Length Modulation Research Articles

Tuning the Selectivity of Dendron Micelles Through Variations of the Poly(ethylene glycol) Corona

Engineering controllable cellular interactions into nanoscale drug delivery systems is key to enable their full potential. Here, using folic acid (FA) as a model targeting ligand and dendron micelles (DM) as a nanoparticle (NP) platform, we present a comprehensive experimental and modeling investigation of the structural properties of DMs that govern the formation of controllable, FA-mediated cellular interactions. Our experimental results demonstrate that a high level of control over the specific cell interactions of FA-targeted DMs can be achieved through modulation of the PEG corona length and the FA content. Using various molecular weight PEGs (0.6K, 1K, and 2K g/mol) and contents of dendron-FA conjugate incorporated into DMs (0, 5, 10, 25 wt %), the cell interactions of the targeted DMs could be controlled to exhibit minimal to >25-fold enhancement over nontargeted DMs. Molecular dynamics simulations indicated that structural characteristics, such as solvent accessible surface area of FA, local PEG density near FA, and FA mobility, account in part for the experimental differences in cellular interactions. The molecular structure that allows FA to depart from the surface of DMs to facilitate the initial cell surface binding was revealed to be the most important contributor for determining FA-mediated cellular interactions of DMs. The modular properties of DMs in controlling their specific cell interactions support the potential of DMs as a delivery platform and offer design cues for future development of targeted NPs.

ANNIHILATION OF COHOMOLOGY, GENERATION OF MODULES AND FINITENESS OF DERIVED DIMENSION

Let $(R,\m,k)$ be a commutative noetherian local ring of Krull dimension $d$. We prove that the cohomology annihilator $\ca(R)$ of $R$ is $\m$-primary if and only if for some $n\ge0$ the $n$-th syzygies in $\mod R$ are constructed from syzygies of $k$ by taking direct sums/summands and a fixed number of extensions. These conditions yield that $R$ is an isolated singularity such that the bounded derived category $\db(R)$ and the singularity category $\ds(R)$ have finite dimension, and the converse holds when $R$ is Gorenstein. We also show that the modules locally free on the punctured spectrum are constructed from syzygies of finite length modules by taking direct sums/summands and $d$ extensions. This result is exploited to investigate several ascent and descent problems between $R$ and its completion $\widehat R$.

A low-distortion CMOS analogue voltage follower for high-speed ADCs

This paper presents a low-distortion CMOS analogue voltage follower for high-speed medium-bit analog-to-digital converters (ADCs). The improved circuit is based on a wideband fully differential source-follower configuration. To eliminate the channel length modulation, lower-threshold cascode transistors are adopted. Furthermore, the body effect is removed by quasi-floating bulk (QFB) technique. Therefore, the linearity of the proposed source follower is superior to the conventional ones. The improved circuit has been designed and simulated by SPECTRE with a standard BSIM4 65nm CMOS technology. It achieves over 68dB spurious free dynamic range (SFDR) with a 1.2Vpp 1GHz differential sinusoid input signal. The circuit consumes 2.6mW with a 1.8V power supply.

Tradeoff Between Low-Power Operation and Radiation Hardness of Fully Depleted SOI pMOSFET by Changing LDD Conditions

The interrelation between off-leakage as consideration of low-power operation and X-ray radiation hardness has been evaluated in view of optimizing the lightly doped drain (LDD) concentration of fully depleted silicon-on-insulator pMOSFET. The MOSFET with relatively low LDD concentration called ultralow-power P channel LDD (ULP-PLDD) shows a lower off-leakage of 0.1 pA/ $\mu \text{m}$ but limited X-ray radiation tolerance, such that the drain current is reduced by $\sim 80$ % after 112-kGy(Si) X-ray irradiation due to radiation-induced gate length modulation (RIGLEM), while the MOSFET with six times higher LDD concentration called radiation-hardened PLDD (RH-PLDD) shows much higher radiation tolerance that the drain current reduction is $\sim 20$ % for the same radiation dose because of RIGLEM improvement by the elimination of the offset structure employed in ULP-PLDD. The off-leakage of RH-PLDD is one order of magnitude higher than that of ULP-PLDD as $\mu \text{m}$ . It is shown that there is such a tradeoff between low-power operation and radiation hardness.

