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We present a proof of concept for tunable plasmon resonance frequencies in a core shell nano-architectured hybrid metal-semiconductor multilayer structure, with Ag as the active shell and ITO as the dielectric modulation media. Our method relies on the collective change in the dielectric function within the metal semiconductor interface to control the surface. Here we report fabrication and optical spectroscopy studies of large-area, nanostructured, hybrid silver and indium tin oxide (ITO) structures, with feature sizes below 100 nm and a controlled surface architecture. The optical and electrical properties of these core shell electrodes, including the surface plasmon frequency, can be tuned by suitably changing the order and thickness of the dielectric layers. By varying the dimensions of the nanopillars, the surface plasmon wavelength of the nanopillar Ag can be tuned from 650 to 690 nm. Adding layers of ITO to the structure further shifts the resonance wavelength toward the IR region and, depending on the sequence and thickness of the layers within the structure, we show that such structures can be applied in sensing devices including enhancing silicon as a photodetection material.  相似文献   
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1 Background

Peri‐implant soft tissue inflammatory parameters and crestal bone loss (CBL) among waterpipe smokers (WS) with and without type 2 diabetes mellitus (T2DM) remains uninvestigated. The aim of the present study was to assess peri‐implant soft tissue inflammatory parameters and CBL among WS and never smokers (NS) with and without T2DM.

2 Methods

Demographic data and information regarding duration of implants in function, daily frequency of smoking, duration and treatment of T2DM, and daily toothbrushing was collected using a questionnaire. Peri‐implant plaque index (PI), bleeding on probing (BOP), probing depth (PD) ≥4 mm, CBL, and hemoglobin A1c (HbA1c) levels were assessed in all individuals. Level of significance was set at 5%.

3 Results

Seventy‐nine male individuals (39 patients with T2DM [20 WS and 19 NS] and 40 systemically healthy individuals [21 WS smokers and 19 NS]) were included. The mean age was comparable among individuals in all groups. The mean HbA1c levels were significantly higher among patients with T2DM compared to controls (P < 0.01). Peri‐implant PI, BOP, PD, and CBL were comparable among WS and NS with T2DM. Among patients without T2DM, PI (P < 0.05), PD ≥4 mm (P < 0.05) and mesial and distal CBL (P < 0.05) were significantly higher in WS than NS. Among individuals without T2DM, BOP was significantly higher among NS (P < 0.05) than WS. In patients with T2DM, BOP was comparable among WS and NS.

4 Conclusions

Peri‐implant soft tissue inflammatory parameters and CBL were comparable among WS and NS with T2DM. Among individuals without T2DM, these parameters were worse among WS than NS.  相似文献   
106.
Biomass-derived porous carbon materials have drawn considerable attention due to their natural abundance and low cost. In this work, nitrogen enriched porous carbons (NRPCs) with large surface areas were designed and prepared from cottonseed hull via simultaneous carbonization and activation with a facile one-pot approach. The NRPCs were tunable in terms of pore structure, nitrogen content and morphology by adjusting the ratio of the carbon precursor (cottonseed hull), nitrogen source (urea), and activation agent (KOH). The as-synthesized NRPCs exhibited three-dimensional oriented and interlinked porous structure, high specific surface area (1160–2573 m2 g−1) and a high level of nitrogen-doping (6.02–10.7%). In a three electrode system, NRPCs prepared at 800 °C with the ratio (cottonseed hull : KOH : urea) of 1 : 1 : 2 (NRPC-112) showed a high specific capacitance of 340 F g−1 at a current density of 0.5 A g−1 and good rate capability (∼80% retention at a current density of 10 A g−1) with 6 M KOH as electrolyte. In a two electrode cell, NRPC-112 demonstrated a high specific capacitance of 304 F g−1 at 0.5 A g−1 and an excellent rate capacity (∼71% retention at current density of 10 A g−1) as well as excellent cycling stability (∼91% retention at 5 A g−1) after 5000 cycles. Furthermore, the NRPCs exhibited an extraordinary adsorption capacity up to 205 mg g−1 for emerging pollutant triclosan. The work provided a sustainable approach to prepare functional carbon materials from biomass-based resource for environment remediation and electrochemical applications.

Biomass derived nitrogen-enriched porous carbon materials from cottonseed hull for emerging pollutant triclosan removal and electrochemical application.  相似文献   
107.
In this article, we studied the interactions between Mg atom and Mg2+ ion and four nanostructures, including a nanocone, nanotube (4,0), nanosheet, and C60 nanocage, to obtain the cell voltages (V) for Mg-ion batteries (MIBs). Total energy, geometry optimization, frontier molecular orbital (FMO) and density of states (DOS) analyses have been performed using the ωB97XD level of theory and the 6-31G(d) basis set. The DFT calculations clarified that the changes in energy adsorption between Mg2+ ion and the nanostructures, Ead, are in the order tube > cone > sheet > cage. However, Vcell for the nanocone is the highest. The changes in Vcell of the MIBs are in the order cone > tube > sheet > cage. This study theoretically considers the possibilities of Mg as an anode in batteries due to its high Vcell values.

