Local Deposition Research Articles

Faradaic Rhenium Recovery with Polyvinyl Ferrocene (PVF) Electrodeposited Carbon Electrodes

Rhenium, a valuable rare element used in catalysts and superalloys, is difficult to recover in micromolar concentrations (Schulz, 2017). Electrodes coated with the redox active polymer poly vinyl ferrocene (PVF) have shown the ability to selectively adsorb several transition metal oxyanions, but limited adsorption capacity and longevity remain a challenge for these selective electrosorption technologies(Chen et al., 2021; Kim et al., 2020). In this study, we elucidate the impact of electrochemical deposition conditions on PVF coating as measured by capacitance, rhenium uptake, and longevity. PVF films were electrodeposited onto carbon substrate electrode at three different potentials across the oxidation window of the ferrocene-based metallopolymer to understand how the rate of charge transfer influences the resulting electrodeposited polymer coating. It was observed that PVF films electrodeposited at the peak oxidation current potential of 0.45 V (vs. Ag/AgCl) showed both the highest adsorption of Rhenium (458 ± 61 mg Re/g adsorbent) and capacitance (217 F/g). In comparison, the electrodeposition at 0.35 V and 0.6 V leads to a lower average capacitance 355.36 mg Re/g adsorbent and 342.03 mg Re/g adsorbent respectively. The enhanced performance for 0.45 V electro-deposited electrode can likely be attributed to a more stable deposition structure of the polymer (Pater et al., 1998), which enhances adhesion substrate and charge transfer between the substrate and the PVF. The 0.45 V electro-deposited PVF-carbon paper (PVF-CP) electrode illustrates high capacity and stability, indicating the benefits of polymer coating on selective adsorption of rhenium and prevention of electrode corrosive degradation in capacitive deionization systems. The excellent rhenium uptake and longevity demonstrates potential and will be the platform towards a full techno-economic analysis of the hybrid adsorption system in the future.Method Materials: Polyvinyl ferrocene (34801-99-5, produced by Polysciences, U.S.) and tetrabutylammonium perchlorate (1923-70-2, for electrochemical analysis, ≥99%, produced by Sigmar Aldrich Chemistry, U.S.) were used for electrodeposition. Carbon nanotubes (multiwalled, outer diameter of 7−12 nm, length of 0.5 - 10 μm, >99% carbon) were used as conductivity additives in dip coating electrode fabrication. Toray paper (carbon fiber composite carbon paper, produced by FuelCellStore) was used as the substrate for ferrocene polymer deposition under all conditions. Electrodeposition Electrodeposition performed on 2 cm x 1 cm rectangles of carbon paper substrate attached to copper wire with copper tape in a three-electrode cell configuration with a quasi-Ag/organic solution reference and CP counter electrode. 0.35 V, 0.45 V and 0.6 V were applied respectively to the working electrode in 2 mg/mL PVF solution until 0.12 C of charge had passed. Dip the electrodes into chloroform twice to rinse and stored the electrodes in the Milli-Q water. Cyclic Voltammetry (CV) CV test was performed in a three-electrode cell configuration with PVF deposited carbon paper as working electrode, platinum wire as counter electrode and Ag/AgCl reference. The voltage was swept between 0 V and 0.7 V in 0.5 M sodium perchlorate solution to capture characterize redox peak around 0.35 V. Rhenium Uptake The adsorption and desorption experiments were performed in the same three electrode cell but with a solution containing 1 mM NaReO4 or 10 mM NaCl, respectively. The voltage on working electrode maintained 0.8 V for adsorption and -0.8 V for desorption with stirring bar on the bottom stirring at 300 rpm for an hour.ResultsThe deposition happens when the positive charges transferred to the PVF that diffuse to the CP surface. The positive charged ferrocene groups combine with perchlorate, which decreases the solubility of PVF and leads to the deposition. According to the gravimetric mass measurement, the deposition mass range for 0.6 V, 0.45 V and 0.35 V are 0.1 – 0.25 mg, 0.2 – 0.35 mg and 0.4 – 0.55 mg, respectively. Comparing with theoretical deposition mass (0.26 mg, calculated from the total charge transfer), higher transition current and shorter deposition time promote a more sufficient charge transfer and a more localized deposition on the electrode interface. The CV plot (Figure 1(a)) elucidates the prominent specific capacitance for 0.45 V deposited electrode (216.50 F/g on average) and an obvious oxidize peak positive movement for 0.35 V deposition, which is corresponding to a higher deposited mass (0.4-0.55 mg) that may lead to a higher resistance. The mass normalized Re uptake reaches 457.87 mg Re/g polymer with a regeneration rate of 64.47%. For next step, the longevity test will be performed to obtain a further understanding to the depletion of regeneration rate along the increase of cycle number.