A LTPS-TFT pixel circuit for active matrix organic light emitting diode based on improved current mirror

In this paper, a voltage-driving and current compensation method for active matrix organic light emitting diode (AMOLED) displays is proposed. An improved current mirror is introduced into the pixel circuit to overcome the channel length modulation effect of TFTs. The SPICE simulation results show that the proposed pixel circuit not only effectively compensates for non-idealities related with deviations of μ and VT in TFTs, the OLED degradation, but also offers a less setting time and guarantees a good liner relationship between VDATA and IOLED.

Singular Curves and Quasi-hereditary Algebras

In this article we construct a categorical resolution of singularities of an excellent reduced curve X, introducing a certain sheaf of orders on X. This categorical resolution is shown to be a recollement of the derived category of coherent sheaves on the normalization of X and the derived category of finite length modules over a certain artinian quasi–hereditary ring Q depending purely on the local singularity types of X. Using this technique, we prove several statements on the Rouquier dimension of the derived category of coherent sheaves on X. Moreover, in the case X is rational and projective we construct a finite dimensional quasi–hereditary algebra Λ such that the triangulated category Perf(X) embeds into D(Λ −mod) as a full subcategory.

Charge-based compact analytical model for triple-gate junctionless nanowire transistors

A new compact analytical model for short channel triple gate junctionless transistors is proposed. Based on a previous model for double-gate transistors which neglected the fin height effects, a new 3-D continuous model has been developed, including the dependence of the fin height and the short channel effects. An expression for threshold voltage is presented. The model defines a one-dimensional semiconductor effective capacitance due to the width and the height of the fin, which in turn redefines the potentials and charges, without altering the general modeling procedure. Threshold voltage roll-off, subthreshold slope, DIBL and channel length modulation, as well as, the mobility degradation and the velocity saturation have been introduced into the model. The validation was done by 3-D numerical simulations for different fin heights and channel lengths, as well as, by experimental measurements in nanowire transistors with doping concentrations of 5×1018 and 1×1019cm−3. The developed model is suitable for describing the current–voltage characteristics in all operating regions from double-gate to nanowire transistor with only 8 adjusting parameters.

PDMS-coated fiber volatile organic compounds sensors

The functionality of poly(dimethylsiloxane) (PDMS)-based interferometric fiber sensors for volatile organic compounds (VOCs) detection is investigated and experimentally demonstrated. Two interferometric configurations are considered in this work, namely Fabry-Perot (FP) and Sagnac interferometers (SI). Both sensors are functionalized with a thin layer of VOC-sensitive polymer: PDMS, whose degree of swelling varies as a function of VOC concentrations. This swelling effect will result in an optical path length and birefringence modulation for FP and SI sensors, respectively. In this paper, the two common VOCs, ethanol and 2-propanol, were detected by the proposed sensor and the inverse matrix method was used to differentiate the VOC in gas mixture.

Almost relative injective modules

The concept of a module $M$ being almost $N$-injective, where $N$ is some module, was introduced by Baba (1989). For a given module $M$, the class of modules $N$, for which $M$ is almost $N$-injective, is not closed under direct sums. Baba gave a necessary and sufficient condition under which a uniform, finite length module $U$ is almost $V$-injective, where $V$ is a finite direct sum of uniform, finite length modules, in terms of extending properties of simple submodules of $V$. Let $M$ be a uniform module and $V$ be a finite direct sum of indecomposable modules. Some conditions under which $M$ is almost $V$-injective are determined, thereby Baba's result is generalized. A module $M$ that is almost $M$-injective is called an almost self-injective module. Commutative indecomposable rings and von Neumann regular rings that are almost self-injective are studied. It is proved that any minimal right ideal of a von Neumann regular, almost right self-injective ring, is injective. This result is used to give an example of a von Neumann regular ring that is not almost right self-injective.

