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Cathelicidins are a primitive class of host defense peptides and are known for their broad–spectrum antimicrobial activity against bacteria, fungi, and enveloped viruses. These small, cationic, proteolytically–activated peptides are diverse in structure, encompassing a wide range of activities on host immune and inflammatory cell responses. The dual capacity of cathelicidins to directly control infection and regulate host defenses highlights the potential use of these peptides as alternatives to antibiotics and immunomodulators. Cathelicidins are found in many mammalian species; this review focuses on bovine cathelicidins. Eight naturally and two synthetically occurring bovine cathelicidins are described in detail, with a focus on recent advances in their expression, location and biological roles. This review also presents an overview of the bioactive functions of cathelicidins in bovine mastitis, a disease causing economic losses in cattle dairy production. Comparison of the structural, antimicrobial, cytotoxic and mechanistic properties of bovine cathelicidins advances the knowledge needed for the development of these peptides as potential identifiers of infectious diseases (e.g., bovine mastitis) and as novel therapeutic alternatives to antibiotics. [ABSTRACT FROM AUTHOR]

In this work, we propose a damascene process to fabricate embedded gold micro- and nano-structures at the same time. We present a systematic study of the material removal rate (MRR) and the selectivity on both gold and silicon dioxide. The embedded microstructures are 2 μm wide and 60 nm deep, while the nanostructures widths vary from 70 nm to 500 nm for a 50 nm depth. Moreover, we highlight the contribution of the CMP in polishing the surfaces of gold films. Morphological characterizations are performed using mechanical profilometry, Atomic Force Microscopy (AFM), and Scanning Electron Microscopy (SEM). MRR and selectivity are evaluated as a function of time, applied pressure, platen rotation speed, and slurry flow. [ABSTRACT FROM AUTHOR]

We present a versatile nanodamascene process for the realization of low-power nanoelectronic devices with different oxide junctions. With this process we have fabricated metal/insulator/metal junctions, metallic single electron transistors, silicon tunnel field effect transistors, and planar resistive memories. These devices do exploit one or two nanometric-scale tunnel oxide junctions based on TiO2, SiO2, HfO2, Al2O3, or a combination of those. Because the nanodamascene technology involves processing temperatures lower than 300°C, this technology is fully compatible with CMOS back-end-of-line and is used for monolithic 3D integration. [ABSTRACT FROM AUTHOR]

In this work, we demonstrate a silicon nanocrystal Field Effect Transistor (ncFET). Its operation is similar to that of a Tunnelling Field Effect Transistor (TFET) with two barriers in series. The tunnelling barriers are fabricated in very thin silicon dioxide and the channel in intrinsic polycrystalline silicon. The absence of doping eliminates the problem of achieving sharp doping profiles at the junctions, which has proven a challenge for large-scale integration and, in principle, allows scaling down the atomic level. The demonstrated ncFET features a 104 on/off current ratio at room temperature, a low 30 pA/μm leakage current at a 0.5 V bias, an on-state current on a par with typical all-Si TFETs and bipolar operation with high symmetry. Quantum dot transport spectroscopy is used to assess the band structure and energy levels of the silicon island. [ABSTRACT FROM AUTHOR]

We report the fabrication of Hf0.5Zr0.5O2 (HZO) based ferroelectric memory crosspoints using a complementary metal-oxide-semiconductor-compatible damascene process. In this work, we compared 12 and 56 µ m2 crosspoint devices with the 0.02 mm2 round devices commonly used as a benchmark. For all devices, a 9 nm thick ferroelectric thin film was deposited by plasma-enhanced atomic layer deposition on planarized bottom electrodes. The wake-up appeared to be longer for the crosspoint memories compared to 0.02 mm2 benchmark, while all the devices reached a 2Pr value of ∼50 µ C cm−2 after 105 cycles with 3 V/10 µ s squared pulses. The crosspoints stand out for their superior endurance, which was increased by an order of magnitude. Nucleation limited switching experiments were performed, revealing a switching time <170 ns for our 12 and 56 µ m2 devices, while it remained in the µ s range for the larger round devices. The downscaled devices demonstrate notable advantages with a rise in endurance and switching speed. [ABSTRACT FROM AUTHOR]

An approach to form a monolayer of organized silicon nanocrystals on a monocrystalline Si wafer is reported. Ordered arrays of nanoholes in a silicon nitride layer were obtained by combining electron beam lithography and plasma etching. Then, a short electrochemical etching current pulse led to formation of a single Si nanocrystal per each nanohole. As a result, high quality silicon nanocrystal arrays were formed with well controlled and reproducible morphologies. In future, this approach can be used to fabricate single electron devices. [ABSTRACT FROM AUTHOR]

In this study, a p-Si/ALD-Al2O3/Ti/Pt MOS (metal oxide semiconductor) device has been fabricated and used as a hydrogen sensor. The use of such a stack enables a reliable, industry-compatible CMOS fabrication process. ALD-Al2O3 has been chosen as it can be integrated into the back end of the line (BEOL) or in CMOS, post processing. The device response and recovery are demonstrated with good correlation between the capacitance variation and the hydrogen concentration. Detection down to 20 ppm at 140 °C was obtained and a response time of 56 s for 500 ppm was recorded. [ABSTRACT FROM AUTHOR]

• The performances of the inductor are critical in RF and quantum applications. • The inductance and the quality factor can be modified by modifying elements around the inductor. • The finite element method can be used to quantify the performances of magnetics structures. • Patterning the magnetics materials enhances the performance in high frequencies. This study investigates several ways to improve the quality factor and (or) the inductance by evaluating the possibility to add magnetic materials around an inductor integrated into the BEOL of CMOS technology. Performance boost evaluation is done through 3D numerical simulations of an inductor integrated on an SOI substrate made in a 28 nm UTBB FDSOI technology. The choice of materials and their design topologies are mainly the study parameters which leads to the selection of a solution according to the final application: RF for quantum. We demonstrate an ideal improvement of L by a factor 5 and of Q by a factor 3, and a realistic improvement of Q of 2-turn inductors by 25 % with a shield; 46 % with a patterned magnetic material; and a Q improvement of 1-turn inductor by 14 % with an HR substrate. [ABSTRACT FROM AUTHOR]

