle Function
Authors: Zhang Zichao , Chen Jing , Ma Rongze , Xu Chongshen , Lu Yunzhe , Zhou Jiecan , Xia Kun , Lu Pengfei
Published: June 2024

The genetic basis of vertebrate emergence during metazoan evolution has remained largely unknown. Understanding vertebrate‐specific genes, such as the tight junction protein Occludin (Ocln), may help answer this question. Here, it is shown that mammary glands lacking Ocln exhibit retarded epithelial branching, owing to reduced cell proliferation and surface expansion. Interestingly, Ocln regulates mitotic spindle orientation and function, and its loss leads to a range of defects, including prolonged prophase and failed nuclear and/or cytoplasmic division. Mechanistically, Ocln binds to the RabGTPase‐11 adaptor FIP5 and recruits recycling endosomes to the centrosome to participate in spindle assembly and function. FIP5 loss recapitulates Ocln null, leading to prolonged prophase, reduced cell proliferation, and retarded epithelial branching. These results identify a novel role in OCLN‐mediated endosomal trafficking and potentially highlight its involvement in mediating membranous vesicle trafficking and function, which is evolutionarily conserved and essential.
Single‐Cell Chromatin Accessibility Analysis Reveals Subgroup‐Specific TF‐NTR Regulatory Circuits in Medulloblastoma
Authors: Gao Xiaoyue , Zhuang Qiyuan , Li Yun , Li Guochao , Huang Zheng , Chen Shenzhi , Sun Shaoxing , Yang Hui , Jiang Lan , Mao Ying
Published: June 2024

Medulloblastoma (MB) stands as one of the prevalent malignant brain tumors among pediatric patients. Despite its prevalence, the intricate interplay between the regulatory program driving malignancy in MB cells and their interactions with the microenvironment remains insufficiently understood. Leveraging the capabilities of single‐cell Assay for Transposase‐Accessible Chromatin sequencing (scATAC‐seq), the chromatin accessibility landscape is unveiled across 59,015 distinct MB cells. This expansive dataset encompasses cells belonging to discrete molecular subgroups, namely SHH, WNT, Group3, and Group4. Within these chromatin accessibility profiles, specific regulatory elements tied to individual subgroups are uncovered, shedding light on the distinct activities of transcription factors (TFs) that likely orchestrate the tumorigenesis process. Moreover, it is found that certain neurotransmitter receptors (NTRs) are subgroup‐specific and can predict MB subgroup classification when combined with their associated transcription factors. Notably, targeting essential NTRs within tumors influences both the in vitro sphere‐forming capability and the in vivo tumorigenic capacity of MB cells. These findings collectively provide fresh insights into comprehending the regulatory networks and cellular dynamics within MBs. Furthermore, the significance of the TF‐NTR regulatory circuits is underscored as prospective biomarkers and viable therapeutic targets.
Frequency‐Selective, Multi‐Channel, Self‐Powered Artificial Basilar Membrane Sensor with a Spiral Shape and 24 Critical Bands Inspired by the Human Cochlea
Authors: Jeon Eun‐Seok , Lee Useung , Yoon Seongho , Hur Shin , Choi Hongsoo , Han Chang‐Soo
Published: June 2024

A spiral‐artificial basilar membrane (S‐ABM) sensor is reported that mimics the basilar membrane (BM) of the human cochlea and can detect sound by separating it into 24 sensing channels based on the frequency band. For this, an analytical function is proposed to design the width of the BM so that the frequency bands are linearly located along the length of the BM. To fabricate the S‐ABM sensor, a spiral‐shaped polyimide film is used as a vibrating membrane, with maximum displacement at locations corresponding to specific frequency bands of sound, and attach piezoelectric sensor modules made of poly(vinylidene fluoride‐trifluoroethylene) film on top of the polyimide film to measure the vibration amplitude at each channel location. As the result, the S‐ABM sensor implements a characteristic frequency band of 96‐12,821 Hz and 24‐independent critical bands. Using real‐time signals from discriminate channels, it is demonstrated that the sensor can rapidly identify the operational noises from equipment processes as well as vehicle sounds from environmental noises on the road. The sensor can be used in a variety of applications, including speech recognition, dangerous situation recognition, hearing aids, and cochlear implants, and more.
Immunoprotection Strategies in β‐Cell Replacement Therapy: A Closer Look at Porcine Islet Xenotransplantation
Authors: Grimus Sarah , Sarangova Victoria , Welzel Petra B. , Ludwig Barbara , Seissler Jochen , Kemter Elisabeth , Wolf Eckhard , Ali Asghar
Published: June 2024

