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In this work we designed, fabricated and assessed a p+/n/n+ structure which constitute the basis and the core part of the n-type silicon solar cells. The process of fabrication is based on the co-diffusion of pre-deposited phosphorus and boron. It consists of carrying out simultaneously in one single high temperature step the diffusion of both boron and phosphorus of the p+ emitter and pre-deposited n+- back surface field (BSF), respectively. The first step was the pre-formation of the n+-BSF in a POCl3 furnace system. After depositing the silicon nitride film onto the wafers rear side as a diffusion barrier to protect them from being boron doped, the wafers underwent an alkaline bath to etch the phosphorus layer of the front side. Onto this latter we used a boron source paper sheets to create a p+ emitter (preform source) simultaneously with n+-BSF drive-in step. This co-diffusion process was carried out at a temperature of 930 °C in a quartz tube devoted to this purpose. The resulting structure has a sheet resistance of 49 Ω/□ and 39 Ω/□ for emitter and BSF, respectively, corresponding to junction depths of 0.40 μm and 0.55 μm. The dopants surface concentrations are of 1.14 E20 atoms. cm−3 and 6.20 E19 atoms. cm−3 for emitter and BSF, respectively. This p+/n/n+ structure was used to fabricate solar cells after passivating the emitter and screen printing the front and rear side metallic contacts. A short circuit current density of 31.60 mA/cm2, an open circuit voltage of 555 mV and an efficiency of 10.70% was measured indicating that our non-optimized fabrication process and the resultant device is viable. [ABSTRACT FROM AUTHOR]

In Additive Manufacturing, wherein the construction of parts directly from 3D models is facilitated, a meticulous focus on enhancing the mechanical characteristics of these components becomes imperative. This study delves into the nuanced impact of the orientation of deposited layers on the mechanical properties of 3D printed Polylactic Acid (PLA) parts. Experimental testing, coupled with predictive modeling using Tsai–Hill and Tsai–Wu criteria, forms the crux of our investigation. The predicted ultimate strength from both criteria exhibits commendable agreement with the 3D printed specimens across a spectrum of orientation angles. Concurrently, Finite Element Simulations are meticulously executed to forecast mechanical behavior, taking into account the observed elasticity and plasticity in various orientations. Our observations reveal a significant augmentation in Young’s modulus and ductility/elongation—40% and 70%, respectively—when transitioning from θ = 0° to θ = 90°. Furthermore, the ultimate strength experiences a notable increase, leading to varied failure modes contingent upon θ. These findings underscore the pivotal role played by the orientation of printed layers in shaping the anisotropic behavior of 3D printed PLA parts, thereby integrating key process variables for optimization objectives. This study contributes valuable insights for professionals in the engineering, design, and manufacturing domains who seek to harness the advantages of 3D printing technology while ensuring that the mechanical integrity of 3D printed parts aligns with their functional requisites. It emphasizes the critical consideration of orientation as a design parameter in the pursuit of optimization objectives.

The SiN/SiO2 stack is widely used to passivate the surface of n-type monocrystalline silicon solar cells. In this work, we have undertaken a study to compare the stack layer obtained with SiO2 grown by both rapid thermal and chemical ways to passivate n-type monocrystalline silicon surface. By varying the plateau time and the plateau temperature of the rapid thermal oxidation, we determined the parameters to grow 10 nm thick oxide. Two-step nitric acid oxidation was used to grow 2 nm thick silicon oxide. Silicon nitride films with three refractive indices were used to produce the SiN/SiO2 stack. Regarding this parameter, the minority carrier lifetime measured by means of QSSPC revealed that the refractive index of 1.9 ensured the best passivation quality of silicon wafer surface. We also found that stacks with nitric acid oxidation showed definitely the best passivation quality. In addition to produce the most efficient passivation, this technique has the lowest thermal budget. [ABSTRACT FROM AUTHOR]

The salt tolerance of four accessions of Arabidopsis thaliana (COL (Columbia), NOK2, N1438 and N1380) was evaluated during germination by the capacity of seeds to germinate in the presence of 50 mM NaCl and to maintain adequate acid phosphatase activity. Our results show that saline conditions reduced the final germination percentage, speed of germination and delayed the germination processes of accessions NOK2, N1438 and N1380. In contrast, 100% of germination was found in COL under salt-stress conditions. In the presence of NaCl 50 mM, acid phosphatase activity increased in the first 24 h, the activity reaching the control level in germinating seeds of COL, but in the three other accessions NOK2, N1438 and N1380, acid phosphatase activity diminished under salt stress. These findings suggest that changes in the phosphatase enzymes might play an important role in the acclimation of COL seeds to the changing environmental conditions.

