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This article discusses the impact of short migration in Syria on neighboring countries. Since the begging of the civil war in Syria an exodus in large numbers has emerged. The turmoil and violence have caused mass migration to destinations both within the region and beyond. The article discusses the political, social and economic effects of these crises on the regional security in the Middle East and beyond. Refugee crisis provokes many difficulties in receiving countries and living conditions of refugees are often questionable due to difficult humanitarian situation. The article analyzes the challenge to the neighboring countries of Syria (Jordan, Turkey, Lebanon and Iraq), that has been hosted more than five million forced refugees according to UN last statistics. It is concluded that The Syrian refugee crisis remains one of the biggest problems facing the Middle East. It is more prone to more humanitarian and political problems, especially as it is a crisis of chaos, turmoil and protracted conflicts in the region.

Galvanizing reinforcing steel is one of the methods used to protect steel bars against corrosion. In 2001, a research program was started at the American University of Beirut (AUB), Beirut, Lebanon, to experimentally evaluate the effect of hot-dip galvanizing on the bond capacity of tension lap splices anchored in full-scale beam specimens designed to fail in bond splitting mode. The test results indicated that the use of galvanized bars had a negligible effect on bond strength of reinforcement in normal-strength concrete. Galvanizing, however, caused an average of 20% decrease in bond strength of reinforcement in high-strength concrete. The primary objective of the research reported in this paper was to find a solution to eliminate the bond reduction of galvanized bars in high-strength concrete. It was important to evaluate the potential positive effect of the addition of transverse reinforcement in the splice region. One hypothesis to be tested was that such transverse reinforcement would ensure uniform bond stress distribution over the entire splice length, thus mobilizing all bar lugs along the splice in the stress transfer mechanism between the bar and the surrounding concrete, and hence would lead to increasing the bond strength of galvanized bars. The second hypothesis to be checked was whether the aforementioned mechanism of mobilizing all bar lugs along the splice in the stress transfer mechanism would reduce the significant decrease in bond strength of galvanized bars relative to black bars in high-strength concrete. Eighteen full-scale beam specimens, designed to fail in bond-splitting mode, were tested in positive bending. Each beam was reinforced with bars spliced in a constant moment region at midspan. The main variables were bar size and the amount of transverse reinforcement in the splice region. The test results indicated that, whereas confinement increased the bond strength of galvanized bars and black bars, confinement did not have a significant positive effect on the bond strength of galvanized bars relative to black bars. [ABSTRACT FROM AUTHOR]

We propose a new method, based on a direct electron beam exposure of the SiO2 substrate surface, to create nucleation sites for silicon nano-crystals (Si-Ncs) grown via SiH4 chemical vapor deposition. Thus, control of the Si-Ncs in the growth plane can be obtained. Electron beam exposure has been used to induce local modifications of the chemical properties of the SiO2 layer, due to oxygen desorption. After this writing step, 5 nm diameter Si-Ncs have been deposited. Si-Ncs nucleate preferentially on the exposed area. Starting from experimental results and theoretical simulations, we demonstrate the possibility of achieving Si-Ncs spatial location in this way; these results are promising and open new paths for the realisation of single-electron components. [Copyright &y& Elsevier]

OBJECTIVE: To determine perceptions of parents about child abuse, and their impact on physical and emotional child abuse. MATERIALS AND METHODS: Two hundred parents attending three primary health care centers (PHCCs) in Riyadh serving National Guard employes and their families, were requested to participate in this survey. Data was collected by self administered questionnaire. Five main risk factors areas/domains were explored; three were parent related (personal factors, history of parents' childhood abuse, and parental attitude toward punishment), and two were family/community effects and factors specific to the child. SPSS was used for data entry and analysis. Descriptive analysis included computation of mean, median, mode, frequencies, and percentages; Chi-square test and t-test were used to test for statistical significance, and regression analysis performed to explore relationships between child abuse and various risk factors. RESULTS: Thirty-four percent of the parents reported a childhood history of physical abuse. Almost 18% of the parents used physical punishment. The risk factors associated significantly with child abuse were parents' history of physical abuse, young parent, witness to domestic violence, and poor self-control. Child-related factors included a child who is difficult to control or has attention deficit hyperactivity disorder (ADHD). Parents who did not own a house were more likely to use physical punishment. Abusive beliefs of parent as risk factors were: physical punishment as an effective educational tool for a noisy child; parents' assent to physical punishment for children; it is difficult to differentiate between physical punishment and child abuse; parents have the right to discipline their child as they deem necessary; and there is no need for a system for the prevention of child abuse. CONCLUSION: The causes of child abuse and neglect are complex. Though detecting child abuse may be difficult in primary care practice, many risk factors can be identified early. Parents' attitudes can be measured, and prevention initiatives, such as screening and counseling for parents of children at risk, can be developed and incorporated into primary care practice.

The present study aimed to synthesize and equate the mechanical properties and dentin interaction of two adhesives; experimental adhesive (EA) and 5 wt.% reduced graphene oxide rGO) containing adhesive. Scanning electron microscopy (SEM)-Energy-dispersive X-ray spectroscopy (EDX), Micro-Raman spectroscopy, push-out bond strength test, and Fourier Transform Infrared (FTIR) spectroscopy were employed to study nano-bond strength, degree of conversion (DC), and adhesive-dentin interaction. The EA was prepared, and rGO particles were added to produce two adhesive groups, EA-rGO-0% (control) and rGO-5%. The canals of sixty roots were shaped and prepared, and fiber posts were cemented. The specimens were further alienated into groups based on the root canal disinfection technique, including 2.5% sodium hypochlorite (NaOCl), Photodynamic therapy (PDT), and ER-CR-YSGG laser (ECYL). The rGO nanoparticles were flake-shaped, and EDX confirmed the presence of carbon (C). Micro-Raman spectroscopy revealed distinct peaks for graphene. Push-out bond strength test demonstrated highest values for the EA-rGO-0% group after NaOCl and PDT conditioning whereas, rGO-5% showed higher values after ECYL conditioning. EA-rGO-0% presented greater DC than rGO-5% adhesive. The rGO-5% adhesive demonstrated comparable push-out bond strength and rheological properties to the controls. The rGO-5% demonstrated acceptable DC (although lower than control group), appropriate dentin interaction, and resin tag establishment. [ABSTRACT FROM AUTHOR]

