Nonlinear control of two-stage single-phase standalone photovoltaic system.

This paper presents a single-phase Photovoltaic (PV) inverter with its superior and robust control in a standalone mode. Initially, modeling and layout of the Buck-Boost DC-DC converter by adopting a non-linear Robust Integral Back-stepping controller (RIBSC) is provided. The controller makes use of a reference voltage generated through the regression plane so that the operating point corresponding to the maximum power point (MPP) could be achieved through the converter under changing climatic conditions. The other main purpose of the Buck-Boost converter is to act like a transformer and produce an increased voltage at the inverter input whenever desired. By not using a transformer makes the circuit size more compact and cost-effective. The proposed RIBSC is applied to an H-bridge inverter with an LC filter to produce the sinusoidal wave in the presence of variations in the output to minimize the difference between the output voltage and the reference voltage. Lyapunov stability criterion has been used to verify the stability and finite-time convergence of the overall system. The overall system is simulated in MATLAB/Simulink to test the system performance with different loads, varying climatic conditions and inverter reference voltages. The proposed methodology is compared with a back-stepping controller and Proportional Integral Derivative (PID) controller under rapidly varying climatic conditions. Results demonstrated that the proposed technique yielded a tracking time of 0.01s, a total harmonic distortion of 9.71% and a root means square error of 0.3998 in the case of resistive load thus showing superior control performance compared to the state-of-the-art control techniques.

Berberine ameliorates the progression of primary sclerosing cholangitis by activating farnesoid X receptor.

Primary sclerosing cholangitis (PSC) is a rare cholestatic disease characterized by biliary infiltration, hepatic fibrosis and bile duct destruction. To date, treatment options for PSC are very limited. Therefore, the current study is aimed to investigate the therapeutic potential of berberine (BBR) against PSC. The disease was induced by feeding the mice with 3,5-diethoxycarbonyl-1,4-dihydro-2,4,6-collidine (DDC) for four weeks. The serum biochemistry and liver histology were analyzed. Furthermore, the expression of farnesoid X receptor (FXR) was also evaluated by real-time PCR. The results indicated that berberine prevents the progression of PSC by modulating the expression of FXR which ultimately regulates other genes (including Cyp7A1 and BSEP) thus maintaining bile acids homeostasis. Furthermore, the docking analysis showed that berberine interacts with the binding pocket of FXR to activate the protein thus acting as an FXR agonist. In conclusion, data indicate that berberine protects the liver from PSC-related injury. This effect might be due to the modulation of FXR activity.

miR-4482 and miR-3912 aim for 3'UTR of ERG mRNA in prostate cancer.

Ets-related gene (ERG) is overexpressed as a fusion protein in prostate cancer. During metastasis, the pathological role of ERG is associated with cell proliferation, invasion, and angiogenesis. Here, we hypothesized that miRNAs regulate ERG expression through its 3'UTR. Several bioinformatics tools were used to identify miRNAs and their binding sites on 3'UTR of ERG. The selected miRNAs expression was analyzed in prostate cancer samples by qPCR. The miRNAs overexpression was induced in prostate cancer cells (VCaP) to analyze ERG expression. Reporter gene assay was performed to evaluate the ERG activity in response to selected miRNAs. The expression of ERG downstream target genes was also investigated through qPCR after miRNAs overexpression. To observe the effects of selected miRNAs on cell proliferation and migration, scratch assay was performed to calculate the cell migration rate. miR-4482 and miR-3912 were selected from bioinformatics databases. miR-4482 and -3912 expression were decreased in prostate cancer samples, as compared to controls (p<0.05 and p<0.001), respectively. Overexpression of miR-4482 and miR-3912 significantly reduced ERG mRNA (p<0.001 and p<0.01), respectively) and protein (p<0.01) in prostate cancer cells. The transcriptional activity of ERG was significantly reduced (p<0.01) in response to miR-4482 and-3912. ERG angiogenic targets and cell migration rate was also reduced significantly (p<0.001) after miR-4482 and -3912 over-expression. This study indicates that miR-4482 and -3912 can suppress the ERG expression and its target genes, thereby, halt prostate cancer progression. These miRNAs may be employed as a potential therapeutic target for the miRNA-based therapy against prostate cancer.

