Effect of the Surface Charge-Dependent Boundary Slip on the Electrophoresis of a Hydrophobic Polarizable Rigid Colloid.

The electrophoresis of a hydrophobic charged rigid colloid is studied by considering the lateral movement of the adsorbed surface charge. The slip velocity condition at the hydrophobic surface is modified to take into account the impact of the frictional and electric forces created by the adsorbed laterally mobile surface charge. Though the dependency of the surface charge on the slip velocity in the context of electrophoresis has been addressed before, the effect of the laterally mobile adsorbed surface charge on the electrophoresis of hydrophobic colloids has not been studied. The dielectric colloid is considered to polarize and create an induced immobile surface charge when subjected to an imposed electric field. The impact of the mobile surface charge along with the immobile induced surface charge on electrophoresis of a hydrophobic colloid is elucidated by numerically solving the governing electrokinetic equations in their full form. We have also developed a simplified model under a weak applied field consideration, which can be further reduced to a closed-form analytic expression for the mobility under the Debye-Hückel approximation. This analytic model for mobility is in excellent agreement with the exact numerical solution for an entire range of the Debye length when the ζ-potential is in the order of the thermal potential. One of the notable features of this closed-form mobility expression is that it accounts for the mobile adsorbed surface charge on the hydrodynamic slip condition and the dielectric polarization of the particle. We find that the mobility of the surface charge decreases the electrophoretic mobility of the hydrophobic dielectric colloid. However, the mobile surface charge enhances the mobility of a conducting hydrophobic colloid.

Isolation and characterization of rhizobacteria from lentil for arsenic resistance and plant growth promotion.

Low-cost microbial remediation strategies serve as a viable and potent weapon for curbing the arsenic menace. In the present study, two arsenic-resistant bacteria were isolated from the contaminated lentil rhizosphere in Gangetic plain of eastern India. LAR-21 (Burkholderia cepacia, MW356875) and LAR-25 (Burkholderia cenocepacia, MW356894) could remove 87.6% and 85.9% of arsenite (10 mM) from the liquid culture medium in laboratory condition. They were highly resistant to arsenate and arsenite and also had a high arsenite oxidase activity. LAR-21 showed the highest level of minimum inhibitory concentration value of 390 mM for arsenate and 31 mM for arsenite. The same strain was found to show highest arsenite oxidase activity, i.e., 5.2 nM min-1 mg-1of protein. These two strains further possess potential plant growth-promoting characteristics like indole acetic acid production (5-15 mM IAA mL-1), 1-aminocyclopropane-1-carboxylate deaminase (8-21 nM α-keto butyrate mg protein-1 h-1), nitrogenase activity (3-8.99 nM ethylene mg cell protein-1 h-1), siderophore production (17-22.1 µM deferoxamine mesylate mL-1), phosphate solubilization (261-453 µg mL-1) under arsenic stress condition. The plant growth promotion of the strains was further validated by pot study of lentil by assessing their agronomic and growth-related traits, and potential to recover from arsenic stress (17.2-21.2% arsenic reduction in root and shoot, 16-19.2% in leaf and pod, and 15-23% reduction in seeds). The LAR-21 strain, thus, emerged as the most suited candidate for bioremediation and plant (lentil) growth promotion in arsenic polluted environment.

Observation of High Magnetic Bistability in Lanthanide (Ln = Gd, Tb and Dy)-Grafted Carbon Nanotube Hybrid Molecular System.

There is an immense research interest in molecular hybrid materials posing novel magnetic properties for usage in spintronic devices and quantum technological applications. Although grafting magnetic molecules onto carbon nanotubes (CNTs) is nontrivial, there is a need to explore their single molecule magnetic (SMM) properties post-grafting to a greater degree. Here, we report a one-step chemical approach for lanthanide-EDTA (Ln = GdIII, 1; TbIII, 2 and DyIII, 3) chelate synthesis and their effective grafting onto MWCNT surfaces with high magnetic bistability retention. The magnetic anisotropy of an Ln-CNT hybrid molecular system by replacing the central ions in the hybrid complex was studied and it was found that system 1 exhibited a magnetization reversal from positive to negative values at 70 K with quasi-anti-ferromagnetic ordering, 2 showed diamagnetism to quasi-ferromagnetism and 3 displayed anti-ferromagnetic ordering as the temperature was lowered at an applied field of 200 Oe. A further analysis of magnetization (M) vs. field (H) revealed 1 displaying superparamagnetic behavior, and 2 and 3 displaying smooth hysteresis loops with zero-field slow magnetic relaxation. The present work highlights the importance of the selection of lanthanide ions in designing SMM-CNT hybrid molecular systems with multi-functionalities for building spin valves, molecular transistors, switches, etc.