Introduction: Evidence regarding the potentiating effects of intravenous dexamethasone on peripheral regional anesthesia in children is sparse. The objective of the current study was to investigate the potentiating effect of intravenous dexamethasone upon pudendal block during surgical correction of hypospadias using Snodgrass technique., Methods: The study consisted of a monocentric, randomized controlled, double-blinded study. Patients were randomized to receive either intravenous dexamethasone 0.15 mg.kg - 1 (D group) or a control solution (C group). Both groups received standardized anesthesia including a preemptive pudendal block performed after the induction of anesthesia. The primary outcome was the proportion of patients needing rescue analgesia. Secondary outcomes were other pain outcomes over the first 24 postoperative hours., Results: Overall, 70 patients were included in the study. Age were 24 [24; 36] and 26 [24; 38] months in the D and C groups, respectively (p = 0.4). Durations of surgery were similar in both groups (60 [30; 60], p = 1). The proportion of patients requiring rescue analgesia was decreased in the D group (23% versus 49%, in D and C groups respectively, p = 0.02). The first administration of rescue analgesia was significantly delayed in the D group. Postoperative pain was improved in the D group between 6 and 24 h after surgery. Opioid requirements and the incidence of vomiting did not significantly differ between groups., Conclusion: Associating intravenous dexamethasone (0.15 mg.kg - 1 ) to pudendal block during hypospadias surgery improves pain control over the first postoperative day. Further studies are needed in order to confirm these results., Gov Identifier: NCT03902249. A., What Is Already Known: dexamethasone has been found to potentiate analgesia obtained with regional anesthesia in children. B. WHAT THIS ARTICLE ADDS: intravenous dexamethasone was found to improve analgesia with a preemptive pudendal block during hypospadias surgery. C. IMPLICATIONS FOR TRANSLATION: results of this study indicate that intravenous dexamethasone could be used as an adjunct to pudendal block., (© 2024. The Author(s).)

Background: the shock index (SI) defined by the ratio of systolic blood pressure to heart rate was demonstrated as a simple tool in the triage and orientation of severe trauma patients to trauma centers., Aim: To assess the prognostic value of the SI ≥ 1 in terms of mortality in severe trauma patients admitted to the emergency room., Methods: We performed a prospective, observational and descriptive study with the inclusion of severe trauma patients over the age of 18 years admitted to the Vital Emergency Room over a 21-month period. SI was calculated at admission: SI = heart rate / systolic blood pressure, a SI threshold value ≥1 was fixed to define two groups: SI<1 and SI≥1., Results: A total of 290 trauma patients were included, 231 (79%) had a SI<1, whereas 59 (21%) had an SI≥1. Mean age was 43.5 ± 18 years, 82% were male. There was a significant difference in hospital mortality at 7 days and at 30 days between the two groups respectively (group SI<1 vs group SI≥1): [12% vs 40%; p <0.001 and 15% vs 47%; p <0.001]. In multivariate analysis, SI≥1 appears as an independent factor of hospital mortality at 7 days [OR = 2.03; 95% CI = 1.3-3.3; p =0.001] and at 30 days [OR = 2.69; 95% CI = 1.4- 5; p =0.002]., Conclusion: In severe trauma patients admitted to the emergency department; a SI ≥1 represents a predictive factor of hospital mortality at 7 days and one month.

