Raman Study of Novel Nanostructured WO3 Thin Films Grown by Spray Deposition.

The present communication reports on the effect of the sprayed solution volume variation (as a thickness variation element) on the detailed Raman spectroscopy for WO3 thin films with different thicknesses grown from precursor solutions with two different concentrations. Walls-like structured monoclinic WO3 thin films were obtained by the spray deposition method for further integration in gas sensors. A detailed analysis of the two series of samples shows that the increase in thickness strongly affects the films' morphology, while their crystalline structure is only slightly affected. The Raman analysis contributes to refining the structural feature clarifications. It was observed that, for 0.05 M precursor concentration series, thinner films (lower volume) show less intense peaks, indicating more defects and lower crystallinity, while thicker films (higher volume) exhibit sharper and more intense peaks, suggesting improved crystallinity and structural order. For higher precursor concentration 0.1 M series, films at higher precursor concentrations show overall more intense and sharper peaks across all thicknesses, indicating higher crystallinity and fewer defects. Differences in peak intensity and presence reflect variations in film morphology and structural properties due to increased precursor concentration. Further studies are ongoing.

A Prospective Study on the Progression, Recurrence, and Regression of Cervical Lesions: Assessing Various Screening Approaches.

(1) Background: The prediction of cervical lesion evolution is a challenge for clinicians. This prospective study aimed to determine and compare the predictive accuracy of cytology, HPV genotyping, and p16/Ki67 dual staining alone or in combination with personal risk factors in the prediction of progression, regression, or persistence of cervical lesions in human papillomavirus (HPV)-infected patients; (2) Methods: This prospective study included HPV-positive patients with or without cervical lesions who underwent follow-up in a private clinic. We calculated the predictive performance of individual tests (cervical cytology, HPV genotyping, CINtecPlus results, and clinical risk factors) or their combination in the prediction of cervical lesion progression, regression, and persistence; (3) Results: The highest predictive performance for the progression of cervical lesions was achieved by a model comprising a Pap smear suggestive of high-grade squamous intraepithelial lesion (HSIL), the presence of 16/18 HPV strains, a positive p16/Ki67 dual staining result along with the presence of at least three clinical risk factors, which had a sensitivity (Se) of 74.42%, a specificity of 97.92%, an area under the receiver operating curve (AUC) of 0.961, and an accuracy of 90.65%. The prediction of cervical lesion regression or persistence was modest when using individual or combined tests; (4) Conclusions: Multiple testing or new biomarkers should be used to improve HPV-positive patient surveillance, especially for cervical lesion regression or persistence prediction.

Prediction of Intrauterine Growth Restriction and Preeclampsia Using Machine Learning-Based Algorithms: A Prospective Study.

(1) Background: Prenatal care providers face a continuous challenge in screening for intrauterine growth restriction (IUGR) and preeclampsia (PE). In this study, we aimed to assess and compare the predictive accuracy of four machine learning algorithms in predicting the occurrence of PE, IUGR, and their associations in a group of singleton pregnancies; (2) Methods: This observational prospective study included 210 singleton pregnancies that underwent first trimester screenings at our institution. We computed the predictive performance of four machine learning-based methods, namely decision tree (DT), naïve Bayes (NB), support vector machine (SVM), and random forest (RF), by incorporating clinical and paraclinical data; (3) Results: The RF algorithm showed superior performance for the prediction of PE (accuracy: 96.3%), IUGR (accuracy: 95.9%), and its subtypes (early onset IUGR, accuracy: 96.2%, and late-onset IUGR, accuracy: 95.2%), as well as their association (accuracy: 95.1%). Both SVM and NB similarly predicted IUGR (accuracy: 95.3%), while SVM outperformed NB (accuracy: 95.8 vs. 94.7%) in predicting PE; (4) Conclusions: The integration of machine learning-based algorithms in the first-trimester screening of PE and IUGR could improve the overall detection rate of these disorders, but this hypothesis should be confirmed in larger cohorts of pregnant patients from various geographical areas.