Exploration of memristors' behavior at cryogenic temperatures has become crucial due to the growing interest in quantum computing and cryogenic electronics. In this context, our study focuses on the characterization at cryogenic temperatures (4.2 K) of TiO2−x-based memristors fabricated with a CMOS-compatible etch-back process. We demonstrate a so-called cryogenic reforming (CR) technique performed at 4.2 K to overcome the well-known metal-insulator transition (MIT), which limits the analog behavior of memristors at low temperatures. This cryogenic reforming process was found to be reproducible and led to a durable suppression of the MIT. This process allowed to reduce by ∼20% the voltages required to perform DC resistive switching at 4.2 K. Additionally, conduction mechanism studies of memristors before and after cryogenic reforming from 4.2 to 300 K revealed different behaviors above 100 K, indicating a potential change in the conductive filament stoichiometry. The reformed devices exhibit a conductance level that is 50 times higher than ambient-formed memristor, and the conduction drop between 300 and 4.2 K is 100 times smaller, indicating the effectiveness of the reforming process. More importantly, CR enables analog programming at 4.2 K with typical read voltages allowing to store up to 4 bits of information on a single CR memristor. Suppressing the MIT improved the analog switching dynamics of the memristor leading to ∼250% larger on/off ratios during long-term depression (LTD)/long-term potentiation (LTP) resistance tuning. This enhancement opens up the possibility of using TiO2−x-based memristors to be used as synapses in neuromorphic computing at cryogenic temperatures. [ABSTRACT FROM AUTHOR]

Brachyspira hyodysenteriae , an etiologic agent of swine dysentery (SD), is known for causing colitis. Although some aspects of colonic defenses during infection have been described previously, a more comprehensive picture of the host and microbiota interaction in clinically affected animals is required. This study aimed to characterize multiple aspects of colonic innate defenses and microbiome factors in B. hyodysenteriae- infected pigs that accompany clinical presentation of hemorrhagic diarrhea. We examined colonic mucus barrier modifications, leukocyte infiltration, cathelicidin expression, as well as microbiome composition. We showed that B. hyodysenteriae infection caused microscopic hemorrhagic colitis with abundant neutrophil infiltration in the colonic lamina propria and lumen, with minor macrophage infiltration. Mucus hypersecretion with abundant sialylated mucus in the colon, as well as mucosal colonization by [Acetivibrio] ethanolgignens , Lachnospiraceae , and Campylobacter were pathognomonic of B. hyodysenteriae infection. These findings demonstrate that B. hyodysenteriae produces clinical disease through multiple effects on host defenses, involving alterations of mucosal innate immunity and microbiota. Given that B. hyodysenteriae is increasingly resistant to antimicrobials, this understanding of SD pathogenesis may lead to future development of non-antibiotic and anti-inflammatory alternative therapeutics. • B. hyodysenteriae caused hemorrhagic colitis with abundant neutrophils in the lamina propria and lumen. • Swine dysentery predisposed a mucus hypersecretion with abundant sialylated mucus in the colon. • Colonization by [Acetivibrio] ethanolgignens , Lachnospiraceae , and Campylobacter prevailed in B. hyodysenteriae infection. [ABSTRACT FROM AUTHOR]

Objectives: Traditional progestogen-only pills (POPs) have stringent daily timing and missed pill rules that might affect contraceptive reliability. A new-generation oestrogen-free pill has been developed, containing 4-mg drospirenone with a unique regimen of 24 active treatment days followed by four placebo tablets. A previous study showed that this new drospirenone-only pill effectively inhibited ovulation. Clinical efficacy, however, can be affected by compliance, and delayed or forgotten pill intake often occurs in daily life. The aim of this study was to investigate if inhibition of ovulation was maintained after four scheduled 24-h delays in tablet intake.Study Design: One hundred thirty healthy women with proven ovulatory cycles were randomized, and 127 were treated with the drospirenone-only pill during two cycles. In treatment Group A (n=62), 24-h delays in tablet intake were scheduled on days 3, 6, 11 and 22 during Cycle 2 and, in treatment Group B (n=65) during Cycle 1, respectively. Ovulation was defined as disappearance or persistence of a large follicle and progesterone levels higher than 5 ng/mL for at least 5 consecutive days.Results: The overall ovulation rate was 0.8%; only one subject in Group A fulfilled the ovulation criteria in Cycle 2. Follicular diameters in the regular-intake and the delayed-intake cycles were similar.Conclusion: Despite the 4-day hormone-free period and multiple intentional 24-h delays in tablet intake, ovulation inhibition was maintained. This property distinguishes this new-generation oestrogen-free pill from traditional POPs by allowing the same "safety window" or flexibility in intake as combined oral contraceptives without compromising contraceptive reliability.Implications: Delayed or forgotten pill intake is very common. Ovulation inhibition by the new-generation oestrogen-free pill, containing 4-mg drospirenone for 24 days followed by a 4-day treatment-free period, was maintained despite four 24-h delays in tablet intake, so the impact of delayed intake on contraceptive reliability will be low. [ABSTRACT FROM AUTHOR]

