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Faults in photovoltaic (PV) modules may occur due to various environmental and physical factors. To prevent faults and minimize investment losses, fault diagnosis is crucial to ensure uninterrupted power production, extended operational lifespan, and a high level of safety in PV modules. Recent advancements in inspection techniques and instrumentation have significantly reduced the cost and time required for inspections. A novel stacking-based ensemble approach was performed in the present study for the accurate classification of PV module visible faults. The present study utilizes AlexNet (a pre-trained network) to extract image features from the aerial images of PV modules with the aid of MATLAB software. Furthermore, J48 algorithm was applied to perform the feature selection task to determine the most relevant features. The features derived as output from the J48 algorithm were passed onto train eight base classifiers namely, Naïve Bayes, logistic regression (LR), J48, random forest (RF), multilayer perceptron (MLP), logistic model tree (LMT), support vector machines (SVM) and k-nearest neighbors (kNN). The best performing five classifiers on the front run with higher classification accuracies were selected to formulate three categories of stacking ensemble groups as follows: (i) three-class ensemble (SVM, kNN, and LMT), (ii) four-class ensemble (SVM, kNN, LMT, and RF), and (iii) five-class ensemble (SVM, kNN, LMT, RF, and MLP). A comparison in the performance of the aforementioned stacked ensembles was evaluated with different meta classifiers. The obtained results infer that the four-class stacking ensemble model (SVM, kNN, LMT, and RF) with RF as the predictor achieved the highest possible classification accuracy of 99.04%., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2024 The Authors.)

Background: Many different intestinal parasite species can co-occur in the same population. However, classic diagnostic tools can only frame a particular group of intestinal parasite species. Hence, one or two tests do not suffice to provide a complete picture of infecting parasite species in a given population. The present study investigated intestinal parasitic infections in Beira, Mozambique, i.e. in the informal settlement of Inhamudima. Diagnostic accuracy of five classical microscopy techniques and real-time PCR for the detection of a broad spectrum of parasites was compared., Methodology/principal Findings: A cross-sectional population-based survey was performed. One stool sample per participant (n = 303) was examined by direct smear, formal-ether concentration (FEC), Kato smear, Baermann method, coproculture and real-time PCR. We found that virtually all people (96%) harbored at least one helminth, and that almost half (49%) harbored three helminths or more. Remarkably, Strongyloides stercoralis infections were widespread with a prevalence of 48%, and Ancylostoma spp. prevalence was higher than that of Necator americanus (25% versus 15%), the hookworm species that is often assumed to prevail in East-Africa. Among the microscopic techniques, FEC was able to detect the broadest spectrum of parasite species. However, FEC also missed a considerable number of infections, notably S. stercoralis, Schistosoma mansoni and G. intestinalis. PCR outperformed microscopy in terms of sensitivity and range of parasite species detected., Conclusions/significance: We showed intestinal parasites-especially helminths-to be omnipresent in Inhamudima, Beira. However, it is a challenge to achieve high diagnostic sensitivity for all species. Classical techniques such as FEC are useful for the detection of some intestinal helminth species, but they lack sensitivity for other parasite species. PCR can detect intestinal parasites more accurately but is generally not feasible in resource-poor settings, at least not in peripheral labs. Hence, there is a need for a more field-friendly, sensitive approach for on-the-spot diagnosis of parasitic infections., Competing Interests: The authors have declared that no competing interests exist.

A best evidence topic in transplant surgery was written according to a structured protocol. The question addressed was: In patients undergoing pancreatic transplantation alone, does enteric drainage or bladder drainage of exocrine secretions provide the best graft survival? A total of 155 papers were identified using the search protocol described, of which four retrospective cohort studies represented the best evidence available to answer the clinical question. The authors, journal, date and country of publication, study type, patient group studied, relevant outcomes and results of these papers are tabulated. Three of the four studies demonstrated no significant difference in graft survival between enteric drainage and bladder drainage at 6 months or 1 year. This included the largest and most recent study which showed that patient survival, graft survival and technical failure rates at 1 year were equal between the two duct management techniques. However, one study indicated lower graft survival at 1 year with enteric drainage due to a higher technical failure rate. Therefore, the clinical bottom line is that there is no significant difference in graft survival between enteric drainage or bladder drainage of pancreatic exocrine secretions for pancreas transplants alone. There is some evidence that enteric drainage may be associated with higher technical failure and higher graft rejection but this has not been universally demonstrated. Given the historical nature of all the available evidence, further appropriately powered and randomised Level 1 studies are necessary to clarify this important issue., (Copyright © 2015 IJS Publishing Group Limited. Published by Elsevier Ltd. All rights reserved.)