Investigating the Association between Serum and Hematological Biomarkers and Neonatal Sepsis in Newborns with Premature Rupture of Membranes: A Retrospective Study.

(1) Background: Neonatal early-onset sepsis (EOS) is associated with important mortality and morbidity. The aims of this study were to evaluate the association between serum and hematological biomarkers with early onset neonatal sepsis in a cohort of patients with prolonged rupture of membranes (PROM) and to calculate their diagnostic accuracy. (2) Methods: A retrospective cohort study was conducted on 1355 newborns with PROM admitted between January 2017 and March 2020, who were divided into two groups: group A, with PROM ≥ 18 h, and group B, with ROM < 18 h. Both groups were further split into subgroups: proven sepsis, presumed sepsis, and no sepsis. Descriptive statistics, analysis of variance (ANOVA) and a Random Effects Generalized Least Squares (GLS) regression were used to evaluate the data. (3) Results: The statistically significant predictors of neonatal sepsis were the high white blood cell count from the first (p = 0.005) and third day (p = 0.028), and high C-reactive protein (CRP) values from the first day (p = 0.004). Procalcitonin (area under the curve-AUC = 0.78) and CRP (AUC = 0.76) measured on the first day had the best predictive performance for early-onset neonatal sepsis. (4) Conclusions: Our results outline the feasibility of using procalcitonin and CRP measured on the first day taken individually in order to increase the detection rate of early-onset neonatal sepsis, in the absence of positive blood culture.

Pregnancy Outcomes in Patients with Urosepsis and Uncomplicated Urinary Tract Infections-A Retrospective Study.

Background and Objectives: Urinary tract infections (UTIs) are an important cause of perinatal and maternal morbidity and mortality. The aim of this study was to describe and compare the main pregnancy outcomes among pregnant patients with complicated and uncomplicated UTIs; Materials and Methods: This retrospective study included 183 pregnant patients who were evaluated for uncomplicated UTIs and urosepsis in the Urology Department of 'C.I. Parhon' University Hospital, and who were followed up at a tertiary maternity hospital-'Cuza-voda' from Romania between January 2014 and October 2023. The control group (183 patients) was randomly selected from the patient's cohort who gave birth in the same time frame at the maternity hospital without urinary pathology. Clinical and paraclinical data were examined. Descriptive statistics and a conditional logistic regression model were used to analyze our data. Results: Our results indicated that patients with urosepsis had increased risk of premature rupture of membranes (aOR: 5.59, 95%CI: 2.02-15.40, p < 0.001) and preterm birth (aOR: 2.47, 95%CI: 1.15-5.33, p = 0.02). We could not demonstrate a statistically significant association between intrauterine growth restriction and pre-eclampsia with the studied urological pathologies. Conclusions: Careful UTI screening during pregnancy is needed for preventing maternal-fetal complications.

Managing Fetal Ovarian Cysts: Clinical Experience with a Rare Disorder.

Background and Objectives: Fetal ovarian cysts (FOCs) are a very rare pathology that can be associated with maternal-fetal and neonatal complications. The aim of this study was to assess the influence of ultrasound characteristics on FOC evolution and therapeutic management. Materials and Methods: We included cases admitted to our perinatal tertiary center between August 2016 and December 2022 with a prenatal or postnatal ultrasound evaluation indicative of FOC. We retrospectively analyzed the pre- and postnatal medical records, sonographic findings, operation protocols, and pathology reports. Results: This study investigated 20 cases of FOCs, of which 17 (85%) were diagnosed prenatally and 3 (15%) postnatally. The mean size of prenatally diagnosed ovarian cysts was 34.64 ± 12.53 mm for simple ovarian cysts and 55.16 ± 21.01 mm for complex ovarian cysts (p = 0.01). The simple FOCs ≤ 4 cm underwent resorption (n = 7, 70%) or size reduction (n = 3, 30%) without complications. Only 1 simple FOC greater than 4 cm reduced its size during follow-up, while 2 cases (66.6%) were complicated with ovarian torsion. Complex ovarian cysts diagnosed prenatally underwent resorption in only 1 case (25%), reduced in size in 1 case (25%), and were complicated with ovarian torsion in 2 cases (50%). Moreover, 2 simple (66.6%) and 1 complex (33.3%) fetal ovarian cysts were postnatally diagnosed. All of these simple ovarian cysts had a maximum diameter of ≤4 cm, and all of them underwent size reduction. The complex ovarian cyst of 4 cm underwent resorption during follow-up. Conclusions: Symptomatic neonatal ovarian cysts, as well as those that grow in size during sonographic follow-up, are in danger of ovarian torsion and should be operated on. Complex cysts and large cysts (with >4 cm diameter) could be followed up unless they become symptomatic or increase in dimensions during serial ultrasounds.