Perceived Social Support and Women's Empowerment and Their Associations with Pregnancy Experiences in Anxious Women: A Study from Urban Pakistan.

OBJECTIVES: Psychological distress in pregnancy is associated with adverse postnatal outcomes. We aimed to identify how social support and women's empowerment are associated with pregnancy-specific daily experiences among women suffering antenatal anxiety in Pakistan. METHODS: Data were collected as part of a randomized controlled trial of a psychosocial intervention for antenatal anxiety in a tertiary hospital in Pakistan. We included 594 women in early pregnancy (≤ 22 weeks) who endorsed mild to severe anxiety symptoms. Generalized linear regression models were used to analyze the associations of perceived social support and women's empowerment in relation to pregnancy-specific daily hassles and uplifts using a culturally adapted and psychometrically validated version of the Pregnancy Experience Scale-Brief. RESULTS: High social support was positively associated with frequency and intensity of positive pregnancy-specific experiences (B = 0.39, 95% CI 0.23-0.54 uplifts frequency; and B = 0.17, 95% CI 0.12-0.22 uplifts intensity), and was inversely associated with frequency of negative pregnancy-specific experiences (B = - 0.44, 95% CI - 0.66, - 0.22). Women's household empowerment was associated with greater uplifts frequency and intensity (B = 0.55, 95% CI 0.20-0.90 frequency; and B = 0.28, 95% CI 0.17-0.40 intensity). High social support and household empowerment were inversely related to PES hassle-to-uplift ratio scores. CONCLUSIONS FOR PRACTICE: Greater social support and household empowerment were associated with positive pregnancy-specific experiences in the context of antenatal anxiety in Pakistan.

Non-specialist-delivered psychosocial intervention for prenatal anxiety in a tertiary care setting in Pakistan: a qualitative process evaluation.

OBJECTIVES: A manualised cognitive-behavioural therapy-based psychosocial intervention for prenatal anxiety called Happy Mother Healthy Baby is being tested for its effectiveness through a randomised control trial in Pakistan. The aim of this study was to evaluate the intervention delivery process and the research process. DESIGN: Qualitative methods were used to explore in depth the intervention delivery and research process. SETTING: This process evaluation was embedded within a randomised control trial conducted in a tertiary care facility in Rawalpindi, Pakistan. PARTICIPANTS: Data were collected through in-depth interviews (n=35) with the trial participants and focus group discussions (n=3) with the research staff. Transcripts were analysed using a Framework Analysis. RESULTS: The evaluation of the intervention delivery process indicated that it can be effectively delivered by non-specialist providers trained and supervised by a specialist. The intervention was perceived to be culturally acceptable and appropriately addressing problems related to prenatal anxiety. Lack of awareness of 'talking' therapies and poor family support were potential barriers to participant engagement. The evaluation of the research process highlighted that culturally appropriate consent procedures facilitated recruitment of participants, while incentivisation and family involvement facilitated sustained engagement and retention. Lack of women's empowerment and mental health stigma were potential barriers to implementation of the programme. CONCLUSION: We conclude that non-specialists can feasibly deliver an evidence-based intervention integrated into routine antenatal care in a tertiary hospital. Non-specialist providers are likely to be more cost effective and less stigmatising. Inclusion of family is key for participant recruitment, retention and engagement with the intervention. TRIAL REGISTRATION NUMBER: NCT03880032.

Silymarin protects the liver from α-naphthylisothiocyanate-induced cholestasis by modulating the expression of genes involved in bile acid homeostasis.