Diffusiophoresis of a Charged Droplet in Asymmetric as Well as Mixed Electrolytes through Numerical and Semianalytic Models.

A numerical study on the diffusiophoresis of a droplet in an electrolyte medium is carried out by solving the full set of coupled governing equations, which are based on the conservation principle. Diffusiophoresis is considered for monovalent as well as non-z:z electrolytes and mixed electrolytes. The numerical model is supplemented with a semianalytic simplified model based on first-order perturbation analysis, which agrees with the numerical model for a low to moderate range of surface potential. The mobility for a low-viscosity fluid at a thinner Debye length is dominated by the chemiphoresis part, which creates the mobility to become an even function of the surface charge density for a monovalent electrolyte. Such a pattern in mobility does not appear in a non-z:z asymmetric electrolyte. At a thinner Debye length, diffusiophoresis becomes independent of the diffusion field, hence the mobility is independent of the composition of electrolytes in a mixed monovalent electrolyte solution. Our results show that the size-based sorting of droplets is efficient when a mixed electrolyte is considered. We have also addressed the finite ion size effects by considering a modified ion transport equation. One of the key features of the present study is the simplified semianalytical model for the diffusiophoresis of a droplet in a z:z electrolyte as well as in non-z:z and mixed electrolytes, which is shown to be valid up to a moderate range of surface potential for a finite Debye length.

Colchicine-mediated in vitro polyploidization in gerbera hybrid.

An efficient in vitro protocol for high-frequency polyploidization for the first time in gerbera hybrid (BGC-2019-01) was developed in the present study. Two-week-old in vitro-developed shoots (tips) were treated individually with 0.1%, 0.25% and 0.5% (w/v) colchicine solutions for 4, 6, 8, and 12 h. The colchicine-treated shoot tips were then inoculated on Murashige and Skoog (MS) medium fortified with 1.5 mg/l meta-Topolin for multiple shoot proliferation and later transferred into 1.5 mg/l indole-3-acetic acid-fortified MS medium for rooting of shoots. The ploidy levels of the colchicine-treated and regenerated plantlets along with the non-treated ones were confirmed via flow cytometry analysis and metaphasic chromosome count. The highest frequency of tetraploid plantlets (50%) were obtained when shoot tips were treated with 0.1% colchicine for 4 h. Morphological observations revealed that induced tetraploid plantlets exhibited delayed fresh shoot initiation, fewer but longer shoots, as well as fewer but broader leaves. Likewise, the study of stomata revealed that in comparison to their diploid counterparts, the tetraploid plantlets exhibited less frequent yet significantly larger stomata, and higher number of chloroplasts. The tetraploids were recorded with significantly higher chlorophyll, carotenoid, and anthocyanin content during the photosynthetic pigment analyses. During ex vitro acclimatization and field growth, the tetraploid plants exhibited delayed proliferation but with higher vigor and thickened broad leaves. The genetic uniformity among the diploid and the tetraploid plants was confirmed using conserved DNA-derived polymorphism (CDDP), directed amplification of minisatellite-region DNA (DAMD), inter simple sequence repeats (ISSR), and start codon targeted (SCoT) polymorphism marker systems. The tetraploids developed in the present study would be of immense importance for the genetic improvement of gerbera as far as its ornamental values are concerned.

A mis-splicing early flowering 3 (elf3) allele of lentil is associated with yield enhancement under terminal heat stress.

There is a vast scope of area expansion of lentils after harvesting wet rice in South Asia. However, due to the photoperiod effect and terminal heat, the existing short-duration varieties failed to minimize yield loss under late-sown conditions. A mis-splicing causing A/G SNP present in the last nucleotide of exon 3 of early flowering 3 (ELF3) gene (elf3 allele) in a lentil line, L4710, is associated with the photoperiod insensitive flowering and the fast absolute growth rate (AGR). None of the Indian cultivars tested in this study, either early or late, possesses the non-functional elf3 allele. However, the A to G transition in ELF3-exon2 replaces glycine with aspartic acid at the 403rd amino acid in all the Indian varieties tested, compared to the reference sequence of Mediterranean accession, ILL5588. Therefore, targeting A/G SNP of exon 3, a PCR-based codominant marker is developed. The elf3 allele is correlated with the fast AGR and early flowering, but low yield and biomass, in an L4710 × LL56-derived RIL-population, compared to ELF3 carrying alleles when sown on 15th November. However, in a month of delayed sowing (20th December), the same elf3-RILs revealed a higher yield and biomass with slower AGR Moreover, three elf3-carrying lines, grown in delayed condition (20 December) for two consecutive years in three locations, outyielded three popular high-yielding cultivars that carry functional ELF3. Thus, elf3-carrying high-yielding lines could be the breeder's choice to expand and enhance lentil yield in short-season environments and in vast rice fallows of south Asia, where delayed rice harvest occurs frequently.

