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Objective This case series retrospectively reviewed the outcomes in patients implanted with combined, synchronous dorsal root ganglion stimulation (DRGS) and spinal cord stimulation (SCS) connected to a single implantable pulse generator (IPG) in a tertiary referral neuromodulation centre in the United Kingdom. Methods Twenty-six patients underwent a trial of DRGS+SCS for treating focal neuropathic pain between January 2016 and December 2019, with a follow-up in February 2022. A Transgrade approach was employed for DRGS. Patients were provided with 3 possible stimulation programs: DRGS-only, SCS-only, or DRGS+SCS. Patients were assessed for pain intensity, patients' global impression of change (PGIC), preferred lead(s) and complications. Results Twenty patients were successful and went on for full implantation. The most common diagnosis was Complex Regional Pain Syndrome. After an average of 3.1 years follow-up, 1 patient was lost to follow-up, and 2 were non-responders. Of the remaining 17 patients, 16 (94%) continued to report a PGIC of 7. The average pain intensity at Baseline was 8.5 on an NRS scale of 0–10. At the last follow-up, the average NRS reduction overall was 78.9% with no statistical difference between those preferring DRGS+SCS (n  = 9), SCS-only (n  = 3) and DRGS-only (n  = 5). The combination of DRGS+SCS was preferred by 53% at the last follow-up. There were no serious neurological complications. Conclusions This retrospective case series demonstrates the potential effectiveness of combined DRGS+SCS with sustained analgesia observed at an average follow-up of over 3 years. Implanting combined DRGS+SCS may provide programming flexibility and therapeutic alternatives. [ABSTRACT FROM AUTHOR]

In this study, the corrosion inhibition performance of the natural polysaccharide guar gum (GG) for N80 carbon steel in CO2-saturated saline solution at different temperatures and immersion times was investigated by weight loss and electrochemical measurements. The results have revealed that GG showed good inhibition performance at lower and higher temperatures. The inhibition efficiency observed via weight loss measurements reached 76.16 and 63.19% with 0.4 g L−1 of GG, at 25 and 50 °C, respectively. The inhibition efficiency of GG increased as the inhibitor concentration and immersion time increased but decreased with increasing temperature. EIS measurements have shown that, even after prolonged exposure, GG was still able to protect the metal surface. Potentiodynamic measurements showed the mixed-type nature of GG inhibitive action. The Temkin and Dubinin–Radushkevich adsorption isotherm models give accurate fitting of the estimated data, and the calculated parameters indicated that the adsorption of GG occurred mainly via an electrostatic or physical adsorption process. The associated activation energy (Ea) and the heat of adsorption (Qa) supported the physical adsorption nature of GG. FTIR analysis was used to explain the adsorption interaction between the inhibitor and the N80 carbon steel surface. SEM-EDS and AFM confirmed the adsorption of GG and the formation of an adsorptive layer of GG on the metal surface. [ABSTRACT FROM AUTHOR]

Objective: We performed a systematic review to summarize the knowledge regarding the prevalence of burnout among intensive care unit physicians. Methods: We conducted a systematic review of the MEDLINE and PubMed® databases (last update 04.02.2019) with the goal of summarizing the evidence on burnout among intensive care unit physicians. We included all studies reporting burnout in intensive care unit personnel according to the Maslach Burnout Inventory questionnaire and then screened studies for data on burnout among intensive care unit physician specifically. Results: We found 31 studies describing burnout in intensive care unit staff and including different healthcare profiles. Among these, 5 studies focused on physicians only, and 12 others investigated burnout in mixed intensive care unit personnel but provided separate data on physicians. The prevalence of burnout varied greatly across studies (range 18% - 49%), but several methodological discrepancies, among them cut-off criteria for defining burnout and variability in the Likert scale, precluded a meaningful pooled analysis. Conclusion: The prevalence of burnout syndrome among intensive care unit physicians is relatively high, but significant methodological heterogeneities warrant caution being used in interpreting our results. The lower reported levels of burnout seem higher than those found in studies investigating mixed intensive care unit personnel. There is an urgent need for consensus recommending a consistent use of the Maslach Burnout Inventory test to screen burnout, in order to provide precise figures on burnout in intensive care unit physicians. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, we introduce a simple and well‐defined approach for the design of fast settling amplifiers suitable for switched‐capacitor circuits and characterized by low capacitive loads, in the order of few pico‐farad. In the specific, the design is based on a new Bessel‐like compensation that sets the phase of the closed‐loop amplifier to be linearly related to the frequency, thus emulating the behavior of an ideal delay, like in a Bessel filter. The proposed Bessel‐like approach is validated through the design and the simulation of two 3‐stage amplifiers in a 65‐nm CMOS process. [ABSTRACT FROM AUTHOR]