Pregnancy Outcomes, Immunophenotyping and Immunohistochemical Findings in a Cohort of Pregnant Patients with COVID-19-A Prospective Study.

(1) Background: SARS-CoV-2 infection during pregnancy could determine important maternal and fetal complications. We aimed to prospectively assess placental immunohistochemical changes, immunophenotyping alterations, and pregnancy outcomes in a cohort of patients with COVID-19; (2) Methods: 52 pregnant patients admitted to a tertiary maternity center between October 2020 and November 2021 were segregated into two equal groups, depending on the presence of SARS-CoV-2 infection. Blood samples, fragments of umbilical cord, amniotic membranes, and placental along with clinical data were collected. Descriptive statistics and a conditional logistic regression model were used for data analysis; (3) Results: Adverse pregnancy outcomes such as preterm labor and neonatal intensive care unit admission did not significantly differ between groups. The immunophenotyping analysis indicated that patients with moderate-severe forms of COVID-19 had a significantly reduced population of T lymphocytes, CD4+ T cells, CD8+ T cells (only numeric), CD4+/CD8+ index, B lymphocytes, and natural killer (NK) cells. Our immunohistochemistry analysis of tissue samples failed to demonstrate positivity for CD19, CD3, CD4, CD8, and CD56 markers; (4) Conclusions: Immunophenotyping analysis could be useful for risk stratification of pregnant patients, while further studies are needed to determine the extent of immunological decidual response in patients with various forms of COVID-19.

Nosocomial Infections Affecting Newborns with Abdominal Wall Defects.

Abdominal wall defects are serious birth defects, with long periods of hospitalization and significant costs to the medical system. Nosocomial infection (NI) may be an additional risk factor that aggravates the evolution of newborns with such malformations. METHODS: in order to analyze the factors that may lead to the occurrence of NI, we performed a retrospective study over a period of thirty-two years (1990-2021), in a tertiary children's hospital; 302 neonates with omphalocele and gastroschisis were eligible for the study. RESULTS: a total of 33.7 % patients were infected with one or more of species of bacteria or fungi. These species were Enterobacteriaceae, Pseudomonas aeruginosa and Acinetobacter spp., Staphylococcus spp., Enterococcus spp. or Candida spp., but the rate of NI showed a significant decrease between the 1990-2010 and 2011-2021 period (p = 0.04). The increase in the number of surgeries was associated with the increase in the number of NI both for omphalocele and gastroschisis; in the case of gastroschisis, the age of over 6 h at the time of surgery increased the risk of infection (p = 0.052, marginal statistical significance). Additionally, for gastroschisis, the risk of NI was 4.56 times higher in the presence of anemia (p < 0.01) and 2.17 times higher for the patients developing acute renal failure (p = 0.02), and a hospitalization period longer than 14 days was found to increase the risk of NI 3.46-fold (p < 0.01); more than 4 days of TPN was found to increase the NI risk 2.37-fold (p = 0.015). Using a logistic regression model for patients with omphalocele, we found an increased risk of NI for those in blood group 0 (OR = 3.8, p = 0.02), in patients with a length of hospitalization (LH) of ≥14 days (OR = 6.7, p < 0.01) and in the presence of anemia (OR = 2.5, p = 0.04); all three independent variables in our model contributed 38.7% to the risk of NI. CONCLUSION: although in the past 32 years we have seen transformational improvements in the outcome of abdominal wall defects, there are still many factors that require special attention for corrections.