ObjectivesProgestogen-only pills (POPs) are safer with respect to cardiovascular risks than contraceptives containing estrogens. Despite the increased contraceptive efficacy of a desogestrel-only pill compared with a traditional POP, POPs are still not widely used due to an unpredictable bleeding pattern. A new POP containing 4 mg drospirenone has been developed with a 24/4 intake regimen which may improve the bleeding pattern. The objectives of this study were to investigate ovulation inhibition with the new drospirenone-only pill in comparison with the desogestrel-only pill and, in addition, to assess the effects on cervical mucus permeability and bleeding. MethodsSixty-four healthy volunteers with proven ovulatory cycles were randomised and treated with either the drospirenone-only or the desogestrel-only pill during two 28-day cycles. Follicular diameter, endometrial thickness, and serum estradiol (E2) and progesterone concentrations were measured and Hoogland scores were determined. Additionally, cervical mucus scores, bleeding and return of ovulation were assessed. ResultsBoth treatments effectively inhibited ovulation. Follicular diameter, E2levels and Hoogland scores were equal, demonstrating efficient ovarian suppression. One subject in each group had a Hoogland score of 6, but the criteria for normal luteal activity were not fulfilled. In both groups, ovulation did not occur before day 9 of the post-treatment cycle. Cervical mucus permeability was suppressed in both groups. The median number of bleeding and spotting days was lower in the drospirenone group. ConclusionsThe new drospirenone-only pill inhibited ovulation as effectively as the desogestrel-only pill despite the 4-day hormone-free interval. Chinese Abstract 摘要 目的对于心血管疾病风险，纯孕激素避孕药比含雌激素的避孕药安全。尽管只含去氧孕烯的避孕药与传统纯激素避孕药相比，避孕效果增加了，由于不可预知的出血模式，纯孕激素避孕药仍没有被广泛应用。包含4毫克屈螺酮的新型纯孕激素避孕药已被研制出，采用24/4方案可以改善出血模式。这项研究的目的是调查仅含屈螺酮的新型避孕药与仅含去氧孕烯的避孕药相比对排卵抑制的情况，此外，也用于评估对宫颈粘液穿透性和出血的影响。 方法经过验证有排卵周期的64名健康志愿者，在两个28天的周期中被随机给予仅含屈螺酮或者去氧孕烯的避孕药。测定卵泡直径、子宫内膜厚度、血清雌二醇和孕激素浓度，并进行Hoogland评分。此外，对宫颈粘液评分、出血及排卵抑制进行评估。 结果两种治疗方法都能有效的抑制排卵。卵泡直径、雌二醇水平和Hoogland评分都是相同的，以及证明有效的排卵抑制。每组每一项的Hoogland评分都是6，但是黄体活动的标准还没有制定。在预处理周期的第9天以前，两个组都不会出现排卵。两个组的宫颈粘液穿透性都被抑制了。在屈螺酮组中，黄体期出血天数的中位数比较低。 结论尽管有4天无激素的时间间隔，仅含屈螺酮的新型避孕药与仅含去氧孕烯的避孕药对排卵的抑制效果是一样的。 关键词 去氧孕烯片；去氧孕烯；屈螺酮；卵巢活动；排卵抑制；纯孕激素型避孕药 [ABSTRACT FROM PUBLISHER]

Objectives: This study was performed to assess the contraceptive efficacy of the drospirenone (DRSP)-only pill and to provide information regarding its safety and cycle-control profile.Study Design: This prospective, multicenter, noncomparative study was conducted at 41 European sites in healthy women at risk of pregnancy, aged 18 to 45 years. The study medication was DRSP 4.0mg daily for 24 days followed by a placebo for 4 days (DRSP 4 mg 24/4, Exeltis, Spain) for thirteen 28-day treatment cycles. The primary efficacy endpoint was the overall Pearl Index (PI). Bleeding patterns, changes in vital signs and changes in laboratory values were also analyzed.Results: A total of 713 participants with 7638 DRSP treatment cycles were analyzed. The overall PI was 0.51 (95% confidence interval, 0.1053-1.4922). The proportion of participants with any bleeding decreased from 72.7% in Cycle 1 to 40% in Cycle 6 and 32.1% in Cycle 13. Unscheduled bleeding decreased from 49.1% in Cycle 1 to 27.8% in Cycle 6 and to 22.8% in Cycle 13. Prolonged bleeding was reported by 6.5% during Cycles 2 to 4 decreasing to 4.2% during Cycles 11 to 13. There were no reports of deep vein thrombosis, pulmonary embolism or hyperkalemia. No relevant changes were observed for laboratory parameters, body weight, body mass index, blood pressure or heart rate. Study drug acceptability was considered as "excellent/good" by over 82% of subjects.Conclusion: This new DRSP-only oral contraceptive provides clinical contraceptive efficacy similar to that of the currently marketed Combination estrogen plus progestin Oral Contraceptive, with a good safety profile, and favorable cycle control.Implications: A novel 4-mg DRSP-only pill taken daily for 24 days followed by a placebo for 4 days demonstrated contraceptive efficacy similar to that of currently marketed Combination estrogen plus progestin Oral Contraceptive, with a good safety profile, and favorable cycle control. [ABSTRACT FROM AUTHOR]

Cryogenic memristor-based DC sources offer a promising avenue for in situ biasing of quantum dot arrays. In this study, we present experimental results and discuss the scaling potential for such DC sources. We first demonstrate the operation of a commercial discrete operational amplifier down to ▪ which is used on the DC source prototype. Then, the tunability of the memristor-based DC source is validated by performing several ▪-DC sweeps with a resolution of ▪ at room temperature and at ▪. Additionally, the DC source prototype exhibits a limited output drift of ▪ at ▪. This showcases the potential of memristor-based DC sources for quantum dot biasing. Limitations in power consumption and voltage resolution using discrete components highlight the need for a fully integrated and scalable complementary metal–oxide–semiconductor-based (CMOS-based) approach. To address this, we propose to monolithically co-integrate emerging non-volatile memories (eNVMs) and ▪ CMOS circuitry. Simulations reveal a reduction in power consumption, down to ▪ per DC source and in footprint. This allows for the integration of up to one million eNVM-based DC sources at the ▪ stage of a dilution fridge, paving the way for near term large-scale quantum computing applications. • A memristor-based DC source exhibits output voltage tunability with limited error. • The prototype can be operated at 1.2 K, showcasing its potential for quantum dot biasing. • Integrated CMOS-memristor circuits reduces power consumption and footprint. • The scaled-up concept allows to integrate up to 300,000 DC sources at 4.2K. [ABSTRACT FROM AUTHOR]

Herein, the effect of a 2 nm thin aluminum layer inserted between the ferroelectric layer and the top electrode in a TiN/Hf0.5Zr0.5O2/TiN stack deposited by reactive magnetron sputtering is investigated. The oxidation of the interfacial layer during annealing due to scavenging of the Hf0.5Zr0.5O2 impacts both the ferroelectric properties and the electrical conductivity of the junction. It is shown that the overall conductivity of the junction is boosted 20 folds while the resistance ratio between the positive and negative polarization states is increased from 1.3 up to 3.7. Through a systematic analysis of programming conditions, pulse duration, and height, we show that both the remanent polarization and On/Off current ratio can be enhanced at the expanse of the endurance leading to a trade‐off. [ABSTRACT FROM AUTHOR]