Rice (Oryza sativa) alleviates photosynthesis and yield loss by limiting specific leaf weight under low light intensity.

The physiological mechanisms of shade tolerance and trait plasticity variations under shade remain poorly understood in rice (Oryza sativa L.). Twenty-five genotypes of rice were evaluated under open and shade conditions. Various parameters to identify variations in the plasticity of these traits in growth irradiance were measured. We found wide variations in specific leaf weight (SLW) and net assimilation rate measured at 400µmolm-2 s-1 photosynthetic photon flux density (PPFD; referred to as A 400 ) among the genotypes. Under shade, tolerant genotypes maintained a high rate of net photosynthesis by limiting specific leaf weight accompanied by increased intercellular CO2 concentration (C i ) compared with open-grown plants. On average, net photosynthesis was enhanced by 20% under shade, with a range of 2-30%. Increased accumulation of biomass under shade was observed, but it showed no correlation with photosynthetic plasticity. Chlorophyll a /b ratio also showed no association with photosynthetic rate and yield. Analysis of variance showed that 11%, 16%, and 37% of the total variance of A 400 , SLW, and C i were explained due to differences in growth irradiance. SLW and A 400 plasticity in growth irradiance was associated with yield loss alleviation with R 2 values of 0.37 and 0.16, respectively. Biomass accumulation was associated with yield loss alleviation under shade, but no correlation was observed between A 400 and leaf-N concentration. Thus, limiting specific leaf weight accompanied by increased C i rather than leaf nitrogen concentration might have allowed rice genotypes to maintain a high net photosynthesis rate per unit leaf area and high yield under shade.

Co-Application of Silicate and Low-Arsenic-Accumulating Rice Cultivars Efficiently Reduces Human Exposure to Arsenic-A Case Study from West Bengal, India.

We investigated the effect of practically realizable doses of silicate on arsenic (As) uptake by differential-As-accumulating rice cultivars grown on geogenically As-polluted soil. The possible health risk from the dietary ingestion of As through rice was also assessed. In addition, a solution culture experiment was conducted to examine the role of root-secreted weak acids in differential As acquisition by rice cultivars. When grown without silicate, Badshabhog accumulated a much smaller amount of As in grain (0.11 mg kg-1) when compared to the other three varieties. Satabdi, IR-36, and Khitish accumulated As in grain beyond the permissible limit (0.2 mg kg-1) for human consumption. The application of silicate effectively reduced the As content in the grain, husk, and straw of all of the cultivars. The grain As content fell to 17.2 and 27.6% with the addition of sodium metasilicate at the rates of 250 and 500 mg kg-1, respectively. In the case of Khitish, the grain As content was brought down within permissible limits by the applied silicate (500 mg kg-1). The integrated use of low-As-accumulating cultivars and silicate has great potential to reduce the public health risks associated with As. A positive correlation between root-secreted total weak acid and grain As content could explain the different rice cultivars' differential As acquisition capacity.

Numerical study supplemented with simplified model on electrophoresis of a hydrophobic colloid incorporating finite ion size effects and ion-solvent interactions.

We consider a modified electrokinetic model to study the electrophoresis of a hydrophobic particle by considering the finite sized ions. The mathematical model adopted in this study incorporates the ion steric repulsion, ion-solvent interactions as well as Maxwell stress on the electrolyte. The dielectric permittivity and viscosity of the electrolyte is considered to vary with the local ionic volume fraction. Based on this modified model for the electrokinetics we have analyzed the electrophoresis in a single as well as mixture of electrolytes of monovalent and non- z : z $z:z$ electrolytes. The dependence of viscosity on local ionic volume fraction modifies the hydrodynamic drag as well as diffusivity of ions, which are ignored in existing studies on electrophoresis. A simplified model for electrophoresis of a hydrophobic particle incorporating the ion steric repulsion and ion-solvent interactions is developed based on the first-order perturbation on applied electric field. This simplified model is established to be efficient for a Debye layer thinner than the particle size and a smaller range of slip length. This model can be implemented for any number of ionic species as well as non- z : z $z:z$ electrolytes. It is established that the ion steric interactions and dielectric decrement creates a counterion saturation in the Debye layer leading to an enhanced mobility compared to the standard model. However, experimental data for non-dilute cases often under predicts the theoretically determined mobility. The present modified model fills this lacuna and demonstrate that the consideration of finite ion size modifies the medium viscosity and hence, ionic mobility, which in combination lowers the mobility value.