Hematologic Risk Factors for the Development of Retinopathy of Prematurity-A Retrospective Study.

(1) Background: Retinopathy of prematurity (ROP) can cause severe visual impairment or even blindness. We aimed to assess the hematological risk factors that are associated with different stages of ROP in a cohort of preterm newborns, and to compare the clinical characteristics and therapeutic interventions between groups. (2) Methods: This retrospective study included 149 preterm newborns from a tertiary maternity hospital in Romania between January 2018 and December 2018, who were segregated into: Group 1 (with ROP, n = 59 patients), and Group 2 (without ROP, n = 90 patients). The patients that were affected by ROP were subsequently divided into the following subgroups: Subgroup 1 (Stage 1, n = 21), Subgroup 2 (Stage 2, n = 35), and Subgroup 3 (Stage 3, n = 25). The associations were analyzed using multivariate logistic regression and sensitivity analysis. (3) Results: Platelet mass indexes (PMI) that were determined in the first, seventh, and tenth days of life were significantly associated with Stage 1 ROP. PMI determined in the first day of life was also significantly associated with Stage 2 ROP. The sensitivity and specificity of these parameters were modest, ranging from 44 to 57%, and 59 to 63%. (4) Conclusions: PMI has a modest ability to predict the development of ROP.

Machine Learning Approaches for the Prediction of Hepatitis B and C Seropositivity.

(1) Background: The identification of patients at risk for hepatitis B and C viral infection is a challenge for the clinicians and public health specialists. The aim of this study was to evaluate and compare the predictive performances of four machine learning-based models for the prediction of HBV and HCV status. (2) Methods: This prospective cohort screening study evaluated adults from the North-Eastern and South-Eastern regions of Romania between January 2022 and November 2022 who underwent viral hepatitis screening in their family physician's offices. The patients' clinical characteristics were extracted from a structured survey and were included in four machine learning-based models: support vector machine (SVM), random forest (RF), naïve Bayes (NB), and K nearest neighbors (KNN), and their predictive performance was assessed. (3) Results: All evaluated models performed better when used to predict HCV status. The highest predictive performance was achieved by KNN algorithm (accuracy: 98.1%), followed by SVM and RF with equal accuracies (97.6%) and NB (95.7%). The predictive performance of these models was modest for HBV status, with accuracies ranging from 78.2% to 97.6%. (4) Conclusions: The machine learning-based models could be useful tools for HCV infection prediction and for the risk stratification process of adult patients who undergo a viral hepatitis screening program.

Predictive Performance of Machine Learning-Based Methods for the Prediction of Preeclampsia-A Prospective Study.

(1) Background: Preeclampsia (PE) prediction in the first trimester of pregnancy is a challenge for clinicians. The aim of this study was to evaluate and compare the predictive performances of machine learning-based models for the prediction of preeclampsia and its subtypes. (2) Methods: This prospective case-control study evaluated pregnancies that occurred in women who attended a tertiary maternity hospital in Romania between November 2019 and September 2022. The patients' clinical and paraclinical characteristics were evaluated in the first trimester and were included in four machine learning-based models: decision tree (DT), naïve Bayes (NB), support vector machine (SVM), and random forest (RF), and their predictive performance was assessed. (3) Results: Early-onset PE was best predicted by DT (accuracy: 94.1%) and SVM (accuracy: 91.2%) models, while NB (accuracy: 98.6%) and RF (accuracy: 92.8%) models had the highest performance when used to predict all types of PE. The predictive performance of these models was modest for moderate and severe types of PE, with accuracies ranging from 70.6% and 82.4%. (4) Conclusions: The machine learning-based models could be useful tools for EO-PE prediction and could differentiate patients who will develop PE as early as the first trimester of pregnancy.