Hydrogen implanted silicon has been studied using high resolution X-ray scattering. Strain induced by implantation has been measured as a function of implantation dose. The dependence of strain with implanted dose shows different regimes starting from linear to quadratic and saturation. The observed strain is consistent with ab-initio and elasticity calculations. Strain rate changes can be associated to the predominant location of hydrogen in bond center location. [ABSTRACT FROM AUTHOR]

Benzo(a)pyrene (BaP) is a well-known carcinogen and enhances oxidative stress and apoptosis and also alters several molecular pathways. Curcumin is an active ingredient of Curcuma longa, and it has potent anti-inflammatory, antioxidant activity that defends cells from oxidative stress and cell death. The objectives of the present study were to explore the protective effects of curcumin against long-term administration of BaP induced disturbances in lungs of rats. Male rats were randomly divided into four groups: saline control, BaP only, BaP + curcumin, and curcumin only. Lung histopathology, electron microscopy, inflammatory cytokine release, antioxidant levels, apoptosis, and cell cycle were examined. Instillation of BaP significantly increased infiltration of inflammatory cells in alveolar space and inflammatory cytokine in blood. BaP induced lung tissue alterations including mild bronchitis, scant chronic inflammatory cell infiltrate in the wall of the respiratory bronchiole, and mild intra-alveolar haemorrhage. However, these alterations were found to be significantly less as mild inflammatory cell infiltrate in curcumin plus BaP treated group. Furthermore, electron microscopy results also showed necrotic changes and broken cell membrane of Type-II epithelial cell of alveoli in BaP group, which was reduced after adding curcumin treatment. In addition, we found BaP plus curcumin treatment effectively reduced inflammatory cytokines Tumour Necrosis Factor alpha (TNF-α), Interleukin 6 (IL-6), and C-reactive protein (CRP) levels in blood serum. Moreover, the levels of tunnel staining and p53 expression were significantly increased by BaP, whereas these changes were noticeably modulated after curcumin treatment. BaP also interferes in normal cell cycle, which was significantly improved with curcumin treatment. Overall, our findings suggest that curcumin attenuates BaP -induced lung injury, probably through inhibiting inflammation, oxidative stress and apoptosis in lung epithelial cells, and improving cell proliferation and antioxidants level. Thus, curcumin may be an alternative therapy for improving the outcomes of Benzo(a)pyrene-induced lung injury.

We present a detailed study of the growth of Ge nanocrystals (NCs) on SiO[sub 2] by chemical vapor deposition. A two-step process was developed. First, Si nuclei are deposited on SiO[sub 2] using SiH[sub 4] as a gaseous precursor. Then, Ge NCs grow selectively on the Si nuclei previously formed. The density of the Ge NCs is adjustable in between 10[sup 9] and 10[sup 12] cm[sup -2]. Their mean size varies between 5 and 50 nm. We have shown, combining grazing incidence x-ray diffraction and x-ray photoelectron spectroscopy, that pure Ge NCs are grown in a polycrystalline phase on a SiO[sub 2] surface. © 2003 American Institute of Physics. [ABSTRACT FROM AUTHOR]

The association between marital status and coronary artery disease (CAD) is supported by numerous epidemiological studies. While divorce may have an adverse effect on cardiac outcomes, the relationship between divorce and severe CAD is unclear. We conducted a multicenter, observational study of consecutive patients undergoing coronary angiography during the period between April 1, 2013, and March 30, 2014. Of 1,068 patients, 124 (12%) were divorced. Divorce was more frequent among women (27%) compared to men (6%). Most divorced patients had been divorced only once (49%), but a subset had been divorced 2 (38%) or ≥3 (12%) times. After adjusting for baseline differences, there was no significant association between divorce and severe CAD in men. In women, there was a significant adjusted association between divorce and severe MVD (OR 2.31 [1.16, 4.59]) or LMD (OR 5.91 [2.19, 15.99]). The modification of the association between divorce and severe CAD by gender was statistically significant for severe LMD (Pinteraction 0.0008) and marginally significant for CAD (Pinteraction 0.05). Among women, there was a significant adjusted association between number of divorces and severe CAD (OR 2.4 [95% CI 1.2, 4.5]), MVD (OR 2.0 [95% CI 1.4, 3.0]), and LMD (OR 3.4 [95% CI 1.9, 5.9]). In conclusion, divorce, particularly multiple divorces, is associated with severe CAD, MVD, and LMD in women but not in men.

Introduction: Acute coronary syndrome (ACS) is the leading cause of death in Saudi Arabia as elsewhere. Although, many studies found that South Asians had increased rates of ACS, others did not. The aim of the study is to explore the extent of difference between South Asians and Saudi presentation and risk factors of ACS patients. Materials and Methods: All patients who were diagnosed as having acute myocardial infarction (AMI) based on World Health Organization (WHO) criteria in 6 month period were included in the study. Results: A total of 190 patients confirmed ACS were included; 121 (63.70%) were Saudi, 50 (26.3%) were South Asians, and 19 (10.0%) were other Arab nationalities. The mean age was 53.9 (SD 14.6). Out of the total South Asians 82% had normal body mass index (BMI) ( P = 0.000). Saudi patients were the lowest of the three groups who smoked cigarette and/or shisha (26.6%; P = 0.000). 52.9% of Saudi patients were diabetics and 41.3% were hypertensive ( P = 0.004). More South Asians were presented with chest pain (94% vs 76%). Discussion: South Asians had a double rate of ACS incidence; they were younger, lower socio-economic status, more cigarette smokers, and less diabetics and hypertensive than other patients. An association between the apolipoprotein E (apoE) genotype with the incidence of ACS in young South Asian is proposed. Conclusion: South Asians had double rate of ACS incidence; they were younger, lower socio-economic status, more cigarette smokers, and less diabetics and hypertensive than other patients.

