H∞ based control of a DC/DC buck converter feeding a constant power load in uncertain DC microgrid system

DC microgrids are gaining more and more popularity and are becoming a more viable alternative to AC microgrids (MGs) due to their advantages in terms of simpler power converter stages, flexible control algorithms and the absence of synchronization and reactive power. However, DC-MGs are prone to instability issues associated with the presence of nonlinear loads such as constant power loads (CPL) known by their incremental negative impedance (INI), which may lead to voltage collapse of the main DC Bus. In this paper, -based controller of a source side buck converter is designed to avoid the instability issues caused by the load-side converter acting as a CPL. Besides, the proposed controller allows a perfect rejection of all perturbations that may arise from parameter variations, input voltage and CPL current fluctuations. The design process of H-based controller is based on the Golver Doyle Optimization Algorithm (GDOA), which requires an augmented system extracted from the small-signal model of the DC/DC converter including the mathematical model of parameter variations and overall external perturbations. The​ based controller involves the use of weight functions in order to get the desired performances. The proposed controller is easy to implement and lead to reducing the implementation cost and avoid the use of current measurement that may have some disadvantages. The derived controller is validated by simulation performed in Psim software and experimental setup

Vertebral Augmentation: State of the Art

Osteoporotic vertebral compression fractures (OVF) are an increasing public health problem. Cement augmentation (vertebroplasty of kyphoplasty) helps stabilize painful OVF refractory to medical treatment. This stabilization is thought to improve pain and functional outcome. Vertebroplasty consists of injecting cement into a fractured vertebra using a percutaneous transpedicular approach. Balloon kyphoplasty uses an inflatable balloon prior to injecting the cement. Although kyphoplasty is associated with significant improvement of local kyphosis and less cement leakage, this does not result in long-term clinical and functional improvement. Moreover, vertebroplasty is favored by some due to the high cost of kyphoplasty. The injection of cement increases the stiffness of the fracture vertebrae. This can lead, in theory, to adjacent OVF. However, many studies found no increase of subsequent fracture when comparing medical treatment to cement augmentation. Kyphoplasty can have a protective effect due to restoration of sagittal balance

Practice of non-pharmaceutical interventions against COVID-19 and reduction of the risk of influenza-like illness: a cross-sectional population-based study

INTRODUCTION: While the widespread implementation of the non-pharmaceutical interventions was intended to contain the COVID-19 pandemic, such measures could be also effective in limiting the spread of other respiratory infections. This study aimed to examine the association between the implementation of personal protective measures and the occurrence of influenza-like illnesses (ILI) in the general population. METHODS: An online retrospective cross-sectional observational study was conducted in April 2021 to assess cases of ILI among Lebanese adults aged 18 years and above, from all Lebanese governorates during the 2020-2021 flu season. Data were collected using a convenience sampling method. In addition to their socio-demographic information, participants were asked about their frequency of implementing personal protective measures and if they have experienced symptoms of ILI in the previous 6 months. The overall score of the personal protective measures was computed. Multivariable logistic regression was performed to examine the association between participants' level of adoption of personal protective measures against COVID-19 and the occurrence of ILI. RESULTS: Among the 1019 Lebanese adults participating in this study, 352 (34.54%) of them reported symptoms of ILI between October 2020 and March 2021. Lebanese adults who wore their facemasks frequently or always were less likely to suffer from symptoms of ILI than others who did not wear the mask (aOR = 0.452, 95% CI = 0.349-0.693, p < 0.001). Similarly, adults who adopt the following protective measures washing hands (aOR = 0.608, 95% CI = 0.524-0.922, p < 0.001), respecting cough etiquette (aOR = 0.763, 95% CI = 0.598-0.918, p < 0.001), disinfecting surface (aOR = 0.892, 95% CI = 0.632-0.911, p = 0.012), avoiding crowded places (aOR = 0.739, 95% CI = 0.688-0.903, p = 0.049), respecting physical distancing (aOR = 0.646, 95% CI = 0.482-0.833, p = 0.031) on a regular basis (frequently/always) were less likely to report symptoms of influenza-like illnesses when compared with those who did not adhere at all to these measures. CONCLUSION: Our study highlighted the potential of personal protective measures against COVID-19 in reducing the transmission of respiratory infections such as ILI. Such findings might be invested during influenza season, particularly among groups at high risk of developing severe complications. Exploring trends detected by the national severe acute respiratory infection surveillance system is recommended to confirm the utility of these measures

