A palladium catalyzed reductive aminocarbonylation of benzylic ammonium triflates with nitroarenes for the synthesis of phenylacetamides was developed. Using Pd(acac)2/DPPF catalyst system, a range ...of different substituted phenylacetamides were prepared in moderate to good yields from benzylic ammonium triflates and nitroarenes through Csp3−N bond cleavage. A variety of alkyl, aryl, and halide substituents on both substrates can be used, and many useful functional groups can be tolerated.
A novel iminoxyl radical-involved metal-free approach to vicinal oxyoximation and aminooximation of unactivated alkenes is developed. This method utilizes the dichotomous reactivity of the iminoxyl ...radical to furnish a general difunctionalization on alkenes using simple tert-butyl nitrite (TBN) as the iminoxyl radical initiator as well the carbon radical trap. By using this protocol, oxime featured 4,5-dihydroisoxazoles and cyclic nitrones were facilely prepared from β,γ- and γ,δ-unsaturated ketoximes, respectively.
Redundant collagen deposition at sites of healing dermal wounds results in hypertrophic scars. Adipose-derived stem cells (ADSCs) exhibit promise in a variety of anti-fibrosis applications by ...attenuating collagen deposition. The objective of this study was to explore the influence of an intralesional injection of ADSCs on hypertrophic scar formation by using an established rabbit ear model.
Twelve New Zealand albino rabbits were equally divided into three groups, and six identical punch defects were made on each ear. On postoperative day 14 when all wounds were completely re-epithelialized, the first group received an intralesional injection of ADSCs on their right ears and Dulbecco's modified Eagle's medium (DMEM) on their left ears as an internal control. Rabbits in the second group were injected with conditioned medium of the ADSCs (ADSCs-CM) on their right ears and DMEM on their left ears as an internal control. Right ears of the third group remained untreated, and left ears received DMEM. We quantified scar hypertrophy by measuring the scar elevation index (SEI) on postoperative days 14, 21, 28, and 35 with ultrasonography. Wounds were harvested 35 days later for histomorphometric and gene expression analysis.
Intralesional injections of ADSCs or ADSCs-CM both led to scars with a far more normal appearance and significantly decreased SEI (44.04 % and 32.48 %, respectively, both P <0.01) in the rabbit ears compared with their internal controls. Furthermore, we confirmed that collagen was organized more regularly and that there was a decreased expression of alpha-smooth muscle actin (α-SMA) and collagen type Ι in the ADSC- and ADSCs-CM-injected scars according to histomorphometric and real-time quantitative polymerase chain reaction analysis. There was no difference between DMEM-injected and untreated scars.
An intralesional injection of ADSCs reduces the formation of rabbit ear hypertrophic scars by decreasing the α-SMA and collagen type Ι gene expression and ameliorating collagen deposition and this may result in an effective and innovative anti-scarring therapy.
In this communication, a low-profile circularly polarized (CP) staircase curl antenna array with 2:1 impedance bandwidth and 50% axial ratio (AR) bandwidth is proposed for fifth-generation (5G) ...millimeter-wave (mmW) communications. It overcomes a vital drawback of complex multilayer structure of the wideband CP antenna array. By fully taking advantage of 3-D staircase layout, the curl element achieves 2:1 impedance bandwidth, 57.9% AR bandwidth, and a maximum gain of 7.4 dBic. Accordingly, benefiting from the tapered matching transformer, a single-layer full-corporate microstrip feeding network with 111.4% impedance bandwidth is constructed. For demonstration, an <inline-formula> <tex-math notation="LaTeX">8\times8 </tex-math></inline-formula> staircase curl antenna array is designed on three-layer PCB laminates. The proposed antenna array is measured with an impedance bandwidth of 76.9% (20.0-45.0 GHz) and an AR bandwidth of 53.6% (23.1-40.0 GHz), demonstrating a promising candidate to be used in 5G mmW communications.
In this letter, a compact ultrawideband (UWB) multiple-input-multiple-output (MIMO) antenna with a high isolation covering 2.4 GHz WLAN and 3.1-10.6 GHz UWB bands is presented. The proposed antenna ...is based on meandering monopoles; an ultrawide bandwidth is achieved by involving two inverted L-shape parasitic strips and two smaller L-shape stubs, and a high isolation is obtained by etching a slot at the center of the ground. The prototype is simulated, fabricated, and measured. A good agreement between the measured and simulated results shows that an ultrawide bandwidth and a high isolation are successfully achieved.
AIM:To investigate the impact of prognostic nutritional index(PNI)on the postoperative complications and long-term outcomes in gastric cancer patients undergoing total gastrectomy.METHODS:The data ...for 386 patients with gastric cancer were extracted and analyzed between January2003 and December 2008 in our center.The patients were divided into two groups according to the cutoff value of the PNI:those with a PNI≥46 and those with a PNI<46.Clinicopathological features were compared between the two groups and potential prognostic factors were analyzed.The relationship between postoperative complications and PNI was analyzed by logistic regression.The univariate and multivariate hazard ratios were calculated using the Cox proportional hazard model.RESULTS:The optimal cutoff value of the PNI was set at 46,and patients with a PNI≥46 and those with a PNI<46 were classified into PNI-high and PNI-low groups,respectively.Patients in the PNI-low group were more likely to have advanced tumor(T),node(N),and TNM stages than patients in the PNI-high group.The low PNI is an independent risk factor for the incidence of postoperative complications(OR=2.223).The 5-year overall survival(OS)rates were 54.1%and21.1%for patients with a PNI≥46 and those with a PNI<46,respectively.The OS rates were significantly lower in the PNI-low group than in the PNI-high group among patients with stagesⅡ(P=0.001)andⅢ(P<0.001)disease.CONCLUSION:The PNI is a simple and useful marker not only to identify patients at increased risk for postoperative complications,but also to predict long-term survival after total gastrectomy.The PNI should be included in the routine assessment of advanced gastric cancer patients.