In this paper, we propose a new approach for the robust design of complementary metal-oxide-semiconductor amplifiers based on settling-time specifications. The approach is based on the definition of the separation factors and on the analysis of their role in the settling time. We define a design strategy for being certain that an OTA satisfies the settling-time constraint under any statistical variation of process or design parameters. The proposed strategy is applied to the transistor level design of a two-stage amplifier and a three-stage one. Simulation results, in good agreement with theory, confirm the validity of the proposed approach. Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The noise of cascode transistors is usually considered to be negligible. It is demonstrated in this paper that this is not the case for an operational transconductance amplifiers exploiting Miller compensation via an embedded current buffer. Analysis, validated through simulations, shows that the noise power spectral density of the cascode transistor implementing the buffer, can be dominant at high frequencies. Its contribution can be of the same order of magnitude as that of the transistors in the first gain stage. A design equation is also given to limit the increase of this output noise contribution. Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

[Display omitted] • Corrosion process of copper NPs/titanium surface in the presence of tryptophan. • Complex investigations: EIS, PDP, AFM, SEM, XPS, Raman, FT-IR, SERS, SEIRA, nano-IR. • Tryptophan triggered formation of Cu-Trp complex and nano-galvanic coupling of CuNPs-Ti. • Conformational changes of Trp (indole ring, amine group) on the corroded CuNPs-Ti surface. A combination of electrochemical and spectroscopic studies allows for understanding and describing the processes that occur on a nano-modified commercial pure Ti by Cu nanoparticles (CuNPs) in the presence and absence of tryptophan (Trp). The electrochemical results confirmed that the deposition of a thin CuNPs layer on the Ti substrate improves the corrosion resistance of the substrate under simulated physiological conditions. The addition of Trp to the corrosive environment accelerated the degradation of the CuNPs coating likely via the formation of a Cu-Trp complex. The degradation of the coating led to the formation of nano-galvanic sites at the substrate/ CuNPs coating interface, which in turn had a detrimental effect on the substrate and further increased the degradation of the coating. The conformational changes of Trp on the corroded CuNPs-Ti surface have been investigated by surface-enhanced vibrational techniques. Trp was adsorbed on the corroded CuNPs-Ti surface through the indole ring, which adopts a more/less horizontal orientation, and the protonated amine group in the presence of chloride and phosphate ions on the metallic surface. The application of a combination of infrared spectroscopy with atomic force microscopy (AFM-IR) proved that Trp covered the bimetal surface and caused the significant degradation of the surface. [ABSTRACT FROM AUTHOR]

Corrosion behaviour of carbon steel (K-55) in fracturing fluid was studied with a rotation cylinder electrode, under static and rotation conditions by means of several electrochemical techniques which are as follows: open circuit potential (OCP) decay, potentiodynamic polarisation and electrochemical impedance spectroscopy (EIS). The corrosion rate was determined by weight loss measurements. The electrode surface after a prefixed immersion time was characterised by scanning electron microscopy (SEM) and X-ray diffraction (XRD). The results indicated that carbon steel showed anodic dissolution behaviour that increased under rotating condition. The cathodic polarisation current density also increased with the electrode rotation due to the increased oxygen diffusion on the electrode surface. Two different oxide layers were formed: a dark, thin layer of magnetite tightly adhering to the electrode surface, characterised by localised corrosion spots, and a porous reddish layer of poorly adhering hematite (FeO) and maghemite (γ-FeO). Under higher rotation rate, the developed oxide layer was not so stable, owing to the shear stress induced between the solution and the specimen surface, enhancing the corrosion rate. [ABSTRACT FROM AUTHOR]