Highlights: [•] Plasma etching of a-Si nanowires over nanotopography in SiO2 is demonstrated. [•] The etch rates dependence on the ICP parameters is investigated. [•] The oxide etch-stop layer changes the C4F8 passivation ratio needed. [•] A low pressure is also necessary to etch the a-Si into the oxide nanotrenches. [•] We argue that these two behaviors could be attributed to surface charging effects. [Copyright &y& Elsevier]

We have investigated ArF ( λ=193 nm) excimer laser-induced crystallization of amorphous CdSe semiconductor thin films. The crystallization has been monitored by a related photoluminescence emission in the free-exciton and defect-band transition regions. For different irradiation conditions, we have observed formation of nanorods, up to 2 μm long, as well as the formation of arrays of CdSe nanobeads with a narrow size distribution and characteristic dimensions corresponding to λ/2 and λ/8. The successful crystallization has also been confirmed by confocal Raman spectroscopy. [ABSTRACT FROM AUTHOR]

Resistive switching (RS) devices are promising forms of non-volatile memory. However, one of the biggest challenges for RS memory applications is the device-to-device (D2D) variability, which is related to the intrinsic stochastic formation and configuration of oxygen vacancy (VO) conductive filaments (CFs). In order to reduce the D2D variability, control over the formation and configuration of oxygen vacancies is paramount. In this study, we report on the Zr doping of TaOx-based RS devices prepared by pulsed-laser deposition as an efficient means of reducing the VO formation energy and increasing the confinement of CFs, thus reducing D2D variability. Our findings were supported by XPS, spectroscopic ellipsometry and electronic transport analysis. Zr-doped films showed increased VO concentration and more localized VOs, due to the interaction with Zr. DC and pulse mode electrical characterization showed that the D2D variability was decreased by a factor of seven, the resistance window was doubled, and a more gradual and monotonic long-term potentiation/depression in pulse switching was achieved in forming-free Zr:TaOx devices, thus displaying promising performance for artificial synapse applications. [ABSTRACT FROM AUTHOR]

The direct control of the tunneling current as a function of electric polarization in ferroelectric tunnel junctions has recently attracted noticeable attention through the availability of the CMOS compatible ferroelectric hafnium zirconium oxide (H f 0.5 Z r 0.5 O 2 ). While a lot of progress has been made in the understanding of ferroelectric tunnel junctions, the control and optimization of the volume fraction of the polar orthorhombic phase are still in its infancy and raise the question whether all observed resistive switching events are necessarily associated with polarization reversal. Trap-assisted tunneling is also able to modulate the current density through a field-induced variation of the oxygen vacancy density across the tunnel junction. The amplitude of the effect should depend on the pre-existing density of oxygen vacancies introduced during the fabrication. Here, by controlling the oxygen partial pressure during the RF magnetron sputtering deposition of the non-polar monoclinic phase of H f 0.5 Z r 0.5 O 2 thin films of approximately 3 nm, we demonstrate tuning of its transport mechanism due to the formation of oxygen vacancies. We show that two mechanisms dominate the current transport depending on the average distance between traps. For large oxygen content in the H f 0.5 Z r 0.5 O 2 thin film, direct tunneling (DT) is the dominant transport mechanism, while the electrical conductivity in the oxide can be described by the phonon-assisted tunneling between traps (PATTs) for the oxygen deficient H f 0.5 Z r 0.5 O 2 thin film. We derive a critical inter-trap distance and a critical thickness value that explains the transition from DT to PATT mechanism in H f 0.5 Z r 0.5 O 2 thin films. [ABSTRACT FROM AUTHOR]

In this article, a flip-chip assembly using a heterogeneous solder bump structure is studied. The metallurgical and shape evolution, from bump fabrication through final assembly, is presented, characterized, and discussed. Aiming for lower residual stress during flip-chip assembly, a sequentially plated bump is fabricated to ensure a ductile low Ag content solder proximate to the fragile chip back end of line (BEOL) layers while providing a separate solder portion with a high Ag content. Such a heterogeneous structure is enabled by the integration of a Ni cap barrier within the sequential electroplating process that serves to prevent Ag diffusion between the two distinct solder portions. The heterogeneous structure is shown to remain intact through the chip join operation, thereby proposing improved BEOL integrity during joint solidification. Further, the cap barrier induces a unique, pillar-like solder structure that provides the opportunity to optimize fine pitch assembly processes without the use of a stiff Cu-pillar layer. Finally, the cap barrier is shown to successfully break down using an additional reflow after underfill reinforcement, thus homogenizing the structure into a high-Ag content solder to optimize electromigration resistance. [ABSTRACT FROM AUTHOR]

High-quality germanium epilayers on Si with low threading-dislocation density were achieved by sintering of porous Ge/Si films. The process consists in the formation of porous Ge nanostructures by dislocation-selective electrochemical etching of Ge/Si films, followed by high-temperature treatment to generate a monocrystalline, voided Ge layer that intercepts dislocations and prevents them from propagating to the sample surface. In this work, we model the morphological changes that occur during the thermal treatment-induced surface diffusion of an axially symmetric hole. Simulations and experiments show individual large spherical voids, aligned along the dislocation core. The creation of voids could facilitate interactions between dislocations, enabling the dislocation network to change its connectivity in a way that facilitates the subsequent annihilation of dislocation segments. This confirms that thermally activated processes such as state diffusion of porous materials provide mechanisms whereby the defects are removed or arranged in configurations of lower energy. This demonstration paves the way to develop a virtual substrate on many other heterostructures for potential applications in integrated photonic and optoelectronic devices. Image, graphical abstract [ABSTRACT FROM AUTHOR]