Theoretical analysis of optimum adiabatic tapering length and pulse shape modulation along tapered multimode fiber

In this paper, Helmholtz equation for large core tapered fiber has been solved by using beam propagation method. The evolution of Gaussian input field, electric field and electric power at different linear tapering length have been studied. As an importance of adiabatic optical field transmission along tapered length, minimum tapering length has been obtained for this great task. Also, because of importance of transverse electric field distribution at the output of the tapered segment, the minimum tapering length for this purpose has been obtained.

Quantum-state transfer in staggered coupled-cavity arrays

We consider a coupled-cavity array, where each cavity interacts with an atom under the rotating-wave approximation. For a staggered pattern of intercavity couplings, a pair of field normal modes, each bilocalized at the two array ends, arises. A rich structure of dynamical regimes can hence be addressed, depending on which resonance condition is set between the atom and the field modes. We show that this can be harnessed to carry out high-fidelity quantum-state transfer (QST) of photonic, atomic, or polaritonic states. Moreover, by partitioning the array into coupled modules of shorter length, the QST time can be substantially shortened without significantly affecting the fidelity.

Modulation of primary cilia length by melanin-concentrating hormone receptor 1

Melanin-concentrating hormone (MCH) receptor 1 (MCHR1) is a class A G-protein-coupled receptor (GPCR). The MCH-MCHR1 system has been implicated in the regulation of feeding, emotional processing, and sleep in rodents. Recent work revealed that MCHR1 is selectively expressed in neuronal primary cilia of the central nervous system. Cilia have various chemosensory functions in many types of cell, and ciliary dysfunction is associated with ciliopathies such as polycystic kidney disease and obesity. Although dynamic modulation of neuronal cilia length is observed in obese mice, the functional interaction of neuronal ciliary GPCR and its endogenous ligand has not yet been elucidated. We report here that MCH treatment significantly reduced cilia length in hTERT-RPE1 cells (hRPE1 cells) transfected with MCHR1. Quantitative analyses indicated that MCH-induced cilia shortening progressed in a dose-dependent manner with an EC50 lower than 1nM when cells were treated for 6h. Although the assembly and disassembly of primary cilia are tightly coupled to the cell cycle, cell cycle reentry was not a determinant of MCH-induced cilia shortening. We confirmed that MCH elicited receptor internalization, Ca2+ mobilization, ERK and Akt phosphorylation, and inhibition of cyclic AMP accumulation in MCHR1-expressing hRPE1 cells. Among these diverse pathways, we revealed that Gi/o-dependent Akt phosphorylation was an important component in the initial stage of MCH-induced cilia length shortening. Furthermore, induction of fewer cilia by Kif3A siRNA treatment significantly decreased the MCH-mediated phosphorylation of Akt, indicating the functional importance of the MCHR1-Akt pathway in primary cilia. Taken together, the present data suggest that the MCH-MCHR1 axis may modulate the sensitivity of cells to external environments by controlling the cilia length. Therefore, further characterization of MCHR1 as a ciliary GPCR will provide a potential molecular mechanism to link cilia length control with obesity.

Junctionless Poly-Si Nanowire FET With Gated Raised S/D

The short-channel effect (SCE) is an important issue in CMOS technology. In this paper, a junctionless (JL) poly-Si nanowire FET (NW-FET) with gated raised source/drain (S/D) was demonstrated to suppress the SCE. The gated raised S/D structure enhances the control of the channel by the gate. Therefore, a JL poly-Si NW-FET with the gated raised S/D exhibits reduced drain-induced barrier lowering and less channel length modulation effect. Additionally, when the gate bias exceeds the flat-band voltage, a JL poly-Si NW-FET with gated raised S/D exhibits a low parasitic S/D resistance owing to the formation of an accumulation layer in its S/D, which is useful for multi-gate-oxide applications. However, the gated raised S/D shows a high gate-induced drain leakage current in the off state. Therefore, the gate electrode of the gated raised S/D must be designed carefully to prevent high off current.