Background: Targeting epidermal growth factor receptors (EGFR) is an innovative approach to managing non-small cell lung cancer (NSCLC) which harbors EGFR mutation. However, the efficacy of these agents like erlotinib in patients without the mutation is not known. Methods: This systematic review included Phase III randomized clinical trials that compared single agent erlotinib to other management options in the setting of NSCLC with reported outcome data on patients with EGFR wild type (EGFRWT) tumors. Outcome data include overall survival (OS), progression free survival (PFS) and response rate (RR). Random effects meta-analysis was used to pool outcomes across studies. Results: Three studies met the inclusion criteria. These studies included a total of 2044 patients with outcome data on 674 patients with EGFRWT tumors (33%). Meta-analysis revealed a statistically significant improvement in OS with erlotinib (hazard ratio of 0.780; 95% confidence interval: 0.654-0.930, P = 0.006). Data were not available to perform PFS or RR analysis. The quality of this evidence is considered to be moderate to high. Conclusion: Our study revealed a significant benefit of erlotinib in patient with EGFRWT tumors compared with other approaches. These findings add another therapeutic option to patients generally considered difficult to treat.

Teaching Evidence Based Medicine (EBM) helps medical students to develop their decision making skills based on current best evidence, especially when it is taught in a clinical context. Few medical schools integrate Evidence Based Medicine into undergraduate curriculum, and those who do so, do it at the academic years only as a standalone (classroom) teaching but not at the clinical years. The College of Medicine at King Saud bin Abdulaziz University for Health Sciences was established in January 2004. The college adopted a four-year Problem Based Learning web-based curriculum. The objective of this paper is to present our experience in the integration of the EBM in the clinical phase of the medical curriculum. We teach EBM in 3 steps: first step is teaching EBM concepts and principles, second is teaching the appraisal and search skills, and the last step is teaching it in clinical rotations. Teaching EBM at clinical years consists of 4 student-centered tutorials. In conclusion, EBM may be taught in a systematic, patient centered approach at clinical rounds. This paper could serve as a model of Evidence Based Medicine integration into the clinical phase of a medical curriculum.

Objective and Background: Polycystic ovary syndrome (PCOS) is a complex condition and has been described in women who have polycystic ovaries as the underlying cause of hirsutism and chronic anovulation. Studies on PCOS in the Saudi population are very few. The aim of this study was to investigate the reproductive hormones levels in patients with PCOS. Effect of age and body mass index (BMI) on the hormonal findings was eliminated through a multivariate analysis. Materials and Methods: A comparative study was conducted on Saudi subjects attending the outpatient clinic of National Guard Hospital in Riyadh. A total of 62 cases with PCOS and 40 healthy Saudi women were included in this study. Physical evaluation and laboratory investigations were carried out. Blood luteinizing hormone (LH), follicle stimulating hormone (FSH), estradiol (E2), dehydroepiandrosterone sulfate (DHEA-SO 4 ), sex hormone-binding globulin (SHBG), total testosterone, prolactin, and progesterone were determined. To adjust for the potentially confounding effect of age and BMI, we carried out multivariate linear regression analyses for the association between each of the reproductive hormones and PCOS. Results: Serum levels of FSH, SHBG, and progesterone were significantly lower in PCOS compared to controls (respective P values 0.001, 0.001, and 0.002), while LH/FSH and testosterone levels were higher in PCOS cases than in controls (P = 0.008 and 0.003, respectively). When multivariate linear regression analyses were carried out, LH/FSH and total testosterone were positively correlated with the disease [95% confidence interval (CI) = 0.02-0.35 and 0.02-0.17, respectively], whereas FSH, SHBG, and progesterone were negatively correlated with the disease (95% CI = -0.06 to 0.001, -0.01 to 0.001, and -0.17 to -0.03, respectively), independent of age and BMI. Conclusion: Our study suggests that regardless of the age and weight factors, Saudi patients with PCOS have higher levels of LH/FSH and total testosterone; but have lower levels of FSH, SHBG, and progesterone compared to controls.

Background and Objectives: Hemodialysis catheters are commonly used when renal replacement therapy is initiated. These catheters have significant complications. Among "locking" solutions used in an attempt to decrease these complications is recombinant tissue plasminogen activator (rt-PA). This systematic review is to determine the efficacy of rt-PA versus heparin, the standard of care. Materials and Methods: A systematic review of randomized controlled trials studying rt-PA alone or rt-PA plus heparin versus heparin alone as locking agents for hemodialysis catheters, which included patients needed a temporary hemodialysis catheter for hemodialysis. We identified relevant trials through electronic databases and correspondence with experts. Two investigators independently reviewed potentially eligible trials and extracted data. Results: Three trials met the inclusion criteria. One trial reported an improved catheter malfunctioning in patients using rt-PA plus heparin to lock catheters (20.0%) versus heparin alone (34.8%). Another trial reported higher blood flow rate in hemodialysis catheters in patients who received rt-PA (231.6 ± 12.4 mL/min) compared with those who received heparin (206.9 mL/min). The third trial reported formation and weight of clots which were decreased by half in rt-PA group versus heparin group. Conclusions: In the few randomized trials that met our inclusion criteria, the use of rt-PA as a locking solution for hemodialysis catheters seems to be associated with fewer adverse events and catheter malfunctioning as compared with heparin. Our systematic review is limited by the few randomized trials addressing our question and the wide variety of outcome measures. Further prospective randomized trials are needed to confirm this conclusion.