Electrokinetic effects associated with corrosion deposit formation in simulated high temperature primary water have been investigated. A miniature flow cell was designed for the purpose of creating regions of accelerated flow to produce areas of net anodic and cathodic activity which may be characterised by determination of electrode polarisations. Post-test XRD and GDOES examination of so polarised electrodes showed that the rate of oxide deposition and the oxide structure was strongly dependent on the electrochemical corrosion potential. This work underlines the importance of anodic processes generated by streaming potentials which can lead to enhanced oxide deposition. [ABSTRACT FROM AUTHOR]

Protection, conservation, and site-management planning are normally financed and conducted on major archaeological sites only, where there are expectations for visitor access and economic returns. Many smaller sites with lesser visible remains are then virtually abandoned, despite the value of their physical remains and archaeological, historical, and scientific potential. A pilot project by Abu Dhabi Authority for Culture and Heritage (now Abu Dhabi Tourism and Culture Authority) was conducted at Rumeilah, an Iron Age site excavated over the past forty-five years. The project consisted of a full-scale site-management planning process including documentation and assessment of the site conditions and of its administrative context to demonstrate the benefits of applying value and community-based site-management planning processes to ‘invisible’ heritage. The process resulted in the development of a management plan which identifies continued explorations at the site and in the involvement of local schools and universities the activities that will be able to sustain its long-term preservation. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, a novel gate-level strategy for designing Carry-Select adders is proposed. The strategy is more general than the previously proposed techniques, and accounts for the dependence of multiplexer delay on its fan-out. Moreover the strategy is simple and systematic, and is helpful for designing Carry-Select adders with a pencil-and-paper approach. An approximate expression of the minimum delay achievable is derived to estimate performance before carrying out the design. The proposed strategy is validated in more than 1000 adders. Analysis confirms that the strategy leads to a delay which is minimal in most cases, and always within 5.7%. [ABSTRACT FROM AUTHOR]

The present paper addresses an improved low-power high-speed buffer amplifier topology for large-size liquid crystal display applications. The proposed buffer achieves high-speed driving performance while drawing a low quiescent current during static operation. The circuit offers enhanced slewing capabilities with a limited power consumption by exploiting a slew detector which monitors the output voltage of the input differential amplifier and outputs an additional current signal providing slew-rate enhancement at the output stage. Post-layout simulations show that the proposed buffer can drive a 1 nF column line load with 8.5 V/μs slew-rate and 0.8 μs settling time, while drawing only 8 μA static current from a 3 V power supply. [ABSTRACT FROM AUTHOR]

This work proposes and develops an original compensation approach for low-power three-stage operational transconductance amplifiers driving large capacitive loads. The proposed solution is based on the basic reversed nested Miller compensation and exploits a voltage buffer and two nulling resistors in the compensation network, along with a feedforward stage to improve slewing and settling performance. A well-defined design procedure using the loop gain phase margin as the main design parameter is also developed. SPECTRE simulations on a three-stage amplifier are carried out and are found to be in excellent agreement with the theoretical analysis, showing a significant improvement of the proposed approach over traditional compensation strategies in terms of small-signal and large-signal performance. Monte Carlo simulation results finally prove the proposed technique to be well-guarded against process parameter variations. [ABSTRACT FROM AUTHOR]