Carbohydrates and lipids metabolic enzymes inhibitory, antioxidant, antimicrobial and cytotoxic potentials of Anchusa ovata Lehm. from Palestine

Introduction: Throughout history, therapeutically active plant products have received substantial attention due to their valuable role in the discoveries of specific medications. The aim of this study was to assess, for the first time, the antimicrobial, antioxidant, antilipase, anti-α-amylase and cytotoxic properties of four fractions derived from Anchusa ovata Lehm. (AO) leaves. Methods: Antioxidant, antilipase and anti-amylase potentials of (AO) were established using DPPH (1,1-diphenyl- 2-picrylhydrazyl), p-nitrophenyl butyrate and dinitro-salicylic acid procedures, respectively, while antimicrobial activity was conducted using broth microdilution assay against eight Gram-positive, Gram-negative bacterial strains in addition to one fungal strain. Moreover, the MTS [3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)- 2-(4-sulfophenyl)-2H-tetrazolium] cytotoxic assay was utilized against cervical cancer cells (HeLa). Results: The methanol fraction of AO showed potential antioxidant, antilipase, and α-amylase inhibitory activities with IC50 values of 9.55 ± 0.13, 53.7 ± 0.41 and 16.55 ± 1.84 μg/ml, respectively compared with the positive controls Trolox, Orlistat and Acarbose that had IC50 values of 3.23 ± 0.92, 12.3 ± 0.35 and 28.18 ± 1.22 μg/ml, respectively. Moreover, the hexane, acetone, and methanol fractions had wide ranges of antimicrobial potential. In addition, the cytotoxic activity outcomes which showed the best activity was for the aqueous followed by acetone, hexane and methanol fractions with IC50 values of 1.04, 2.72, 3.96 and 17.67 mg/ ml, respectively. Conclusion: Our data demonstrate a wide range of biological characteristics for each AO plant fraction. This profiling information about the methanol fraction provided important data for further research and pharmaceutical applications.The authors would like to acknowledge the Faculty of Medicine and Health Sciences at An-Najah National University for facilitating the accomplishment of the current study

Total phenolic contents, cytotoxic, free radicals, porcine pancreatic α-amylase, and lipase suppressant activities of Artemisia dracunculus plant from Palestine

Artemisia dracunculus: L. (A. dracunculus) is a popular vegetable and spice cultivated across many Middle Eastern countries. The herb’s aqueous extract has significant folkloric medicinal importance for treating various disorders. Hence, the present investigation aimed to investigate A. dracunculus hydrophilic extract phytochemical constituents and pleiotropic biological potentials, as no previous studies have investigated the antilipase and anti-α-amylase effects of the A. dracunculus plant. Total phenol content and phytochemical screening assays were performed utilizing standard analytical methods. While the α-amylase inhibition, free radical-scavenging, antilipase, and cytotoxic activities were determined using dinitrosalicylic acid (DNSA), DPPH, p-nitrophenyl butyrate (PNPB), and MTS assays, respectively. The standard phytochemical analysis of A. dracunculus aqueous extract shows that this extract contains only a phenolic group. The total phenol content was 0.146 ± 0.012 mg GAE/g of the plant dry extract. The A. dracunculus aqueous extract exhibited potent DPPH free radical inhibitory (IC50 dose of 10.71 ± 0.01 μg/mL) and anti-lipase activities (IC50 dose of 60.25 ± 0.33 μg/mL) compared with Trolox (IC50 = 5.7 ± 0.92 μg/mL) and Orlistat (IC50 = 12.3 ± 0.35 μg/mL), respectively. However, it showed a weak anti-α-amylase effect (IC50 value &gt; 1,000 μg/mL) compared with Acarbose (IC50 = 28.18 ± 1.27 μg/mL). A. dracunculus has a cytotoxic effect against the HeLa cancer cell line compared with the chemotherapeutic agent Doxorubicin. The extract has the same percent of inhibition as Doxorubicin (99.9%) at 10 mg/mL. Overall, these results pointed out for the first time the importance of considering A. dracunculus effects as a favorite candidate for preventing and treating metabolic disorders. Also, our results confirm the findings of previous reports on the role of A. dracunculus in the management of cancer and disorders resulting from the accumulation of harmful free radicals. On the contrary, the current study concluded that the antidiabetic role of A. dracunculus could be minimal. Further in-depth investigations are urgently warranted to explore the importance of A. dracunculus in pharmaceutical production

