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Introduction. Static converters are among the most widely used equipment in several applications, for example, electric power transmission, motor speed variation, photovoltaic panels, which constitute the electronic components. The design of a power electronics device is done without any real means of predicting electromagnetic disturbances during the product development phase. This case-by-case development process is repeated until a solution is found that best respects all the electromagnetic compatibility constraints. The purpose is the development of a boost-inverter converter under electromagnetic compatibility constraints. The improvements made to the inverter are mainly in the control, the choice of power switches and the electromagnetic compatibility solutions brought to the device. The quality of the wave is improved by acting on the type of control and the choice of switches. Methods. In the first time, we have highlighted a comparison between two most frequently used power components (MOSFET and IGBT) in the inverter and the boost by simulation using ISIS and LT-spice softwares. The sinusoidal voltage with modulation circuit is greatly simplified by the use of the PIC16F876A microcontroller. In a second step, we validate the obtained results with experimental measurements. We start with the boost, then the inverter. In addition, the circuits made are housed in boxes to avoid accidental contact for people. The equipment is designed to isolate the load from the power supply in case of: over voltages, under voltages, high and low battery level and short circuits. Results. All the simulations were performed using the ISIS and LT-spice softwares. The obtained results are validated by experimental measurements performed in the ICEPS Laboratory at the University of Sidi Bel-Abbes in Algeria. The realization of a single-phase inverter with a pulse width modulation control, associated with a boost chopper and the waveforms of the current and voltage across each static converter its opening are presented. The sources of disturbances in power devices are at the origin of the temporal and frequency characteristics of the signals coming from the hot spots of the power switches and the resonances created during the switching of these elements.

Introduction. Power electronics devices are among the most widely used equipment in all fields. The increasing performance of these devices makes their electromagnetic interference factor very important. On the other hand, electromagnetic compatibility research is more and more interested in studies on the sources of electromagnetic disturbances, their propagation paths and the methods of reducing these electromagnetic disturbances. The purpose is to study the behavior of the various active power components at high frequency as well as the evaluation of their electromagnetic noise by using simulation and experimental measurement. Methods. In first time, the simulation was realized with the Lt-spice software which presents many advantages in its use and we validate in the second time the results obtained with experimental measurements. We start by study of the behavior of the diode, then the behavior of MOSFET transistor and finally the study of the behavior of the IGBT transistor. Results. All the simulations were performed using the Lt-spice software and the results obtained are validated by experimental measurements performed in the APELEC Laboratory at the University of Sidi Bel-Abbes in Algeria. The waveforms of the current and voltage across each component during its opening are presented. The results of the simulations are compared and validated with the realized measurements in order to better present the influence of the fast switching of semiconductors on the electrical quantities, which causes electromagnetic disturbances in the interconnected electrical system.

Introduction. An electronic control and closing control at the switch (MOSFET) will allow a parallel connection of two DC/DC boost converters. The reason for paralleling converters is to increase the efficiency of the power conversion process. This means that the overall power loss on the main switches is half the power loss on the main switch of a converter. It has been proven that DC-DC converters operating in parallel have different dynamics than a single converter. In this paper, the study is based on a system of two boost converters operating in parallel under current mode control. Although two converters operating in parallel increase the efficiency of the system, if the control parameters are not chosen correctly, the system becomes unstable and starts to oscillate. Purpose of this work is to present the analysis of high frequency electromagnetic disturbances caused by the switching of power switches in DC/DC boost static converters mounted in parallel in the presence of cables. We will study the improvement of the electromagnetic compatibility performances which can be brought by the choice of a static converters for industrial use. Methods. For the study of the path of the currents in common mode and in differential mode, it was possible to evaluate experimentally the electromagnetic compatibility impact in common mode and in differential mode of two boost converters connected in parallel in an electric circuit in connection with the source through a printed circuit board of connection between the source and the load, while using the two basic methods, namely the prediction of the conducted electromagnetic interference, the temporal simulation and the frequency simulation. Results. All the obtained results are validated by experimental measurements carried out at the Djillali Liabes University Sidi-Bel-Abbes in Laboratory of Applications of Plasma, Electrostatics and Electromagnetic Compatibility (APELEC). The experimental results obtained in common mode and in differential mode at low, medium and high frequencies are compared between the parallel boost test with and without electromagnetic compatibility filter.