(Invited) An Overview of Electrochemistry Application to Additive Manufacturing

Additive manufacturing (AM) is the process of creating three-dimensional (3D) objects from digital models through the sequential deposition of material in layers. This talk will highlight how researchers have used electrochemical research in additive manufacturing and will provide insights into how technology can be exploited to formulate novel microstructures and optimize the manufacturing process. Electrochemical 3D printing is a relatively new form of AM that creates metallic structures through the electrochemical reduction of metal ions from solutions onto conductive substrates. It involves localized electrochemical deposition of metals combined with additive manufacturing principles to achieve Electrochemical Additive Manufacturing (ECAM). The talk will also focus on the formulation of metal precursor inks to produce novel metallic microstructures and nanoalloys containing multiple metals. These inks are used with AM techniques to fabricate 2D and 3D printed conductive structures directly onto a substrate. Examples include aligned nickel nanowires over large areas, which provide opportunities to produce structures with enhanced anisotropic electrical and magnetic properties. Nanoalloy films printed using metal precursor inks have a variety of important applications involving local control of alloy composition in AM part. Examples include the facile formation of layered nanostructures and electrical conductivity with oxidative stability. The talk will conclude with current research on electropolishing of AM parts. AM while capable of producing complex-shaped metal parts with intricate internal geometries and lattice structures struggles to make parts with the smooth surface finish required for many applications. Polishing interior surfaces inaccessible to traditional surface polishing methods is a challenge. Electropolishing is increasingly being used as a post-treatment option for metal AM parts due to its non-contact nature and ability to finish complex internal features.

Nitrogen addition affects floral and vegetative traits, reproduction, and pollinator performance in Capsicum annuum L.

It has been demonstrated that nitrogen (N) addition alters flower morphology, floral rewards and pollinator performance. However, little is known about the effects of N addition on plant reproduction, including fruit set and seed set during selfing and outcrossing, floral and vegetative traits, and pollinator performance. We hypothesized that N addition would influence fruit set, seed set in selfed and outcrossed flowers, the relationship between vegetative and flower traits, and pollinator performance. A 2-year pot experiment was conducted in which Capsicum annuum was exposed to three levels of relatively short-term N supply, i.e. 0 g m-2 (no N addition, as a control), 4 g m-2 (4N) and 16 g m-2 (16N), which are equivalent to about 0-, 1- and 4-fold of the peak local N deposition. We measured flower rewards, flower morphology, flowering phenology, as well as pollinator visitation rate, fruit set and seed set by self- and outcross-fertilization of C. annuum. The four levels of N addition increased plant biomass, biomass allocation to flowers, flower size, stigma-anther separation, nectar production and pollen production, resulting in an increase in pollinator visitation and fruit set. Nevertheless, the control and 16 levels of N addition reduced plant biomass, biomass allocation to flowers, flower size and stigma-anther separation, and nectar and pollen production, and consequently decreased pollinator visitation and fruit set. Exclusion of pollinators and hand-pollination experiments revealed that low levels of N addition were associated with high seed set in outcrossed flowers; however, this trend was reversed in flowers grown in the control and 16N treatments. Our results suggest that an optimal level of 4N can enhance the correlation between flower traits, pollinator performance and plant reproduction. Our findings cast new light on the underlying mechanisms of plant-pollinator interactions and plant adaptation to nitrogen deposition.