Dynamics and role of antibodies to Plasmodium falciparum merozoite antigens in children living in two settings with differing malaria transmission intensity

AbstractBackgroundYoung infants have reduced susceptibility to febrile malaria compared with older children, but the mechanism for this remains unclear. There are conflicting data on the role of passively acquired antibodies. Here, we examine antibody titres to merozoite surface antigens in the protection of children in their first two years of life in two settings with differing malaria transmission intensity and compare these titres to previously established protective thresholds.MethodsTwo cohorts of children aged four to six weeks were recruited in Banfora, Burkina and Keur Soce, Senegal and followed up for two years. Malaria infections were detected by light microscopic examination of blood smears collected at active and passive case detection visits. The titres of antibodies to the Plasmodium falciparum recombinant merozoite proteins (AMA1-3D7, MSP1-19, MSP2-Dd2, and MSP3-3D7) were measured by enzyme-linked immunosorbent assay at 1–6, 9, 12, 15 and 18 months of age and compared with the protective thresholds established in Kenyan children.ResultsAntibody titres were below the protective thresholds throughout the study period and we did not find any association with protection against febrile malaria. Antibodies to AMA1 and MSP1-19 appeared to be markers of exposure in the univariate analysis (and so associated with increasing risk) and adjusting for exposure reduced the strength and significance of this association.ConclusionThe antibody levels we measured are unlikely to be responsible for the apparent protection against febrile malaria seen in young infants. Further work to identify protective antibody responses might include functional assays and a wider range of antigens

MMSE is an independent prognostic factor for survival in primary central nervous system lymphoma

Introduction: To assess the value of the Mini-Mental State Examination (MMSE)-score at baseline in predicting survival in adult primary central nervous system lymphoma (PCNSL) patients. Methods: In the HOVON 105/ ALLG NHL 24 phase III study patients with newly-diagnosed PCNSL were randomized between high-dose methotrexate-based chemotherapy with or without rituximab. Data on potential (MMSE-score), and known baseline prognostic factors (age, performance status, serum LDH, cerebrospinal fluid total protein, involvement of deep brain structures, multiple cerebral lesions, and the IELSG-score) were collected prospectively. Multivariable stepwise Cox regression analyses were used to assess the prognostic value of all factors on progression-free survival (PFS) and overall survival (OS) among patients with available MMSE score at baseline. Age was analyzed as continuous variable, the MMSE-score both as a continuous and as a categorical variable. Results: In univariable analysis, age, MMSE-score and whether the patient received rituximab were statistically significantly prognostic factors for PFS. Age and MMSE-score were statistically significantly associated with OS. In a multivariable analysis of the univariately significant factors only MMSE-score was independently associated with the survival endpoints, as a continuous variable (HR for PFS 1.04, 95% CI 1.01–1.08; OS 1.06 (95% CI 1.02–1.10) and as categorical variable HR (< 27 versus ≥ 27 for PFS 1.55 (1.02–2.35); OS 1.68 (1.05–2.70). In our population, performance status, serum LDH, and CSF protein level were not of prognostic value. Conclusion: Neurocognitive disturbances, measured with the MMSE at baseline, are an unfavorable prognostic factor for both PFS and OS in adult PCNSL patients up to 70 years-old

Neurocognitive functioning and radiologic changes in primary CNS lymphoma patients:results from the HOVON 105/ALLG NHL 24 randomized controlled trial