Non-volatile resistive switching devices are considered as prime candidates for next-generation memory applications operating at room temperature and above, such as resistive random-access memories or brain-inspired in-memory computing. However, their operability in cryogenic conditions remains to be mastered to adopt these devices as building blocks enabling large-scale quantum technologies via quantum–classical electronics co-integration. This study demonstrates multilevel switching at 1.5 K of Al2O3/TiO2-x resistive memory devices fabricated with complementary metal-oxide-semiconducto-compatible processes and materials. The I–V characteristics exhibit a negative differential resistance (NDR) effect due to a Joule-heating-induced metal-insulator transition of the Ti4O7 conductive filament. Carrier transport analysis of all multilevel switching I–V curves show that while the insulating regime follows the space charge limited current (SCLC) model for all resistance states, the conduction in the metallic regime is dominated by SCLC and trap-assisted tunneling for low- and high-resistance states respectively. A non-monotonic conductance evolution is observed in the insulating regime, as opposed to the continuous and gradual conductance increase and decrease obtained in the metallic regime during the multilevel SET and RESET operations. Cryogenic transport analysis coupled to an analytical model accounting for the metal-insulator-transition-induced NDR effects and the resistance states of the device provide new insights on the conductive filament evolution dynamics and resistive switching mechanisms. Our findings suggest that the non-monotonic conductance evolution in the insulating regime is due to the combined effects of longitudinal and radial variations of the Ti4O7 conductive filament during the switching. This behavior results from the interplay between temperature- and field-dependent geometrical and physical characteristics of the filament. [ABSTRACT FROM AUTHOR]

Studies were conducted to validate from a metallurgical point of view whether a lower cost sequential plating approach to SnAg and SnAgCu (SAC) solder bumping is a suitable alternative to the conventional alloy plating process. A range of Ag content corresponding to typical bump applications was explored with respect to Ag diffusion and intermetallic compound (IMC) formation. Variables that can affect such IMC formation were further explored as a function of underbump metallization (UBM) structure and cooling rate during bump solidification. By comparing the results to those previously reported on SnAg-based alloys, it is demonstrated that the proposed sequential plating process produces very similar microstructures and Ag3Sn IMC morphologies, due to the rapid diffusion and distribution of Ag through the liquid Sn. Known means to mitigate the less desirable large Ag3Sn platelets, that is by changing the top UBM layer from Cu to Ni or by employing an ultrarapid cooling rate, are shown to be equally effective for sequential plating. These observations, in conjunction with the simplicity and flexibility of plating multiple single metals, propose adoption of the sequential plating process as a cost-effective and robust Pb-free bumping solution for fine pitch flip-chip packaging. [ABSTRACT FROM AUTHOR]

Resistive switching and transport mechanisms of Al2O3/TiO2−x memristor crosspoint devices have been investigated at cryogenic temperatures down to 1.5 K, for the future development of memristor-based cryogenic electronics. We report successful resistive switching of our devices in the temperature range of 300–1.5 K. The current–voltage curves exhibit negative differential resistance effects between 130 K and 1.5 K, attributed to a metal–insulator transition of the Ti4O7 conductive filament. The resulting highly nonlinear behavior is associated with an ION/IOFF diode ratio of 84 at 1.5 K, paving the way for selector-free cryogenic passive crossbars. Temperature-dependent thermal activation energies related to the conductance at low bias (20 mV) are extracted for memristors in a low resistance state, suggesting hopping-type conduction mechanisms. Finally, the transport mechanism analysis at 1.5 K indicates that for all resistance states, the conduction follows the space-charge limited current model in low fields, whereas trap-assisted tunneling dominates in higher fields. [ABSTRACT FROM AUTHOR]

• Scaling and controlling the synaptic current is indispensable for integrating emerging non-volatile memories (eNVMs) into different grids and design choices of advanced CMOS Technology nodes. • The maximum current scaling down factor depends on the leakage current of the spiking neuron, and the saturation conditions of the current source of the transconductance amplifier. • The fan-in of the 28 nm FD-SOI analog spiking neuron depends on the eNVMs technology, the width and amplitude of input spikes, the firing threshold of the neuron, and the current scaling down factor. • The tunable and versatile current attenuator allows the integration of various eNVMs into 28 nm FD-SOI technology based analog spiking neural networks. In this work we report a study and a co-design methodology of an analog SNN crossbar output circuit designed in a 28 nm FD-SOI technology node that comprises a tunable current attenuator and a leak-integrate and fire neurons that would enable the integration of emerging non-volatile memories (eNVMs) for synaptic arrays based on various technologies including phase change (PCRAM), oxide-based (OxRAM), spin transfer and spin orbit torque magnetic memories (STT, SOT-MRAM). Circuit SPICE simulation results and eNVM experimental data are used to showcase and estimate the neurons fan-in for each type of eNVM considering the technology constraints and design trade-offs that set its limits such as membrane capacitance, supply voltage, leakage, etc. [ABSTRACT FROM AUTHOR]

The intestinal mucosa contributes to frontline gut defenses by forming a barrier (physical and biochemical) and preventing the entry of pathogenic microbes. One innate role of the human colonic epithelium is to secrete cathelicidin, a peptide with broad antimicrobial and immunomodulatory functions. In this study, the effect of cathelicidin in the maintenance of epithelial integrity, Toll-like receptor recognition, bacterial invasion and initiation of inflammatory response against Salmonella typhimurium is investigated in cultured human colonic epithelium. We found exogenous human cathelicidin restores the epithelial integrity in S. typhimurium-infected colonic epithelial (T84) cells by mostly post-translational effects associated with reorganization of zonula occludens (ZO)-1 tight junction proteins. Endogenous cathelicidin prevents S. typhimurium internalization as shown in colonic epithelial cells genetically deficient in the only human cathelicidin, LL-37 (shLL-37). Moreover, supplementation of shLL-37 cells with synthetic LL-37 reduces the grade of S. typhimurium internalization in a dose-dependent manner. Mechanistically, shLL-37 cells have lower gene expression of TLR4 and pro-inflammatory cytokine IL-1β in response to S. typhimurium. Thus, human cathelicidin aids in the early colonic epithelial defenses against enteric S. typhimurium by preventing bacterial invasion and maintaining epithelial barrier integrity, likely to occur due to the production of sensing TLR4 and pro-inflammatory cytokines. [ABSTRACT FROM AUTHOR]

An sFlt-1/PlGF ratio <38 rules out the short-term prediction of PE, whereas ratios >85 and >110 rule in the diagnosis of early- and late-onset PE, respectively [[2]], [[6]]. It is worth noting that the authors found that the Thermo Fisher and Roche ratios were similar in normal pregnancies (median ratio values of 48.04 and 35.29, respectively) but that they were very different in the PE subgroup (median ratio values of 150.12 and 85.44, respectively) [[11]]. [Extracted from the article]