Cholestasis is characterized by impaired bile flow which results in inflammation, cirrhosis, and ultimately liver failure. The current study is aimed to evaluate the anti-cholestatic effect of silymarin against α-naphthylisothiocyanate (ANIT) induced cholestasis. Mice were gavaged with various doses of silymarin or ursodeoxycholic acid (UDCA) for 19 days. Then they were challenged with α-naphthylisothiocyanate (ANIT) and after 48 hours the animals were sacrificed to obtain blood and liver sections. Serum levels of bilirubin, aspartate transaminase (AST), alanine transaminase (ALP), and liver histology were analyzed. mRNA expression of selected transporters (Bile salt export pump (BSEP) and sodium taurocholate cotransporting polypeptide (NTCP)) and proteins (farnesoid x receptor (FXR) and Cytochrome P450 Family 7 Subfamily A Member 1 (Cyp7a1)) involved in bile acids biosynthesis, excretion and uptake were also evaluated by quantitative PCR. The results indicated that the serum levels of bilirubin, AST, and ALP were significantly higher in a cholestatic model group as compared to an untreated control group. However, in silymarin groups, the serum level of these parameters is significantly lower than in a cholestatic model group. Liver histology also showed that silymarin prevents ANIT-induced hepatic injury. mRNA expression of FXR, BSEP, and NTCP was downregulated and expression of Cyp7a1 was upregulated in a cholestatic model group as compared to an untreated control group. However, in silymarin treatment groups, the expression of FXR, BSEP and NTCP was upregulated and the expression of Cyp7a1 was downregulated as compared to the cholestatic model group. In conclusion, silymarin could alleviate hepatic injury by modulating the expression of genes involved in bile acid homeostasis.

Cultural adaptation and psychometric validation of the Pregnancy Experience Scale-Brief version (PES-Brief) in Pakistani women with antenatal anxiety symptoms.

Background: Pregnancy experiences influence fetal and birth outcomes. There is scarcity of locally validated tools to assess pregnancy experiences. We aimed to validate the Pregnancy Experience Scale-Brief (PES-Brief) in pregnant Pakistani women with anxiety symptoms. Methods: A two-step process was used including 1) adaptation via translation/back-translation followed by cognitive interviewing with 10 participants and 2) factor analysis and validation with 605 women in Rawalpindi Pakistan who had mild-moderate symptoms of anxiety, attended the antenatal clinic, and were ≤22 weeks of gestation and ≥18 years old. We calculated internal consistency and reliability and conducted exploratory and confirmatory factor analyses. Results: Cultural adaptation led to inclusion of one item of the hassles subscale and exclusion of one item in the uplifts subscale, resulting in 9 uplifts and 11 hassles. Exploratory factor analysis supported a two-factor structure, with the adapted items exhibiting loading values of ≥0.24 for their respective factors. Internal consistency was demonstrated for uplifts (Cronbach's alpha = 0.89) and hassles (Cronbach's alpha = 0.85) subscales. Uplift intensity was moderately correlated with the Hospital Anxiety and Depression Scale anxiety subscale (r = 0.54, 95% CI:0.30-0.77). Conclusion: The Urdu PES-Brief is a reliable and valid tool for use in Pakistani pregnant women with antenatal anxiety. Future studies on its validity are needed on women without symptoms anxiety.

The Impact of the COVID-19 Pandemic on Pregnant Women with Perinatal Anxiety Symptoms in Pakistan: A Qualitative Study.

The impact of coronavirus disease 2019 (COVID-19) on people with existing mental health conditions is likely to be high. We explored the consequences of the pandemic on women of lower socioeconomic status with prenatal anxiety symptoms living in urban Rawalpindi, Pakistan. This qualitative study was embedded within an ongoing randomized controlled trial of psychosocial intervention for prenatal anxiety at a public hospital in Rawalpindi. The participants were women with symptoms of anxiety who had received or were receiving the intervention. In total, 27 interviews were conducted; 13 women were in their third trimester of pregnancy, and 14 were in their postnatal period. The data were collected through in-depth interviews and analyzed using framework analysis. Key findings were that during the pandemic, women experienced increased perinatal anxiety that was linked to greater financial problems, uncertainties over availability of appropriate obstetric healthcare, and a lack of trust in health professionals. Women experienced increased levels of fear for their own and their baby's health and safety, especially due to fear of infection. COVID-19 appears to have contributed to symptoms of anxiety in women already predisposed to anxiety in the prenatal period. Efforts to address women's heightened anxiety due to the pandemic are likely to have public health benefits.

