Specific Coordination Research Articles

New insights into selective flotation recovery of gold using dye-derived thermo-responsive polymeric surfactant: DFT calculation and adsorption mechanism

The selective flotation recovery of gold from secondary resources is a sustainable strategy to fill the ever-increasing demand for gold resources, and reduce the environmental pollution. In the present work, a novel method to realize the selective and fast recovery of Au(III) in the flotation process involving the use of thermo-responsive amphiphilic polymer poly(ethylene glycol)-b-poly(N-isopropylacrylamide-co-glycidyl methacrylate) (PEG113-b-P(NIPAM108-co-GMA62)) integrated with rhodamine B thiohydrazide (RBS) affinity ligand was studied. The polymer possessed the selective capture property toward Au(III) salt and excellent adsorption performance on bubble surfaces, driven by specific coordination interactions between Au(III) salt and RBS ligand, and hydrophobic interactions between GMA moieties and bubbles. Flotation using the thermo-responsive polymeric surfactant displayed a high separation efficiency and fast flotation kinetics, achieving a separation efficiency of 85% for Au(III) salt at 28 min, which was comparable with sulfur-functionalized mesoporous materials. This flotation process followed pseudo-second-order kinetics and Freundlich isotherm adsorption model. Furthermore, in flotation recovery of Au(III) salt form actual e-waste leaching solution, separation efficiency of 81% was achieved, while Au grade was improved from 1.55 % to 34.76%. This polymeric surfactant was easily regenerated by the reduction-induced release the bound Au(III) salt and thermal precipitation, leading to retain 81% of separation efficiency after five cycles. This work provides an effective way to fabricate flotation surfactant, which can meet the urgent demand for performance improvement and chemical consumption reduction in practical applications.

Control of interjoint coordination in the performance of manual circular movements can explain lateral specialization

Between-arm performance asymmetry can be seen in different arm movements requiring specific interjoint coordination to generate the desired hand trajectory. In the current investigation, we assessed between-arm asymmetry of shoulder-elbow coordination and its stability in the performance of circular movements. Participants were 16 healthy right-handed university students. The task consisted of performing cyclic circular movements with either the dominant right arm or the nondominant left arm at movement frequencies ranging from 40% of maximum to maximum frequency in steps of 15%. Kinematic analysis of shoulder and elbow motions was performed through an optoelectronic system in the three-dimensional space. Results showed that as movement frequency increased circularity of left arm movements diminished, taking an elliptical shape, becoming significantly different from the right arm at higher movement frequencies. Shoulder-elbow coordination was found to be asymmetric between the two arms across movement frequencies, with lower shoulder-elbow angle coefficients and higher relative phase for the left compared to the right arm. Results also revealed greater variability of left arm movements in all variables assessed, an outcome observed from low to high movement frequencies. From these findings, we propose that specialization of the left cerebral hemisphere for motor control resides in its higher capacity to generate appropriate and stable interjoint coordination leading to the planned hand trajectory.

Muscle synergy analysis of eight inter-limb coordination modes during human hands-knees crawling movement.

In order to reveal in-depth the neuromuscular control mechanism of human crawling, this study carries out muscle synergy extraction and analysis on human hands-knees crawling under eight specific inter-limb coordination modes, which are defined according to the swing sequence of limbs and includes two-limb swing crawling modes and six single-limb swing crawling modes. Ten healthy adults participate in crawling data collection, and surface electromyography (sEMG) signals are recorded from 30 muscles of limbs and trunk. Non-negative matrix factorization (NNMF) algorithm is adopted for muscle synergy extraction, and a three-step muscle synergy analysis scheme is implemented by using the hierarchical clustering method. Based on results of muscle synergy extraction, 4 to 7 synergies are extracted from each participant in each inter-limb coordination mode, which supports the muscle synergy hypothesis to some extent, namely, central nervous system (CNS) controls the inter-limb coordination modes during crawling movement by recruiting a certain amount of muscle synergies, rather than a single muscle. In addition, when different participants crawl in the same inter-limb coordination mode, they share more temporal features in recruiting muscle synergies. Further, by extracting and analyzing intra-mode shared synergies among participants and inter-mode shared synergies among the eight inter-limb coordination modes, the CNS is found to realize single-limb swing crawling modes by recruiting the four inter-mode shared synergy structures related to the swing function of each limb in different orders, and realize the two-limb swing crawling modes by recruiting synchronously two intra-mode shared synergy structures. The research results of the muscle synergy analysis on the eight specific inter-limb coordination modes, on the one hand, provide a basis for muscle synergy hypothesis from the perspective of crawling motion, on the other hand, also provide a possible explanation for the choice of the inter-limb coordination mode in human crawling.