Radiosensitivity of seedling traits to varying gamma doses, optimum dose determination and variation in determined doses due to different time of sowings after irradiation and methods of irradiation in faba bean genotypes.

PURPOSE: Three experiments were conducted to assess the effect of different doses of gamma radiation on various seedling traits; determine the optimum doses of gamma radiation for different faba bean genotypes; find out the variation in optimum doses with respect to the different times of sowings after irradiation and methods of irradiation. MATERIALS AND METHODS: Five faba bean genotypes viz., L-2013-060, L-2013-092, Anandnagar Local, Gazipur Local and Bangla Gangachar were used in these experiments. In Experiment I, seeds of five experimental genotypes were exposed to different doses (100 Gy 200 Gy, 300 Gy, 400 Gy, 500 Gy, 600 Gy, 700 Gy and 800 Gy) of gamma radiation and were sown immediately after irradiation. In Experiment II, seeds of Bangla Gangachar and L-2013-060 were exposed to varying doses (100-800 Gy) of gamma radiation and were sown at seven sowings starting from 0 h to 24 h at 4-h intervals after irradiation. In Experiment III, L-2013-092 genotypes was exposed to different doses (100 -800 Gy) of gamma radiation with two different methods of irradiation. RESULTS: In Experiment I, the lethal dose 50 (LD50) values have arrived at 140 Gy, 669 Gy, 575 Gy, 386 Gy and 158 Gy for L-2013-060, L-2013-092, Anandnagar Local, Gazipur Local and Bangla Gangachar, respectively. The growth reduction 50 (GR50) doses for different seedling traits ranged from 130 Gy to 320 Gy for L-2013-060, 250 Gy to 480 Gy for L-2013-092, 130 Gy to 370 Gy for Anandnagar Local, 200 Gy to 350 Gy for Gazipur Local and 250 Gy to 400 Gy for Bangla Gangachar. In Experiment II, the values for LD50 of the genotypes Bangla Gangachar and L-2013-060 were significantly singular for different time intervals of sowing. The values of GR50 for most of the seedling traits were found to increase with the delay in sowing after irradiation from 4 to 24 h when compared with the immediately sown seed lots. In Experiment III, LD50 for L-2013-092 was 337 Gy with Method 1 and 669 Gy with Method 2. In Method 1, most of the growth parameters attained GR50 doses lower than Method 2. The first method was found to increase the radiosensitivity of L-2013-092. CONCLUSION: Every experimental genotype used in these three experiments showed dose-dependent retardation of different seedling traits. These optimized doses may be employed to establish mutant populations for exploiting the novel traits of faba bean. The time of sowing after irradiation and method of irradiation was found to be essential for confirming optimum doses.

Demonstration of the Holonomically Controlled Non-Abelian Geometric Phase in a Three-Qubit System of a Nitrogen Vacancy Center.

The holonomic approach to controlling (nitrogen-vacancy) NV-center qubits provides an elegant way of theoretically devising universal quantum gates that operate on qubits via calculable microwave pulses. There is, however, a lack of simulated results from the theory of holonomic control of quantum registers with more than two qubits describing the transition between the dark states. Considering this, we have been experimenting with the IBM Quantum Experience technology to determine the capabilities of simulating holonomic control of NV-centers for three qubits describing an eight-level system that produces a non-Abelian geometric phase. The tunability of the geometric phase via the detuning frequency is demonstrated through the high fidelity (~85%) of three-qubit off-resonant holonomic gates over the on-resonant ones. The transition between the dark states shows the alignment of the gate's dark state with the qubit's initial state hence decoherence of the multi-qubit system is well-controlled through a π/3 rotation.

Recent advances in the bioremediation of arsenic-contaminated soils: a mini review.

