The exact suppression of backscattering from rotationally symmetric objects requires dual symmetric materials where ε
= μ
. This prevents their design at many frequency bands, including the optical ...one, because magnetic materials are not available. Electromagnetically small non-magnetic spheres of large permittivity offer an alternative. They can be tailored to exhibit balanced electric and magnetic dipole polarizabilities a
= b
, which result in approximate zero backscattering. In this case, the effect is inherently narrowband. Here, we put forward a different alternative that allows broadband functionality: Wavelength-sized spheres made from low permittivity materials. The effect occurs in a parameter regime where approximate duality is met for all multipolar order a
≈ b
, in a weakly wavelength dependence fashion. In addition, and despite of the low permittivity, the overall scattering response of these spheres is still significant. Scattering patterns are shown to be highly directive across an octave spanning band. The effect is analytically and numerically shown using the Mie coefficients.
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•Frequency based Monte Carlo sensitivity of the harvestable power and vehicle dynamics.•A widely broadened harvestable power is obtainable terms of higher excitation amplitudes.•The ...harvestable energy highly correlated to the damping rate and the tire stiffness.•The harvestable power responded weakly to the stiffness and the body and wheel masses.
Regenerative shock absorbers (RSAs) have still not entered production lines despite the promising potentials in energy efficiency and emission reduction. Vibration energy harvesting from vehicle dampers has been replicating the dynamics of passive viscous dampers. An accurate frequency-based analysis of the harvestable energy and dynamics for vehicle suspensions under typical operating conditions is essentially needed for designing functional Vibratory Regenerative Dampers (VRDs). This paper proposes frequency-based parametrical bandwidth sensitivity analyses of both the vehicular suspension dynamics and energy harvesting potentiality in accordance with the Monte Carlo sensitivity simulations. This provides insights into which suspension parameter could highly broaden the harvestable power magnitude, which contributes positively to conceptualizing an efficient design of a wide broad-banded energy harvesting damper leading to improved harvesting efficiencies in different road conditions. The conducted sensitivity analysis included the change in both frequency and amplitude bandwidth of the dissipative damping power, body acceleration, dynamic tire load, and suspension deflection. During the sensitivity simulations, a 2-DOFs (degrees-of-freedom) quarter-car model is considered, being excited by harmonic excitations. The selected suspension parameters were normally randomized according to the Gaussian probability distribution based on their nominal values and a 30% SD (standard deviation) with respect to the uniformly randomized excitation frequency. The results inferred higher sensitivity change in the harvestable power bandwidth versus the excitation parameters, damping rate, and tire properties. Conversely, the harvestable power hardly broadened with respect to the body and wheel masses and the spring stiffness.
Hydrogel electrolytes are essential components of a plethora of functional devices due to their flexibility and high electronic and ionic conductivity. However, they suffer from poor water retention ...(dehydration) during operation. Consequently, the overall performance of the hydrogel-based devices is severely declined as a result of conductivity fading of the hydrogel with poor self-regeneration. To this end, the rational tailoring of hydrogel electrolytes with high conductivity, self-regeneration, non-flammability, anti-freezing ability, stability, and intrinsic redox activity is necessary to enable the fabrication of highly durable devices. Herein, we demonstrate the design and synthesis of highly ionic conductive LiBr@PVA-based electrolytes. Upon the use of the synthesized hydrogel electrolytes in supercapacitor devices, they revealed intrinsic redox activity with outstanding water retention capability and self-regeneration characteristics. The mechanism of regeneration and water retention is thoroughly investigated. Also, the devices showed an improved self-discharge potential (SDP) rate compared to those previously reported using polymeric electrolytes with redox additives. Moreover, the synthesized LiBr@PVA-based electrolytes exhibited high anti-freezing properties with stable electrochemical performance before and after regeneration. Our study provides a universal method to fabricate large-scale hydrogel electrolytes with unique properties and opens the door to fabricate high-performance solid state devices.
We report the rational tailoring of LiBr@PVA-based hydrogel electrolytes with high conductivity, self-regeneration, non-flammability, anti-freezing ability, stability, and intrinsic redox activity with exceptional self-discharge potential.
Background
Minimally invasive surgery is an expanding field of surgery that has replaced many open surgical techniques. Surgery remains a cornerstone in the treatment of esophageal cancer, yet it is ...still associated with significant morbidity and technical difficulties. Mediastinoscope-assisted esophagectomy is a promising technique that aims to decrease the surgical burden and enhance recovery.
Methods
PubMed, MEDLINE, and EMBASE databases were searched for publications on mediastinoscope-assisted esophagectomies for esophageal cancer. The primary endpoint was a postoperative anastomotic leak, while secondary endpoints were assessment of harvested lymph nodes (LNs), blood loss, chyle leak, hospital length of stay (LOS), operative (OR) time, pneumonia, wound infection, mortality, and microscopic positive margin (R1). The pooled event rate (PER) and pooled mean were calculated for binary and continuous outcomes respectively.
Results
Twenty-six out of the 2274 searched studies were included. The pooled event rate (PER) for anastomotic leak was 0.145 (0.1144; 0.1828). The PERs for chyle leak, recurrent laryngeal nerve injury/hoarseness, postoperative pneumonia, wound infection, early mortality, postoperative morbidity, and microscopically positive (R1) resection margins were 0.027, 0.185, 0.09, 0.083, 0.020, 0.378, and 0.037 respectively. The pooled means for blood loss, hospital stay, operative time, number of total harvested LNs, and number of harvested thoracic LNs were 159.209, 15.187, 311.116, 23.379, and 15.458 respectively.