A method of simulating metallic-island single electron transistors (SETs) and small circuits which speeds up the design-fabrication-characterization cycle is proposed. The method combines finite-elements method to extract device capacitance matrix and standard master equations solved by Monte Carlo to simulate device transport characteristics based on the fabrication geometry and materials. It allows simulation of SET circuits. The simulation method is detailed using two capacitively coupled SETs acting either as an electron box or a sensor. The method is also compared with isolated SETs fabricated using the nanodamascene process and characterized at low temperatures. Experimental devices show clear Coulomb blockade diamonds at 1.5 K and charging energies up to 3 meV. The simulation platform predicts the electrical behavior accurately with minimal fitting parameters. This method allows rapid and accurate design iterations before costly fabrication. [ABSTRACT FROM AUTHOR]

In this work we demonstrate the use of Fully Depleted Silicon On Insulator (FDSOI) transistors as pH sensors with a 23 nm silicon nitride sensing layer built in the Back-End-Of-Line (BEOL). The back end process to deposit the sensing layer and fabricate the electrical structures needed for testing is detailed. A series of tests employing different pH buffer solutions has been performed on transistors of different geometries, controlled via the back gate. The main findings show a shift of the drain current (I D ) as a function of the back gate voltage (V B ) when different pH buffer solutions are probed in the range of pH 6 to pH 8. This shift is observed at V B voltages swept from 0 V to 3 V, demonstrating the sensor operation at low voltage. A high sensitivity of up to 250 mV/pH unit (more than 4-fold larger than Nernstian response) is observed on FDSOI MOS transistors of 0.06 µm gate length and 0.08 µm gate width. [ABSTRACT FROM AUTHOR]

Mesoporous germanium (MP-Ge) has been predicted to play an important role in a wide range of potential applications. These porous Ge networks are characterized by physical and chemical properties that contrast with their bulk counterpart. For more than two decades, the methods that were used to synthesize these materials were extremely slow and yield non-uniform layers, which limit their applications. Here we demonstrate the synthesis of thick MP-Ge films with high growth rate (up to 300 nm/min) by using high-current density and high-frequency bipolar electrochemical etching. An optimized nucleation procedure is also reported. It enables a much better lateral homogeneity of the MP-Ge films. Following these results a refined electrochemical Ge etching model is proposed. The model is confirmed by Fourier Transform Infrared Spectroscopy and Cyclic Voltammetry measurements. Reflectivity measurements were also used to demonstrate that the effective refractive index of MP-Ge can be adjusted as a function of layer porosity. It has been reduced down to 1.76 due to the presence of the mesopores. Finally, a basic interferometric porous Ge sensor is demonstrated, a detection sensitivity of 711 nm/RIU was measured upon exposure to glycerol-water solutions. [ABSTRACT FROM AUTHOR]

• TiO 2 thin films were deposited by reactive magnetron sputtering. • Oxygen vacancy concentration was modulated by tuning the oxygen partial pressure. • Oxygen vacancies concentration narrows the optical bandgap of TiO 2 films. Amorphous TiO 2-x thin films were deposited using direct current reactive magnetron sputtering. It was possible to tune the defect concentration by controlling the oxygen flow rate during the deposition process. The operating deposition regime has a significant influence on the properties of the TiO 2-x film. The refractive index was found to decrease with increasing oxygen flow rate, which was essentially related to changes in film density. Besides this, increasing the oxygen vacancy defect concentration induced a slight decrease in the optical bandgap, as well as widening of the defect's Urbach band tails near the conduction band edge. For TiO 2-x films deposited in oxygen-deficient conditions, the decrease in optical bandgap and widening of Urbach tails induced the shift of the Fermi level towards the conduction band, which enhanced the concentration of the charge carriers. [ABSTRACT FROM AUTHOR]

A letter to the editor is presented which examines how anti-angiogenic assay helps fetal extraction decision in a case of a 25-year-old woman suspected with pre-eclampsia condition.

The development of metallic single-electron transistor (SET) depends on the downscaling and the electrical properties of its tunnel junctions (TJs). These TJs should insure high-ON current, low-OFF current, and low capacitance. We propose an engineered TJ based on multidielectric stacking. A number of high- k and low- k materials were considered to optimize the TJ’s characteristics. The optimized TJ is proven to increase the I\mathrm{{\scriptscriptstyle ON}} current and the I\mathrm{{\scriptscriptstyle ON}}/I\mathrm{{\scriptscriptstyle OFF}} ratio in a double-gate SET. Using TiO2 plasma oxidation and Al2O3 atomic layer deposition, an SET proof of concept, with a double layer TJ, was fabricated and characterized. [ABSTRACT FROM AUTHOR]

A reproducible inductively coupled plasma (ICP) etching process using simultaneously SF 6 /C 4 F 8 gases for the fabrication of ultra-shallow Si 3 N 4 nanostructures is presented. The effect of varying etching parameters such as the coil and platen RF power, the chamber pressure, the C 4 F 8 flow rate and the platen temperature on Si 3 N 4 and ZEP etch rates are investigated. The passivation and etching chemistry balance is used to slow down the Si 3 N 4 etch rate to a limit of 6 nm/min. For lower etch rates, the passivation regime is getting dominant and the surface roughness increases. 10 nm deep Si 3 N 4 nanostructures are patterned without inducing any additional roughness on etched surfaces. [ABSTRACT FROM AUTHOR]

Brain-inspired computing and neuromorphic hardware are promising approaches that offer great potential to overcome limitations faced by current computing paradigms based on traditional von-Neumann architecture. In this regard, interest in developing memristor crossbar arrays has increased due to their ability to natively perform in-memory computing and fundamental synaptic operations required for neural network implementation. For optimal efficiency, crossbar-based circuits need to be compatible with fabrication processes and materials of industrial CMOS technologies. Herein, we report a complete CMOS-compatible fabrication process of TiO 2 -based passive memristor crossbars with 700 nm wide electrodes. We show successful bottom electrode fabrication by a damascene process, resulting in an optimised topography and a surface roughness as low as 1.1 nm. DC sweeps and voltage pulse programming yield statistical results related to synaptic-like multilevel switching. Both cycle-to-cycle and device-to-device variability are investigated. Analogue programming of the conductance using sequences of 200 ns voltage pulses suggest that the fabricated memories have a multilevel capacity of at least 3 bits due to the cycle-to-cycle reproducibility. [Display omitted] • Memristor crossbars fabricated using CMOS-compatible processes and materials. • Bottom electrode fabricated with damascene process. • Memristor devices present at least 3 bits multilevel capacity. • Conductance programming using voltage pulses show quasi-linear LTP and LTD. [ABSTRACT FROM AUTHOR]