PD-L1 exosomes electrochemical sensor based on coordination of AgNCs and Zr4+: Multivalent peptide enhancing target capture efficiency and antifouling performance

Programmed death ligand 1 (PD-L1) exosomes are important biomarkers of immune activation in the initial stages of treatment and can predict clinical responses to PD-1 blockade in various cancer patients. However, traditional PD-L1 exosome bioassays face challenges such as high interface fouling in complex detection environments, limited detection specificity, and poor clinical serum applicability. Inspired by the multi-branched structure of trees, a biomimetic tree-like multifunctional antifouling peptide (TMAP)-assisted electrochemical sensor was developed for high-sensitivity exosomes detection. Multivalent interaction of TMAP significantly enhances the binding affinity of PD-L1 exosomes, thanks to the designed branch antifouling sequence, TMAPs antifouling performance is further improved. The addition of Zr4+ forms coordination bonds with the exosome's lipid bilayer phosphate groups to achieve highly selective and stable binding without interference from protein activity. The specific coordination between AgNCs and Zr4+ contributes to a dramatic change in the electrochemical signals, and lowing detection limit. The designed electrochemical sensor exhibited excellent selectivity and a wide dynamic response within the PD-L1 exosome concentration range from 78 to 7.8 × 107 particles/mL. Overall, the multivalent binding ability of TMAP and the signal amplification characteristics of AgNCs have a certain driving role in achieving clinical detection of exosomes.

BHI: Embedded invisible watermark as adversarial example based on Basin-Hopping improvement

Traditional research on generating adversarial examples has mainly focused on artificially adding imperceptible perturbations to input examples. Typically, the perturbation information in adversarial examples has no practical meaning. This study proposes a novel scheme for generating adversarial examples by embedding invisible watermarks based on basin-hopping improvement (BHI). To produce adversarial examples, the proposed BHI scheme is implemented by embedding invisible watermarks into original images based on a data-hiding technique. Specifically, the BHI scheme determines the corresponding coordinates of host images and watermark sizes. By considering the specific coordinates and size, the BHI scheme invisibly embeds the watermarks into the host images to generate adversarial examples. Experimental results show that the attack success rate of the BHI scheme reaches 93.5%. The proposed BHI scheme not only completes the function of an adversarial attack but also protects the copyright of adversarial examples. Moreover, the adversarial examples exhibit outstanding visual and robust performance, providing additional visual protection to avoid the risk of attack.

Language Models for Multimessenger Astronomy

With the increasing reliance of astronomy on multi-instrument and multi-messenger observations for detecting transient phenomena, communication among astronomers has become more critical. Apart from automatic prompt follow-up observations, short reports, e.g., GCN circulars and ATels, provide essential human-written interpretations and discussions of observations. These reports lack a defined format, unlike machine-readable messages, making it challenging to associate phenomena with specific objects or coordinates in the sky. This paper examines the use of large language models (LLMs)—machine learning models with billions of trainable parameters or more that are trained on text—such as InstructGPT-3 and open-source Flan-T5-XXL for extracting information from astronomical reports. The study investigates the zero-shot and few-shot learning capabilities of LLMs and demonstrates various techniques to improve the accuracy of predictions. The study shows the importance of careful prompt engineering while working with LLMs, as demonstrated through edge case examples. The study’s findings have significant implications for the development of data-driven applications for astrophysical text analysis.