(Invited) Whisker Growth during Adsorbate Suppressed Electrodeposition

Anisotropic electrochemical deposition and whisker growth is shown to be a consequence of operating a bistable active-passive critical system under galvanostatic control. Specifically, whisker growth is examined during galvanostatic Cu electrodeposition from an electrolyte containing suppressor additives. Disruption of the passivating polyether-halide bilayer triggered by metal deposition leads to positive feedback and highly localized deposition. On macroscale electrodes active-passive Turing patterns develop while on micrometer-sized electrodes the bifurcation is frustrated and proceeds as a single active zone reinforced by hemispherical transport fields. Extended electrodeposition leads to symmetry breaking and lateral propagation of a single whisker. An increasing fraction of the applied current supports expansion of the passive sidewall area and eventually results in termination of anisotropic deposition. The dynamic range between passive versus active growth determines the shape and extent of whisker formation. Similar critical behavior may account for reports of whisker growth in certain metal/metal ion battery systems.

Integrated Cu–Au stereo microelectrode arrays and microfluidic channels for the electrochemical detection of glucose

Noble and transition metal nanomaterials are widely used in glucose sensing. However, the fabrication of these sensors still suffers from complex nanomaterial synthesis process and unstable nanomaterial loading on sensing surfaces. Herein, a Cu–Au bimetallic microelectrode array was prepared via local electrochemical deposition and electrochemical reduction without the need for templates and additional nanomaterial preparation processes. Based on the COMSOL computational fluid study, the obtained microelectrode arrays combined with microfluidic channels allow the continuous and rapid detection of glucose. Large number of active sites on the surface of 3D nano-arrays contributes to excellent sensing performance for glucose, with good linear detection ranges in 10 µM to 4 × 102 µM and 4 × 102 µM to 4 × 105 µM, and a low detection limit of 284 nM. The feasibility of sensor in real sample was verified by detecting glucose in beverages with good recoveries ranging from 95.50% to 104.31%.

High-efficiency localized electrochemical deposition based on ultrafast laser surface modification

Localized electrochemical deposition is a promising technology that allows for additive manufacturing of micro-nano structures in designated areas with high precision and controllability. However, ultra-low printing speed of current localized electrochemical deposition hinders its practical applications, especially the manufacturing of large-scale and complex devices. Here we propose a strategy combining ultrafast laser surface modification with traditional electrochemical deposition to achieve high-efficiency and large-scale printing. With using a focused ultrafast laser, arbitrary large-scale patterned structure can be efficiently scratched on substrate surface. Since the laser scratched region has formed nano-sized surface relief structures which experience local field enhancement when subjected to a voltage, the electrochemical deposition rate in the laser scratched region can be significantly improved, resulting in equivalent localized electrochemical deposition under traditional electrochemical deposition conditions. Such parallel electrochemical deposition can significantly shorten the printing time for large-scale devices. As for the processing of microstructure arrays with a size of 16 mm2, the printing time is compressed within 10 min, among which the electrochemical deposition process is compressed to 10 s. The results demonstrate the potential for improving the efficiency and scalability of localized electrochemical deposition through this combined approach.

Influence of morphological characteristics on the deposition of low-density lipoprotein in intracranial bifurcation aneurysms

The increasingly demonstrated association of wall enhancement (WE) measured by vascular wall imaging with the instability/rupture of intracranial aneurysms (IAs) implies the significance of investigating the transport and accumulation of blood substances [e.g., low-density lipoprotein (LDL), lipoprotein (a)] related to WE in IAs. In the present study, we perform numerical simulations to explore the relationships between the distribution/severity of LDL deposition on the lumen surface and the morphological characteristics of aneurysm and its adjacent arteries as well as the underlying fluid dynamic mechanisms. Bifurcation aneurysms located at the middle cerebral artery are selected as the subject of investigation and for which both idealized and patient-specific models are built. Studies on the idealized models reveal that the aneurysm–parent (AP) artery angle is more powerful than other morphological parameters [e.g., daughter–parent (DP) artery angle, nonsphericity index (NI) of aneurysm] in determining the severity of LDL deposition. A bleb (i.e., secondary sac) can enhance local LDL deposition, especially when located in an LDL deposition-prone aneurysm wall region. In patient-specific models, the dominant effect on the LDL deposition of the AP angle remains identifiable, whereas the effects of the DP angle and NI are overwhelmed by confounding factors. Enhanced LDL deposition prefers to appear in wall regions perpendicular to the intra-aneurysmal vortex centerline. In comparison with wall shear stress magnitude, the normal-to-tangential near-wall velocity ratio and particle residence time can better predict the localization of enhanced LDL deposition.

