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The advancement of renewable energy technology has been significantly aided by solar photovoltaics (PV). Since solar PV is a weather‐dependent source, it cannot be dispatched. To ensure that the solar PV system can harvest the maximum amount of electricity for the available irradiance level, maximum power point tracking (MPPT) algorithms are used. For standalone low‐voltage DC (LVDC) microgrids to utilize the energy storage system as efficiently as possible, maximum power extraction is essential. The sensed PV voltage and current are essential for these MPPT algorithms to ensure that the maximum power point of the panel is captured. This work proposes an effective fault‐tolerant control (FTC) scheme for the solar PV subsystem in the LVDC microgrid that can seamlessly extract the maximum power despite the PV voltage sensor being faulty. The proposed FTC scheme uses a sliding mode observer (SMO)‐based method to detect and isolate PV voltage sensor faults in the standalone LVDC microgrid. The efficacy of the proposed FTC is assessed in a range of circumstances involving load disturbance, irradiance change, and various sensor fault scenarios. The performance of the proposed FTC is validated using experimental analysis on the LVDC microgrid testbed and MATLAB simulations. Given a faulty PV voltage sensor, at a given operating condition of the microgrid, the proposed FTC scheme is successful in reducing the additional power burden on the battery storage by at least two times. Consequently, the additional discharge in terms of SoC is also seen to be decreased by at least 9%. The proposed FTC technique outperforms the popular MPPT approaches for solar PV in terms of PV voltage sensor fault tolerance in the microgrid. [ABSTRACT FROM AUTHOR]

Herein, we developed an efficient approach to access biologically relevant 2‐aminoquinolines and 1‐aminoisoquinolines from readily available N‐sulfonyl‐1,2,3‐triazoles and 2‐quinolones or 1‐isoquinolones. This transformation involves the selective O−H insertion of these derivatives onto the in situ generated Rh‐azavinyl carbenes (Rh‐AVC) followed by rearrangement. The reaction proceeds smoothly under operationally simple conditions and the protocol was found to be scalable. [ABSTRACT FROM AUTHOR]

Background: Glottic insufficiency, or glottic gap as it is commonly called, is a common cause of dysphonia, producing symptoms of soft voice, decreased projection, and vocal fatigue. The etiology of glottic gap can occur from issues related to muscle atrophy, neurologic impairment, structural abnormalities, and trauma related causes. Treatment of glottic gap can include surgical and behavioral therapies or a combination of the two. When surgery is chosen, closure of the glottic gap is the primary goal. Options for surgical management include injection medialization, thyroplasty, and other methods of medializing the vocal folds. Methods: This manuscript reviews the current literature regarding the options for treatment of glottic gap. Discussion: This manuscript discusses options for treatment of glottic gap, including the indications for temporary and permanent treatment modalities; the differences between the available materials for injection medialization laryngoplasty and how they affect the vibratory function of the vocal folds and vocal outcome; and the evidence that supports an algorithm for treatment of glottic gap. Level of Evidence: 3a—Systematic review of case–control studies. [ABSTRACT FROM AUTHOR]

Background: Hepatocellular carcinoma (HCC) detection with B-mode and contrast-enhanced ultrasound (CUS) imaging often varies between subjects, especially in patients with background cirrhosis. Various factors contribute to this variability, including the tumor blood flow, tumor size, internal echoes, and its location in livers with diffuse fibro-cirrhotic changes. Objective: Towards improving lesion detection, this study evaluates a vasodilator, hydralazine, to enhance the visibility of HCC by reducing its blood flow relative to the surrounding liver tissue. Methods: HCC were analyzed for tumor visibility measured for B-mode, CUS, and hydralazine-augmented-contrast ultrasound (HyCUS) in an autochthonous HCC rat model. 21 tumors from 12 rats were studied. B-mode and CUS images were acquired before hydralazine injection. Rats received an intravenous hydralazine injection of 5 mg/kg,then images were acquired 20 min later. Four rats were used as controls. The difference in echo intensity of the lesion and the surrounding tissue was used to determine the visibility index (VI). Results: The visibility index for HCC was found to be significantly improved with the use of HyCUS imaging compared to traditional B-mode and CUS imaging. The visibility index for HCC was 16.5 ± 2.8 for HyCUS, compared to 5.3 ± 4.8 for B-mode and 4.1 ± 3.8 for CUS. The differences between HyCUS and the other imaging modalities were statistically significant, with p-values of 0.001 and 0.02, respectively. Additionally, when compared to control cases, HyCUS showed higher discrimination of HCC (VI = 6.4 ± 1.2) with a p-value of 0.003, while B-mode (VI = 6.7 ± 1.4,p = 0.5) and CUS (VI = 6.4 ± 1.2,p = 0.3) showed lower discrimination. Conclusion: Vascular blood flow modulation by hydralazine enhances the visibility of HCC. HyCUS offers a potential problem-solving method for detecting HCC when B-mode and CUS are unsuccessful, especially with background fibro-cirrhotic liver disease. Future evaluation of the approach in humans will determine its translatability for clinical applications. [ABSTRACT FROM AUTHOR]