The carcinogenic metalloid arsenic (As), owing to its persistent behavior in elevated levels in soils, aggravates environmental and human health concerns. The current strategies used in the As decontamination involve several physical and chemical approaches. However, it involves high cost and even leads to secondary pollution. Therefore, it is quite imperative to explore methods that can eradicate As menace from the environment in an eco-friendly, efficient, and cost-competitive way. Searching for such viable alternatives leads to the option of bioremediation technology by utilizing various microorganisms, green plants, enzymes or even their integrated methods. This review is intended to give scientific and technical details about recent advances in the bioremediation strategies of As in soil. It takes into purview the extent, toxicological manifestations, pathways of As exposure and exemplifies the substantive need of bioremediation technologies such as phytoremediation and biosorption in a descriptive manner. Additionally, the paper looks into the wide potential of some plant growth promoting microorganisms (PGPMs) that improve plant growth on one hand and alleviate As toxicity on the other. Furthermore, it also makes a modest attempt to assimilate the use of nanoparticles, non-living biomass and transgenic crops which are the emerging alternative bioremediation technologies.

Conventional and new-breeding technologies for improving disease resistance in lentil (Lens culinaris Medik).

Lentil, an important cool season food legume, is a rich source of easily digestible protein, folic acid, bio-available iron, and zinc nutrients. Lentil grows mainly as a sole crop in the winter after harvesting rice in South Asia. However, the annual productivity is low due to its slow growth during the early phase, competitive weed infestation, and disease outbreaks during the crop growth period. Disease resistance breeding has been practiced for a long time to enhance resistance to various diseases. Often the sources of resistance are available in wild crop relatives. Thus, wide hybridization and the ovule rescue technique have helped to introgress the resistance trait into cultivated lentils. Besides hybridization, induced mutagenesis contributed immensely in creating variability for disease tolerance, and several disease-resistant mutant lines have been developed. However, to overcome the limitations of traditional breeding approaches, advancement in molecular marker technologies, and genomics has helped to develop disease-resistant and climate-resilient lentil varieties with more precision and efficiency. This review describes types of diseases, disease screening methods, the role of conventional and new breeding technologies in alleviating disease-incurred damage and progress toward making lentil varieties more resilient to disease outbreaks under the shadow of climate change.

Resonant Nanopumps: ac Gate Voltages in Conical Nanopores Induce Directed Electrolyte Flow.

Inducing transport in electrolyte-filled nanopores with dc fields has led to influential applications ranging from nanosensors to DNA sequencing. Here we use the Poisson-Nernst-Planck and Navier-Stokes equations to show that unbiased ac fields can induce comparable directional flows in gated conical nanopores. This flow exclusively occurs at intermediate driving frequencies and hinges on the resonance of two competing timescales, representing space charge development at the ends and in the interior of the pore. We summarize the physics of resonant nanopumping in an analytical model that reproduces the results of numerical simulations. Our findings provide a generic route toward real-time controllable flow patterns, which might find applications in controlling the translocation of small molecules or nanocolloids.

One-time Electromagnetic Irradiation Modifies Stress-sensitive Gene Expressions in Rice Plant.

Electromagnetic energy is utilized over multiple frequency bands to provide seamless wireless communication services. Plants can well perceive electromagnetic energy present in open environment due to reasonably high permittivity and electrical conductivity of constituent tissues. Moreover, higher surface-to-volume ratio of plant structure facilitates increased interaction with the incident electromagnetic waves. To date, a few well-designed studies have been conducted inside controlled electromagnetic reverberation chambers to investigate either short duration-low amplitude or long duration-periodic electromagnetic irradiation-induced molecular responses in plants. However, as far as is known, studies investigating molecular responses particularly at the mid-vegetative stage in plants following one-time (hours-long) electromagnetic irradiation have not been reported earlier. Hence, the present study aimed at investigating molecular responses in 40-day-old Swarnaprabha rice plants following one-time 1837.50 MHz, 2.75 mW/m2 electromagnetic irradiation of 2 h 30 min duration. Controlled electromagnetic irradiation inside a simple reverberation chamber was ensured to achieve pure electromagnetic environment at 1837.50 MHz with deterministic electromagnetic power density at selected position. Swarnaprabha rice plant was chosen for this investigation since the rice variety is widely cultivated and consumed in the Indian subcontinent. Subsequent alterations in some selected stress-sensitive gene expressions were assayed using real-time quantitative polymerase chain reaction technique-significant upregulation in calmodulin and phytochrome B gene expressions were noted. This investigation was purposefully focused on subsequent molecular responses immediately following electromagnetic irradiation so that the possible effects of secondary stimulations could be avoided. Observed molecular responses strongly suggested that plants perceive 1837.50 MHz, 2.75 mW/m2 electromagnetic irradiation similar to other injurious stimuli. © 2021 Bioelectromagnetics Society.