Measuring Anatomical Distributions of Ventilation and Aerosol Deposition with PET-CT.

In disease, lung function and structure are heterogeneous, and aerosol transport and local deposition vary significantly among parts of the lung. Understanding such heterogeneity is relevant to aerosol medicine and for quantifying mucociliary clearance from different parts of the lung. In this chapter, we describe positron emission tomography (PET) imaging methods to quantitatively assess the deposition of aerosol and ventilation distribution within the lung. The anatomical information from computed tomography (CT) combined with the PET-deposition data allows estimates of airway surface concentration and peripheral tissue dosing in bronchoconstricted asthmatic subjects. A theoretical framework is formulated to quantify the effects of heterogeneous ventilation, uneven aerosol ventilation distribution in bifurcations, and varying escape from individual airways along a path of the airway tree. The framework is applied to imaging data from bronchoconstricted asthmatics to assess the contributions of these factors to the unevenness in lobar deposition. Results from this analysis show that the heterogeneity of ventilation contributes on average to more than one-third of the variability in interlobar deposition. Actual contribution of ventilation in individual lungs was variable and dependent on the breathing rate used by the subject during aerosol inhalation; the highest contribution was in patients breathing slowly. In subjects breathing faster, contribution of ventilation was reduced, with more expanded lobes showing lower deposition per unit ventilation than less expanded ones in these subjects. The lobar change in expansion measured from two static CT scans, which is commonly used as a surrogate for ventilation, did not correlate with aerosol deposition or with PET-measured ventilation. This suggests that dynamic information is needed to provide proper estimates of ventilation for asthmatic subjects. We hope that the enhanced understanding of the causes of heterogeneity in airway and tissue dosing using the tools presented here will help to optimize therapeutic effectiveness of inhalation therapy while minimizing toxicity.

The factors that influence the electrochemical behavior of lithium metal anodes: electron transfer and Li-ion transport

Structured carbon-based hosts for the Li anode both improve the transport of Li-ions and reduce the electron transfer rate and have proven to be an effective way to suppress dendrite growth in lithium metal anodes. An in-depth understanding of these effects is needed to clarify the intrinsic electrochemical mechanism involved. We used the finite element method to simulate the two crucial processes controlling Li-ion behavior, electron transfer and Li-ion transport, and visualized the local deposition rate, the overpotential, and the Li-ion concentration in a three-dimensional (3D) Li//electrolyte//Li cell. Our analysis showed a competitive relationship between the rates of Li-ion transport and electron transfer. When the electron transfer rate is relatively slow, there are sufficient Li-ions available near the anode surface and the deposition behavior is controlled by electron transfer. However, when the number of Li-ions is low, Li-ion transport dominates the deposition process because it is unable to keep up with electron transfer, and this causes dendrite formation. Therefore, reducing the reactivity of the Li anode and accelerating Li-ion transport are the two key factors to produce uniform Li metal deposition on the anode, particularly under fast charging conditions and in practical use.

The subglottic involvement is an independent risk factor for recurrence of laryngeal amyloidosis.

To analyze the risk factors for recurrence of laryngeal amyloidosis (LA). The clinical data of patients with LA admitted in the Otolaryngology Head and Neck Surgery Department of the Second Affiliated Hospital of Xi'an Jiaotong University from August 2009 to June 2022 were analyzed retrospectively; then, the risk factors for recurrence and their impacts on the recurrence time were also analyzed. Of the 44 patients with LA, the majority (38 cases, 86.4%) only involved one anatomical region and the others (6 cases, 13.6%) involved two laryngeal regions concurrently. Overall, the glottic region was the most commonly affected area (28 cases, 63.6%), followed by the supraglottic region (16 cases, 36.4%) and subglottic region (6 cases, 13.6%). In addition, all the lesions were categorized as isolated nodule (31.8%), submucosal localized deposition (52.3%), and submucosal diffuse deposition (15.9%) according to their morphologies under electronic laryngoscope. Finally, six patients (13.6%) had recurrence after operation with a median recurrence time of 24.5months, and subglottic involvement was confirmed to be an independent risk factor for recurrence of LA by univariate and multivariate logistic regression analyses (P < 0.05). Meanwhile, the patients with subglottic involvement presented as submucosal diffuse deposition had a considerable shorter recurrence time (t = 5.759, P = 0.005). The subglottic involvement is an independent risk factor for recurrence of LA.

