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We describe the total synthesis of (−)-flueggenines D and I. This features the first total synthesis of dimeric Securinega alkaloids with a C(α)–C(δ′) connectivity between two monomeric units. The key dimerization was enabled by a sequence that involves Stille reaction and conjugate reduction. The high chemofidelity of the Stille reaction enabled us to assemble two structurally complex fragments that could not be connected by other methods. Stereochemical flexibility and controllability at the δ′-junction of the dimeric intermediate render our synthetic strategy broadly applicable to the synthesis of other high-order Securinega alkaloids., The first total synthesis of dimeric securinega alkaloids (−)-flueggenines D and I was completed by a dimerization strategy that involves Stille reaction and stereoselective conjugate reduction.

We have demonstrated the use of conductive polylactic acid (PLA) filament for dose monitoring in a syringe-less wearable infusion pump. A channel reservoir is inlaid with conductive PLA filament. As the liquid medium is dispensed via gas pressurization by an built-in electrolysis chamber, the effective impedance of the conductive PLA filament/liquid medium column changes as well. This allows the dispensed volume to be monitored via the output voltage across a series resistor. Using 5 V sinusoidal input voltage, the output voltage decreased from ∼1.3 to ∼0.13 V as the dispensed volume of 0.1 mol/L PBS increased from 0 to 1000 μL. Similarly, the output voltage for insulin analog decreased from ∼0.64 to 0.126 V for the same volume displaced. Repeated dispensing runs with 0.1 mol/L PBS showed good consistency (standard deviation less than 10 mV). The rate of change of the output voltage with elapsed time varied accordingly for the different flow rates (0.25–1.00 mL/h or ∼4–17 μL/min). At electrolysis voltages of 1.5 and 5 V, the respective output voltage were 1.04 and 0.33 V. These corresponded to flow rates of ∼3 and 10 mL/h (∼50 and 160 μL/ min).

The isolation of flueggenines A and B by Yue and co-workers in 2006 has triggered a burst of isolation reports of dimeric and oligomeric securinega alkaloid natural products. The compelling molecular structures of these compounds with various modes of connection between monomeric securinega units have posed intriguing challenges to the synthetic organic community. Herein, we have categorized high-order securinega alkaloids based on their biosynthetic mode of dimerization or oligomerization. We then have compiled all reported syntheses of dimeric securinega alkaloids based on our classification.1 Introduction2 Categorization of High-Order Securinega Alkaloid Natural Products3 Syntheses of Type I Dimeric Securinega Alkaloids4 Syntheses of Type II Dimeric Securinega Alkaloids5 Synthesis of Type III Dimeric Securinega Alkaloid6 Conclusion

In this paper, we investigated the hotcarrier injection (HCI) mechanism, one of the most important reliability issues, in 10 nm node Input/Output (I/O) bulk FinFET. The FinFET has much intensive HCI damage in Fin-bottom region, while the HCI damage for planar device has relatively uniform behavior. The local damage behavior in the FinFET is due to the geometrical characteristics. Also, the HCI is significantly affected by doping profile, which could change the worst HCI bias condition. This work suggested comprehensive understanding of HCI mechanisms and the guideline of doping profile in 10 nm node I/O bulk FinFET.

This paper presents an analysis of traps causing random telegraph noise (RTN) in trap-assisted tunneling (TAT) gate-induced drain leakage (GIDL) current. RTN was shown for the first time to occur as a result of electron trapping rather than hole trapping. In addition, the proper effective permittivity of two different materials is used to accurately determine the distance between two traps causing RTN in TAT GIDL in an oxide.

The first total synthesis of dimeric securinega alkaloid (−)-flueggenine C is completed via an accelerated intermolecular Rauhut–Currier (RC) reaction. Despite the numerous reports on the total synthesis of monomeric securinegas, the synthesis of dimeric securinegas whose monomeric units are connected by a putative enzymatic RC reaction has not been reported to date. We have found that installation of a nucleophilic functional group at the γ-position of an enone greatly accelerates the rate of the diastereoselective intermolecular RC reaction. This discovery enabled an efficient and selective formation of the dimeric intermediate which was further transformed to (−)-flueggenine C.