A new technique is assessed in order to measure, at the wafer scale, direct bonding energies. It is derived from the standard Double Cantilever Beam (DCB) method and uses interferometry in confocal IR laser source microscopy to measure crack openings. Such a bonding energy measurement protocol has better accuracy compared to other techniques. This is due to a better confocal microscopy resolution and the high intensity of the laser source. The elastic energy stored in bent wafers is obtained by measuring the beam curvature. DCB deformation models are discussed from the short-range crack opening theory to long distance beam-bending theories. Comparison is made between models, experimental results, and FEM simulations. Finally, the bonding energy error during standard measurements is estimated. [ABSTRACT FROM AUTHOR]

Alkhurma hemorrhagic fever virus (genus Flavivirus, AHFV) was recently identified as the agent of a viral hemorrhagic fever in Saudi Arabia and characterized serologically and genetically as a variant genotype of Kyasanur Forest disease virus (KFDV). Since viral diagnosis and vaccine development may be hindered by genetic diversity, this study was intended to address AHFV genetic heterogeneity. Eleven strains isolated from hospitalized patients from 1994 to 1999 in Saudi Arabia were sequenced in the envelope, NS3, and NS5 genes. Homologous sequences were compared and used to look for patterns reflecting specific evolution associated with spatiality, temporality, infection pathway, and disease prognosis. Genetic analyses showed low diversity, which suggests a slow microevolution. Evaluation of divergence times showed that AHFV and KFDV ancestral lineage diverged 66–177 years ago, and the diversity observed within the studied AHFV strains reflected a 4- to 72-year period of evolution.

No Abstract.

Inflammatory bowel disease and its various treatments may affect the kidney in several ways. Recently, case reports have been published documenting the development of nephrotic syndrome after the treatment for inflammatory bowel disease with 5-aminosalicylic acid derivatives. We report a 50-year-old patient who was diagnosed with Crohn′s disease and was treated with mesalamine. The patient subsequently developed nephrotic syndrome and a renal biopsy showed minimal change disease. He was treated with losartan and rosuvastatin and showed improvement in his renal function and serum cholesterol level. This is the first reported case in Crohn′s disease although there have been six previous case reports of nephrotic syndrome following salicylic acid derivatives for ulcerative colitis.

We present our experience at the University of Illinois at Chicago (UIC) in deep brain stimulation (DBS) of the subthalamic nucleus (STN), describing our surgical technique, and reporting our clinical results, and morbidities. Twenty patients with advanced Parkinson’s disease (PD) who underwent bilateral STN-DBS were studied. Patients were assessed preoperatively and followed up for one year using the Unified Parkinson’s Disease Rating Scale (UPDRS) in “on” and “off” medication and “on” and “off” stimulation conditions. At one-year follow-up, we calculated significant improvement in all the motor aspects of PD (UPDRS III) and in activities of daily living (UPDRS II) in the “off” medication state. The “off” medication UPDRS improved by 49.3%, tremors improved by 81.6%, rigidity improved by 50.0%, and bradykinesia improved by 39.3%. The “off” medication UPDRS II scores improved by 73.8%. The Levodopa equivalent daily dose was reduced by 54.1%. The UPDRS IVa score (dyskinesia) was reduced by 65.1%. The UPDRS IVb score (motor fluctuation) was reduced by 48.6%. Deep brain stimulation of the STN improves the cardinal motor manifestations of the idiopathic PD. It also improves activities of daily living, and reduces medication-induced complications.

We investigate the recrystallization of thick phosphorus-implanted GeSn layers using 308 nm Ultraviolet Nanosecond Laser Annealing (UV-NLA). We identify the optimal annealing conditions leading to the reconstruction of Ge0.92Sn0.08 crystal amorphized by dopant implantation. The fully recrystallized GeSn layers present specific structures with localized tin and strain variations. Above the non-amorphized and unmelted Ge0.92Sn0.08 seed layer, a first highly tensile strained GeSn sublayer is formed, with a tin gradient from 2.5% up to 10.5%. Closer to the surface, a second sublayer consists of tin-enriched vertical structures in a Ge0.93Sn0.07 matrix. Laser annealing enables us to reverse the strain of the GeSn layer. The initial GeSn presents a compressive strain of −0.10%, while the recrystallized Ge0.93Sn0.07 matrix is tensile strained at 0.39%. UV-NLA presents the advantages of (i) local annealing that recrystallizes amorphized GeSn layers after implantation without excessive tin segregation and (ii) reversing the strain of epitaxial GeSn layers from compressive to tensile. Our results open up promising perspectives for the integration of GeSn mid-IR photonic devices. [ABSTRACT FROM AUTHOR]

The success of endodontic treatment relies on both apical and coronal sealing. To achieve a good three-dimensional seal, the removal of the smear layer becomes mandatory. This study aims to assess the difference in debris accumulation and smear layer formation while using automated root canal irrigation and conventional syringe needle irrigation. Single-rooted human mandibular premolar teeth (n = 30) which were indicated for orthodontic extractions were selected. An endodontic access cavity was prepared, and a glide path was created. Based on the irrigation protocol decided upon for the study, the teeth were randomly allocated into three study groups, namely Group 1, where the manual syringe needle irrigation method was adopted; Group 2, in which automated root canal irrigation was undertaken; and Group 3, in which teeth remained un-instrumented as it was considered the Control group. The teeth were decoronated at the cement-enamel junction (CEJ) and were subjected for scanning electron microscopy (SEM) examination. Debris and smear layers were viewed in 1000× magnification and scored. A statistically significant (p < 0.05) lower mean debris and smear layer score (p < 0.05) was observed in both study groups when compared with the control group. However, no significant difference (p > 0.05) in the debris and smear layer was observed between the manual syringe needle irrigation and automated irrigation, although automated irrigation devices can be a potential alternative. The present study concluded that the efficacy of smear layer removal remained the same with both automated irrigation and manual syringe irrigation. [ABSTRACT FROM AUTHOR]

The effect of H+ implantation and annealing of diamond (100) monocrystalline substrates has been studied by ToF-SIMS, cathodoluminescence, transmission spectroscopy and TEM. Blistering conditions suitable for the Smart Cut ™ technology have been identified in monocrystalline diamond, using two sets of hydrogen implantation and annealing. A first hydrogen implantation followed by a first annealing leads to amorphization of a buried layer without hydrogen exodiffusion. Blisters and exfoliations appear at the surface of the diamond samples, after a second hydrogen implantation inside the pre-amorphized diamond layer and a final annealing, as evidenced by TEM and optical microscopy. Demonstration of hydrogen-induced blistering is a major step to adapt the Smart Cut ™ process on diamond material. This process is compatible with wafer bonding before the second annealing and therefore open the way for thin diamond layer transfer on a bonded receiver wafer, still not achieved to date. [Display omitted] • A reliable blistering process of diamond is proposed. • Ion induced pre-amorphization is key to reliably achieve blistering of diamond • Thanks to pre-amorphization, diamond blistering is achieved at 1000 °C • The impact of the hydrogen dose is characterized by optical methods [ABSTRACT FROM AUTHOR]