In-Silico Analyses of Nonsynonymous Variants in the BRCA1 Gene.

BReast CAncer gene 1 (BRCA1)-a tumor suppressor gene plays an important role in the DNA repair mechanism. Several BRCA1 variants perturb its structure and function, including synonymous and nonsynonymous single nucleotide polymorphisms (SNPs). In the present study, we performed in-silico analyses of nonsynonymous SNPs (nsSNPs) of the BRCA1 gene. In total, 122 nsSNPs were retrieved from the NCBI SNP database and in-silico analyses were performed using computational prediction tools: SIFT, PROVEAN, Mutation Taster, PolyPhen-2, MutPred, and ConSurf. Of these tools, SIFT, PROVEAN, and Mutation Taster predicted 61 out of 122 nsSNPs as "damaging", based on structural homology analysis. PolyPhen-2 classified 22 nsSNPs as "probably damaging". These nsSNPs were further analyzed by MutPred to predict basic molecular mechanisms of amino acid alteration. ConSurf analysis predicted eleven conserved amino acid residues with structural and functional consequences. We identified five amino acid residues in the RING finger domain (L22, C39, H41, C44, and C47) and two in the BRCT domain (P1771 and I1707) with the potential to deter the BRCA1 protein function. This study provides insights into the effect of nsSNPs and amino acid substitutions in BRCA1.

RBF neural network based backstepping terminal sliding mode MPPT control technique for PV system.

The energy demand in the world has increased rapidly in the last few decades. This demand is arising the need for alternative energy resources. Solar energy is the most eminent energy resource which is completely free from pollution and fuel. However, the problem occurs when it comes to efficiency under different atmospheric conditions such as varying temperature and solar irradiance. To achieve its maximum efficiency, an algorithm of maximum power point tracking (MPPT) is needed to fetch maximum power from the photovoltaic (PV) system. In this article, a nonlinear backstepping terminal sliding mode control (BTSMC) is proposed for maximum power extraction. The system is finite-time stable and its stability is validated through the Lyapunov function. A DC-DC buck-boost converter is used to deliver PV power to the load. For the proposed controller, reference voltages are generated by a radial basis function neural network (RBF NN). The proposed controller performance is tested using the MATLAB/Simulink tool. Furthermore, the controller performance is compared with the perturb and observe (P&O) MPPT algorithm, Proportional Integral Derivative (PID) controller and backstepping MPPT nonlinear controller. The results validate that the proposed controller offers better tracking and fast convergence in finite time under rapidly varying conditions of the environment.

Silybum marianum (milk thistle) improves vancomycin induced nephrotoxicity by downregulating apoptosis.

Increased use of vancomycin for treating infections, and the associated risk of causing nephrotoxicity lead to the present study. The antioxidant and anti-apoptotic potential of Silybum marianum is used along with vancomycin to reduce adverse effects on the kidney. Vero cells (monkey kidney cells) and mice were used to test S. marianum extract on vancomycin induced nephrotoxicity. Vero cells were treated with different concentrations of vancomycin and S. marianum for 24 h for determination of cytotoxic potential and mRNA levels of apoptotic genes p53 , p21, and cyt-c were measured. For in-vivo studies mice were divided into five groups; G1 control (untreated), G2 vehicle (olive oil), G3 vancomycin treated (300 mg/kg body weight), G4 (S. marianum; 400 mg/kg bodyweight and vancomycin 300 mg/kg bodyweight simultaneously) and G5 (S. marianum 400 mg/kg bodyweight and vancomycin 300 mg/kg bodyweight treatment started after day 4 of S. marianum treatment). After 10 days histopathological analysis of mice kidneys was performed, serum urea and creatinine were analysed and mRNA expression of p53 , p21, and cyt-c was evaluated. Expression of p53, p21, and cyt-c in Vero cells was elevated in response to vancomycin treatment, whereas after S. marianum administration expression of these genes reduced. Vancomycin showed apoptosis in cells at the concentration of 6 mg/ml (LC50). Urea and creatinine levels in mice were increased in response to vancomycin administration and kidney histology showed an abnormality in functional units. The apoptotic cells were very visible in kidney structure in vancomycin treated group. These symptoms were however relieved in groups where treatment of S. marianum extract was given. mRNA expression of p53 , p21, and cyt-c also reduced in S. marianum treated groups of mice. S. marianum extract has protective effects against renal damage from vancomycin induced oxidative stress and relieves symptoms may be by downregulating apoptotic genes.