One consequence of years of dictatorial regime, international embargo and war was isolation of the professional community responsible for the protection of cultural heritage in Iraq. This community was cut off from international debate concerning the development of methodologies and theories on the conservation and management of archaeological sites, historic monuments and districts. The Iraq State Board of Antiquities and Heritage (SBAH), the governmental body responsible for the nation's cultural heritage, was also depleted of resources. Professionals could not access information, new technologies, such as the Internet and digital photography, and could not follow the international literature or discussions reflecting advances in practice. The Getty Conservation Institute and the World Monuments Fund partnered in late 2003 to form the Iraq Cultural Heritage Conservation Initiative (hereafter called the Initiative), to assist the SBAH to redevelop its professional and managerial capabilities. In meetings with the directors of departments of the SBAH in 2004, a plan was conceived to address the problems. A series of training courses was developed aimed at various categories of SBAH's staff, from directors of regional offices to archaeologists, engineers and surveyors. The training programmes covered technical topics such as the use of computers, geographic information systems (GIS), satellite imagery, digital photography, survey equipment (with equipment purchased by the Initiative and organisations such as UNESCO), and other issues related to the documentation, assessment of condition, and management of cultural heritage sites. A parallel activity is developing a GIS for the SBAH to maintain a national inventory of the archaeological and historic sites and monuments of Iraq — a tool that will also enable SBAH to record damage and threats to sites and to plan protective and conservation interventions. Due to the security situation in Iraq, development of the GIS has been reconfigured to be web-based since locating it in Baghdad was not practicable. The web-based GIS, dubbed MEGA (Middle East Geodatabase for Antiquities) has first been developed for Jordan given ready access to the country. The Jordanian Department of Antiquities (DOA) has been of great assistance in mounting training activities for Iraqi colleagues and has opened sites in Jordan for field exercises. This paper illustrates the activities of the Initiative and advocates similar projects not only in post-conflict areas, but as a matter of standard practice generally, since trained personnel and inventories can reduce the damage that war and civil strife so often inflict on cultural heritage. [ABSTRACT FROM AUTHOR]

The corrosion behavior of two silicon steels with the same chemical composition but different grains sizes (i.e., average grain area of 115.6 and 4265.9 µm2) was investigated by metallographic microscope, gravimetric, electrochemical and surface analysis techniques. The gravimetric and electrochemical results showed that the corrosion rate increased with decreasing the grain size. The scanning electron microscopy/energy dispersive x-ray spectroscopy and X-ray photoelectron spectroscopyanalyses revealed formation of a more homogeneous and compact corrosion product layer on the coarse-grained steel compared to fine-grained material. The Volta potential analysis, carried out on both steels, revealed formation of micro-galvanic sites at the grain boundaries and triple junctions. The results indicated that the decrease in corrosion resistance in the fine-grained steel could be attributed to the higher density of grain boundaries (e.g., a higher number of active sites and defects) brought by the refinement. The higher density of active sites at grain boundaries promote the metal dissolution of the and decreased the stability of the corrosion product layerformed on the metal surface. [ABSTRACT FROM AUTHOR]

The following paper has been conceived to deal with the contents of some lectures aimed at enhancing courses on digital electronic, microelectronic or VLSI systems. Those lectures show how to use a hardware description language (HDL), such as the VHDL, to specify, design and verify a custom microprocessor. The general goal of this work is to teach how to handle the design of a complete digital system, using a commercially important HDL, from specification to testing. From a pedagogical point of view, this is very important since it helps students get used to a design flow commonly accomplished within semiconductors and microelectronics industries. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, four different driver circuits for an active matrix organic light-emitting diode (AMOLED) pixel based on thin film transistor (TFT) technology are analyzed and compared. In particular, the comparison analyzed accuracy, driving speed, power consumption and area occupied. Moreover, in order to allow array simulations, the RC equivalent models of the pixel were also derived. The results were achieved considering a QVGA display (320×240), a line frequency of 60Hz, and were verified by simulations with AIM-SPICE. [Copyright &y& Elsevier]

In this paper, an innovative active-quenching and recharging circuit for single-photon avalanche diodes is presented. The proposed driver is very fast and extremely compact. It is based on a novel quenching paradigm that heavily reduces dead time, which now is only limited by the sensor rather than the circuit itself. To test speed performance, we designed the circuit with a dielectrically insulated 2-μm technology supplied by ST Microelectronics and carried out postlayout simulations using SPECTRE. Moreover, the functionality of the circuit was also validated with experimental measurements on a medium scale integration (MSI) discrete implementation. [ABSTRACT FROM AUTHOR]