This study aimed to conduct a compendious review of root canal morphology of "permanent mandibular teeth in different regions of Saudi Arabia" to obtain a large sample representing the total population. A detailed search through the databases Web of Science, Scopus, and PubMed was conducted following the PRISMA guidelines. The data were analyzed based on the following inclusion criteria: original full-length original articles that reported the variables of interest "(number of roots, number of canals, Vertucci's classification system and C-shaped canals or mid-mesial canals)" of the mandibular teeth and conducted on Saudi subjects. The retrieved data were presented as frequencies and percentages. The results revealed that 56.6% of mandibular central incisors had one canal and Vertucci type I (56.6%), while 57.4% of the mandibular lateral incisors had one canal, with Vertucci types I and III most frequent. In mandibular canines, 91.8% had one canal and 8.2% had two canals. Most of the mandibular first premolars had one root (86.6%), while almost all mandibular second premolars (91.5%) had one canal, and 96.9% had Vertucci type I configuration. Among the mandibular first molars, three and four canals were prevalent in 58.7% and 40.6%, respectively. The majority of mesial roots had Vertucci type IV (60.6%), and most of distal roots had Vertucci type I (72.2%). Most of the mandibular second molars had three canals (87.3%) and showed Vertucci type IV (39.4%) canals for mesial roots and Vertucci type I (95.6%) for distal roots. The C-shaped canals were seen in 8% of first premolars and 9.8% of second molars. The middle mesial canal was found in 4.2% and 0.4% of first and second molars, respectively. This review could represent "the population of Saudi Arabia as the included samples were combined from different regions of the country." Some variations were noticed within the same group of teeth from different regions. However, the overall results of combined samples were comparable to the other international studies. [ABSTRACT FROM AUTHOR]

Background: Stem cells play an important role in the success of regenerative endodontic procedures. They are affected by the presence of medicaments that are used before the induction of bleeding or the creation of a scaffold for endodontic regeneration. This study examines the effects of different intracanal medicaments on the viability and survival of dental pulp stem cells at different doses and over different exposure times. Methods: Dental pulp stem cells were cultured from healthy third molar teeth using the long-term explant culture method and characterized using flow cytometry and exposed to different concentrations of calcium hydroxide, doxycycline, potassium iodide, triamcinolone, and glutaraldehyde, each ranging from 0 (control) to 1000 µg/mL. Exposure times were 6, 24, and 48 h. Cell viability was measured using the MTT assay, and apoptosis was measured using the Annexin V-binding assay. Results: All medicaments significantly reduced cell viability at different concentrations over different exposure times. Calcium hydroxide and triamcinolone favored cell viability at higher concentrations during all exposure times compared to other medicaments. The apoptosis assay showed a significant increase in cell death on exposure to doxycycline, potassium iodide, and glutaraldehyde. Conclusion: The intracanal medicaments examined in our study affected the viability of dental pulp stem cells in a time and dose-dependent manner. They also adversely affected the survival of dental pulp stem cells. Further studies are needed to better understand the effect of prolonged exposure to medicaments according to clinical protocols and their effect on the stemness of dental pulp stem cells. [ABSTRACT FROM AUTHOR]

The impact of the Pre Amorphization by Ge Implantation (PAI) on Ni 0.9 Pt 0.1 silicide is studied. Reactions between a 10 nm thick Ni 0.9 Pt 0.1 film and Si (100) substrate are analyzed as a function of the induced amorphous-Si thicknesses. In view of being compatible with the integration constraint of the 28 nm CMOS technologies, the Ge implantation dose is fixed at a low level. The relative position of the amorphous-Si/crystalline-Si interface and the silicide growth front is defined for each sample. Then, in-situ XRD analyses, X-Ray Reflectometry (XRR) and Sheet resistance (Rs) measurements are achieved to provide a deep study of silicide growth kinetics and silicide properties. First, a clear relationship is established between the silicide growth rate and the amorphous-Si thickness. Secondly, an easier NiSi nucleation and a decrease of its resistivity is observed when NiSi nucleates at the θ-Ni 2 Si/a-Si interface. These observations are discussed considering the impact of the amorphous-Si layer on the driving force, the nucleation barrier, the lateral growth rate, and NiSi roughness. [Display omitted] • The effect of a Pre Amorphization-Implantation (PAI) using Ge on the Ni 0.9 Pt 0.1 silicides is studied using in-situ XRD, XRR and Rs. • A clear impact on the Ni 0.9 Pt 0.1 silicides formation and properties is found. • A relationship is established between the silicide growth rate and the amorphous thickness. • A decrease of the NiSi resistivity is observed when NiSi nucleates at the θ-Ni 2 Si/a-Si interface. • The a-Si layer impact on driving force, nucleation barrier, lateral growth rate, and NiSi roughness is discussed. [ABSTRACT FROM AUTHOR]

Background Increased inflammation has been well defined in coronavirus disease 2019 (COVID-19), while definitive pathways driving severe forms of this disease remain uncertain. Neutrophils are known to contribute to immunopathology in infections, inflammatory diseases, and acute respiratory distress syndrome, a primary cause of morbidity and mortality in COVID-19. Changes in neutrophil function in COVID-19 may give insight into disease pathogenesis and identify therapeutic targets. Methods Blood was obtained serially from critically ill COVID-19 patients for 11 days. Neutrophil extracellular trap formation (NETosis), oxidative burst, phagocytosis, and cytokine levels were assessed. Lung tissue was obtained immediately postmortem for immunostaining. PubMed searches for neutrophils, lung, and COVID-19 yielded 10 peer-reviewed research articles in English. Results Elevations in neutrophil-associated cytokines interleukin 8 (IL-8) and interleukin 6, and general inflammatory cytokines IFN-inducible protien-19, granulocyte macrophage colony-stimulating factor (GM-CSF), interleukin 1β, interleukin 10, and tumor necrosis factor, were identified both at first measurement and across hospitalization (P  < .0001). COVID-19 neutrophils had exaggerated oxidative burst (P  < .0001), NETosis (P  < .0001), and phagocytosis (P  < .0001) relative to controls. Increased NETosis correlated with leukocytosis and neutrophilia, and neutrophils and NETs were identified within airways and alveoli in lung parenchyma of 40% of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)–infected lungs available for examination (2 of 5). While elevations in IL-8 and absolute neutrophil count correlated with disease severity, plasma IL-8 levels alone correlated with death. Conclusions Literature to date demonstrates compelling evidence of increased neutrophils in the circulation and lungs of COVID-19 patients. Importantly, neutrophil quantity and activation correlates with severity of disease. Similarly, our data show that circulating neutrophils in COVID-19 exhibit an activated phenotype with enhanced NETosis and oxidative burst. [ABSTRACT FROM AUTHOR]