Equine Metabolic Syndrome: A Complex Disease Influenced by Multifactorial Genetic Factors.

Equine metabolic syndrome (EMS) has become an important issue in modern veterinary medicine and is linked to the common, extremely painful, most-of-the-time performance-terminating hoof laminitis. The growing knowledge in the field of genetic background, inducing environmental factors, diagnosis, treatment and maintenance of affected equines led us to summarise the available information to be used not only for scientific purposes but for fieldwork. In horses, the clinical presentation of EMS includes: obesity or local fat deposition, bilateral lameness or hoof rings attributed to ongoing or previous (pasted) laminitis with the key feature of the occurrence of insulin dysregulation, disturbing the homeostasis within insulin, glucose and lipid metabolism. The management of EMS is based on dietary and fitness discipline; however, intensive research is ongoing in the field of regenerative medicine to develop modern and promising therapies.

Fabrication of n-shaped micro copper structures through localized electrochemical deposition

Localized electrochemical deposition is a cost-effective technique for fabricating 3D microstructures. In this study, to fabricate a complete n-shaped micro copper structure, multi-layer deposition was adopted, and the v-groove was removed by an asymmetric trajectory. Thereafter, the merging mechanism of the n-shaped structure was analyzed using COMSOL simulations. The results demonstrated that multilayer deposition was suitable for connecting the copper column in different directions; the optimized layer was 15 layers with a height of 15 μm. The simulation showed that the v-groove was caused by the speed difference between the column and bumps, and an asymmetric trajectory with a height difference of 55 μm could suppress vertical deposition and remove the v-groove.

Ultrafast Laser‐Induced Plasmonic Modulation of Optical Properties of Dielectrics at High Resolution

AbstractThe size‐ and shape‐dependent localized surface plasmon properties of metallic nanoparticles (NPs) enable nanoscale‐enhanced near‐field applications in a wide range of fields, including spectroscopy, nonlinear optics, and sensing. Orderly assembled NPs can construct plasmonic metamaterials for light manipulation at a subwavelength scale, exhibiting new collective properties in resonant modes regulated by plasmon coupling between their fundamental components. Despite the recognition of its significant advantages in photonics integration, plasmonic‐based tailored optical responses for practical applications have remained elusive due to limitations in scaling up processes, as neither etching nor assembly can design and fabricate embedded plasmonic devices into functional devices/structures. Here, the assembly of plasmonic NPs is demonstrated by ultrafast laser‐induced writing‐on‐demand inside solids, tailoring their distribution and sizes. By controlling the laser scanning speed, the in situ redistribution of NPs is observed. Plasmon mediated local energy deposition is considered as the main mechanism driving nano‐patterning at a subwavelength range. A direct nano‐printing is realized by utilizing the resonant optical response of laser‐modified NP structures/patterns. This work paves the way for directly induced NP composite structures inside transparent materials at a well‐defined and controlled depth for plasmonic applications.

Changes in glacier albedo and the driving factors in the Western Nyainqentanglha Mountains from 2001 to 2020

AbstractGlacier surface albedo dominates glacier energy balance, thus strongly affecting the glacier mass balance. Glaciers in the Western Nyainqentanglha Mountains (WNM) experienced large mass losses in the past two decades, but long-term changes of glacier albedo and its drivers are less understood. In this study, we retrieved glacier albedo with MODIS reflectance data to characterize the spatiotemporal variability of albedo from 2001 to 2020. Air temperature, rainfall, snowfall and deposition of light-absorbing impurities (LAIs) were evaluated as potential drivers of the observed variability in glacier albedo. The results showed that: (1) the glacier albedo experienced large inter-annual fluctuations, with the mean albedo being 0.552 ± 0.002 and a clear decreasing trend of 0.0443 ± 2 × 10−4 dec−1 in the WNM. The fastest decline was observed in autumn and in the vicinity of the equilibrium line altitude, indicating an extended melt season and an expansion of the ablation region to higher elevation; (2) local meteorology and LAIs deposition are the main drivers of glacier albedo change, but their effects on seasonal albedos are different due to different glacier processes. Both air temperature and the balance between liquid and solid precipitation affect summer and autumn albedos due to glacier ablation. Air temperature is the main driver of spring and winter albedos due to sublimation and metamorphism of snow, while snowfall carried by westerlies has limited influence on these two seasonal albedos due to less snowfall. LAIs mainly affect spring albedo due to high concentration coupled with the southerly wind in spring. These findings highlight the significance of changes in glacier albedo and the key role of local meteorology and LAIs deposition in determining such changes, which play an important role in glaciological and cryosphere processes.