Can Bioactive Food Substances Contribute to Cystic Fibrosis-Related Cardiovascular Disease Prevention?

Advances in cystic fibrosis (CF) care have significantly improved the quality of life and life expectancy of patients. Nutritional therapy based on a high-calorie, high-fat diet, antibiotics, as well as new therapies focused on CFTR modulators change the natural course of the disease. They do so by improving pulmonary function and growing BMI. However, the increased weight of such patients can lead to unwanted long-term cardiovascular effects. People with CF (pwCF) experience several cardiovascular risk factors. Such factors include a high-fat diet and increased dietary intake, altered lipid metabolism, a decrease in the level of fat-soluble antioxidants, heightened systemic inflammation, therapeutic interventions, and diabetes mellitus. PwCF must pay special attention to food and eating habits in order to maintain a nutritional status that is as close as possible to the proper physiological one. They also have to benefit from appropriate nutritional counseling, which is essential in the evolution and prognosis of the disease. Growing evidence collected in the last years shows that many bioactive food components, such as phytochemicals, polyunsaturated fatty acids, and antioxidants have favorable effects in the management of CF. An important positive effect is cardiovascular prevention. The possibility of preventing/reducing cardiovascular risk in CF patients enhances both quality of life and life expectancy in the long run.

Prediction of HELLP Syndrome Severity Using Machine Learning Algorithms-Results from a Retrospective Study.

(1) Background: HELLP (hemolysis, elevated liver enzymes, and low platelets) syndrome is a rare and life-threatening complication of preeclampsia. The aim of this study was to evaluate and compare the predictive performances of four machine learning-based models for the prediction of HELLP syndrome, and its subtypes according to the Mississippi classification; (2) Methods: This retrospective case-control study evaluated pregnancies that occurred in women who attended a tertiary maternity hospital in Romania between January 2007 and December 2021. The patients' clinical and paraclinical characteristics were included in four machine learning-based models: decision tree (DT), naïve Bayes (NB), k-nearest neighbors (KNN), and random forest (RF), and their predictive performance were assessed; (3) Results: Our results showed that HELLP syndrome was best predicted by RF (accuracy: 89.4%) and NB (accuracy: 86.9%) models, while DT (accuracy: 91%) and KNN (accuracy: 87.1%) models had the highest performance when used to predict class 1 HELLP syndrome. The predictive performance of these models was modest for class 2 and 3 of HELLP syndrome, with accuracies ranging from 65.2% and 83.8%; (4) Conclusions: The machine learning-based models could be useful tools for predicting HELLP syndrome, and its most severe form-class 1.

Development of a Harmonized Protocol for Measurement of Foliar Wash-off Parameters: First Results.

The foliar wash-off coefficient is a parameter used by environmental fate models to estimate the amount of chemical removed from leaf surfaces by rainfall. In the European Union it is used by FOCUS surface water models to estimate soil loadings following rainfall after leaf surfaces have been treated with plant protection products. Currently, a default value of 0.5/cm is assumed for this parameter, although there is provision to provide experimental data to replace this default. The European Food Safety Authority proposed to increase the default parameter value to 1.0/cm. This increases the need for experimental refinement studies. However, no guidance for a harmonized protocol exists to estimate this parameter. We describe the results of a ring-test conducted to start a process of developing a harmonized experimental protocol to measure the foliar wash-off parameters, conducted by several laboratories across Europe. The proposed design uses whole plants (rather than individual leaves) to retain as much realism as possible. The extent of wash-off is then determined by comparison of compound residues in two sets of plants (with and without a defined rainfall event) measured using a fully validated crop residue method. This initial ring test used tebuconazole (Folicur EW 250) sprayed at 100 g ai/ha onto tomato plants at BBCH25. Each laboratory measured the residues before and after a rainfall event of 20 mm/h for 1 h and calculated the percentage of wash-off from these data. There was good agreement across the eight participating laboratories with a mean percentage of wash-off of 66.8% and a 95% confidence interval of ±11.8%. Determination of robust wash-off parameters was therefore considered feasible using the proposed test design. Environ Toxicol Chem 2023;42:535-541. © 2022 SETAC.