In this paper, a comparative study of C-, N- and Xe-based pre-amorphization implantation (PAI) processes is proposed. The impact of the use of such processes on the agglomeration resistance and physical properties of the final Ni(Pt)Si layer, as well as the formation mechanisms via solid-state reactions and electrical performances via the transfer length measurement (TLM) method, is evaluated. It is shown that although all species are able to increase the agglomeration temperature of Ni(Pt)Si layers (up to more than 100 °C), the underlying mechanisms are different. For C- and N-based PAI processes a strong chemical effect is observed, while for Xe-based processes the amorphization depth plays an important role. Consequently, the beneficial effect of stabilizing Ni(Pt)Si layers at high temperatures using C- and N-based PAI processes has to be balanced with an increased layer resistivity (up to 30%) combined with a strong deterioration of the associated specific contact resistivity (which is multiplied by almost a factor 10). In this sense, Xe-based PAI processes seem to be a better option as they could allow to combine both requirements. [Display omitted] • Ni(Pt)Si layer resistance to agglomeration is improved using either C, N or Xe-based PAI processes. • The phase sequence and final Ni(Pt)Si layer properties vary depending on the implanted species. • The underlying mechanisms depend on the implanted species type. • Using TLM structures, lower ρ c values are obtained for Xe-implanted samples compared to C-implanted ones. [ABSTRACT FROM AUTHOR]

In this article a review of low temperature (LT) (≤500 °C) process modules in view of 3-D sequential integration is presented. First, both the bottom device thermal stability and intermediate back end of line (iBEOL) versus thermal anneal and ns-laser anneal is determined, setting up the top device temperature fabrication process at 500 °C during a couple of hours. Then, the full LT process flow with process modules developed at 500 °C is exposed. Great progress and breakthrough for high performance (HP) digital stacked FETs has been made recently. Areas previously considered as potential showstoppers have been overcome: 1) efficient contamination containment for wafers with Cu/ultra low-k (ULK) iBEOL enabling their reintroduction in front end of line (FEOL) for top FET processing; 2) low-resistance poly-Si gate for the top FETs and solutions for improving gate-stack reliability; and 3) full LT raised source drain (RSD) epitaxy including surface preparation combined with SiCO 400 °C spacer and SPER junctions activation. Finally, the first functional nMOS and pMOS demonstration with a 500 °C thermal budget (TB) is highlighted. [ABSTRACT FROM AUTHOR]

Abstract: Photoluminescence (PL) properties of Er-doped silicon rich oxide thin films deposited on Si substrate by co-evaporation of silicon monoxide and Er under different atmospheres are investigated. The samples exhibit luminescence peak at 1.54μm which could be assigned to the recombination in intra-4f Er3+ transition. PL shows that this transition is highest when ammonia atmosphere is used during deposition followed by an annealing temperature at 850°C in 95% N2+5% H2 gas (forming gas). In fact, we believe that the presence of the N atoms around Er ions increases the intensity of the 1.54μm luminescence. [Copyright &y& Elsevier]

The Ni monosilicide alloyed with Pt is widely used as contact material in advanced microelectronics devices and a good knowledge of silicide formation kinetics is required for the process control. In this work, the nature, and the growth kinetics of the first silicide obtained during the solid-state reaction between the Ni 0.9 Pt 0.1 and the Si are studied for different pre amorphization implant (PAI) conditions as well as for a reference sample without PAI. Reactions between a 10 nm thick Ni 0.9 Pt 0.1 film and Si (100) substrate are analyzed after several rapid thermal anneals (RTA). The nature of the first silicide is determined by Fourier Transform of TEM images and by chemical TEM-EDX analyses. The silicide growth behavior is determined by measuring the silicide thickness by X ray reflectivity (XRR) after the partial reaction induced by RTAs at different temperatures and times. To determine the growth law, the linear parabolic model is first considered but a nonlinear reactive diffusion model must be developed to accurately reproduce the experimental results. From this model, the effective diffusion coefficient as well as its activation energy were determined for the three samples with PAI and the reference sample without PAI. The influence of the driving force on the nonlinear diffusion for thin films is proved, and the impact of the amorphous substrate on the kinetics parameters is quantified and compared to the literature. [Display omitted] [ABSTRACT FROM AUTHOR]

3D sequential integration enables the full use of the third dimension thanks to its unique contact density far above the possibilities of 3D packaging solutions. However, as the transistors are sequentially stacked over each other, the thermal budget allowed for the fabrication of the top transistor is limited by the maximal temperature accepted by the already made bottom one. It was previously described that a thermal budget of T > 500 °C is enough to degrade the bottom transistors performance. So the technological challenge is to develop low temperature routines for the fabrication of the top devices. For that, different processes have to be adapted, mainly the dopant activation step, where the T > 1000 °C spike annealing must be replaced. In this contribution, we present the feasibility to dope by solid phase epitaxial regrowth (SPER) at 450 °C thin Si films (22 nm) containing high dopant concentration of 5 × 10 20 at/cm 3 . For n- and p-type dopants, the 450 °C SPER rendered low sheet resistance values, as low as the ones obtained with the high temperature activation method. [ABSTRACT FROM AUTHOR]