Abstract: A fast active quenching and recharging circuit (AQRC) for single-photon avalanche diodes (SPAD) is presented in this paper. The proposed driver exhibits a lower than 10ns overall quenching time allowing a tunable excess voltage from 5 to 12V. The circuit was designed by using the dielectrically insulated BiCMOS technology supplied by ST Microelectronics. Many post-layout ELDO simulations have validated the high performance of the proposed topology, which is actually the fastest AQRC reported in the literature. [Copyright &y& Elsevier]

Considers different types of actions that have caused damage to Iraq's heritage following the war in 2003, evaluating the impact each has had. Causes of many of the problems affecting post-war reconstruction in Iraq; Ways by which cultural heritage of Iraq has been destroyed during the years of the Ba'athist regime of former Iraqi President Saddam Hussein; Accusations against the U.S. Army in reports in the Arab media; Action that has provoked international censure against the coalition forces; Types of looting occurred in the aftermath of the war.

In this brief, a new method for analytically evaluating the harmonic distortion (HD) in class-AB stages is introduced. It is based on modeling each push-pull device in the stage with a different third-order polynomial. The coefficients of these polynomials are then evaluated by straightforward computations or by pencil-and-paper analysis on the transcharacteristic of the stage. The resulting theory was validated by simulations and is able to predict the HD behavior of a class-AB stage over a wide range of input values. An example of the use of the theory for pencil-and-paper analysis is also given. [ABSTRACT FROM AUTHOR]

Discusses design guidelines for reversed nested Miller compensation in three-stage amplifiers. CMOS implementation; Right-half-plane (RHP) zero cancellation with resistors; RHP-zero cancellation with voltage follower.

Proposes a strategy for the design of source-coupled logic gates both with and without an output buffer. Simplicity of the design criteria; Derivation of closed-form design equations to size bias currents and transistor aspect ratios; Avoidance of simulation iterations.

Describes a complementary metal oxide semiconductor low-voltage positive current conveyor of second generation. Fabrication of a prototype in a 0.35-micrometer technology; Characteristics of the circuit; Attainment of good frequency performance.

Presents models which evaluate the propagation delay of a resistance-capacitance chain driven by a step input current generator. Development of different approximations; Optimization of the propagation delay when inserting repeaters in a chain of transmission gates; Validation of results by Spice simulation using a complementary metal oxide semiconductor technology.

Proposes an approach for the evaluation of high-frequency harmonic-distortion factors in feedback amplifier systems. Improvement in the comprehension of harmonic-distortion generation; Impact of the frequency compensation on linearly performance; Details on the frequency range of interests.

Analyzes the power-supply noise attenuation (PSNA) in bandgap voltage references. Description of the frequency behavior of the PSNA; Illustration of the circuits being analyzed; Distinction between the bandgap voltage references.

Compares the adiabatic and conventional complementary metal oxide semiconductors NAND/NOR gates at the gate level versus the fan-in. Energy consumption of adiabatic and conventional gates; Energy-delay product comparison; Equivalent resistance of the transmission gate.

Reviews the nested Miller compensation of multi-stage amplifiers by using a simple design-oriented approach. Compensation networks with nulling resistors; Use of nulling resistors to eliminate right-half-pipe zeros; Component values for different zero-canceling approaches.

Presents information on a study which discussed design guidelines for complementary metal-oxide semiconductor current amplifiers with a high-drive capability. Features of current operational amplifiers (COA); Distinction between COA and voltage-feedback COA; Configurations for the input stages and output stages of COA; Conclusions.

Deals with a study which compared buffer and NAND-NOR adiabatic gates to a gate designed with the traditional complementary metal-oxide-semiconductor approach. Introduction to the principle of adiabatic switching; Comparison of NAND-NOR gates; Discussion on the partially adiabatic technique 2N-2P in terms of power consumption.

Deals with a study which presented an equivalent resistor-capacitor to model the dynamic behavior of a charge pump which takes into account the parasitic capacitances. Equivalent model; Model validation; Conclusion.

Presents information on a study which proposed a pencil-and-paper optimized design for current mode logic (CML) and emitter coupled logic (ECL) gates. CML and ECL propagation delays; Optimized design of CML; Comparison between CML and ECL; Conclusions.

Describes some design aspects in the implementation of complementary metal oxide semiconductor (CMOS) current comparators. Discussion on techniques for offset and charge-injection compensation; Sensitivity and switching time of this comparator design.