Nonlinear adaptive NeuroFuzzy feedback linearization based MPPT control schemes for photovoltaic system in microgrid.

Renewable energy resources connected to a single utility grid system require highly nonlinear control algorithms to maintain efficient operation concerning power output and stability under varying operating conditions. This research work presents a comparative analysis of different adaptive Feedback Linearization (FBL) embedded Full Recurrent Adaptive NeuroFuzzy (FRANF) control schemes for maximum power point tracking (MPPT) of PV subsystem tied to a smart microgrid hybrid power system (SMG-HPS). The proposed schemes are differentiated based on structure and mathematical functions used in FRANF embedded in the FBL model. The comparative analysis is carried out based on efficiency and performance indexes obtained using the power error between the reference and the tracked power for three cases; a) step change in solar irradiation and temperature, b) partial shading condition (PSC), and c) daily field data. The proposed schemes offer enhanced convergence compared to existing techniques in terms of complexity and stability. The overall performance of all the proposed schemes is evaluated by a spider chart of multivariate comparable parameters. Adaptive PID is used for the comparison of results produced by proposed control schemes. The performance of Mexican hat wavelet-based FRANF embedded FBL is superior to the other proposed schemes as well as to aPID based MPPT scheme. However, all proposed schemes produce better results as compared to conventional MPPT control in all cases. Matlab/Simulink is used to carry out the simulations.

Correction: Indirect adaptive soft computing based wavelet-embedded control paradigms for WT/PV/SOFC in a grid/charging station connected hybrid power system.

[This corrects the article DOI: 10.1371/journal.pone.0183750.].

Indirect adaptive soft computing based wavelet-embedded control paradigms for WT/PV/SOFC in a grid/charging station connected hybrid power system.

This paper focuses on the indirect adaptive tracking control of renewable energy sources in a grid-connected hybrid power system. The renewable energy systems have low efficiency and intermittent nature due to unpredictable meteorological conditions. The domestic load and the conventional charging stations behave in an uncertain manner. To operate the renewable energy sources efficiently for harvesting maximum power, instantaneous nonlinear dynamics should be captured online. A Chebyshev-wavelet embedded NeuroFuzzy indirect adaptive MPPT (maximum power point tracking) control paradigm is proposed for variable speed wind turbine-permanent synchronous generator (VSWT-PMSG). A Hermite-wavelet incorporated NeuroFuzzy indirect adaptive MPPT control strategy for photovoltaic (PV) system to extract maximum power and indirect adaptive tracking control scheme for Solid Oxide Fuel Cell (SOFC) is developed. A comprehensive simulation test-bed for a grid-connected hybrid power system is developed in Matlab/Simulink. The robustness of the suggested indirect adaptive control paradigms are evaluated through simulation results in a grid-connected hybrid power system test-bed by comparison with conventional and intelligent control techniques. The simulation results validate the effectiveness of the proposed control paradigms.

Adaptive control paradigm for photovoltaic and solid oxide fuel cell in a grid-integrated hybrid renewable energy system.