Introduction. Rectifiers are the most important converters in a very wide field: the transport of electrical energy in direct current and in the applications of direct current motors. In most electrical and electronic systems, rectifiers are non-linear loads made up of diodes, therefore they are a source of harmonic pollution at a base frequency with a distorting line current signal that generates electromagnetic interference. There are two disturbance modes: common mode and differential mode. These disturbances caused by the rapid variation of current and voltage as a function of time due to the switching of active components, passive components such as inductors, capacitors, coupling, etc. The purpose of this work is to study the conducted emissions generated by a rectifier connected to the Line Impedance Stabilizing Network in an electric circuit. The determination of these disturbances is done for firstly both common and differential modes at high frequency, and secondly harmonics current, line current at low frequency. The novelty of the proposed work consists in presenting a study of disturbance generated by rectifiers using simulation and also experimental measurements at low and high frequencies in order to compare the results. Methods. For the study of the disturbances conducted by the diode bridge converter (rectifier), the sources of conducted electromagnetic disturbances were presented in the first time. Then, the common and differential modes were defined. This converter was studied by LTspice Software for simulation and also experimental measurements at low frequency for harmonics current and high frequencies for disturbances in common and differential modes. Results. All the simulations were performed using the LTspice software and the results obtained are validated by experimental measurements performed in the APELEC laboratory at the University of Sidi Bel-Abbes in Algeria. The obtained results of conducted emissions at high frequency and total harmonics distortion of current at low frequency are compared between simulation and experiment.

Myeloid sarcoma (MS) is a tumor mass of myeloblasts or immature myeloid cells occurring in an extramedullary site or in the bone and generally precedes or reveals myeloid leukemia. It rarely occurs in the mediastinum. Clinical diagnosis and histology is generally difficult, the treatment is based on chemotherapy-type acute myeloid leukemia. We report the case of a patient diagnosed with anterior mediastinal myeloid sarcoma that revealed acute myeloid leukemia.

Popliteal artery entrapment syndrome (PAES) is where the popliteal artery is compressed-typically by the medial head of the gastrocnemius muscle. PAES is typically treated surgically with popliteal artery release with or without bypass. Graft stenosis is a recognised complication of vein grafts. These are normally treated endovascularly. Endarterectomy of venous graft stenosis may be a useful tool in selected cases, where an endovascular approach was unsuccessful. Long-term follow-up of graft stenosis endarterectomy will allow us to determine effectiveness of this method of treatment where other options have failed., Competing Interests: Competing interests: None declared., (© BMJ Publishing Group Limited 2023. No commercial re-use. See rights and permissions. Published by BMJ.)

Septoria tritici blotch (STB) is a major disease problem of wheat worldwide. To optimize the introgression of resistance genes in elite genotypes throughout traditional or molecular breeding programs, a full understanding of the quantitative inheritance of resistance to Zymoseptoria tritici , plant height (PH), and thousand kernel weight (TKW) is needed. In this study, maternal and cytoplasmic effects of resistance to STB were investigated using P1 (susceptible, high-yielding line) and P2 (resistant, low-yielding line) durum wheat lines and their F 1 , RF 1 , F 2 , RF 2 , BC 1 , RBC 1 , BC 2 , and RBC 2 progeny, assessed for resistance to STB during three growing seasons. Duncan mean's analysis revealed significant differences between generation means for STB, PH, and TKW. The two parents had an extreme pattern. The F 1 and RF 1 segregated close to their respective parents, suggesting the presence of cytoplasmic and maternal genetic effects for Z. tritici resistance, PH, and TKW. Separate generation mean's analysis confirmed the results of the Duncan test. A three-parameter model was found to be not adequate for all traits in all three growing years; while a digenic epistatic model with cytoplasmic or/and maternal effect was adequate for all cases. Narrow-sense heritability was in the range of 50-60%, 30-69%, and 28-31% for STB, PH, and TKW, respectively. For STB, high heritability and the presence of fixable epistatic effect is encouraging and could lead to creating varieties with the right female parent to exploit cytoplasmic and maternal effects in order to improve resistance to Z. tritici in durum wheat., Competing Interests: The authors declare no conflict of interest., (Copyright © 2022 Marwa Hassine et al.)