BACKGROUND: To analyze the effect of treatment on neurocognitive functioning and the association of neurocognition with radiological abnormalities in primary central nervous system lymphoma (PCNSL). METHODS: One hundred and ninety-nine patients from a phase III trial (HOVON 105/ALLG NHL 24), randomized to standard chemotherapy with or without rituximab, followed in patients ≤60 years old by 30-Gy whole-brain radiotherapy (WBRT), were asked to participate in a neuropsychological evaluation before and during treatment, and up to 2 years posttreatment. Scores were transformed into a standardized z-score; clinically relevant changes were defined as a change in z-score of ≥1 SD. The effect of WBRT was analyzed in irradiated patients. All MRIs were centrally assessed for white matter abnormalities and cerebral atrophy, and their relation with neurocognitive scores over time in each domain was calculated. RESULTS: 125/199 patients consented to neurocognitive evaluation. Statistically significant improvements in neurocognition were seen in all domains. A clinically relevant improvement was seen only in the motor speed domain, without differences between the arms. In the follow-up of irradiated patients (n = 43), no change was observed in any domain score, compared to after WBRT. Small but significant inverse correlations were found between neurocognitive scores over time and changes in white matter abnormalities (regression coefficients: −0.048 to −0.347) and cerebral atrophy (−0.212 to −1.774). CONCLUSIONS: Addition of rituximab to standard treatment in PCNSL patients did not impact neurocognitive functioning up to 2 years posttreatment, nor did treatment with 30-Gy WBRT in patients ≤60 years old. Increased white matter abnormalities and brain atrophy showed weak associations with neurocognition

Therapeutically expanded human regulatory T-cells are super-suppressive due to HIF1A induced expression of CD73.

The adoptive transfer of regulatory T-cells (Tregs) is a promising therapeutic approach in transplantation and autoimmunity. However, because large cell numbers are needed to achieve a therapeutic effect, in vitro expansion is required. By comparing their function, phenotype and transcriptomic profile against ex vivo Tregs, we demonstrate that expanded human Tregs switch their metabolism to aerobic glycolysis and show enhanced suppressive function through hypoxia-inducible factor 1-alpha (HIF1A) driven acquisition of CD73 expression. In conjunction with CD39, CD73 expression enables expanded Tregs to convert ATP to immunosuppressive adenosine. We conclude that for maximum therapeutic benefit, Treg expansion protocols should be optimised for CD39/CD73 co-expression

Survival, neurocognitive function, and health-related quality of life outcomes after rituximab-methotrexate, BCNU, teniposide, and prednisolone for primary CNS lymphoma:Final results of the HOVON 105/ALLG NHL 24 study

Background. Studies on the efficacy of rituximab in primary CNS lymphoma (PCNSL) reported conflicting results. Our international randomized phase 3 study showed that the addition of rituximab to high-dose methotrexate, BCNU, teniposide, and prednisolone (MBVP) in PCNSL was not efficacious in the short term. Here we present long-term results after a median follow-up of 82.3 months. Methods. One hundred and ninety-nine eligible newly diagnosed, nonimmunocompromised patients with PCNSL aged 18–70 years with WHO performance status 0–3 was randomized between treatment with MBVP chemotherapy with or without rituximab, followed by high-dose cytarabine consolidation in responding patients, and reduced-dose WBRT in patients aged ≤ 60 years. Event-free survival was the primary endpoint. Overall survival rate, neurocognitive functioning (NCF), and health-related quality of life (HRQoL) were additionally assessed, with the IPCG test battery, EORTC QLQ-C30 and QLQ-BN20 questionnaires, respectively. Results. For event-free survival, the hazard ratio was 0.85, 95% CI 0.61–1.18, P = .33. Overall survival rate at 5 years for MBVP and R-MBVP was 49% (39–59) and 53% (43–63) respectively. In total, 64 patients died in the MBVP arm and 55 in the R-MBVP arm, of which 69% were due to PCNSL. At the group level, all domains of NCF and HRQoL improved to a clinically relevant extent after treatment initiation, and remained stable thereafter up to 60 months of follow-up, except for motor speed which deteriorated between 24 and 60 months. Although fatigue improved initially, high levels persisted in the long term. Conclusions. Long-term follow-up confirms the lack of added value of rituximab in addition to MBVP and HD-cytarabine for PCNSL.</p