Alzheimer's Disease and Neurosyphilis: Meaningful Commonalities and Differences of Clinical Phenotype and Pathophysiological Biomarkers.

Neurosyphilis-associated cognitive and behavioral impairment- historically coined as "general paralysis of the insane"- share clinical and neuroradiological features with the neurodegenerative disease spectrum, in particular Alzheimer's disease (AD). Anatomopathological similarities have been extensively documented, i.e., neuronal loss, fibrillary alterations, and local amyloid-β deposition. Consequently, accurate classification and timely differential diagnosis may be challenging. To describe clinical, bio-humoral, brain MRI, FDG-PET, and amyloid-PET features in cases of neurosyphilis with an AD-like phenotypical presentation, as well as clinical outcome in terms of response to antibiotic therapy. We selected the studies comparing patients with AD and with neurosyphilis associated cognitive impairment, to investigate candidate biomarkers classifying the two neurological diseases. The neuropsychological phenotype of general paralysis, characterized by episodic memory impairment and executive disfunction, substantially mimics clinical AD features. Neuroimaging often shows diffuse or medial temporal cortical atrophy, thus contributing to a high rate of misdiagnosis. Cerebrospinal fluid (CSF)-based analysis may provide supportive diagnostic value, since increased proteins or cells are often found in neurosyphilis, while published data on pathophysiological AD candidate biomarkers are controversial. Finally, psychometric testing using cross-domain cognitive tests, may highlight a wider range of compromised functions in neurosyphilis, involving language, attention, executive function, and spatial ability, which are atypical for AD. Neurosyphilis should be considered a potential etiological differential diagnosis of cognitive impairment whenever imaging, neuropsychological or CSF features are atypical for AD, in order to promptly start antibiotic therapy and delay or halt cognitive decline and disease progression.

Global Continuous Toolpath Planning with Controllable Local Directions

Toolpath planning for Continuous fiber reinforced thermoplastic composites (CFRTPCs) 3D printing is a challenging task, which is vital to decrease the process complexity. In this paper, we propose a global continuous path planning method for CFRTPCs. First, for the set of 2D connected regions generated by slicing, we establish an optimized print sequence with a minimum idle stroke under interference constraints. Second, a continuous Zigzag path generation algorithm with controlled deposition direction is constructed for each 2D connected region, and path optimization is used to lessen the uneven deposition spacing. Finally, A separation axis theorem is used to prevent interference during the printing process, and we use a genetic algorithm to choose the connection points between 2D paths in a given spatial printing sequence to make the minimum idle stroke, creating a global continuous path with controllable deposition direction. The method proposed in this paper can provide the ability to customize the local deposition path direction and ensure the continuity of the global path to avoid interference and reduce the post-processing workload, so it is suitable for continuous path planning and multi-physics field optimization of complex structures, which can fully utilize the advantages of high-performance fibers to improve the customization ability and the performance of the fabricated parts for 3D printing and provide support for the manufacturing of high-performance structures in different fields.

The effectiveness parameters analysis for piers scour calculation

AbstractA computational fluid dynamics numerical model addressed the problem of local scouring and deposition calculation for non-cohesive sediment and clear water conditions near single and double cylindrical piers. The numerical results of single cylindrical piers correlate very well with the physical model's results while are higher than the case of the double pier, especially when the large-eddy turbulence model, the van Rijn bed-load transport equation, and fine mesh size are considered. Additionally, the final numerical predictions are compared to experimental data after parameters effectiveness explores the range of results based on projected user inputs like the bed-load equation, mesh cell size, and turbulence model.