Aim: The diabetic foot attack (DFA) is perhaps the most devastating form of diabetic foot infection, presenting with rapidly progressive skin and tissue necrosis, threatening both limb and life. However, clinical outcome data in this specific group of patients are not available., Methods: Analysis of 106 consecutive patients who underwent emergency hospitalisation for DFA (TEXAS Grade 3B or 3D and Infectious Diseases Society of America (IDSA) Class 4 criteria). Outcomes evaluated were: 1) Healing 2) major amputation 3) death 4) not healed. The first outcome reached in one of these four categories over the follow-up period (18.4±3.6 months) was considered. We also estimated amputation free survival., Results: Overall, 57.5% (n=61) healed, 5.6% (n=6) underwent major amputation, 23.5% (n=25) died without healing and 13.2% (n=14) were alive without healing. Predictive factors associated with outcomes were: Healing (age<60, p=0.0017; no Peripheral arterial disease (PAD) p= 0.002; not on dialysis p=0.006); major amputation (CRP>100 mg/L, p=0.001; gram+ve organisms, p=0.0013; dialysis, p= 0.001), and for death (age>60, p= 0.0001; gram+ve organisms p=0.004; presence of PAD, p=0.0032; CRP, p=0.034). The major amputation free survival was 71% during the first 12 months from admission, however it had reduced to 55.4% by the end of the follow-up period., Conclusions: In a unique population of hospitalised individuals with DFA, we report excellent healing and limb salvage rates using a dedicated protocol in a multidisciplinary setting. An additional novel finding was the concerning observation that such an admission was associated with high 18-month mortality, almost all of which was after discharge from hospital., Competing Interests: All the authors confirm that they do not have a conflict of interest to report in regard to the manuscript., (Thieme. All rights reserved.)

Whether deep swab cultures taken at admission reliably identify pathogens compared to surgical bone specimens in hospitalized individuals with diabetic foot osteomyelitis and soft tissue infection is unclear. Comparison of microbiological isolates between a deep wound swab (DWS) taken at the time of admission through the actively infected, discharging ulcer probing to the bone and the subsequent surgical bone sample (SBS) taken during surgical debridement was made. A total of 63 subjects (age 60.8 ± 13.5 years, 75% male, 80% Type 2 diabetes, HbA1C 8.9%±2.2%) were included. The proportion of Gram-positive (DWS 49% v SBS 52%) and Gram-negative (DWS 60% v SBS 60%) isolates was similar between the techniques. However, the overall concordance of isolates between the two techniques was only fair (κ=0.302). The best concordance was observed for Staphylococcus aureus (κ=0.571) and MRSA (κ=0.644). There was a correlation between number of isolates in SBS with prior antibiotic therapy of any duration (r= -0.358, p=0.005) and with the duration of ulceration (r=0.296, p=0.045); no clinical correlations were found for DWS. Prior antibiotic therapy (p=0.03) and duration of ulceration <8 weeks (p=0.025) were predictive of negative growth on SBS. In conclusion, we found only a fair concordance between deep wound swabs acquired at admission and surgical bone specimens in those presenting with a severe diabetic foot infection and features of osteomyelitis. Ensuring early surgical debridement of all infected tissue and obtaining bone specimens should be considered a clinical priority, which may also reduce the likelihood of negative growth on SBS.

Lower extremity amputations and diabetic foot-related complications in the Caribbean population have been previously reported. However, there is a lack of evidence that assess the quality of life experienced in such amputees. This study aimed to determine the health-related quality of life (HRQoL) in patients after a major lower limb amputation. Data collection was performed for all major lower limb amputations undertaken at a tertiary care institution in Trinidad and Tobago, between January 2012 to December 2016. The quality of life for patients who were accessible, alive, and willing to participate was assessed using the EuroQol 5D-5L tool. Statistical analysis was performed using the Mann-Whitney U and Kruskal-Wallis tests comparing medians across various subgroups. A total of 134 individuals were still alive and willing to participate in the study. The average EQ-5D-5L index value for the cohort was (0.598), which was significantly lower compared to EQ-5D-5L population norms for Trinidad and Tobago p < 0.05. Statistically significant differences were also seen in median EQ-5D-5L index value for patients who ambulated with a prosthesis (0.787) compared to those who used another device for mobilization (0.656), p < 0.05, and to those patients who did not ambulate (0.195), p < 0.05. A comparable Quality of life was seen between the level of amputation (transtibial versus transfemoral) and gender (males versus females), p-values were 0.21 and 1.0, respectively. Overall quality of life after major amputation, as well as independent mobilization with a prosthesis, continues to be problematic in the Caribbean population. Factors adversely related to the quality of life post major amputation include increasing age, problems related to mobility, and non-ambulatory patients., Competing Interests: A preliminary version of this manuscript was made available Research square as a preprint on August 11th 2020 and assigned a DOI 10.21203/rs.3.rs-54128/v1. However, the manuscript nor its contents have not been previously published., (Copyright © 2021, Pran et al.)