Fundamental Study of Influence of Ripple Noise From DC–DC Converter on Spurious Noise of Wireless Portable Equipment

Power supply noise is a serious concern in noise-sensitive radio frequency or analog circuits. This paper presents an analysis of the influence of the synchronous rectification buck-type dc–dc converters for power amplifiers. An output ripple noise equation of the converter and a spurious noise equation of the carrier output voltage of the class-A amplifier powered by the converter are derived to analyze fundamental characteristics of these noise components theoretically. The amplifier's output spurious noise is calculated by these equations and measured by the evaluation circuit board. The spurious noise variation caused by the parameter variations of the amplifier or the converter is discussed based on these experimental and theoretical results. The spurious noise can be suppressed by decreasing the channel length modulation coefficient of the n-channel MOSFET constituting the amplifier and the natural frequency of the converter output LC filter. The spurious noise is reduced to low level below − 60 dB compared to the carrier signal by setting the channel length modulation coefficient below 0.1 V−1 and the natural frequency below 120 kHz. Furthermore, when the natural frequency is below 40 kHz, the spurious noise is − 80 dB below the carrier signal.

The Global Dimension of the full Transformation Monoid (with an Appendix by V. Mazorchuk and B. Steinberg)

The representation theory of the symmetric group has been intensively studied for over 100 years and is one of the gems of modern mathematics. The full transformation monoid \(\mathfrak {T}_{n}\) (the monoid of all self-maps of an n-element set) is the monoid analogue of the symmetric group. The investigation of its representation theory was begun by Hewitt and Zuckerman in 1957. Its character table was computed by Putcha in 1996 and its representation type was determined in a series of papers by Ponizovskiĭ, Putcha and Ringel between 1987 and 2000. From their work, one can deduce that the global dimension of \(\mathbb {C}\mathfrak {T}_{n}\) is n−1 for n = 1, 2, 3, 4. We prove in this paper that the global dimension is n−1 for all n ≥ 1 and, moreover, we provide an explicit minimal projective resolution of the trivial module of length n−1. In an appendix with V. Mazorchuk we compute the indecomposable tilting modules of \(\mathbb {C}\mathfrak T_{n}\) with respect to Putcha’s quasi-hereditary structure and the Ringel dual (up to Morita equivalence).

A Study of Traditional and Surrounding Gate MOSFET using TCAD Simulations

In this paper, Traditional and surrounding gate MOSFET are simulated using TCAD Silvaco and report the effect of multigate transistor. As the channel length of transistors is scaling down, a traditional MOSFET suffers from short channel effects and degrade the device performance. The different parameter such as threshold voltage, area, subthreshold slope, channel length modulation and leakage current are extracted for traditional and surrounding gate MOSFET. The parameters obtained from surrounding gate MOSFET is compared with a traditional MOSFET of the same dimension. The Results show that better performance was obtained for surrounding gate MOSFET. Its current drive capability is more as compared to traditional MOSFET .However, benefits of achieving superior performance with surrounding gate MOSFET reduces in terms of poor RF performance. Hence, this paper concludes that surrounding gate MOSFET have huge potential to be a promising contender to the traditional MOSFETs for making of future generation low-power high speed devices which could minimize the occupied area.