Superoxide and peroxide handling capacity (SPHC) is an important determinant of oxidative stress. Neurotoxic impacts of aluminum are associated with oxidant imbalance. Here, we studied the influence of aluminum on oxidative stress parameters, antioxidative enzymes and SPHC of thalamic area on pro-oxidant (ethanol) and antioxidant (α-tocopherol) exposure. Two sets of male Wistar rats were divided into 8 groups (6 each) and exposed to aluminum (10 mg/Kg body wt.), ethanol (0.6 g/Kg body wt.) and α-tocopherol (5 IU/day) for 4 wk, each having respective control group. Levels of reduced glutathione (GSH), lipid peroxidation (TBARS) along with activities of superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx) and glutathione reductase (GR) of thalamic area were estimated for each group. Glutathione-independent superoxide peroxide handling capacity (GI-SPHC) and glutathione-dependent superoxide peroxide handling capacity (GD-SPHC) were calculated from the GPx, CAT and SOD values. Concomitant exposure to aluminum and ethanol demonstrated significant increase in SOD activity and significant decrease in GPx activity compared to the control group, while lone aluminum-exposed rats showed raised GR activity, without alterations in GPx and SOD activities. However, significant reduction of both GI- and GD- SPHC were found in ethanol-exposed groups. α-Tocopherol supplementation could resist most of the alterations. In addition, current antioxidant exposure reduced the inherent GD-SPHC, and thus, made thalamic area more vulnerable to oxidant threat. The present study corroborates the thalamic susceptibility to aluminum-augmented oxidant imbalance and suggests cautious use of antioxidant supplementation against neurodegenerative disorders.

Background: In an effort to enhance accuracy of diagnosis of Schistosoma haematobium, this study explores day-to-day variability and diagnostic performance of real-time PCR for detection and quantification of Schistosoma DNA compared to other diagnostic tools in an endemic area before and after treatment., Methodology: Previously collected urine samples (N = 390) from 114 preselected proven parasitological and/or clinical S. haematobium positive Kenyan schoolchildren were analyzed by a Schistosoma internal transcribed spacer-based real-time PCR after 14 years of storage. Pre-treatment day-to-day fluctuations of PCR and microscopy over three consecutive days were measured for 24 children using intra-class correlation coefficient. A combined 'gold standard' (PCR and/or microscopy positive) was used to measure sensitivity and negative predictive value (NPV) of several diagnostic tools at baseline, two and 18 months post-treatment with praziquantel., Principal Findings: All 24 repeatedly tested children were PCR-positive over three days with little daily variation in median Ct-values, while 83.3% were found to be egg-positive for S. haematobium at day 1 and 75.0% at day 2 and 3 pre-treatment, signifying daily fluctuations in microscopy diagnosis. Of all 114 preselected schoolchildren, repeated microscopic measurements were required to detect 96.5% versus 100% of positive pre-treatment cases by single PCR. At two months post-treatment, microscopy and PCR detected 22.8% versus 69.3% positive children, respectively. Based on the 'gold standard', PCR showed high sensitivity (>92%) as compared to >31% sensitivity for microscopy, both pre- and post-treatment., Conclusions/significance: Detection and quantification of Schistosoma DNA in urine by real-time PCR was shown to be a powerful and specific diagnostic tool for detection of S. haematobium infections, with less day-to-day variation and higher sensitivity compared to microscopy. The superior performance of PCR before, and two and 18 months post-treatment provides a compelling argument for PCR as an accurate and reproducible tool for monitoring treatment efficacy.