The peroneal artery (PeA) is often a vital target vessel for lower limb revascularization. Exploring the distal PeA can be challenging via the conventional approaches. We present a new, minimally invasive technique for a latero-anterior approach to the terminal PeA without fibular resection as either a target outflow vessel for open bypass revascularization surgery or, as in this report, the inflow for a crural-pedal bypass in a challenging case of critical limb-threatening ischemia., (Crown Copyright © 2020. Published by Elsevier Inc. All rights reserved.)

Objective: The aim was to assess the prognostic impact of perfusion assessments including ankle-brachial Index (ABI) and toe-brachial Index (TBI) on survival of patients who present with diabetic foot ulceration and to analyse clinical outcomes when patients are categorised into three levels of limb ischaemia., Method: This was a retrospective cohort analysis of consecutive patients presenting with foot ulceration. Patients continued with their standard of care, after having baseline assessments of limb perfusion. Patients were retrospectively categorised into three groups according to baseline ABI and TBI: Group 1 (n=31) non-ischaemic (TBI≥0.75, ABI≥0.9), Group 2 (n=67) isolated low TBI with foot ischaemia (TBI<0.75, ABI≥0.90) and Group 3 (n=30) foot-leg ischaemia (TBI<0.75, ABI<0.90)., Results: A total of 128 patients took part in the study. Low TBI was associated with a significant decrease in patient survival (42±20 versus 51±16 months, p=0.011). There was a progressive and significant decline in mean patient survival time (51±16 versus 44±20 versus 39±22 months, respectively, for ANOVA across the three groups, p=0.04). Patients with isolated low TBI had angioplasty and bypass at a rate similar to that of patients in Group 3 (low ABI and low TBI). The proportion of angioplasties was significantly higher in the isolated low TBI (19.4% (13/67) versus the non-ischaemic 3.2% (1/31), p=0.033). Such revascularisation resulted in ulcer healing within the foot ischaemic group that was similar to the non-ischaemic group (68% versus 60% over 12 months, p=0.454)., Conclusion: Regardless of ABI level, measurement of TBI identifies patients with isolated low TBI who require specialised care pathways and revascularisation to achieve ulcer healing that is similar to non-ischaemic patients.

The use of doubled haploid lines improves the efficiency of cultivar development and homozygous genotypes can be obtained in one generation, as opposed to conventional line production, which requires several cycles of self-pollination. However, in durum wheat (Triticum turgidum subsp. durum Desf.), the low efficiency of green plant regeneration and the very high frequency of albino plants hinder the application of this technique.We observed the success of using gynogenesis for durum wheat and the significant influence of growing conditions on ovary and callus development, and on plant regeneration. Our results suggested that the cold pretreatment for 2 weeks is efficient for durum wheat. Furthermore, the addition of 2,4-D, vitamins and glutamine, and the use of maltose as sugar source in media improved the ovary regeneration. We describe in this work an efficient method to regenerate green plants from in vitro durum wheat gynogenesis ., (© 2021. Springer Science+Business Media, LLC, part of Springer Nature.)