Symmetric powers of Nat SL(2,𝕂)

Abstract In this paper, we identify the representations 𝕂 ⁢ [ X k , X k - 1 ⁢ Y , … , Y k ] ${\mathbb{K}[X^{k},X^{k-1}Y,\dots,Y^{k}]}$ among abstract ℤ ⁢ [ SL 2 ⁡ ( 𝕂 ) ] ${\mathbb{Z}[\operatorname{SL}_{2}(\mathbb{K})]}$ -modules. One result is on ℚ ⁢ [ SL 2 ⁡ ( ℤ ) ] ${\mathbb{Q}[\operatorname{SL}_{2}(\mathbb{Z})]}$ -modules of nilpotence length at most 5 and generalises a classical “quadratic” theorem by Smith and Timmesfeld; there are reasons to believe that this generalisation is close to optimal. Another result is on extending the linear structure on the module from the prime field to 𝕂 ${\mathbb{K}}$ . All proofs are by computation in the group ring using the Steinberg relations.

Short-term and long-term effects on visual word recognition.

Effects of lexical and sublexical variables on visual word recognition are often treated as homogeneous across participants and stable over time. In this study, we examine the modulation of frequency, length, syllable and bigram frequency, orthographic neighborhood, and graphophonemic consistency effects by (a) individual differences, and (b) item repetition. A group of 129 participants performed lexical decision and naming, in counterbalanced order, using a set of 150 Greek words in which these variables were decorrelated. Frequency, length, and syllable frequency effects were reduced by a preceding task. Length effects were inversely related to years of education. Neighborhood effects depended on the metric used. There were no significant effects or interactions of bigram frequency or consistency. The results suggest that exposure to a word causes transient effects that may cumulatively develop into permanent individual differences. Models of word recognition must incorporate item-specific learning to account for these findings.

Euler-Poincaré pairing, Dirac index and elliptic pairing for Harish-Chandra modules

Let G be a connected real reductive group with maximal compact subgroup K of equal rank, and let M be the category of Harish-Chandra modules for G. We relate three differentely defined pairings between two finite length modules X and Y in M : the Euler-Poincare pairing, the natural pairing between the Dirac indices of X and Y , and the elliptic pairing of [2]. (The Dirac index IDir(X) is a virtual finite dimensional representation of K, the spin double cover of K.) Analogy with the case of Hecke algebras studied in [7] and [6] and a formal (but not rigorous) computation lead us to conjecture that the first two pairings coincide. In the second part of the paper, we show that they are both computed as the indices of Fredholm pairs (defined here in an algebraic sense) of operators acting on the same spaces. We construct Euler-Poincare functions fX for any finite length Harish-Chandra module X. These functions are very cuspidal in the sense of Labesse, and their orbital integrals on elliptic elements coincide with the character of X. From this we deduce that the Dirac index pairing coincide with the elliptic pairing. These results are the archimedean analog of results of Schneider-Stuhler [21] for p-adic groups.

Self-Aligned Coplanar Top Gate In-Ga-ZnO Thin-Film Transistors Exposed to Various DUV Irradiation Energies

Self-aligned coplanar top gate indium–gallium–zinc-oxide thin-film transistors (TFTs), with source/drain (S/D) regions that were heavily doped by various deep-ultraviolet (DUV) irradiation energies at dual wavelengths of 185 and 254 nm, were investigated. The electrical performances of TFTs improved as the DUV irradiation energy increased. The proposed TFTs, with DUV irradiation of 20 J/cm2, have a field-effect mobility of 22.0 cm2/ $\text {V}\cdot \text {s}$ , a threshold voltage of 2.2 V, a subthreshold swing value of 0.24 V/decade, and an on/off current ratio of $1.34 \times 10^{6}$ . In addition, the channel length modulation ( $\Delta L$ ) and the width-normalized contact resistance ( $R_{\mathrm {SD}}W$ ) were 1.04 $\mu \text{m}$ and 60.5 $\Omega \cdot \text {cm}$ , respectively. Such short $\Delta L$ and low $R_{\mathrm {\mathbf {SD}}}W$ values indicate that the S/D regions were properly formed by the DUV irradiation. This simple and cost-effective doping technique can be useful for the fabrication of self-aligned TFTs.