Stem cells from human exfoliated deciduous teeth (SHEDs) are considered a type of mesenchymal stem cells (MSCs) because of their unique origin from the neural crest. SHEDs can self-renewal and multi-lineage differentiation with the ability to differentiate into odontoblasts, osteoblast, chondrocytes, neuronal cells, hepatocytes, adipocytes, etc. They are emerging as an ideal source of MSCs because of their easy availability and extraordinary cell number. Ascorbic acid, or vitamin C, has many cell-based applications, such as bone regeneration, osteoblastic differentiation, or extracellular matrix production. It also impacts stem cell plasticity and the ability to sustain pluripotent activity. In this study, we evaluate the effects of ascorbic acid on stemness, paracrine secretion, and differentiation into osteoblast, chondrocytes, and adipocytes. SHEDs displayed enhanced multifaceted activity, which may have applications in regenerative therapy. [ABSTRACT FROM AUTHOR]

Background: Stem cell therapy has become an advanced and state-of-the-art procedure to regenerate lost tissues of the human body. Cartilage repair is a challenging task in which stem cells find potential application. One of the important biologic modifiers that can cause chondrogenic differentiation of stem cells is taurine. However, taurine has not been investigated for its effects on dental pulp derived stem cell (DPSC) chondrogenic differentiation. Objective: The objective of the study was to investigate if taurine administration to DPSCs heralds chondrogenic differentiation as ascertained by expression of SOX9, COL2A1, ACAN, ELN, and COMP. The study also investigated if the differentiated cells synthesized glycosaminoglycans, a marker of cartilage formation. The study also aimed to assess proliferative activity of the cells after taurine administration by measuring the hTERT gene and protein expression. Materials and methods: DPSCs were obtained from a molecular biology laboratory and characterization of stem cell markers was done by flow cytometry. The cells were subjected to a MTT assay using various concentrations of taurine. Following this, hTERT gene and protein estimation was done in the control, telomerase inhibitor treated DPSC (TI-III), 10 μM taurine treated DPSC, and TI-III + 10 μM taurine treated DPSCs. A polymerase chain reaction was done to assess gene expression of SOX9, COL2A1, ACAN, ELN, and COMP genes and glycosaminoglycans were estimated in control cells, Induced DPSCs, induced and TI-III treated DPSCs, and 10 μM taurine treated DPSCs. Results: DPSCs expressed CD73, CD90, and CD105 and did not express CD34, CD45, and HLA-DR, which demonstrated that they were mesenchymal stem cells. The MTT assay revealed that various concentrations of taurine did not affect the cell viability of DPSCs. A concentration of 10 μM of taurine was used for further assays. With regard to the hTERT gene and protein expression, the taurine treated cells expressed the highest levels that were statistically significant compared to the other groups. Taurine was also found to restore hTERT expression in telomerase inhibitor treated cells. With regard to chondrogenesis related genes, taurine administration significantly increased the expression of SOX9, COL2A1, ACAN, and ELN genes in DPSCs and caused a significant increase in glycosaminoglycan production by the cells. Conclusions: Taurine can be regarded a biologic modifier that can significantly augment chondrogenic differentiation of DPSCs and can find potential applications in regenerative medicine in the area of cartilage regeneration. [ABSTRACT FROM AUTHOR]

The impact of dual Ge/C pre-amorphization implantation (PAI) processes on the Ni 0.9 Pt 0.1 (7 nm)/Si system phase sequence has been investigated by advanced X-ray diffraction techniques and transmission electron microscopy (TEM). Using a high carbon implantation dose, it is found that the expected development of Ni-rich phases is not observed: a thick amorphous Ni 1− x Pt x Si layer developed until Ni 0.9 Pt 0.1 full consumption, followed by the development of a thin crystalline Ni 1− x Pt x Si layer along the TiN interface. By increasing the temperature further, this last one abruptly thicken, creating the final silicide layer. An alternative model to grain boundary diffusion is discussed, accounting for the final distribution of the foreign species within the silicide layer. The use of Ge in dual Ge/C PAI processes is proposed to impact the growing mechanisms by alloying to fine-tune the carbon distribution in the substrate sub-surface. [Display omitted] • Suppression of the Ni-rich phases when introducing C in the substrate. • PAI processes using carbon straightened the final Ni 1-x Pt x Si layer texture. • PAI processes allow for more Pt incorporation in the final Ni 1-x Pt x Si layer. • In Ge/C PAI processes, the first Ge shot can help distribute C in the substrate. [ABSTRACT FROM AUTHOR]

BACKGROUND Acute respiratory distress syndrome (ARDS) due to coronavirus 2019 (COVID-19) can result in severe disease requiring mechanical ventilatory support. A subset of these patients, however, demonstrate refractory hypoxemia/hypercarbia requiring veno-venous extracorporeal membrane oxygenation (V-V ECMO) as adjunctive therapy. The primary goal of V-V ECMO is a "bridge" to recovery of native lung function; however, patients may progress to irreversible pulmonary damage requiring lung transplantation. MATERIAL AND METHODS We conducted a retrospective review of patients with refractory COVID-19 ARDS/pulmonary fibrosis that required a V-V ECMO bridge to lung transplantation at our institution from May 2021 to December 2022. Data for analysis included patient demographics, pre/post-transplantation course, and 1-year outcomes. RESULTS Nine patients (6 male, 3 female) with an average age of 44.6±12.1 years required V-V ECMO support for COVID-19 and subsequently underwent lung transplantation. The median number of ECMO days was 57 (IQR 53-78). At listing, these patients had a median lung allocation score (LAS) of 91.86 (IQR 89.05-92.13). The median hospital length-of-stay was 89 days (IQR 54-144) with the longest hospital stay at 255 days. All patients were discharged home and survived to 1-year post-transplant. CONCLUSIONS Our case series shows that patients with COVID-19 ARDS/pulmonary fibrosis had no meaningful difference in overall survival compared to our institution's overall 1-year lung transplant survival rate. Our results suggest that with careful selection and care, long-term lung transplantation outcomes can be equivalent for those requiring a bridge to transplantation with V-V ECMO support despite the severity of illness in the peri-transplant period.