Introduction: The severity of cardiotropic agents overuse is related to the risk of cardiac and hemodynamic life-threatening situations. Toxicity is attributed to their narrow therapeutic spectrum and pharmacodynamic properties. The clinical presentation, however, remains polymorphic and represents a challenge for the emergency physician to relate accountability to the exact agent., Aim: To evaluate epidemiological, clinical and prognostic profile of patients visiting emergency department in whom iatrogeny secondary to cardiotropic use was diagnosed., Methods: This was a single-center prospective study over 12 months. We included successively all patients aged over 18 years in whom diagnosis of cardiotropic iatrogeny was made. Cardiotropic related drug-induced events were selected after collegial decision making processing. Prognosis was evaluated in terms of severity and mortality at day 30. Univariate analysis was conducted. P<0.05 was significant., Results: We enrolled 51 patients. Median age was 72 years with IQR (25,75) of (62,78). Sex ratio was 0.64. Twenty cases of misuse were identified (39%) with 51% of cases being related to the physician. Accountability of the adverse drug event (ADE) was 51%. The ADE was considered severe in 45% of cases and the death rate on day 30 was 12%. Drug classes were dominated by beta-blockers in 20 patients (39%) and anti-arrhythmic agents (Amiodarone ®) in 18 patients (35%). Beta-blockers were significantly the most incriminated in the occurrence of severe ADE. A double iatrogeny was found in 13 patients (25%). Misuse and physician-related ADE were found to be predictive of the severity of ADE in univariate analysis with respectively: For misuse:(OR brut=22, CI95%=[5.2;93.5] ; p<0.001) and for related physician ADE (OR brut = 3,7 ; CI95%=[1.1;12] ; P= 0.015). Predictive factors of mortality at day 30 in the univariate analysis were: Past renal failure : OR brut 5,8; CI95%[1,3-26,5]; p=0,015 ; misuse with OR brut=16.7, 95% CI=[1.9-143.5], p=0.002 and severe ADE with OR brut=15, 95% CI=[1.75-129], p=0.032., Conclusion: This study showed that ADE related to Cardiotropic agents are frequent and remain a serious condition especially in elderly. Betablockers agents were the mostly incriminated therapeutic class in the severity of the clinical condition by its hemodynamic repercussions responsible of a high rate of hospitalizations and mortality. Misuse and physician-related ADE were found to be predictive of the severity. Whereas, occurrence of severe ADE, misuse and past renal failure were predictive of mortality. Moreover, in 51% patients, ADE was preventable and related to the prescription of physician showing the main role of the preventability and the role of the prescriber in the genesis of this severe condition.

Background: Several studies showed a correlation between C-reactive protein and mortality in spontaneous intracerebral hemorrhage. However, the best time to measure C-reactive protein to assess prognosis is not yet clear. The purpose of this study was to determine if initial or H24-C-reactive protein is independently associated with 30-day mortality in intracerebral hemorrhage., Methods: This is a retrospective study done within years 2010-2015. All intracerebral hemorrhage cases with missing data or with autoimmune disease or neoplasm were excluded. Univariate and multivariate analyses were assessed for initial C-reactive protein, H24-C-reactive protein, and confounding factors., Results: Of 122 patients, 91 were selected. Only H24-C-reactive protein, hematoma volume, and infratentorial origin were independently associated with 30-day mortality in intracerebral hemorrhage. When adjusted with intracerebral hemorrhage score, H24-C-reactive protein with a cutoff value of 30 mg/L independently predicted 30-day mortality., Conclusions: This study suggests that H24-C-reactive protein may be a more reliable marker than initial C-reactive protein in the prediction of mortality in intracerebral hemorrhage. A large multicentric study is necessary to confirm the interest of including H24-C-reactive protein to a modified intracerebral hemorrhage score for the prediction of 30-day mortality., (Copyright © 2017 National Stroke Association. Published by Elsevier Inc. All rights reserved.)

Background: Two varieties of Origanum majorana (Canadian and Tunisian) were evaluated for their phenolic, flavonoid and tannin contents, individual phenolic compounds and antioxidant activities under NaCl constraint., Results: The results showed a significant variability in phenolic composition and antioxidant behavior between the two varieties under salt stress. The phenolic composition of methanolic extracts was determined by reversed-phase high-performance liquid chromatography. Amentoflavone was the predominant flavonoid compound; in addition, trans-2-hydrocinnamic acid became the major phenolic acid with salt treatment of the Tunisian variety. In the control, Canadian variety extract was characterized by high levels of gallic acid and amentoflavone. However, under 75 mmol L(-1) NaCl, gallic acid content doubled, whereas amentoflavone content was maintained in the Canadian variety. Stimulation of phenolic acid biosynthesis was observed in these two varieties under salt treatment despite the fact that shoots of the Tunisian variety showed higher antioxidant activities compared to those from the Canadian variety. Tunisian O. majorana might have developed tolerance to salinity and avoided tissue damage by activating enzymes involved in the galactosylation of quercetin into quercetin-3-galactoside and quercetin-3-rhamnoside., Conclusion: Our results confirmed the tolerance of Tunisian O. majorana plants., (Copyright © 2012 Society of Chemical Industry.)