This paper presents a systematic analytical comparison of the single‐Miller capacitor frequency compensation techniques suitable for three‐stage complementary metal–oxide–semiconductor (CMOS) operational transconductance amplifiers (OTAs). The comparison is carried out with the aid of a figure of merit that expresses a trade‐off among gain‐bandwidth product, load capacitance, and total transconductance, for equal values of the phase margin. The results found can be used before the transistor‐level design step and provide useful guidelines for the optimization of the small‐signal performance. Simulations by using a 65‐nm standard CMOS technology confirming the effectiveness of the theoretical comparison for 10 different OTA topologies are also provided. [ABSTRACT FROM AUTHOR]

In this paper, we provide a new procedure that allows to design a generic three-stage amplifier from settling-time specifications. The procedure analyze the settling-time of pure two- or three-pole amplifiers (i.e., with no zeros) and extends the results to a generic amplifier that includes one or two zeros even placed in the right-half plane. The validity of the proposed approach is demonstrated through a design example of a three-stage CMOS amplifier suitable for switched-capacitor applications. [ABSTRACT FROM AUTHOR]

The effect of CO2 partial pressure on the corrosion inhibition efficiency of gum arabic (GA) on the N80 carbon steel pipeline in a CO2-water saline environment was studied by using gravimetric and electrochemical measurements at different CO2 partial pressures (e.g., P CO 2 = 1, 20 and 40 bar) and temperatures (e.g., 25 and 60 °C). The results showed that the inhibitor efficiency increased with an increase in inhibitor concentration and CO2 partial pressure. The corrosion inhibition efficiency was found to be 84.53% and 75.41% after 24 and 168 h of immersion at P CO 2 = 40 bar, respectively. The surface was further evaluated by scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), grazing incidence X-ray diffraction (GIXRD), and X-ray photoelectron spectroscopy (XPS) measurements. The SEM-EDS and GIXRD measurements reveal that the surface of the metal was found to be strongly affected by the presence of the inhibitor and CO2 partial pressure. In the presence of GA, the protective layer on the metal surface becomes more compact with increasing the CO2 partial pressure. The XPS measurements provided direct evidence of the adsorption of GA molecules on the carbon steel surface and corroborated the gravimetric results. [ABSTRACT FROM AUTHOR]

Inverting and noninverting class-AB output stages suitable for low-voltage nanometer CMOS technologies are presented, analyzed in detail and main design criteria highlighted. The solutions are based on a previous topology that is now modified and improved by avoiding both the use of floating voltage sources and the need for extensive accurate matching. As an example of application, the proposed inverting output stage is exploited in a three-stage amplifier designed in a standard 65-nm CMOS process and supplied from 1 V. Simulations show that the solution provides very good output current drive capability and current efficiency, as it is capable to source/sink a maximum output current of 1.5 mA from a quiescent value of 20 μA. Besides, it allows easy frequency compensation with very good settling performance and linearity. [ABSTRACT FROM AUTHOR]

Guar gum (GG) was investigated as a possible eco-friendly corrosion inhibitor for pure aluminium in a 1-M HCl solution at different temperatures and immersion times using gravimetric and electrochemical techniques. The results showed that GG was a good corrosion inhibitor for pure aluminium in the studied environment. The inhibition efficiency of GG increased with increasing inhibitor concentration and immersion time but decreased with increasing temperature. Polarisation measurements revealed that GG was a mixed type inhibitor with a higher influence on the cathodic reaction. The adsorption behaviour of the investigated inhibitor was found to obey the Temkin adsorption isotherm and the calculated values of the standard free adsorption energy indicate mixed-type adsorption, with the physical adsorption being more dominant. The associated activation energy (Ea) and the heat of adsorption (Qa) supported the physical adsorption nature of the inhibitor. Fourier-transform infrared spectroscopy (FTIR) and Raman/SERS were used to explain the adsorption interaction between the inhibitor with the surface of the metal. The results suggested that most inhibition action of GG is due to its adsorption of the metal surface via H-bond formation. [ABSTRACT FROM AUTHOR]