Constructed surface-enriched atomically dispersed Co–N4 active sites via stepwise pyrolysis strategy for oxygen reduction

Atomically-dispersed transition-metal nitrogen–carbon catalysts with specific coordination structures are promising cheap candidates for efficient oxygen reduction reaction (ORR) in metal–air and fuel cells. Nevertheless, a large part of internal active sites in this class of catalysts cannot really take effect, and the density of surface active sites is seriously insufficient. Here, a reasonable surface-host stepwise method involving adsorption and pyrolysis was designed to prepare Co–Nx/CNC electrocatalysts with highly-dispersed surface active sites, and to stabilize the isolated atomically dispersed Co–NX sites on the surface of graphitized N-doped carbon (NC). The new catalysts achieved admirable ORR activity with half-wave potential (E1/2) of 0.88 V under alkalinity. Moreover, Co–Nx/CNC showed stronger four-electron transfer ability and much higher stability. The main reason was that the coordination environment and density of active sites were effectively optimized, enabling the improvement of surface active sites and reactivity. This work provides a general approach to design and prepare highly-stabilized and abundant atomically-dispersed surface active sites for production in electrochemical energy devices.

STRavinsky STR database and PGTailor PGT tool demonstrate superiority of CHM13-T2T over hg38 and hg19 for STR-based applications.

Short-Tandem-Repeats (STRs) have long been studied for possible roles in biological phenomena, and are utilized in multiple applications such as forensics, evolutionary studies and pre-implantation-genetic-testing (PGT). The two reference genomes most used by clinicians and researchers are GRCh37/hg19 and GRCh38/hg38, both constructed using mainly short-read-sequencing (SRS) in which all-STR-containing-reads cannot be assembled to the reference genome. With the introduction of long-read-sequencing (LRS) methods and the generation of the CHM13 reference genome, also known as T2T, many previously unmapped STRs were finally localized within the human genome. We generated STRavinsky, a compact STR database for three reference genomes, including T2T. We proceeded to demonstrate the advantages of T2T over hg19 and hg38, identifying nearly double the number of STRs throughout all chromosomes. Through STRavinsky, providing a resolution down to a specific genomic coordinate, we demonstrated extreme propensity of TGGAA repeats in p arms of acrocentric chromosomes, substantially corroborating early molecular studies suggesting a possible role in formation of Robertsonian translocations. Moreover, we delineated unique propensity of TGGAA repeats specifically in chromosome 16q11.2 and in 9q12. Finally, we harness the superior capabilities of T2T and STRavinsky to generate PGTailor, a novel web application dramatically facilitating design of STR-based PGT tests in mere minutes.

412 Utility of a Team Science and Project Management Approach to Providing Effective Participant Recruitment Support to Research Teams: The Indiana CTSI Recruitment Concierge Service (RCS)

OBJECTIVES/GOALS: Evaluate effectiveness of participant recruitment service to improve study enrollment through customer feedback surveys and recruitment data obtained by research teams utilizing services. Use survey information to conduct gap analysis of additional support needed for participant recruitment. METHODS/STUDY POPULATION: Participant enrollment is often cited as one of the most challenging aspects of clinical research. In 2021, the Indiana CTSI used project management techniques to design and pilot a Team Science approach for providing participant recruitment support to clinical research teams. This service called the Indiana CTSI Recruitment Concierge Service (RCS) is comprised of recruitment, community engagement, social media, communications, and project management expertise. Additional experts are chosen to participate based on the study needs (regulatory, population insight, informatics, clinical services, etc.) RCS customers are comprised of study teams from a variety of areas and research experience. These customers are sent surveys to evaluate the support they received and provide suggestions for improvement. RESULTS/ANTICIPATED RESULTS: The RCS assisted 72 study teams in 2021 and 85 (as of November) in 2022. These studies were referred via word of mouth as no advertising of the service had been done to date. All customers were provided a study specific consultation with recommendations of services and resources that would assist their study. Some services recommended were: local study listing and volunteer registry (All IN for Health), digital marketing support, materials design expertise, community engagement and healthcare patient recruitment guidance. The overall feedback from RCS customers has been positive with most teams indicating the support improved their study recruitment and/or engagement plan. RCS will use information obtained to develop a strategy for prioritizing services due to the overwhelming number of requests received. DISCUSSION/SIGNIFICANCE: Using project management techniques and a Team Science approach, the Indiana CTSI was able to develop a comprehensive participant recruitment service that integrates clinical research operations, community engagement, and informatics expertise to design study specific recruitment plans and coordination of services.