O. majorana shoots were investigated for their essential oil (EO) composition. Two experiments were carried out; the first on hydroponic medium in a culture chamber and the second on inert sand in a greenhouse for 20 days. Plants were cultivated for 17 days in hydroponic medium supplemented with NaCl 100 mmol L⁻¹. The results showed that the O. majorana hydroponic medium offered higher essential oil yield than that from the greenhouse. The latter increased significantly in yield (by 50 %) under saline constraint while it did not change in the culture chamber. Under greenhouse conditions and in the absence of salt treatment, the major constituents were terpinen-4-ol and trans-sabinene hydrate. However, in the culture chamber, the major volatile components were cis-sabinene hydrate and terpinen-4-ol. In the presence of NaCl, new compounds appeared, such as eicosane, spathulenol, eugenol, and phenol. In addition, in the greenhouse, with or without salt, a very important change of trans-sabinene hydrate concentration in EO occurred, whereas in the culture chamber change appeared in cis-sabinene hydrate content.

Background: The effects of salt on the essential oil yield and fatty acid composition of aerial parts of two marjoram varieties were investigated. Plants with 6 leaves were treated with NaCl (75mM)., Results: Salt treatment led to a reduction in aerial part growth. Salinity increased the fatty acid content more significantly in Tunisian variety (TV) than in Canadian variety (CV). CV showed an increase in double-bond index (DBI) and a decrease in malondialdehyde content under salt stress, while the opposite was observed in TV. The DBI was mainly affected by a strong reduction in oleic and linoleic acids in TV, whereas a strong stimulation of linoleic acid in CV was observed. Salt decreased and increased the essential oil yield in TV and CV respectively. The main constituents of the essential oil of TV were trans-hydrate sabinene and terpinen-4-ol, which showed a significant decrease under salt stress. In contrast, the main constituents of the essential oil of CV were sabinene and trans-hydrate sabinene, which showed a significant decrease and increase respectively under salt stress., Conclusion: Marjoram oil is a rich source of many compounds such as essential oils and fatty acids, but the distribution of these compounds differed significantly between the two varieties studied., (Copyright © 2011 Society of Chemical Industry.)

Salinity inhibits plant growth due to osmotic and ionic effects. However, little is known about the impact of genotype and salinity on biochemical and molecular processes in the leafy vegetable lettuce. We report here evaluations of two lettuce types, Verte (NaCl tolerant) and Romaine (NaCl sensitive), under iso-osmotic 100 mM NaCl and 77 mM Na(2)SO(4) treatments. As compared to Romaine, NaCl-treated Verte displayed better growth, contained lower levels of inorganic cations in leaves, and possessed superior antioxidative capacity due to enhanced carotenoid and phenolics biosynthesis and more active antioxidative enzymes resulting in reduced membrane damage. Both genotypes had relatively similar growth patterns under Na(2)SO(4) treatment, but Romaine showed enhanced root lignification, greater malondialdehyde formation, and suppressed Fe-superoxide dismutase expression in roots as compared with Verte.

Potassium-sodium interaction was compared in two natural accessions of Arabidopsis thaliana, Columbia-0 and NOK2. Seedlings were grown in the presence of 0 or 50 mM NaCl and 0.1; 0.625 or 2.5 mM K(+). At the lowest K(+) concentration, salt treatment inhibited both K(+) uptake and growth. Increasing the K(+) availability did not modified salt response in Columbia-0, but restored nearly normal net K(+) uptake in NaCl condition and alleviated NaCl growth reduction in NOK2. The effect of K(+) and NaCl on transcript level of several K(+) and Na(+) transporters in both shoots and roots was assessed using semi-quantitative RT-PCR. The mRNA abundance of the NHX1 and SOS1 Na(+)/H(+) antiporters was significantly increased by 50 mM NaCl in the two accessions. NHX1, which is responsible for Na(+) sequestration into vacuoles, was more up-regulated in NOK2 leaves than in Columbia-0's in NaCl stress condition. AKT1, which is the major channel involved in K(+) absorption, was down-regulated in salt stress condition, but was not responding to K(+) treatments. Only in NOK2, SKOR and AKT2, which respectively control xylem and phloem K(+) transport, were markedly up-regulated by 2.5 mM K(+) in both roots and shoots, independently of NaCl. Phenotypic and gene expression analyses suggest that the relative salt tolerance of NOK2 is mainly due to a high ability to sequester Na(+) in the vacuole and to take up and transport K(+). Up-regulation of SKOR and AKT2 by K(+), and of NHX1 by NaCl could participate in determining this phenotype.

A 45 year old man presented with a swelling on the right side of his face of 12 months duration. Subsequent magnetic resonance imaging (MRI) scans revealed he did in fact have two discrete tumours of his right parotid gland. Following a superficial parotidectomy and dissection of the deep lobe, histopathology revealed both tumours to be pleomorphic adenomas. We discuss the clinicopathological findings and implications in contemporary surgical management of parotid neoplasms.