Ganglioneuroma of the Bladder in Association with Neurofibromatosis Type 1.

Neurofibromatosis type 1 (NF1) is a genetic disease, with autosomal dominant transmission, related to pathogenic variant of the tumor suppressor gene NF1 (17q11.2), predisposing affected subjects to a variety of benign (neurofibromas and plexiform neurofibromas) and malignant tumors. The lack of the NF1-neurofibromin gene product can cause uncontrolled cell proliferation in the central or peripheral nervous system and multisystemic involvement, and so the disease includes a heterogeneous group of clinical manifestations. Ganglioneuromas are benign tumors developing from the neural crest cells of the autonomic nervous system, considered to be part of neuroblastic tumors. Bladder localization is extremely rare in adults, and only three such cases were reported in children so far. The aim of our study, in addition to a brief review of the literature of these pathologies, is to bring to your attention the case of a sixteen year old patient with a very rare association of NF1 and bladder ganglioneuroma, who presented at the hospital with gross hematuria. Since bladder ganglioneuroma is a rare pathological condition, the differential diagnosis is difficult and imaging investigations and pathological investigations are the ones that elucidate this disease. The clinical approach of the medical multidisciplinary team involved should help the patient in managing her medical and surgical situation.

Effects of Achieving Sustained Virologic Response after Direct-Acting Antiviral Agents on Long-Term Liver Fibrosis in Diabetics vs. in Non-Diabetic Patients with Chronic Hepatitis C Infection.

Because of the prevalence of HCV worldwide as well as its undiagnosed population due to a lack of screening, HCV can be considered a modern pandemic disease. In 2016, the World Health Organization (WHO) set goals for HCV's elimination that included a 65 percent reduction in mortality and an 80 percent reduction in newly infected cases by 2030. This study is a follow-up evaluation of 80 patients who received interferon-free treatment with direct-acting agents (DAA) for chronic HCV infection between the second half of 2017 and the end of 2018. They were assessed using a FibroMax test prior to DAA administration. Two pills/day of Ombitasvir 12.5 mg/Paritaprevir 75 mg/Ritonavir 50 mg and two pills/day of Dasabuvir 250 mg were given to the patients for 8 weeks. After treatment, all 80 patients in this study achieved an SVR (sustained virologic response), and the FibroMax test was performed three years later. Our study found that successfully treating HCV infection can play a significant role in reducing fibrosis in T2DM patients. In comparison to those of ActiTest and SteatoTest, FibroMax scores showed a significantly greater reduction in T2DM patients than in treatment-naive patients.

Novel Water-Based Paints for Composite Materials Used in Electromagnetic Shielding Applications.

The development of materials offering electromagnetic interference (EMI) shielding is of significant consideration, since this can help in expanding the lifetime of devices, electromagnetic compatibility, as well as the protection of biological systems. Conductive paints used widely today in electromagnetic interference (EMI) shielding applications are often based on organic solvents that can create safety issues due to the subsequent environment problems. This paper concerned the development of eco-friendly conductive water-based paints for use in EMI-shielding applications. Graphene nanoplatelets, polyaniline emeraldine (PANI) doped with poly(styrene sulfonic acid) (PSS) or HCl or HBr and poly(3,4-ethylenedioxythiophene) poly(styrene sulfonic acid) (PEDOT:PSS) in various ratios were employed in a water base for developing the paints. The target was to develop homogeneous water-based paint-like fluid mixtures easily applied onto surfaces using a paint brush, leading in homogeneous, uniform, opaque layers, draying fast in air at room temperature, and having quite good electrical conductivity that can offer efficient EMI-shielding performance. The results of this parametric trial indicated the optimum compositions leading in paints with optimized properties that can result in uniform, homogeneous, and conductive layers up to a thickness of over 500 µm without deformation and cracking, offering attenuation of up to 60 dBs of incoming GHz electromagnetic radiation. In addition, the structural and morphological characteristics of these paints were studied in detail.