Type 1 diabetes mellitus (T1DM) is characterized by absolute insulin deficiency primarily due to autoimmune destruction of pancreatic β‐cells. The prevailing treatment for T1DM involves daily subcutaneous insulin injections, but a substantial proportion of patients face challenges such as severe hypoglycemic episodes and poorly controlled hyperglycemia. For T1DM patients, a more effective therapeutic option involves the replacement of β‐cells through allogeneic transplantation of either the entire pancreas or isolated pancreatic islets. Unfortunately, the scarcity of transplantable human organs has led to a growing list of patients waiting for an islet transplant. One potential alternative is xenotransplantation of porcine pancreatic islets. However, due to inter‐species molecular incompatibilities, porcine tissues trigger a robust immune response in humans, leading to xenograft rejection. Several promising strategies aim to overcome this challenge and enhance the long‐term survival and functionality of xenogeneic islet grafts. These strategies include the use of islets derived from genetically modified pigs, immunoisolation of islets by encapsulation in biocompatible materials, and the creation of an immunomodulatory microenvironment by co‐transplanting islets with accessory cells or utilizing immunomodulatory biomaterials. This review concentrates on delineating the primary obstacles in islet xenotransplantation and elucidates the fundamental principles and recent breakthroughs aimed at addressing these challenges.
Versatile Design of NO‐Generating Proteolipid Nanovesicles for Alleviating Vascular Injury
Authors: Yang Yueyue , Zhang Xiangyun , Yan Hongyu , Zhao Rongping , Zhang Ruixin , Zhu Liuyang , Zhang Jingai , Midgley Adam C. , Wan Ye , Wang Songdi , Qian Meng , Zhao Qiang , Ai Ding , Wang Ting , Kong Deling , Huang Xinglu , Wang Kai
Published: June 2024

Vascular injury is central to the pathogenesis and progression of cardiovascular diseases, however, fostering alternative strategies to alleviate vascular injury remains a persisting challenge. Given the central role of cell‐derived nitric oxide (NO) in modulating the endogenous repair of vascular injury, NO‐generating proteolipid nanovesicles (PLV‐NO) are designed that recapitulate the cell‐mimicking functions for vascular repair and replacement. Specifically, the proteolipid nanovesicles (PLV) are versatilely fabricated using membrane proteins derived from different types of cells, followed by the incorporation of NO‐generating nanozymes capable of catalyzing endogenous donors to produce NO. Taking two vascular injury models, two types of PLV‐NO are tailored to meet the individual requirements of targeted diseases using platelet membrane proteins and endothelial membrane proteins, respectively. The platelet‐based PLV‐NO (pPLV‐NO) demonstrates its efficacy in targeted repair of a vascular endothelium injury model through systemic delivery. On the other hand, the endothelial cell (EC)‐based PLV‐NO (ePLV‐NO) exhibits suppression of thrombosis when modified onto a locally transplanted small‐diameter vascular graft (SDVG). The versatile design of PLV‐NO may enable a promising therapeutic option for various vascular injury‐evoked cardiovascular diseases.
The 3D Monolithically Integrated Hardware Based Neural System with Enhanced Memory Window of the Volatile and Non‐Volatile Devices
Authors: Jeon Yu‐Rim , Seo Donguk , Lee Yoonmyung , Akinwande Deji , Choi Changhwan
Published: June 2024

3D neuromorphic hardware system is first demonstrated in neuromorphic application as on‐chip level by integrating array devices with CMOS circuits after wafer bonding (WB) and interconnection process. The memory window of synaptic device is degraded after WB and 3 Dimesional (3D) integration due to process defects and thermal stress. To address this degradation, Ag diffusion in materials of Ta2O5and HfO2is studied in a volatile memristor, furthermore, the interconnection and gate metal Ru are investigated to reduce defective traps of gate interface in non‐volatile memory devices. As a result, a memory window is improved over 106in both types of devices. Improved and 3D integrated 12 × 14 array devices are identified in the synaptic characteristics according to the change of the synaptic weight from the interconnected Test Element Group (TEG) of the Complementary Metal Oxide Semiconductor (CMOS) circuits. The trained array devices present recognizable image of letters, achieving an accuracy rate of 92% when utilizing a convolutional neural network, comparing the normalized accuracy of 93% achieved by an ideal synapse device. This study proposes to modulate the memory windows up to 106in an integrated hardware‐based neural system, considering the possibility of device degradation in both volatile and non‐volatile memory devices demonstrated by the hardware neural system.
Polarization Anisotropy of Ultrafast Electronic Dynamics in AB‐Stacked Rhenium Disulfide
Authors: Qin Yulu , Wang Rui , Zhang Jianing , Zhang Yeqinbo , Wang Yunkun , Li Xiaofang , Gao Yunan , Peng Liang‐You , Gong Qihuang , Liu Yunquan
Published: June 2024