Agriculture has new challenges against the climate change: the preservation of genetic resources and the rapid creation of new varieties better adapted to abiotic stress, specially salinity. In this context, the agronomic performance of 25 durum wheat ( Triticum turgidum subsp. durum Desf.) genotypes (nineteen landraces and six improved varieties), cultivated in two semi-arid regions in the center area of Tunisia, were assessed. These sites (Echbika, 2.2 g l -1 ; Barrouta, 4.2 g l -1 ) differ by their degree of salinity of the water irrigation. The results showed that most of the agronomic traits (e.g. spike per meter square, thousand kernels weight and grain yield) were reduced by salinity. Durum wheat landraces, Mahmoudi and Hmira, and improved varieties, Maali and Om Rabia showed the widest adaptability to different quality of irrigation water. Genotypes including Jneh Kotifa and Arbi were estimated as stable genotypes under adverse conditions. Thereafter, salt-tolerant (Hmira and Jneh Khotifa) and the most cultivated high-yielding (Karim, Razzak and Khiar) genotypes were tested for their gynogenetic ability to obtain haploids and doubled haploid lines. Genotypes with good induction capacity had not necessarily a good capacity of regeneration of haploid plantlets. In our conditions, Hmira and Khiar exhibited the best gynogenetic ability (3.1% and 2.9% of haploid plantlets, respectively).

We report a novel application of balloon angioplasty to recanalise a chronically occluded remote endarterectomy superficial femoral artery. This patient previously had two occluded surgical bypass grafts in an attempt to revascularise the limb and presented with critical limb ischaemia and necrotic foot ulcerations. Following the angioplasty, the patient showed significant improvement in rest pain and healing of the ulcerations. This technique may be useful for limb salvage in patients where surgical options have been exhausted.

Carotid endarterectomy (CEA) remains the "gold standard" for atherosclerotic lesions involving the carotid bifurcation. Carotid bypass grafting using either polytetrafluoroethylene or long saphenous vein is a suitable alternative technique, especially in challenging endarterectomy and on-table failed CEA. We report our initial experience of using the Gore Hybrid Vascular Graft (W. L. Gore & Associates, Flagstaff, Ariz) in six patients as a rescue technique when standard CEA failed., (Copyright © 2016 Society for Vascular Surgery. Published by Elsevier Inc. All rights reserved.)

This is a unique case report describing complex limb salvage in a patient who experienced acute limb ischaemia due to a complication of intra-aortic balloon pump (IABP) counterpulsation. This case focuses on a patient who had an IABP counterpulsation device inserted following myocardial infarction, requiring urgent coronary artery bypass grafting for acute coronary syndrome. Postoperatively, the IABP could not be removed, with consequent iliac thrombosis and acute limb ischaemia. Emergency femoral-to-femoral crossover bypass was performed using a polytetrafluoroethylene graft. A portion of the IABP balloon tip was entrapped and retained, however, and became the focus of delayed septicaemia, resulting in graft infection and wound breakdown 6 weeks later. Explantation of the residual balloon tip, ligation of the right external iliac artery and redo femoral-femoral crossover using the great saphenous vein were successfully performed., (2016 BMJ Publishing Group Ltd.)

Objective: This study evaluated the effect of pedal arch quality on the amputation-free survival and patency rates of distal bypass grafts and its direct impact on the rate of healing and time to healing of tissue loss after direct angiosome revascularization in patients with critical limb ischemia (CLI)., Methods: Between 2004 and 2011, patients undergoing distal bypass for CLI (Rutherford 4-6) were divided in groups taking into consideration the state of the pedal arch and direct angiosome revascularization (DAR) and non-DAR. Angiography was used to divide the pedal arch into three groups: complete pedal arch (CPA), incomplete pedal arch (IPA), and no pedal arch (NPA). The primary end points were patency rates at 12 months, amputation-free survival at 48 months, and the rate of healing and time to healing of foot tissue loss., Results: A total of 154 patients (75% men) with CLI underwent 167 infrapopliteal bypasses. Patients were a median age of 75 years (range, 46-96 years). Diabetic mellitus was present in 76%, chronic renal failure in 28%, and ischemic heart disease in 44%. The primary patency rates at 1 year in the CPA, IPA, and NPA groups were 58.4%, 54.6%, and 63.8%, respectively (P = .5168), the secondary patency rates were 86.0%, 84.7%, and 88.8%, respectively (P = .8940), and the amputation-free survival at 48 months was 67.2%, 69.7%, and 45.9%, respectively (P = .3883). Tissue loss was present in 141 of the 167 bypasses. In the CPA group, 83% of tissue loss with DAR healed compared with 92% in the non-DAR (median time to healing, 66 vs 74 days). Similarly in the IPA group, 90% with DAR healed compared with 81% in the non-DAR (median time to healing, 96 vs 86 days). In the NPA group, only 75% with DAR healed compared with 73% in the non-DAR (median time to healing, 90 vs 135 days). There was a significant difference in healing and time to healing between the CPA/IPA and NPA groups (P = .0264)., Conclusions: The quality of the pedal arch did not influence the patency or the amputation-free survival rates. However, the rates for healing and time to healing were directly influenced by the quality of the pedal arch rather than the angiosome revascularized., (Copyright © 2013 Society for Vascular Surgery. Published by Mosby, Inc. All rights reserved.)