Carbohydrate-lectin interactions are important in many biological events. Endogenous cell-surface lectins are attractive markers for the recognition and targeting. Human ferritin protein cage nanoparticles (HFPCNs) are prepared as delivery nanoplatforms and two different types of monosaccharide derivatives; maleimido group terminated-mannopyranoside and galactopyranoside. Uniform and polyvalent displays of mannoses or galactoses on the surface of HFPCNs are achieved by using site-specific thiol-maleimide Michael-type addition. Mannose- or galactose-displaying HFPCNs recognize and tightly bind to DC-SIGN or ASGP-R lectins on the surface of the mammalian cells, DCEK or HepG2 cells.

This paper presents an analysis of the Random Telegraph Noise (RTN) of the Gate-Induced Drain Leakage (GIDL) of a Metal Oxide Semiconductor Field Effect Transistor (MOSFET). The RTN data that was measured and analytical equations are used to extract the values of the parameters for the vertical distance of the oxide trap from the interface and of the energy level of the interface trap. These values and equations allow for the distance r between the interface trap and the oxide trap to be extracted. For the first time, the accurate field enhancement factor γ(F), which depends on the magnitude of the electric field at the Si/SiO2 interface, was used to calculate the current ratio before and after the electron trapping, and the value extracted for r is completely different depending on the enhancement factor that is used.

Protein cages are spherical hollow macromolecules that are attractive platforms for the construction of nanoscale cargo delivery vehicles. Human heavy-chain ferritin (HHFn) is modified genetically to control the number and position of functional groups per cage. 24 β-CDs are conjugated precisely to the modified HHFn in specific locations through thiol-maleimide Michael-type addition followed by copper(I)-catalyzed azide/alkyne cycloaddition (CuAAC). The resulting human ferritins displaying β-CDs (β-CD-C90 HHFn) can form inclusion complexes with FITC-AD, which can slowly release the guest molecule reversibly in a buffer solution via non-covalent β-CD/AD interactions. β-CD-C90 HHFn can potentially be used as delivery vehicles for insoluble drugs.

Transparent and stretchable electronics with remarkable bendability, conformability, and lightness are the key attributes for sensing or wearable devices. Transparent and stretchable field-effect transistor sensors using graphene-metal nanowire hybrid nanostructures have high mobility (≈3000 cm(2) V(-1) s(-1) ) with low contact resistance, and they are transferrable onto a variety of substrates. The integration of these sensors for RLC circuits enables wireless monitoring.

Carbohydrate-lectin interactions are important in many biological events. Endogenous cell-surface lectins are attractive markers for the recognition and targeting. Human ferritin protein cage nanoparticles (HFPCNs) are prepared as delivery nanoplatforms and two different types of monosaccharide derivatives; maleimido group terminated-mannopyranoside and galactopyranoside. Uniform and polyvalent displays of mannoses or galactoses on the surface of HFPCNs are achieved by using site-specific thiol-maleimide Michael-type addition. Mannose- or galactose-displaying HFPCNs recognize and tightly bind to DC-SIGN or ASGP-R lectins on the surface of the mammalian cells, DCEK or HepG2 cells.

In this paper, we analyzed the amplitude of variable junction leakage currents caused by the interaction between two interface states in MOS transistors. For the first time, an analytical equation for the ratio between the junction leakage current before and after electron capture into the slow state was derived with consideration of both the change in the capture cross-section and the electric field. Also, the correct equation for the electric field after electron trapping was derived and used. The distance between the two interface states was extracted from the equation and measurement data. The extracted distance was interpreted under the framework of the inter-atomic distance in the silicon lattice structure at the Si/SiO2 interface.