Simulation of a flat solar collector with thermal storage for drying food

This research addresses the numerical simulation of a working fluid, using specialized SolidWorks Flow Simulation Software, analyzing the behavior of a drying air in a flat solar collector with thermal energy storage. In addition, one of the main centers of computational study is the relationship between flow, air temperature at the outlet of the collector and efficiency; This study allows researchers a vision of the principles of the design of these technologies, especially if it focuses on the drying of food. Then, a proposal is made on the requirements to be taken into account for the sizing of collectors based on the requirements of the product to be dried. Among the results obtained, it is established that a correctly designed collector and under a variable air flow, based on the intensity of the irradiation in specific coordinates and location, can reach efficiencies close to 30% with temperatures close to 60 ° C, being ideal for injecting this fluid into a drying chamber, where the food to be dehydrated is available. For the selection of the volume of the material for energy storage, it is recommended to take the melting temperatures as a base, with a constant flow of air, it is normal that within the system, the temperature varies depending on the position, therefore it is recommending the application of materials with different melting temperatures, which are strategically located within the storage tank.

Digital governance: A conceptual framework and research agenda

The rapid expansion of digital technologies has paved the way for new forms of organizing, facilitated by increased data and knowledge exchange between individuals and organizations. However, this poses major new challenges for designing effective governance mechanisms. This paper highlights the critical role of digital governance in facilitating digitally enabled exchange relationships. To this end, we propose a typology of analog, augmented, and automated governance modes, each associated with specific control, coordination, incentive, and trust mechanisms. Additionally, we provide a heuristic for determining the optimal governance choice via the interplay of transactivity (i.e.,the contributors, connections, and consistency in an exchange network) and corresponding governance costs. Our study advances the governance literature by defining digital governance as a distinct form and outlining key governance mechanisms and choices in the digital era. Finally, we identify avenues for future research in this field.

Upcycling of nickel iron slags to hierarchical self-assembled flower-like photocatalysts for highly efficient degradation of high-concentration tetracycline

The utilization of large-volume nickel–iron slags is largely limited by the existence of heavy metal chromium, resulting in a sharply increase environment problem. Here we report a viable strategy to fully convert nickel–iron slags into self-assembled flower-like silicate photocatalysts. Intriguingly, these decent 3D hierarchical architectures made from wild wastes are composed of core–shell structured silicates. In the meanwhile, nearly 100% chromium is extracted from the slags. Due to the high specific surface area and effective metal coordination sites (i.e., Na+, Mg2+ and Ca2+), the as-obtained silicate catalysts exhibit the extraordinary photocatalytic degradation rate (81.7 %) and the mineralization rate (27 %) of high-concentration tetracycline (100 mg/L) after 30-min Xe lamp irradiation, which are higher than those in most previous reports in terms of degradation and mineralization rates of the high-concentration tetracycline. This simple yet robust strategy to craft 3D self-assembled hierarchical flower-like silicate photocatalysts pave a novel way to the large-scale and value-added consumption of waste residues.

Virtual Musical Instruments with Python and OpenCV

There is an increasing need for musical aspirants to have access to cheaper musical instruments. This study explores the opportunities to utilize image recognition algorithms via OpenCV to port this technology into readily available modern devices, which will enable inexpensive yet authentic methods of playing a piano. Through OpenCV and Pygame libraries, one can set up a rigid camera that will trace the player’s fingers. The fingers if they cross or hover over a specific coordinate of a key, the piano note (.wav file) will be played by Pygame’s mixer module. This simple yet inexpensive option might help first-time musical aspirants experience music in an affordable and accessible way. Furthermore, this article explores the future scope of accommodating other musical instruments.

Efficacy of a Task-Oriented Intervention for Children with a Dual Diagnosis of Specific Learning Disabilities and Developmental Coordination Disorder: A Pilot Study.