Conclusions
Mediastinoscopic esophagectomy is a promising minimally invasive technique, avoiding thoracotomy, patient repositioning, and lung manipulation; thus allowing for shorter surgery, decreased blood loss, and decreased postoperative morbidity. It can also be reliable in terms of oncological safety and LN dissection.
The aim of this study was to assess the efficacy and safety of double-row transscleral cyclophotocoagulation in controlling intraocular pressure in patients with secondary angle closure glaucoma due ...to nanophthalmos, not being controlled by medical therapy.
A prospective case series study that included 13 eyes of 8 patients diagnosed with secondary angle closure glaucoma due to nanophthalmos at the Giza Eye Subspeciality Center, treated by 24 cyclodiode applications in a double-row technique. Success was defined as complete success by control of intraocular pressure <21 mm Hg without medication and qualified success in which control of pressure <21 mm Hg achieved with 1 or 2 medications.
The average reduction in intraocular pressure at 3 months was 57.3±20.14% and at 6 months 44.5±32%, with an average eye drop intake of 1.3±0.8 drops. There was a significant reduction of intraocular pressure at 6 months compared with the preprocedure pressure ( P =0.01). Complete success achieved in 3 eyes, pressure controlled without any medication, and qualified success in 9 eyes.
Transscleral cyclophotocoagulation is a safe and effective primary therapy for managing glaucoma in nanophthalmic eyes.
The ecological uniqueness of the Great Bitter Lake ecosystem makes its bacterial population interesting for investigation. Here, we present the first trial to evaluate the biosynthetic capacity of ...the bacterial population at the lake as a source of novel antimicrobials. We collected different samples from various locations throughout the lake including the oxic sediment, anoxic sediment, shore water, and off-shore water. We modified a molecular approach to compare and choose the samples with the highest bacterial biosynthetic capacity by quantifying the polyketide synthase gene clusters in their total community DNA. Furthermore, we screened the bacterial isolates recovered from these samples and their metabolic extracts for antimicrobial activity. We tried to tentatively investigate the identity of the active metabolites by PCR screening and LC–MS. The bacterial population in the oxic sediment had the highest biosynthetic capacity compared to other sample types. Four active Bacillus isolates were identified. The isolated Bacillus species were expected to produce numerous probable bioactive metabolites encoded by biosynthetic gene clusters related to the polyketide synthases (either individual or hybrid with non-ribosomal peptide synthetase), such as Bacillomycin D, Iturin A, Bacilosarcin B, Bacillcoumacin G and Macrolactin (N and G). These results suggest that the under-explored bacterial community of the Great Bitter Lake has a prospective biosynthetic capacity and can be a promising source for novel antibiotics.
Abstract Albuminuria has been considered the golden standard biomarker for diabetic kidney disease (DKD), but appears once significant kidney damage has already occurred. Angiopoietin-2 (Angpt-2) has ...been implicated in the development and progression of DKD in adults. We aimed to explore the association of serum Angpt-2 levels with DKD in children and adolescents with type 1 diabetes mellitus (T1DM) of short duration (3–5 years) and to evaluate the predictive power of serum Angpt-2 in the early detection of DKD prior to the microalbuminuric phase. The current cross-sectional study included 90 children divided into three age and sex-matched groups based on urinary albumin-to-creatinine ratio (UACR): microalbuminuric diabetic group ( n = 30), non-albuminuric diabetic group ( n = 30), and control group ( n = 30). All participants were subjected to anthropometric measurements, serum Angpt-2 and fasting lipid profile (total cholesterol, triglycerides, LDL-C, HDL-C, and Non-HDL-C) assessment. Glomerular filtration rate was estimated based on serum creatinine (eGFR-Cr). Higher serum Angpt-2 levels were detected in both diabetic groups compared to controls and in microalbuminuric compared to non-albuminuric diabetic group. There was no detected significant difference in eGFR-Cr values across the study groups. Serum Angpt-2 was positively correlated with triglycerides, LDL, Non-HDL-C, HbA1c, and UACR, while UACR, HbA1c, and Non-HDL-C were independent predictors for serum Angpt-2. Serum Angpt-2 at level of 137.4 ng/L could discriminate between microalbuminuric and non-albuminuric diabetic groups with AUC = 0.960 and at level of 115.95 ng/L could discriminate between the non-albuminuric diabetic group and controls with AUC = 0.976. Conclusion : Serum Angpt-2 is a promising potent biomarker for the detection of early stage of DKD in childhood T1DM before albuminuria emerges. What is Known? • Urine albumin-to-creatinine ratio (UACR) and glomerular filtration rate (GFR) are the golden standard but late biomarkers for DKD. • Angiopoietin-2 has been implicated in the development and progression of DKD in adults with diabetes, but has not been explored in T1DM children with DKD. What is New? • Higher serum angiopoietin-2 was detected in diabetic groups compared to controls and in microalbuminuric compared to non-albuminuric group. • Angiopoietin-2 correlated positively with triglycerides, LDL, Non-HDL-C, HbA1c, and UACR. • Serum angiopoietin-2 is a promising early diagnostic biomarker for DKD in children with T1DM.
This model attracted attention due to its importance as it emerge in the modeling of many physical systems. We present an approximate solution for the fourth-order nonlinear Lane–Emden–Fowler ...equation using two simple and powerful methods, the first one is the Adomian decomposition method and the second one is the quintic B-spline method (QBSM). We transform the differential equation into an integral equation to overcome the singularity at the origin. Moreover, we discuss the convergence and the uniqueness of the three types of the model using the Adomian decomposition method. Finally, We present tables and graphs to make a comparison between the two methods and the exact solutions to exhibit the accuracy and efficiency of the proposed methods.
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