Objective: Concerns have been raised regarding the impact of time‐restricted eating (TRE) on sex hormones in females. This study examined how TRE affects sex steroids in premenopausal and postmenopausal females. Methods: This is a secondary analysis of an 8‐week TRE study (4‐ to 6‐hour eating window) conducted in adults with obesity. Men and perimenopausal females were excluded. Females were classified into two groups based on menstrual status: premenopausal (n = 12) or postmenopausal (n = 11). Results: After 8 weeks, body weight decreased in premenopausal females (−3% ± 2%) and postmenopausal females (−4% ± 2%) (main effect of time, p < 0.001), with no difference between groups (no group × time interaction). Circulating levels of testosterone, androstenedione, and sex hormone binding globulin (SHBG) did not change in either group (no group × time interaction). Dehydroepiandrosterone (DHEA) concentrations decreased (p < 0.05) in premenopausal (−14% ± 32%) and postmenopausal females (−13% ± 34%; main effect of time, p = 0.03), with no difference between groups. Estradiol, estrone, and progesterone were measured only in postmenopausal females, and they remained unchanged. Conclusions: In premenopausal females, androgens and SHBG remained unchanged during TRE, whereas DHEA decreased. In postmenopausal females, estrogens, progesterone, androgens, and SHBG did not change, but DHEA was reduced. [ABSTRACT FROM AUTHOR]

In view of the inherent limitations associated with performing dynamic contrast enhanced‐magnetic resonance imaging (DCE‐MRI) in clinical settings, current study was designed to provide a proof of principle that Doppler sonography and DCE‐MRI derived perfusion parameters yield similar hemodynamic information from metastatic lymph nodes in squamous cell carcinomas of head and neck (HNSCCs). Strong positive correlations between volume fraction of plasma space in tissues (Vp) and blood volume (r = 0.72, p = 0.02) and between Vp and %area perfused (r = 0.65, p = 0.04) were observed. Additionally, a moderate positive correlation trending towards significance was obtained between volume transfer constant (Ktrans) and %area perfused (r = 0.49, p = 0.09). [ABSTRACT FROM AUTHOR]

Herein, we developed two distinct pyridine N‐oxide directed C−H activation protocols to achieve [4+1] annulation and alkoxylation of benzamide derivatives by merging Co‐catalysis with visible‐light photoredox catalysis. The protocols deliver the respective products in good yields under facile conditions at room temperature. The use of an inexpensive photocatalyst coupled with molecular oxygen bypassing the need of stoichiometric oxidants forms the chief highlight of the work. The protocols are scalable and the products could be further modified. Additionally, preliminary studies were carried out to probe the reaction mechanism. [ABSTRACT FROM AUTHOR]

Compared to halides Cs2HfX6 (X = Cl, Br, I) with a vacancy‐ordered cubic double perovskite structure, the halide Cs2HfF6 (CHF), with a hexagonal Bravais lattice, possesses a higher mass density and chemical stability for radiation detection. Luminescence properties and energy transfer mechanisms of rare‐earths‐doped CHF materials are studied here. The structure of CHF is identified as a new type of vacancy‐ordered hexagonal perovskite, with the same type of building blocks of the double perovskite but stacked with single layers. Density‐functional theory calculations reveal a large bandgap of CHF. A broad emission is observed from the pristine CHF host, which is suggested to be associated with self‐trapped excitons (STEs). A series of rare‐earths‐doped materials are designed utilizing the STE emissions, and efficient energy transfers from STEs and Tb3+ to Eu3+ are achieved for tunable emissions. The codoped material shows stable emission under X‐ray irradiation, with 10.2% reduction from its initial emission intensity, associated with possible structural evolution by radiation‐induced deformation of the soft host. The radiation responses of singly and codoped materials are evaluated, and the codoped material is found to be more sensitive to the radiation energy than the singly doped or pristine CHF for radiation detection. [ABSTRACT FROM AUTHOR]

We hereby disclose, a visible light mediated addition of sulfenyl radicals to trialkyl phosphites to access functionalized phosphorothioates. The use of cheap and readily available Eosin Y as a photocatalyst under mild energy efficient conditions bypassing the use of external oxidants forms the chief highlight of the work. The protocol is scalable and mechanistic studies indicate that the reaction proceeds through an ionic‐Arbuzov like pathway from phosphoranyl radicals. [ABSTRACT FROM AUTHOR]