Task-oriented approaches are recommended for children with developmental coordination disorder (DCD) to address deficits in motor performance and reduce activity limitations. Although this approach is used in several settings, the efficacy of these approaches in children with in dual-diagnosis of specific learning disabilities (SLD) and DCD is less widely known. This study aims to determine the effect of a group-based intervention based on neuromotor task training (NTT) principles on the motor performance of children aged 6-10 years with SLD/DCD. A pre-post-test controlled study design was conducted in children with a primary diagnosis of specific learning disabilities (SLD). DCD status was confirmed based on clinical assessment. Children scoring ≤16th percentile on the Motor Assessment Battery for Children 2nd Edition (MABC-2), who also presented with a functional motor problem, according to the MABC checklist were considered as having DCD. Children were allocated to the NTT intervention group based on teachers' perceived notion of need and received two 45-60 min training sessions per week for nine weeks. Children allocated to the usual care (UC) group, received their planned occupational therapy and physical education. The MABC-2 was used to assess changes in motor performance. Our numbers confirm that it is crucial to identify the presence of motor coordination difficulties in children who have been diagnosed with SLD. A task-oriented training program based on NTT principles, presented in small groups, has a positive effect on the motor performance in learners with neurodevelopmental disorders and this effect was larger than in the usual care group. Although using a small group format in children with multiple neurodevelopmental disorders may be challenging for the therapists, it may be a way of delivering services to children in schools for special education. Children with DCD plus LSD show improvement in their motor skills by performing group-based NTT in the school environment. Group-based NTT shows a significant improvement in the TSS score of the MABC-2 compared to usual care. Children with DCD plus SLD show equal effect sizes after NTT intervention as DCD without SLD.

Advanced two‐dimensional materials toward polysulfides regulation of metal–sulfur batteries

AbstractMetal–sulfur battery, which provides considerable high energy density at a low cost, is an appealing energy‐storage technology for future long‐range electric vehicles and large‐scale power grids. One major challenge of metal–sulfur batteries is their long‐term cycling stability, which is significantly deteriorated by the generation of various soluble polysulfide intermediates and the shuttling of these intermediates through the separator. Furthermore, the intrinsically sluggish reaction kinetics associated with the poor conductivity of sulfur/sulfides family causes a large polarization in cycle behavior, which further deteriorates the electrode rechargeability. To solve these problems, the research communities have spent a great amount of effort on designing smart cathodes to delicately tailor the physiochemical interaction between the sulfur hosts and polysulfides. Here, we summarize the key progress in the development of two‐dimensional (2D) host materials showing advantageous tunability of their physiochemical properties through coordination control methods such as defect engineering, heteroatom doping, heterostructure, and phase and interface engineering. Accordingly, we discuss the mechanisms of polysulfide anchoring and catalyzing upon specific coordination environment in conjunction with possible structure–property relationships and theoretical analysis. This review will provide prospective fundamental guidance for future sulfur host design and beyond.

Linearly structured quadratic model updating using partial incomplete eigendata

This paper presents a new method for linearly structured quadratic model updating problem for the second order damped system. This problem is concerned with updating the quadratic model with minimum adjustment preserving the linear structure of the original damped model using partially measured incomplete eigendata. It is worthwhile to note that partially measured incomplete eigendata refers to a small number of incomplete measured modal data, that is, a few natural frequencies along with some specific coordinates of the corresponding mode shapes of the model are measured. In this paper, we have proposed an optimization based approach to find the solution of the problem. Towards the end, some numerical experiments have been presented to demonstrate the efficiency and usefulness of our proposed approach.

Cuando las cruces hablan. Analisis de los rastros de ritualidad popular sobre la pared desde una optica antropologica

Since a whole series of investigations began to appear more than twenty years ago on the so-called scriptures on display up to the present day, especially those on popular epigraphs, studies on certain manifestations captured on walls have made it possible to define a very common practice, times enormously repetitive, as occurs with certain symbols of a religious nature embodied on civil and religious architecture. However, even though we have an important corpus at our disposal, there are not many interpretations of an anthropological nature that allow us to place in specific coordinates the intentions through which certain writings and symbols were shaped in very specific contexts. Through the study of three particular examples of the religious architecture of the community of Castilla y León (Spain), we try to address the intentionality of these manifestations and shed light on a phenomenon, very widespread in the Christian world, little studied to date.