Revealing transient electronic properties in anisotropic 2D materials is a prerequisite for developing ultrafast optoelectronic functional devices. Here, the ultrafast electronic dynamics of polarization anisotropy for the AB‐stacked rhenium disulfide (ReS2) are studied using time‐ and energy‐resolved photoemission electron microscopy. The ultrafast electronic relaxation process exhibits sensitive layer‐dependent polarization anisotropy. The linear dichroism of the ultrafast electronic dynamics is also measured, indicating that the polarization anisotropy is determined by the fast process on the sub‐picosecond scale. With ab initio theory calculations, it is confirmed that the ultra‐sensitive layer dependence of the lifetime of the fast process originates from a stronger interlayer coupling in the K‐Γ direction (along the b‐axis) of ReS2. Further, by analyzing the time‐resolved photoemission energy spectrum, distinct “fast” and “slow” regimes are found in the ultrafast dynamics of excited electrons with different energies. The corresponding energy windows also show substantial polarization anisotropy, which is associated with the linear dichroism of the electron‐phonon coupling in the AB‐stacked ReS2. This work has implications for the design of angle‐sensitive optoelectronic functional devices with the AB‐stacked ReS2.
2D Fractal Arrays of Ultrathin Silicon Nanowires as Cost‐Effective and High‐Performance Substrate for Supercapacitors
Authors: Leonardi Antonio Alessio , Arrigo Antonino , Lo Faro Maria José , Nastasi Francesco , Irrera Alessia
Published: June 2024

Silicon is the most diffused material in the industry; thus, considering its high capacity for energy storage, silicon‐based materials are well studied as battery anodes and supercapacitors. Si nanowires (NWs) emerge due to the high surface to volume ratio, its compatibility with a wafer processing typical of microelectronics, and are studied as anodes for lithium batteries as well as coupled with other materials for supercapacitor application. In this article, the synthesis and application are reported as a lithium anode of 2D fractal arrays of ultrathin Si NWs obtained by a thin‐film metal‐assisted chemical etching (MACE). These Si NWs exhibit a density of about 1012 NWs cm−2, maximizing the surface to volume ratio compared to silver‐salts MACE and other NW fabrication approaches. By using 2.7 μm long NWs, a pseudo‐capacitor behavior with a specific capacitance of about 274.2 μF cm−2at a scan rate of 50 mV s−1is obtained. This specific capacitance is two orders of magnitude higher than the one obtained in the same condition by using NWs synthesized by silver‐salt MACE. In this result, the route is opened toward the application of these fractal arrays of ultrathin Si NWs as substrate for supercapacitors with improved efficiency.
Discovery of mineralization in the caudal vertebrae of perch (Perca fluviatilis L.): A potential new tool for environmental impact assessment
Authors: Karlsson O. Magnus , Delling Bo , Viktor Tomas , Sandström Olof , Waldetoft Hannes , Bengtsson Bengt‐Erik
Published: June 2024

The frequency of skeletal deformations in fish is a common biomarker when investigating the environmental response to effluents of various origins. This study discovered a new biomarker: elevated mineralization levels of the vertebrae in the caudal region of perch Perca fluviatilis. The study was conducted in northern Sweden in lakes receiving discharges from an iron ore mine and adjacent reference lakes. The field observation was followed up with an egg‐hatching experiment showing a similar lake‐specific pattern in hatching and deformation frequencies in larvae.
Winter cover crop performance in the Southern Piedmont region of South Carolina
Authors: Davis Payton B. , Park Dara M. , Poncet Aurelie M. , Russell Brook T. , Sahoo Debabrata
Published: June 2024