Brain-inspired computing and neuromorphic hardware are promising approaches that offer great potential to overcome limitations faced by current computing paradigms based on traditional von-Neumann architecture. In this regard, interest in developing memristor crossbar arrays has increased due to their ability to natively perform in-memory computing and fundamental synaptic operations required for neural network implementation. For optimal efficiency, crossbar-based circuits need to be compatible with fabrication processes and materials of industrial CMOS technologies. Herein, we report a complete CMOS-compatible fabrication process of TiO 2 -based passive memristor crossbars with 700 nm wide electrodes. We show successful bottom electrode fabrication by a damascene process, resulting in an optimised topography and a surface roughness as low as 1.1 nm. DC sweeps and voltage pulse programming yield statistical results related to synaptic-like multilevel switching. Both cycle-to-cycle and device-to-device variability are investigated. Analogue programming of the conductance using sequences of 200 ns voltage pulses suggest that the fabricated memories have a multilevel capacity of at least 3 bits due to the cycle-to-cycle reproducibility. [Display omitted] • Memristor crossbars fabricated using CMOS-compatible processes and materials. • Bottom electrode fabricated with damascene process. • Memristor devices present at least 3 bits multilevel capacity. • Conductance programming using voltage pulses show quasi-linear LTP and LTD. [ABSTRACT FROM AUTHOR]

Nitrogen-vacancy (NV) centers in diamond are a promising candidate as a solid state qubit memory for quantum information as they possess very long coherence times even at room temperature. Furthermore, NV centers are very sensitive to their electromagnetic environment and are addressable in the GHz frequency range. Here we review our progress towards the detection of single NV centers for the implementation of fast on demand coupling between NV centers and GHz electromagnetic fields. Precisely, we present efforts towards mapping NV centers with a cathodoluminescence setup. Developing such capability is important for patterning local one-qubit gates for the application of high amplitude electromagnetic fields as a tuning parameter. [ABSTRACT FROM AUTHOR]

Europium-doped lanthanum oxide (5 mol% Eu3+:La2O3) was prepared by calcining europium-doped lanthanum hydroxide (5 mol % Eu3+:La(OH)3) previously synthesized by a simple hydrothermal method. Interestingly, we observed different emission Eu3+ signatures depending on the phase of the host (lanthanum oxide or hydroxide) by cathodoluminescence. Taking into account that lanthanum oxide easily rehydroxylates in air, for the first time, we report the use of cathodoluminiscence as a novel characterization technique to follow the lanthanum oxide rehydroxylation reaction versus time according to different annealing procedures. Additionally, differential mermal-thennogravimetric analysis, infrared spectroscopy, and X-ray diffraction techniques were used to identify the phases formed from the Eu3+:La(OH)3 depending on temperature and to study the evolution of La2O3 to La(OH)3 versus time. The results showed that the higher the temperature and the longer the annealing time, the higher the resistance to rehydroxylation of the Eu3+:La2O3 sample. [ABSTRACT FROM AUTHOR]

Single-electron transistor (SET) circuits can be stacked above the CMOS platform to achieve functional and heterogeneous 3-D integration of nanoelectronic devices. For SET-CMOS hybridization, CMOS technology is essential for I/O, signal restoration, and maintaining compatibility with established technology. In spite of the SET's unparalleled advantages, its low current drive and output voltage when driving CMOS logic makes its use questionable in commercial ICs, specifically at the SET-CMOS interface. In this paper, we contribute to the design, analysis, and simulation of hybrid SET-CMOS circuits exploiting room-temperature operating SET technology. We developed an efficient computer-aided design tool to simulate large-scale SET and hybrid SET-CMOS circuits with conventional device elements. To demonstrate the SET logic driving capability for CMOS with interconnect parasitics, we analytically derived the SET logic parameters for the 22-nm technology node and used them to simulate hybrid SET-CMOS logic. We studied the performance of such hybrid logic circuit in terms of delay and bandwidth and addressed the tradeoffs between fabrication and electrical parameters. Our simulation results demonstrate the SET logic driving capability for CMOS comparable output voltage at gigahertz frequency in a hybrid SET-CMOS architecture. Finally, a comparison between SET and CMOS logic demonstrates that the SET logic outperforms CMOS. [ABSTRACT FROM AUTHOR]

Two compact models for single-electron memory (SEM) are proposed and validated by comparisons with the program SIMON. The approach is based on the master equation method and the orthodox theory. The specific and efficient algorithms for each model are presented. The first model is static and allows directly calculating the final number of electrons on the memory dot. The second model is dynamic, which evaluates every electron tunnel event to assess the stored charge variation and determines the writing or retention times. Both static and dynamic models are written in Verilog-A language and implemented in IC design framework. These SEM models are attractive for circuit simulation to find out the optimal biasing strategy and memory architecture. [ABSTRACT FROM PUBLISHER]

Abstract: We propose an inductively coupled plasma (ICP) process to etch nanometer scale patterns defined by electron beam lithography in ZEP520A. The nanoscale patterns have been successfully transferred in thermal SiO2 using a CF4 based etching chemistry and a resist post-bake after development. Firstly, we show that platen temperature have a significant effect on line edge roughness (LER). We also present the effect of coil and platen RF power and pressure on sidewall angle, oxide to resist selectivity and LER. We demonstrate that 20nm deep trenches with sidewall angles of 86° and LER of less than 1nm can be etched in an ICP system with a platen temperature of −20°C using an electroresist mask. [Copyright &y& Elsevier]