Multi-Technique Experimental Benchmarking of the Local Magnetic Anisotropy of a Cobalt(II) Single-Ion Magnet.

A comprehensive understanding of the ligand field and its influence on the degeneracy and population of d-orbitals in a specific coordination environment are crucial for the rational design and enhancement of magnetic anisotropy of single-ion magnets (SIMs). Herein, we report the synthesis and comprehensive magnetic characterization of a highly anisotropic CoII SIM, [L2Co](TBA)2 (L is an N,N'-chelating oxanilido ligand), that is stable under ambient conditions. Dynamic magnetization measurements show that this SIM exhibits a large energy barrier to spin reversal U eff > 300 K and magnetic blocking up to 3.5 K, and the property is retained in a frozen solution. Low-temperature single-crystal synchrotron X-ray diffraction used to determine the experimental electron density gave access to Co d-orbital populations and a derived U eff, 261 cm-1, when the coupling between the d x 2-y 2 and dxy orbitals is taken into account, in very good agreement with ab initio calculations and superconducting quantum interference device results. Powder and single-crystal polarized neutron diffraction (PNPD, PND) have been used to quantify the magnetic anisotropy via the atomic susceptibility tensor, revealing that the easy axis of magnetization is pointing along the N-Co-N' bisectors of the N,N'-chelating ligands (3.4° offset), close to the molecular axis, in good agreement with complete active space self-consistent field/N-electron valence perturbation theory to second order ab initio calculations. This study provides benchmarking for two methods, PNPD and single-crystal PND, on the same 3d SIM, and key benchmarking for current theoretical methods to determine local magnetic anisotropy parameters.

Assembled Morphology of Copper-Thiourea Coordination-Mediated Metallo-Supramolecular Polymers.

Metallo-supramolecular polymers represent a powerful platform to construct self-assembled morphologies. Copper-thiourea (Cu-TU) coordination interactions, though have been extensively studied in small molecular system, the role of TU motifs in synthetic polymers using metal-ligand coordination to afford supramolecular aggregation and their morphology are often overlooked. Herein, an amphiphilic random copolymer, poly(oligo(ethylene glycol) ethyl acrylate-r-acylthiourea) (P(OEGEA-r-ATU)), bearing pendant TU motifs behaving as the ligand to coordinate Cu, a design characterized by core-coordinated metallo-supramolecular polymer is rationally synthesized. Indeed, rod-like nano-objects are successfully generated via the self-assembly and coordination interaction between P(OEGEA-r-ATU) and Cu.The spatial distribution of TU moieties in polymer chain, along with their Cu chelating capability, featuring the interchain coordination interaction, is tightly related to metallo-supramolecular polymer organization. The specific Cu-TU coordination interactions enable the prompted robustness and stability of soft P(OEGEA-r-ATU), induce the polymer chain configuration, which eventually furnish efficient fabrication of rod-like nano-objects via straightforward nanoprecipitation procedure. These structural motifs of copper-coordinated, rod-like nano-objects from such metallo-supramolecular polymers endow the potential therapeutic properties, such as anti-inflammatory and antitumor effects.

Indoor Localization Using Positional Tracking Feature of Stereo Camera on Quadcopter

During the maneuvering of most unmanned aerial vehicles (UAVs), the GPS is one of the sensors used for navigation. However, this kind of sensor cannot handle indoor navigation applications well. Using a camera might be the answer to performing indoor navigation using its coordinate system. In this study, we considered indoor navigation applications using the ZED2 stereo camera for the quadcopter. To use the ZED 2 camera as a navigation sensor, we first transformed its coordinates into the North, East, down (NED) system to enable the drone to understand its position and maintain stability in a particular position. The experiment was performed using a real-time application to confirm the feasibility of this approach for indoor localization. In the real-time application, we commanded the quadcopter to follow triangular and rectangular paths. The results indicated that the quadcopter was able to follow the paths and maintain its stability in specific coordinate positions.