Aluminum is an omnipresent neurotoxicant and has been associated with several neuropathological disorders. Cerebrum and cerebellum have been shown to face augmented oxidative stress when animals are exposed to aluminum and high doses of ethanol. To establish the link between oxidative stress and neurobehavioral alterations, the present study was conducted to determine the extent of oxidative stress in low levels of pro-oxidant (ethanol exposure) status of the functionally discrete regions of the cerebrum. Male Wistar rats were exposed to aluminum (10 mg/kg body wt) and ethanol (0.2-0.6 g/kg body wt) for 4 weeks. Spontaneous motor activity (SMA) and Rota-Rod performances (RRP) were recorded weekly during the period of exposure. At the end of 4th week, oxidative stress parameters were determined from the homogenized cerebral tissue. GSH-independent superoxide peroxide handling capacity (GI-SPHC) and GSH-dependent superoxide peroxide handling capacity (GD-SPHC) were determined for FC and TC upon exposure to ethanol in the absence and presence of aluminum exposure. Aluminum was found to augment the oxidative stress at higher doses (0.6 g Ethanol/kg body wt) of ethanol, particularly in FC. The SPHC of FC was also found to be compromised significantly in aluminum-ethanol co-exposed animals. It was concluded that even though the manifestation of oxidative stress was not observed as revealed by assaying the widely used oxidative stress biochemical markers (indices), aluminum and ethanol (low doses) exposure induced alterations in the handling capacity of oxidant imbalance that could be recognized by studying the SPHC of FC. Comparison of GD-SPHC and GI-SPHC offered a possible mechanism of compromised SPHC in FC. This observation is likely to offer insights into the mechanism of association between aluminium exposure and behavioral changes in neurodegenerative disorders towards therapeutic strategies for these disorders.

In the title compound, C28H24F6N2O3, the mean plane of the central pyrazoline ring forms dihedral angles of 2.08 (9) and 69.02 (16)° with the 2-benz-yloxy-6-hy-droxy-4-methyl-phenyl and 3,5-bis-(tri-fluoro-meth-yl)phenyl rings, respectively. The dihedral angle between the mean planes of the pyrazoline and 3,5-bis-(tri-fluoro-meth-yl)phenyl rings is 68.97 (9)°. An intra-molecular O-H⋯N hydrogen bond is observed, which forms an S(6) graph-set motif. In the crystal, pairs of weak C-H⋯F halogen inter-actions link the mol-ecules into inversion dimers while molecular chains along [100] are formed by C-H⋯O contacts.

Background: Prisoners are at high risk of developing tuberculosis (TB), causing morbidity and mortality. Prison facilities encounter many challenges in TB screening procedures and TB control. This review explores screening practices for detection of TB and describes limitations of TB control in prison facilities worldwide., Methods: A systematic search of online databases (e.g., PubMed and Embase) and conference abstracts was carried out. Research papers describing screening and diagnostic practices among prisoners were included. A total of 52 articles met the inclusion criteria. A meta-analysis of TB prevalence in prison facilities by screening and diagnostic tools was performed., Results: The most common screening tool was symptom questionnaires (63·5%), mostly reporting presence of cough. Microscopy of sputum with Ziehl-Neelsen staining and solid culture were the most frequently combined diagnostic methods (21·2%). Chest X-ray and tuberculin skin tests were used by 73·1% and 50%, respectively, as either a screening and/or diagnostic tool. Median TB prevalence among prisoners of all included studies was 1,913 cases of TB per 100,000 prisoners (interquartile range [IQR]: 332-3,517). The overall annual median TB incidence was 7·0 cases per 1000 person-years (IQR: 2·7-30·0). Major limitations for successful TB control were inaccuracy of diagnostic algorithms and the lack of adequate laboratory facilities reported by 61·5% of studies. The most frequent recommendation for improving TB control and case detection was to increase screening frequency (73·1%)., Discussion: TB screening algorithms differ by income area and should be adapted to local contexts. In order to control TB, prison facilities must improve laboratory capacity and frequent use of effective screening and diagnostic tools. Sustainable political will and funding are critical to achieve this.