Yield-enhancing SPIKE allele from the aus-subtype indica rice and its allele specific codominant marker.

Improving spikelet number without limiting panicle number is an important strategy to increase rice productivity. In this study, a spikelet number enhancing SPIKE-allele was identified from the aus subtype indica rice, cv. Bhutmuri, which has an identical japonica like corresponding sequence including a retrotransposon sequence, usually absent in indica genotypes, like IR64. An allele-specific singletube PCR-based codominant marker targeting an A/G single-nucleotide polymorphism (SNP) at the 3'UTR was identified for easier genotyping. The yield enhancing ability of the Bhutmuri-SPIKE allele carrying RILs and NILs over IR64-SPIKE allele carrying alleles was due to increased number of filled grains/panicle. More than three times higher abundance of SPIKE transcripts was observed in Bhutmuri and NILs carrying this allele compared with IR64 and its allele carrying NILs. Higher rate of photosynthesis at more than 900 µmolm-2s-1 light intensity and more than six small vascular bundles between the two large vascular bundles in the flag leaves of Bhutmuri and its allele carrying NILs were also observed. The identified SPIKE allele and the marker associated with it will be useful for increasing the productivity of rice by marker-assisted breeding.

Investigation of arsenic-resistant, arsenite-oxidizing bacteria for plant growth promoting traits isolated from arsenic contaminated soils.

The problem of arsenic (As) pollution being severe warrants opting for low-cost microbial remediation strategies. The present study of identifying suitable bacterial strains led to the isolation of eleven As-tolerant strains from the As-contaminated rhizosphere soils of West Bengal, India. They were found to oxidize/reduce 55-31.6% of 5 mM As(III) and 73-37.6% of 5 mM As(V) within 12 h. The four isolates (BcAl-1, JN 73, LAR-2, and AR-30) had a high level of As(III) oxidase activity along with a higher level of As(V) and As(III) resistance. The agar diffusion assay of the isolates further confirmed their ability to endure As stress. The presence of aoxB gene was observed in these four As(III) oxidizing isolates. Evaluation of plant growth-promoting characteristics revealed that BcAl-1 (Burkholderia cepacia), JN 73 (Burkholderia metallica), AR-30 (Burkholderia cenocepacia), and LAR-2 (Burkholderia sp.) had significant plant growth-promoting characteristics (PGP), including the ability to solubilize phosphate, siderophore production, indole acetic acid-like molecules production, ACC deaminase production, and nodule formation under As stressed condition. BcAl-1 and JN 73 emerged as the most promising traits in As removal as well as plant growth promotion.

Atomically resolved 3D structural reconstruction of small quantum dots.

Semiconducting quantum dots (QDs) have potential applications in light-emitting diodes, single-photon sources and quantum computing due to shape-dependent (opto) electronic properties. Atomic resolution 3D-structure determination is important in understanding growth kinetics and improving device performance. 3D-reconstruction of large QDs was reported using characterization techniques like atomic force microscopy, atom probe tomography and tilt series electron tomography, but, still, atomic resolution tomography of QDs, especially those sized below 10 nm, is a challenge. Inline-3D-holography is an emerging and promising technique to perform atomic resolution tomography at low electron doses. In the present study, atomically resolved 3D structures of QDs were reconstructed using inline-3D-holography, implemented on InN QDs (<10 nm) grown on a Si substrate. The residual amorphous glue distorts the exit surface geometry; hence an error correction method was proposed. This is the first experimental evidence of pre-pyramid shaped 3D structure of QDs sized below 10 nm that supports theoretical predictions.

Charge Selectivity of an Ionic Transistor.

The charge selective properties of a long planar nanochannel with an embedded finite uniformly charged section in the middle are studied. The probability flux of a single test ion initially confined to the inlet reservoir is determined by integrating the Smoluchowski equation using a previously published series solution for the Debye-Hückel potential in this geometry. The charge selective properties are characterized by a dimensionless quantity that we call the "fractional blockage". We study how the fractional blockage depends on the dimensionless parameters that characterize the charge state and channel geometry. In the limit of strongly overlapped wall Debye layers, analytical expressions for the fractional blockage are presented that are found to be in good agreement with numerically computed values in the appropriate asymptotic regimes. These results may be helpful in the design of nanofluidic devices that have a variety of applications.