Metabolic Impact of Diabetes Mellitus Type 2 in Hepatitis C Virus Infected Patients.

OBJECTIVE: Patients with chronic hepatitis C are subjected to a greater risk of cardiovascular disease and difficult to control diabetes mellitus type 2 (T2DM) comparatively to people that have never contracted Hepatitis C Virus (HCV). We aimed to investigate the impact of T2DM on HCV patients with the help of Fibromax test results compared to nonT2DM patients, and the metabolic differences between the 2 study groups. Our long term goals are to observe the long term impact of achieving systemic virusologic response (SVR) by means of Direct-Acting antivirals (DAA) between the 2 cohorts. RESEARCH DESIGN AND METHODS: We selected a lot of 200 patients with HCV that will undergo interferon-free DAA-based antiviral treatment for HCV and we used the results of the Fibromax Test to compare the biological parameters of T2DM and nonT2DM patients. RESULTS Among patients with T2DM compared to NonT2DM there is a significant correlation on Steatotest, NashTest, GGT, Glycemia, body weight, height and BMI. Test also showed that 15,5% of the test group had elevated glycemia, indicating the probability of developing diabetes in the future. CONCLUSIONS: Our results suggest that HCV patients that also have T2DM are subjected to a combined higher risk of accelerated steatosis development, steatohepatitis, added difficulty in controlling glycemic levels. All these previous elements combined with a prevalence for patients to be overweight have a negative metabolic impact. Eradication of HCV with the help of DAA is important in order to help improving the metabolic impact of diabetes on steatosis, steatohepatitis. An added benefit is better management of glycemic control by decreasing insulin use and eliminating one risk factor of T2DM.

Effect of Graphene Nanoplatelets on the Structure, the Morphology, and the Dielectric Behavior of Low-Density Polyethylene Nanocomposites.

The incorporation of graphene nanoplatelets (GnPs) within a polymer matrix can play an important role in the physical properties and the functionality of the composite material. Composites consisting of low-density polyethylene (LDPE) and GnPs of different concentrations were developed by mixing GnPs with a molten form of the polymeric matrix. The effect of the GnPs content on the morphological, structural, and electrical properties of the composites were investigated. As shown, graphene presence and its concentration significantly modified the polymer matrix properties, a behavior that can be employed for tailoring its applicability in electrical applications. It was found that the increase of the graphene platelets concentration seems to promote the formation of graphene agglomerates, air gaps, and inhomogeneities, while higher dielectric constant/lower dielectric losses can be achieved.

Specific detection of stable single nucleobase mismatch using SU-8 coated silicon nanowires platform.

Novel microarray platform for single nucleotide polymorphisms (SNPs) detection has been developed using silicon nanowires (SiNWs) as support and two different surface modification methods for attaining the necessary functional groups. Accordingly, we compared the detection specificity and stability over time of the probes printed on SiNWs modified with (3-aminopropyl)triethoxysilane (APTES) and glutaraldehyde (GAD), or coated with a simpler procedure using epoxy-based SU-8 photoresist. Scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDX) were used for comparative characterization of the unmodified and coated SiNWs. The hybridization efficiency was assessed by comprehensive statistical analysis of the acquired data from confocal fluorescence scanning of the manufactured biochips. The high detection specificity between the hybridized probes containing different mismatch types was demonstrated on SU-8 coating by one way ANOVA test (adjusted p value *** < .0001). The stability over time of the probes tethered on SiNWs coated with SU-8 was evaluated after 1, 4, 8 and 21 days of probe incubation, revealing values for coefficient of variation (CV) between 2.4% and 5.6%. The signal-to-both-standard-deviations ratio measured for SU-8 coated SiNWs platform was similar to the commercial support, while the APTES-GAD coated SiNWs exhibited the highest values.