Topic Importance: Acute pulmonary embolism (PE) is a common disease encountered by pulmonologists, cardiologists, and critical care physicians throughout the world. For patients with high-risk acute PE (defined by systemic hypotension) and intermediate high-risk acute PE (defined by the absence of systemic hypotension, but the presence of numerous other concerning clinical and imaging features), intensive care often is necessary. Initial management strategies should focus on optimization of right ventricle (RV) function while decisions about advanced interventions are being considered., Review Findings: We reviewed the existing literature of various vasoactive agents, IV fluids and diuretics, and pulmonary vasodilators in both animal models and human trials of acute PE. We also reviewed the potential complications of endotracheal intubation and positive pressure ventilation in acute PE. Finally, we reviewed the data of venoarterial extracorporeal membrane oxygenation use in acute PE. The above interventions are discussed in the context of the underlying pathophysiologic features of acute RV failure in acute PE with corresponding illustrations., Summary: Norepinephrine is a reasonable first choice for hemodynamic support with vasopressin as an adjunct. IV loop diuretics may be useful if evidence of RV dysfunction or volume overload is present. Fluids should be given only if concern exists for hypovolemia and absence of RV dilatation. Supplemental oxygen administration should be considered even without hypoxemia. Positive pressure ventilation should be avoided if possible. Venoarterial extracorporeal membrane oxygenation cannulation should be implemented early if ongoing deterioration occurs despite these interventions., Competing Interests: Financial/Nonfinancial Disclosures The authors have reported to CHEST the following: T. A. M. and T. M. F. disclose research support from Inari Health. None declared (W. C. M., L. S., M. F. O., B. D.)., (Published by Elsevier Inc.)

Aims: Evaluation of the effects of the latest root canal disinfectants i.e., Micro-bubble emulsion (MBE), Neodymium-doped yttrium aluminum perovskite (Nd: YAP), Emblica officinalis (E. officinalis) on the removal of smear layer (SL) and push out bond strength (PBS) of resin-based root canal sealer to the radicular dentin., Methods: The coronal portion of sixty single-rooted human mandibular premolar teeth was precisely sectioned at the cementoenamel junction. The canals were prepared to utilize ProTaper universal rotary files till F3. All the study specimens were divided into four groups based on the disinfection regime (n = 15) Group 1: 5.25% NaOCl, Group 2: MBE, Group 3: Nd: YAP laser and Group 4: E. officinalis extract. All the canals were then finally irrigated using 17% EDTA solution as a final disinfecting agent. SL removal assessment was performed on five samples from each group using a scanning electron microscope (SEM). Ten samples from each group were then filled with root canal filling material and the roots were sectioned. Push-out test and failure mode analysis were performed using the universal testing machine (UTM) and stereomicroscope respectively. The mean scores of PBS and SL removal were compared using a one-way analysis of variance (ANOVA) and Post Hoc Tukey's HSD test p = 0.05., Results: Group-2 (MBE + EDTA) coronal section (1.50 ± 0.23) exhibited the most effective eradication of SL from the canal space. The apical third of Group-1 (NaOCl+EDTA) (2.68 ± 0.82) samples demonstrated the least effective removal of SL from the radicular canal. The maximum score of PBS of AH plus sealer to the canal dentin was exhibited by the coronal section of Group-2 (MBE + EDTA) (9.55 ± 0.45 MPa) samples. However, the apical third of Group-1 (NaOCl+ EDTA) specimens (5.16 ± 0.32 MPa) demonstrated the minimum EBS., Conclusion: MBE+ EDTA displayed better smear layer removal and bond integrity of AH plus sealer to the root canal dentin. Nd: YAP+ EDTA laser and E.officinalis displayed comparable outcomes to that of control NaOCl+ EDTA., (Copyright © 2024. Published by Elsevier B.V.)

The use of intermittent hemodialysis (iHD), and continuous renal replacement therapy (CRRT), along with extracorporeal membrane oxygenation (ECMO) in patients with acute kidney injury (AKI) and end-stage renal disease (ESRD) is very common. In this technical report, we describe the methods to perform these dialytic therapies safely and effectively using the ECMO circuit in lieu of a separate dialysis catheter. Specifically, we describe in detail how to connect these kidney replacement therapy modalities to a Quadrox, Nautilus, and Cardiohelp HLS (combined oxygenator and pump) oxygenator. The dialysis (iHD or CRRT) inlet is attached to the post-oxygenators Luer-Lock, whereas the return is attached to the pre-oxygenator Luer-Lock, both with a dual lumen pigtail. We also discuss the technical aspects of performing plasmapheresis in conjunction with ECMO and iHD or CRRT. Finally, we highlight the fact that the reported technique does not require modifying the ECMO cannulas/tubing which helps maximize safety., Competing Interests: Disclosure: The authors have no conflicts of interest to report., (Copyright © 2023 The Author(s). Published by Wolters Kluwer Health, Inc. on behalf of the ASAIO.)

Objective: The aim of this ambispective cohort study was to examine the effect of instructional methods on dental students' performance in a preclinical endodontic course. Two cohorts of undergraduate students were included. The pre-pandemic (retrospective) cohort, which had been taught via traditional instruction (live lecture and live demonstration), and the pandemic (prospective) cohort group, which had been taught via a blended learning approach (online/video recorded lecture and video demonstration, combined with practical training in the simulation laboratory)., Methods: A total of 263 dental students' competencies and written exam results were reviewed, with 137 students from the traditional and 126 from the blended learning groups. Students' performances in the competency practical and written exams for both groups were compared. Additionally, a post-course survey was designed to explore the students' perceptions of blended learning and was sent to the blended learning cohort., Results: There was a statistically significant difference between both groups in students' weekly practical project scores. The average score for females was significantly higher than that of males. However, their practical competency exam scores were comparable. On the other hand, the written exam scores were significantly higher in the blended than in the traditional group, with females demonstrating significantly higher written exam scores compared to males (p < 0.001)., Conclusion: Blended learning is an effective teaching method for preclinical endodontic courses. It could be more useful than traditional learning methods for the course's theoretical content. Additionally, the students preferred to continue learning using this model., (© 2023 American Dental Education Association.)