The pandemic of coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), is a major challenge to health systems worldwide. Recently, numbers of ...epidemiological studies have illustrated that climate conditions and air pollutants are associated with the COVID-19 confirmed cases worldwide. Researches also suggested that the SARS-CoV-2 could be detected in fecal and wastewater samples. These findings provided the possibility of preventing and controlling the COVID-19 pandemic from an environmental perspective. With this review, the main purpose is to summarize the relationship between the atmospheric and wastewater environment and COVID-19. In terms of the atmospheric environment, the evidence of the relationship between atmospheric environment (climate factors and air pollution) and COVID-19 is growing, but currently available data and results are various. It is necessary to comprehensively analyze their associations to provide constructive suggestions in responding to the pandemic. Recently, large numbers of studies have shown the widespread presence of this virus in wastewater and the feasibility of wastewater surveillance when the pandemic is ongoing. Therefore, there is an urgent need to clarify the occurrence and implication of viruses in wastewater and to understand the potential of wastewater-based epidemiology of pandemic. Overall, environmental perspective-based COVID-19 studies can provide new insight into pandemic prevention and control, and minimizes the economic cost for COVID-19 in areas with a large outbreak or a low economic level.
Display omitted
•Climate factors are positively correlated with COIVD-19 cases in pandemic regions.•Increased exposure to air pollution lead to more COVID-19 cases.•Environmental perspective studies may be helpful in the pandemic prevention and control.•Wastewater surveillance can be used in tracking the spread of SARS-CoV-2 in the community.
The performance of a new type of concrete columns reinforced with multi-tied spiral transverse reinforcements called MTSTR columns has not yet been investigated and compared with other types of ...columns under eccentric loads. In this regard, three types of concrete columns, concrete-filled steel tube column (CFST), traditional concrete column (TCC) and MTSTR column were simulated in this study by nonlinear finite element (FE) method. The comparison between the load-moment interaction (P-M) diagrams of these columns revealed that the MTSTR column is the weakest among the three column types in the tension-controlled region of the P-M diagram. An oriented comprehensive parametric study was carried out in order to detect the reason and overcome the above-mentioned shortcoming. Obtained results showed that utilization of more spirals with small diameters and vertical spacing placed near the sides of the cross-section instead of a few spirals with the large diameter and vertical spacing located in the central part of the cross-section of the column improves considerably the eccentric bearing capacity of the MTSTR columns.
Objective
We aimed to explore the relationship among the duration of constipation at 30 days after thoracolumbar fracture surgery, self-efficacy, and anxiety or depression in patients with ...constipation after thoracolumbar fracture surgery.
Methods
In this descriptive correlational study, 108 patients with thoracolumbar fracture undergoing pedicle screw fixation surgery were recruited from January 2015 to May 2017 in our hospital. From the day of surgery, we conducted a 1-month follow-up investigation. We evaluated the pattern of defecation, stool consistency, and incidence of defecation-related problems using a structured interview. Clinical data were obtained using a patient intake form, and we applied the Health Behavior Self-Efficacy Scale (HBSES), and Hospital Anxiety and Depression Scale (HADS).
Results
Approximately 83.3% of patients experienced postoperative constipation, and most exhibited normal defecation by postoperative day 13. Self-efficacy and anxiety and depression were graded at a medium level in most patients. The average HBSES score was 74.39 ± 11.08, and the mean HADS score was 7.97 ± 4.08. The duration of postoperative constipation was negatively correlated with self-efficacy and positively associated with anxiety or depression.
Conclusions
Self-efficacy, anxiety, and depression are important sociopsychological factors associated with the duration of postoperative constipation.
Abstract
Stellar white-light flares are believed to play an essential role in the physical and chemical properties of the atmosphere of the surrounding exoplanets. Here we report an optical ...monitoring campaign on the nearby flaring system EI Cnc carried out by the Ground-based Wide Angle Camera (GWAC) and its dedicated follow-up telescope. A superflare, coming from the brighter component EI CncA, was detected and observed, in which four components are required to properly model the complex decay light curve. The lower limit of flare energy in the
R
− band is estimated to be 3.3 × 10
32
erg. A total of 27 flares are additionally detected from the GWAC archive data with a total duration of 290 hr. The inferred cumulative flare frequency distribution follows a quite shallow power-law function with a slope of
β
= − 0.50 ± 0.03 over the energy range between 10
30
and 10
33
erg, which reinforces the trend that stars cooler than M4 show enhanced superflare activity. The flares identified in EI Cnc enable us to extend the
τ
–
E
relationship previously established in the white-light superflares of solar-type stars down to an energy as low as ∼10
30
erg (i.e., by 3 orders):
τ
∝
E
0.42±0.02
, which suggests a common flare mechanism for stars with a type from M to solar-like and implies an invariant of
B
1/3
υ
A
in the white-light flares.
PDF