In recent years there has been an increasing search for new antifungal compounds due to the side effects of conventional antifungal drugs and fungal resistance. The aims of this study were to test in vitro the activity of thymol, eugenol, estragole and anethole and some O-methyl-derivatives (methylthymol and methyleugenol) against Candida spp. and Microsporum canis. The broth microdilution method was used to determine the minimum inhibitory concentration (MIC). The minimum fungicidal concentrations (MFC) for both Candida spp. and M. canis were found by subculturing each fungal suspension on potato dextrose agar. Thymol, methylthymol, eugenol, methyl-eugenol, anethole, estragole and griseofulvin respectively, presented the following MIC values against M. canis: 4.8-9.7; 78-150; 39; 78-150; 78-150; 19-39 µg/mL and 0.006-2.5 mg/mL. The MFC values for all compounds ranged from 9.7 to 31 µg/mL. Concerning Candida spp, thymol, methylthymol, eugenol, methyleugenol, anethole, estragole and amphotericin, respectively, showed the following MIC values: 39; 620-1250; 150-620; 310-620; 620; 620-1250 and 0.25-2.0 mg/mL. The MFC values varied from 78 to 2500 µg/mL. All tested compounds thus showed in vitro antifungal activity against Candida spp. and M. canis. Therefore, further studies should be carried out to confirm the usefulness of these alkylphenols in vivo.

Wettability studies are of importance for electronic devices. Various methods are known to convert the hydrophobic substrates to hydrophilic substrates, but the studies on the relative dependence of wettability with varying concentrations of an aqueous system are meager. The wetting of different substrates with varying concentration of 1,4-dioxane in water is investigated and the results of concentration dependence of wetting are presented. The FTIR spectrum shows a blue shift of the OH peak--a feature typical of aqueous-1,4-dioxane systems. Concentration dependence of dielectric permittivity of this system also showed an anomaly., (Copyright © 2011 Elsevier Inc. All rights reserved.)

We explore the effects of nanoscale morphology of supporting solid substrates on alignment, defects, and director structures exhibited by thin films of triphenylamine-based discotic liquid crystals. Fluorescence confocal polarizing microscopy and intrinsic polarized fluorescence properties of studied molecules are used to visualize three-dimensional director fields in the liquid crystal films. We demonstrate that, by controlling surface anchoring on supporting or confining solid substrates such as those of carbon nanotube electrodes on glass plates, both uniform homeotropic and in-plane (edge-on) alignment and nonuniform structures with developable domains can be achieved for the same discotic liquid crystal material.

Rearrangements of the mixed lineage leukemia (MLL) gene at 11q23 commonly occur in infants with CALLA negative B lymphoblastic leukemia (B-ALL). Most often, these are detected by conventional karyotyping; however, fluorescent in-situ hybridization (FISH) with the help of a dual-color break-apart probe is used to identify cryptic translocations. When there is an MLL gene translocation, the usual FISH signal pattern is 1 red-1 green-1 yellow fusion signal pattern. We present a case of an infant with CALLA negative precursor B-ALL with a characteristic translocation t(4;11) (q21;q23), however, with an unusual MLL FISH signal pattern.

Recently, the topographic patterning of surfaces by lithography and nanoimprinting has emerged as a new and powerful tool for producing single structural domains of liquid crystals and other soft materials. Here the use of surface topography is extended to the organization of liquid crystals of bent-core molecules, soft materials that, on the one hand, exhibit a rich, exciting, and intensely studied array of novel phases, but that, on the other hand, have proved very difficult to align. Among the most notorious in this regard are the polarization splay modulated (B7) phases, in which the symmetry-required preference for ferroelectric polarization to be locally bouquet-like or "splayed" is expressed. Filling space with splay of a single sign requires defects and in the B7 splay is accommodated in the form of periodic splay stripes spaced by defects and coupled to smectic layer undulations. Upon cooling from the isotropic phase this structure grows via a first order transition in the form of an exotic array of twisted filaments and focal conic defects that are influenced very little by classic alignment methods. By contrast, growth under conditions of confinement in rectangular topographic channels is found to produce completely new growth morphology, generating highly ordered periodic layering patterns. The resulting macroscopic order will be of great use in further exploration of the physical properties of bent-core phases and offers a route for application of difficult-to-align soft materials as are encountered in organic electronic and optical applications.

Polarographic studies of potassium isobutyl xanthate at a mercury electrode reveal that the product of an anodic reaction is strongly adsorbed at the mercury surface, as indicated by a prewave. The adsorbed film greatly affects the characteristics of the anodic wave of xanthate in an aqeous medium. The current of total wave is proportional to the concentration of xanthate from 0.32 to 1.6 mM.