There is little data on outcome following lower limb bypass surgery in ethnic minorities in the United Kingdom. We looked at the results of distal bypass surgery in Afro-Caribbeans (AFCs) and compared it to caucasians (CAs). Patients undergoing distal bypass between 2004 and 2009 were analyzed. Life table analyses and log rank were used to compare graft patency and amputation-free survival. A total of 86 CA and 39 AFC patients, with a median age of 78 years and 73 years, respectively (P = .01), underwent bypass. There were more women in AFC groups (41.1%) compared to CA group (19.2%, P = .01). Tissue loss as indication for surgery was more in AFC than in CA group (92.3% vs73.9%, P = .03). Primary, primary-assisted and secondary patency rates, and amputation-free survival at 12 months for AFCs compared to CAs (51.3 vs 44.6; 85.2 vs 80.9; 91.2 vs 84.4; and 84.9 vs 75.1). Graft patency after lower limb distal revascularization in AFCs is comparable to CAs.

Objectives: Compare the outcome of distal (bypass to the crural arteries) versus ultradistal (bypass to the pedal arteries) bypasses in patients with critical leg ischaemia (CLI)., Design: Retrospective analysis of prospectively collected data of patients with CLI undergoing infra-popliteal bypass surgery is performed., Materials and Methods: Patients undergoing infra-popliteal bypass at a single institution between 2004 and 2010 are included. Patency rates at 1-year and amputation-free survival at 12 and 48 months are analysed., Results: Two hundred and thirty bypasses were performed in 209 consecutive patients (156 men, median age; 76 years, range; 19-96 years). One hundred and seventy nine (78%) bypass were classified as distal and 51 (22%) as ultradistal. The incidence of diabetes mellitus was significantly higher in the ultradistal group (p=0.0025). At 1-year, the distal group primary, assisted-primary and secondary patency rates were 61.7%, 83.1% and 87.4% compared to 61.9%, 87.4% and 87.4% in the ultradistal group respectively. Amputation-free survival at 12 and 48 months was 82.9% and 61.5% in the distal group compared to 83.0% and 64.9% in the ultradistal group., Conclusions: This study show that both distal and ultradistal bypass have comparable outcome regardless of the co-morbidities. The authors believe that elderly patients should be offered ultradistal bypass if indicated to avoid major amputation., (Copyright © 2011 European Society for Vascular Surgery. Published by Elsevier Ltd. All rights reserved.)

Introduction: The aim of this study is to analyse the role of cerebral oximetry in combination with awake testing in detecting cerebral ischaemia in patients undergoing carotid endarterectomy (CEA) under local anaesthesia (LA)., Methods: One hundred consecutive patients scheduled for CEA under LA were investigated. Regional oxygen saturation (rSO(2)) was measured with a cerebral oximeter. Cerebral ischaemia was assessed by awake testing in conjunction with rSO(2). Shunting was based solely on deterioration in conscious state assessed by awake testing. The correlation between awake testing and percentage fall in rSO(2) levels was statistically analysed., Results: Patients requiring general anaesthesia were excluded from analysis (n = 17). Seven patients developed deterioration in conscious state and an immediate drop in rSO(2) ≥20% following carotid cross-clamping. Two patients requiring shunting for non-neurological reasons were excluded from analysis. Two patients had a drop in rSO(2) ≥20%, but remained conscious and were not shunted. There were no permanent neurological deficits postoperatively. Statistical analysis showed a sensitivity of 100% with a specificity of 96% yielding a positive predictive value of 81% and negative predictive value of 100% for a ≥19% drop in rSO(2)., Conclusion: Cerebral oximetry using a cut off ≥19% drop in rSO(2) has a high sensitivity and specificity when compared with awake testing., (Copyright © 2010 European Society for Vascular Surgery. Published by Elsevier Ltd. All rights reserved.)