In this article, we studied the interactions between Mg atom and Mg2+ ion and four nanostructures, including a nanocone, nanotube (4,0), nanosheet, and C60 nanocage, to obtain the cell voltages (V) for Mg-ion batteries (MIBs).  相似文献   
108.
ObjectiveTo evaluate the clinical characteristics and outcomes of pregnant women with Covid-19.Materials and methodsThis case series study was performed to investigate demographic, clinical and obstetric characteristics of 26 pregnant women with COVID-19 referring to a university hospital of Kashan during the epidemic of COVID-19 (March to May 2020).ResultsThe mean gestational age of the patients at admission and delivery was 31.8 ± 5.2 and 36.3 ± 3.4 weeks, respectively. The most common symptoms were fever (96.2%) followed by dyspnea and cough (30.8%). The findings of lung CT scan showed abnormalities confirming the pneumonia in 22 patients (84.6%). Cesarean section was performed in 69.2% of the mothers. The most common maternal–fetal outcome was preterm delivery (38%). Two mothers were transferred to the ICU due to deterioration in clinical condition and they underwent mechanical ventilation without any maternal death. The most common neonatal outcomes were prematurity (38%) and low birth weight (34.6%). No cases of confirmed COVID-19 were observed in the neonates.ConclusionClinical manifestations and laboratory and radiographic findings in pregnant women with COVID-19 are similar to the general population. Common outcomes of pregnancy and delivery in mothers included increased rate of preterm delivery and cesarean section. The most prevalent neonatal outcomes included prematurity and LBW. Careful monitoring of pregnant women with COVID-19 is recommended.  相似文献   
109.

Objective

The purpose of our study was to describe the MR appearance of mucoid degeneration of the anterior cruciate ligament and to address its clinical significance.

Patients and methods

A database search of 2000 knee MRI examinations revealed 32 examinations (Chart 1) with reported mucoid degeneration of the anterior cruciate ligament.

Results

Of 32 examinations that met imaging criteria, all patients (100%) had different degrees of mucoid degeneration. Associated ganglia were seen in eight patients; located in the proximal ligament in four examinations (12.5%) and the distal ligament in two (6%) and involved the mid-portion of the ligament in two (6%).Intra-osseous cysts were noted distally in 15 examinations (47%), proximally in four (12.5%) and on both sides in six (19%). All our patients had accessible medical records; no clinical evidence of instability was reported.Four patients who underwent arthroscopy had an intact anterior cruciate ligament at that time.

Conclusion

Anterior cruciate ligament mucoid degeneration has specific MRI features and should not be misdiagnosed as partial or total tear, and typically not associated with ligament instability.  相似文献   
110.
ABSTRACT: Since the publication of our article [1], we have noticed some errors in the final published version, for which the corresponding author accepts full responsibility. Page references are to the final PDF version. Page 3: Results, second paragraph Lines 1-2: "BMI... 20.7 (5.02) kg/m2..." should read "BMI... 16.0 (3.0) kg/m2..." Lines 6-8: "According to the IOTF cut-offs, overweight and obesity prevalence was 33% (95% CI 31.1-35.3) and 24% (95% CI 22.4-26.2) respectively" should read "According to the IOTF cut-offs, overweight and obesity prevalence was 8.3% (95% CI 7.1-9.6) and 4.7% (95% CI 3.8-5.7) respectively" Page 4: Table 1 The values for mean and standard deviation (SD) for BMI (kg/m2) are revised. Page 4: Table 2 The values for mean BMI (SD) and overweight and obesity prevalence according to the IOTF cut-offs are revised. Page 5: Figure 2 The values for grade- and gender- specific mean BMI are revised. Page 6: Second paragraph Lines 1-8: "Prevalence of overweight by the IOTF cut-offs was twice the prevalence by the WHO 2007 reference (33% versus 17%) and prevalence of obesity by the IOTF cutoffs was three times higher than that calculated by the WHO 2007 reference (24% versus 7.5%). Using IOTF cut-offs for overweight and obesity in Pakistani schoolaged children would result in higher estimates than the WHO 2007 reference." should read "Prevalence of overweight by the IOTF cut-offs was half the prevalence by the WHO 2007 reference (8% versus 17%) and prevalence of obesity by the IOTF cutoffs was two-third of that calculated by the WHO 2007 reference (5% versus 7.5%). Using IOTF cut-offs for overweight and obesity in Pakistani schoolaged children would result in lower estimates than the WHO 2007 reference. A relatively lower overweight and obesity prevalence with use of the IOTF cut-offs as compared to the WHO reference had been reported elsewhere [2-3]." In present study, the estimates for overweight included obese children.  相似文献   
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