The hybrid power system (HPS) is an emerging power generation scheme due to the plentiful availability of renewable energy sources. Renewable energy sources are characterized as highly intermittent in nature due to meteorological conditions, while the domestic load also behaves in a quite uncertain manner. In this scenario, to maintain the balance between generation and load, the development of an intelligent and adaptive control algorithm has preoccupied power engineers and researchers. This paper proposes a Hermite wavelet embedded NeuroFuzzy indirect adaptive MPPT (maximum power point tracking) control of photovoltaic (PV) systems to extract maximum power and a Hermite wavelet incorporated NeuroFuzzy indirect adaptive control of Solid Oxide Fuel Cells (SOFC) to obtain a swift response in a grid-connected hybrid power system. A comprehensive simulation testbed for a grid-connected hybrid power system (wind turbine, PV cells, SOFC, electrolyzer, battery storage system, supercapacitor (SC), micro-turbine (MT) and domestic load) is developed in Matlab/Simulink. The robustness and superiority of the proposed indirect adaptive control paradigm are evaluated through simulation results in a grid-connected hybrid power system testbed by comparison with a conventional PI (proportional and integral) control system. The simulation results verify the effectiveness of the proposed control paradigm.

Orbital dermatofibrosarcoma protuberans with intracranial extension preceded by recurrent leiomyoma of the orbit: a case report.

INTRODUCTION: Dermatofibrosarcoma protuberans is a rare, locally aggressive cutaneous tumor of intermediate to low-grade malignancy. COL1A1-PDGFß translocation is specific to dermatofibrosarcoma protuberans, where the abnormally fused COL1A1-PDGFß gene directs formation of an abnormal combined (fusion) protein that researchers believe to ultimately function like the platelet-derived growth factor-beta protein. CASE PRESENTATION: In this report, we present a case of a 63-year-old Asian man with dermatofibrosarcoma protuberans of the right orbit with intracranial extension. He had a prior history of recurrent leiomyomas at the identical site. He underwent near-total en bloc resection of the tumor through a wide craniectomy with a 6 cm rim of the frontal scalp, allowing the tumor to be resected en bloc, leaving negative margins. Microscopically, the tumor comprised spindle cells with mild nuclear atypia and a low mitotic index embedded in a spiraling pattern of decussating fascicles consistent with dermatofibrosarcoma protuberans. The lesion was positive for CD34 and BCL2. Following resection, the patient was started on imatinib mesylate therapy (800 mg/day). CONCLUSIONS: We propose that platelet-derived growth factor, which has been implicated in the progression of leiomyomas by augmenting mitogenesis, may have acted in an autocrine manner to cause cell division, which may have led to the development of dermatofibrosarcoma protuberans in our patient. Further research is imperative to find certain molecular associations between the discussed soft tissue tumors. Also important is the effective utilization of platelet-derived growth factor receptor kinase inhibitors to prevent transformation to any platelet-derived growth factor-driven tumor, which in our patient was a dermatofibrosarcoma protuberans.

Intramedullary dermoid cyst with relatively atypical symptoms: a case report and review of the literature.

BACKGROUND: Intraspinal dermoid cysts are rare and benign tumors that occur primarily due to the defective closure of the neural tube, an ectodermal derivative, during the process of development. They are slow-growing tumors manifesting in the second and third decades of life. CASE PRESENTATION: We present here a case of a 14-year-old Sindhi boy with a six-month history of paraparesis of the lower limbs and a progressive loss of power of grade 3/5, and hypoesthesia in the L4/L5 dermatomes of his right lower limb. A plain magnetic resonance imaging scan revealed a well-demarcated intraspinal intramedullary cyst containing an abscess at the level of T12 and L1 causing localized cord compression, which was producing the symptoms. Near total excision of the cyst was successfully performed and was sent for biopsy, which revealed keratinocytes and keratin flakes. With one month of follow-up, along with physiotherapeutic management, the patient gradually improved and was able to walk without support. CONCLUSIONS: Critical evaluation of every case with aggravating symptoms should be carried out, and neurological and radiological examinations should be conducted to ensure the well-being of patients.