MicroRNA397 regulates tolerance to drought and fungal infection by regulating lignin deposition in chickpea root.

Plants deposit lignin in the secondary cell wall as a common response to drought and pathogen attacks. Cell wall localised multicopper oxidase family enzymes LACCASES (LACs) catalyse the formation of monolignol radicals and facilitate lignin formation. We show an upregulation of the expression of several LAC genes and a downregulation of microRNA397 (CamiR397) in response to natural drought in chickpea roots. CamiR397 was found to target LAC4 and LAC17L out of twenty annotated LACs in chickpea. CamiR397 and its target genes are expressed in the root. Overexpression of CamiR397 reduced expression of LAC4 and LAC17L and lignin deposition in chickpea root xylem causing reduction in xylem wall thickness. Downregulation of CamiR397 activity by expressing a short tandem target mimic (STTM397) construct increased root lignin deposition in chickpea. CamiR397-overexpressing and STTM397 chickpea lines showed sensitivity and tolerance, respectively, towards natural drought. Infection with a fungal pathogen Macrophomina phaseolina, responsible for dry root rot (DRR) disease in chickpea, induced local lignin deposition and LAC gene expression. CamiR397-overexpressing and STTM397 chickpea lines showed more sensitivity and tolerance, respectively, to DRR. Our results demonstrated the regulatory role of CamiR397 in root lignification during drought and DRR in an agriculturally important crop chickpea.

Predictive value of 99mTc-MAA-based dosimetry in personalized 90Y-SIRT planning for liver malignancies

BackgroundSelective internal radiation therapy with 90Y radioembolization aims to selectively irradiate liver tumours by administering radioactive microspheres under the theragnostic assumption that the pre-therapy injection of 99mTc labelled macroaggregated albumin (99mTc-MAA) provides an estimation of the 90Y microspheres biodistribution, which is not always the case. Due to the growing interest in theragnostic dosimetry for personalized radionuclide therapy, a robust relationship between the delivered and pre-treatment radiation absorbed doses is required. In this work, we aim to investigate the predictive value of absorbed dose metrics calculated from 99mTc-MAA (simulation) compared to those obtained from 90Y post-therapy SPECT/CT.ResultsA total of 79 patients were analysed. Pre- and post-therapy 3D-voxel dosimetry was calculated on 99mTc-MAA and 90Y SPECT/CT, respectively, based on Local Deposition Method. Mean absorbed dose, tumour-to-normal ratio, and absorbed dose distribution in terms of dose-volume histogram (DVH) metrics were obtained and compared for each volume of interest (VOI). Mann–Whitney U-test and Pearson’s correlation coefficient were used to assess the correlation between both methods. The effect of the tumoral liver volume on the absorbed dose metrics was also investigated. Strong correlation was found between simulation and therapy mean absorbed doses for all VOIs, although simulation tended to overestimate tumour absorbed doses by 26%. DVH metrics showed good correlation too, but significant differences were found for several metrics, mostly on non-tumoral liver. It was observed that the tumoral liver volume does not significantly affect the differences between simulation and therapy absorbed dose metrics.ConclusionThis study supports the strong correlation between absorbed dose metrics from simulation and therapy dosimetry based on 90Y SPECT/CT, highlighting the predictive ability of 99mTc-MAA, not only in terms of mean absorbed dose but also of the dose distribution.

MAVEN Observations of the Interloop Magnetic Reconnections at Mars

Magnetic reconnection between neighboring magnetic field loops, the so-called interloop reconnection, is a common process to drive flares in the solar atmosphere. However, there is no direct evidence that a similar but less explosive process can take place on planets. The strong crustal fields on Mars generate plenty of magnetic loops in the near-Mars regions, providing a unique environment to research the interloop reconnection on a planet. Here, we report magnetic reconnection events between crustal field loops in the Martian ionosphere observed by Mars Atmosphere and Volatile EvolutioN (MAVEN) for the first time. During the current layer crossing, MAVEN recorded the characteristic signals of collisionless magnetic reconnection, including the Hall magnetic field, Alfvénic outflow, and electron energization. This finding implies that the interloop reconnection in the Martian ionosphere could contribute to the localized energy deposition and particle energization, which provides the seed source for aurora in the Martian atmosphere.