Abstract: Scanning transmission electron microscopy (STEM) was used to image gold nanoparticles on top of and below saline water layers of several micrometers thickness. The smallest gold nanoparticles studied had diameters of 1.4nm and were visible for a liquid thickness of up to 3.3μm. The imaging of gold nanoparticles below several micrometers of liquid was limited by broadening of the electron probe caused by scattering of the electron beam in the liquid. The experimental data corresponded to analytical models of the resolution and of the electron probe broadening as function of the liquid thickness. The results were also compared with Monte Carlo simulations of the STEM imaging on modeled specimens of similar geometry and composition as used for the experiments. Applications of STEM imaging in liquid can be found in cell biology, e.g., to study tagged proteins in whole eukaryotic cells in liquid and in materials science to study the interaction of solid:liquid interfaces at the nanoscale. [ABSTRACT FROM AUTHOR]

Abstract: Single-electron transistor drain current is studied as a function of the temperature. A current conduction model based on the physical properties of the tunnel junctions is proposed to explain the discrepancies observed at high temperature between the experimental data and Monte Carlo simulations. The extension of the model includes a thermionic and a field assisted emission component. A demonstration of this approach is presented for a metallic single-electron transistor characterized up to 430K. [Copyright &y& Elsevier]

Pharmacological modulation of the GABAA receptor has gained increasing attention as a potential treatment for central processes affected in Alzheimer disease (AD), including neuronal survival and cognition. The proteolytic cleavage of the amyloid precursor protein (APP) through the α-secretase pathway decreases in AD, concurrent with cognitive impairment. This APP cleavage occurs within the β-amyloid peptide (Aβ) sequence, precluding formation of amyloidogenic peptides and leading to the release of the soluble N-terminal APP fragment (sAPPα) which is neurotrophic and procognitive. In this study, we show that at nanomolar-low micromolar concentrations, etazolate, a selective GABAA receptor modulator, stimulates sAPPα production in rat cortical neurons and in guinea pig brains. Etazolate (20 nM–2 μM) dose-dependently protected rat cortical neurons against Aβ-induced toxicity. The neuroprotective effects of etazolate were fully blocked by GABAA receptor antagonists indicating that this neuroprotection was due to GABAA receptor signalling. Baclofen, a GABAB receptor agonist failed to inhibit the Aβ-induced neuronal death. Furthermore, both pharmacological α-secretase pathway inhibition and sAPPα immunoneutralization approaches prevented etazolate neuroprotection against Aβ, indicating that etazolate exerts its neuroprotective effect via sAPPα induction. Our findings therefore indicate a relationship between GABAA receptor signalling, the α-secretase pathway and neuroprotection, documenting a new therapeutic approach for AD treatment. [ABSTRACT FROM AUTHOR]

β-Amyloid peptides (Aβ) that form the senile plaques of Alzheimer disease consist mainly of 40- and 42-amino acid (Aβ 40 and Aβ 42) peptides generated from the cleavage of the amyloid precursor protein (APP). Generation of Aβ involves β-secretase and γ-secretase activities and is regulated by membrane trafficking of the proteins involved in A/3 production. Here we describe a new small molecule, EHT 1864, which blocks the Rac1 signaling pathways. In vitro, EHT 1864 blocks Aβ 40 and Aβ 42 production but does not impact sAPPα levels and does not inhibit β-secretase. Rather, EHT 1864 modulates APP processing at the level of γ-secretase to prevent Aβ 40 and Aβ 42 generation. This effect does not result from a direct inhibition of the γ-secretase activity and is specific for APP cleavage, since EHT 1864 does not affect Notch cleavage. In vivo, EHT 1864 significantly reduces Aβ 40 and Aβ 42 levels in guinea pig brains at a threshold that is compatible with delaying plaque accumulation and/or clearing the existing plaque in brain. EHT 1864 is the first derivative of a new chemical series that consists of candidates for inhibiting Aβ formation in the brain of AD patients. Our findings represent the first pharmacological validation of Rac1 signaling as a target for developing novel therapies for Alzheimer disease. [ABSTRACT FROM AUTHOR]

• Hexagonal GeO 2 nanostructures were synthesised cathodically. • Nanorod and nanowire morphologies were obtained. • The electrochemical growth mechanism was considered. • XRD confirmed high crystallinity. • Strong emission of blue and green light was observed. In this paper, hexagonal germanium dioxide (GeO 2) nanostructures with different morphologies and sizes were successfully synthesized by a simple and fast electrodeposition method. We investigated the electrochemical growth mechanism and the structural and optical properties of the products through Fourier transform infrared spectroscopy (FTIR), dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD) and cathodoluminescence (CL). The results reveal that the electrodeposited GeO 2 nanostructures are pure, dense, and highly crystalline. The XRD analyses indicate that the resulting GeO 2 crystals only show peaks related to the α-quartz structure. CL measurements exhibit strong blue and green light emissions related to oxygen vacancies in the core of the GeO 2 crystals. The resulting nanostructures may have potential application in integrated optical devices in the future. [ABSTRACT FROM AUTHOR]

Abstract: We present a bilayer lift-off process without spin coating step, based on evaporated negative ebeam resist QSR-5. This technique is appropriated to process small samples of a few millimetres in size. Evaporated amorphous silicon was used to create the undercut. Patterns were defined by electron beam lithography thanks to the high resolution QSR-5 resist. We optimized the undercut of the a-Si layer using a high density plasma etching system with different recipes to allow submicron lines lift-off. Lift-off with no edge bead effect was performed using this technique. Finally, the process was applied to demonstrate the fabrication of Metal/Semiconductor/Metal (MSM) photodetector on a millimetre scale substrate. [Copyright &y& Elsevier]

Nowadays, there is an increased demand in integrated sensors for electronic devices. Multi-functional sensors provide the same amount of data using fewer sensors. Carbon nanotubes are non-selectively sensitive to temperature, gas and strain. Thus, carbon nanotubes are perfect candidates to design multi-functional sensors. In our study, we are interested in a dual humidity-temperature sensor. Here, we present a novel method to differentiate at least two sources using the sensor's frequency responses based on multiwall carbon nanotubes sensors. The experimental results demonstrate that there are temperature- or moisture-invariant frequencies of the impedance magnitude, and their values depend on the sensor's geometry. The proposed measurement model shows that source-invariant frequencies of the phase can be also determined. In addition, the source separation method is generalized to other materials or sources enabling multi-functional sensors for environment monitoring. [ABSTRACT FROM AUTHOR]