Cover crops (CCs) offer in‐field and environmental benefits when integrated into cropping systems. Low CC adoption in the Southern Piedmont region of South Carolina is partially due to the lack of information on CC performance and benefits within the region. To address this, eight winter CCs and a fallow/pigweed (Amaranthus spp.) treatment were investigated for their influence on soil temperature, volumetric water content (VWC), percent cover, biomass, and the occurrence of soil water repellency (SWR). A randomized complete block design experiment was conducted in the fall and winter of 2021–2022 (EXP A) and repeated in 2022–2023 (EXP B). Experiments were treated separately as methods were revised for EXP B. CCs minimally influenced soil VWC over both experiments with no consistent trend. CC did not influence soil temperatures during EXP A. In EXP B, the fallow/pigweed had the highest soil temperatures on two (out of 10) measuring events (p < 0.05). No SWR was found in either experiment. Establishment and fresh and dry CC biomass were most likely influenced by air temperatures and daylight hours driving germination during days with minimal rainfall. In both experiments, annual rye (Lolium multiflorum) produced cover quickly and yielded high biomass. Crimson clover (Trifolium incarnatum) took longer to establish but also yielded one of the highest biomasses. This study demonstrated that winter CCs had little influence on soil physical properties and that while cereal rye (Secale cereale) is a common CC utilized for erosion control, the greater biomass and surface roots of annual rye make it a superior CC for use in Southern Piedmont agroecosystems.
The impact of alternative arrangements, contingent jobs, and work secured through an app on the well‐being of working age adults: Results from the California Work and Health Survey
Authors: Yelin Edward , Trupin Laura , Iley Trisha , Rhee Nari , Lafrance Alicia , Varghese Mac Ima
Published: June 2024

Background

There is recognition of the growing prevalence of alternative work arrangements, contingent jobs, and work secured through an app. However, there have been few systematic efforts to understand the impact of these forms of work on individuals and households.

Methods

The data derive from the California Work and Health Survey administered to a sample of the working age population of the state solicited through random‐digit dialing of cell phone numbers. 4014 individuals completed the survey, 26% of those with an in‐service cell phone number. We present odds ratios and 95% confidence intervals from logistic regression estimating the impact of being an independent contractor, in other forms of alternative work arrangements, in contingent jobs, and in work secured through an app, on economic and health status and working conditions in main jobs, with and without adjustment for covariates.

Results

Several of the forms of work analyzed are associated with lower earnings and higher rates of wage theft, household poverty, benefit recipiency, and expectation of hardships in food, housing, and medical care in the immediate future. Association between the forms of work and current health status is less consistent. However, several forms of work are associated with working conditions known to be risk factors for subsequent health problems.

Conclusions

Public policy to mitigate the adverse impacts of work, largely developed in the 20th Century when there was an identified workplace, may be insufficient to protect workers' well‐being for alternative work arrangements, contingent jobs, and work secured through an app.
Effectiveness of smoking cessation interventions in the workplace: A systematic review and meta‐analysis
Authors: Ayaz Dilek , Asi Ercan , Meydanlioglu Ayse , Oncel Selma
Published: June 2024

Objectives

Workplaces are suitable areas for smoking cessation programs and incentives. This study was carried out to determine the effectiveness of interventions in the workplace for smoking cessation in working individuals.

Methods

All studies published in English between 2013 and 2022 were searched in Pub Med, Science Direct, Scopus, Web of Science, and CINAHL databases. Meta‐analysis was based on PRISMA 2020. The study protocol was registered with PROSPERO. A random effects model was applied to the meta‐analysis processes, and Hedges' g was used to calculate the effect size.

Results

Of the included studies, 11 were randomized controlled trials, and 8 were cluster randomized controlled trials. In different working sectors, various interventions such as motivational/individual interviews, group counseling, telephone coaching, web‐based training, mindfulness meditation, and financial interventions were implemented. These interventions were carried out alone or in combination with one or more other interventions. The interventions generally have short‐term effects, and financial incentives or supports were the factors that positively motivate the interventions. The joint effect size of attempts to quit smoking in the workplace (Hedges' g) was 1.171. Heterogeneity between studies was significant (Q = 199.762, p = 0.015, I2 = 80.477%). No publication bias was detected.

Conclusions

We determined that smoking cessation interventions applied in the workplace have a large effect. We recommend that the long‐term effects of increasing effectiveness of these interventions be considered and planned in line with the needs of working groups.