Rh(I)‐catalyzed decarboxylative arylation of alkynyl cyclic carbonates using commercially available and low‐toxic aryl boronic acids has been disclosed. Depending on the nature of the cyclic carbonates, the methodology provides a straightforward platform to access either substituted 2,3‐allenols or 1,3‐butadiene derivatives. Internal alkynyl cyclic carbonates undergo monoarylation to conveniently afford 2,3‐allenols with high syn‐selectivity for the aryl and hydroxy groups. Whereas, terminal alkynyl carbonates led to the formation of diarylated 1,3‐butadiene derivatives having cis‐configuration for the two aryl groups via allenyl rhodium(I)alkoxide intermediate. The compatibility of various functional groups allowed to develop a library of diversely functionalized scaffolds with excellent regioselectivity in good yields. Late‐stage transformation of a series of natural products highlights the wide applicability of the arylation process. Additionally, scale‐up experiments and downstream transformations of α‐allenol derivatives into other valuable heterocycles illustrate the efficacy of the protocol. [ABSTRACT FROM AUTHOR]

Over the past decade, α‐imino carbenoids generated via transition metal (such as rhodium, nickel, copper, palladium, silver) catalyzed denitrogenative ring‐opening of N‐sulfonyl‐1,2,3‐triazoles have found an extensive account of applications in synthetic organic chemistry. Particularly, they have been widely utilized as a donor/acceptor carbene complex in a range of transformations leading to diverse nitrogen containing compounds and heterocycles. Along the same direction, 3‐diazoindolin‐2‐imines were successfully applied as an alternative source of α‐imino carbenoid precursors for the development of a number of methodologies to access diverse indole derivatives. This review summarizes the insertion reactions of α‐imino metal carbenes derived from N‐sulfonyl‐1,2,3‐triazoles and 3‐diazoindolin‐2‐imines. [ABSTRACT FROM AUTHOR]

Tendons are relatively hypovascular but become hypervascular during both injury and degeneration. This is due to the angiogenic response, or the formation of new blood vessels, to tissue injury. The objective of this study was to evaluate the effect of vascular modulation in the rat Achilles tendons during healing. Fischer rats received a bilateral Achilles incisional injury followed by local injections of vascular endothelial growth factor (VEGF), anti‐VEGF antibody (B20.4‐1‐1), or saline either early or late during the healing process. Vascular modulation and healing were evaluated using multiple in vivo ultrasound imaging modalities, in vivo functional assessment, and ex vivo measures of tendon compositional and mechanical properties. The late delivery of anti‐VEGF antibody, B20, caused a temporary reduction in healing capacity during a time point where vascularity was also decreased, and then an improvement during a later time point where vascularity was increased relative to control. However, VEGF delivery had a minimal impact on healing and vascular changes in both early and late delivery times. This study was the first to evaluate vascular changes using both in vivo imaging methods and ex vivo histological methods, as well as functional and mechanical outcomes associated with these vascular changes. Clinical significance: this study demonstrates that the alteration of vascular response through the delivery of angiogenic growth factors has the ability to alter tendon healing properties. [ABSTRACT FROM AUTHOR]

ERA5 reanalysis data shows significant correlation between Siberian snow depth in March and following Indian summer monsoon rainfall (ISMR). Whilst the Siberian snow depth is negatively correlated with seasonal monsoon rainfall over most of India, it is positively correlated with the monsoon rain over north‐east Indian regions. This relationship has significantly strengthened during the past 2 decades. We show that the strengthening relationship is more likely related to recent atmospheric circulation changes owing to persistent global warming, particularly the changes in the atmospheric circulation over the North Atlantic. There are indications that during 1999–2018, the extratropical climatic variability (e.g., Arctic Oscillation [AO] and North Atlantic Oscillation [NAO]) significantly influenced Siberian snow in the month of March. In contrast, during the period 1979–1998, the influence of NAO and AO on Siberian snow was negligible. Analysis indicates that Siberian High, a dominant atmospheric circulation system that exerts strong influence on Eurasian weather and climate, has also significantly weakened during the past 2 decades. We hypothesize that the March Siberian snow influences the ISMR through a delayed hydrological response, in which the increased (reduced) accumulated snow during springtime provides wetter (drier) soil during the following summer. This leads to the alternation of the meridional tropospheric temperature gradient. The heavy (less) spring snowfall in north (south) Siberia led to changes in summertime meridional tropospheric temperature gradient, which resulted in the weakening of subtropical westerly jet and Tibetan anticyclone. The reduced intensity of tropical easterly jet connected to Tibetan anticyclone resulted in the weakening of summer monsoon Hadley cell, leading to subsequent suppression of rainfall. This association between Siberian snow and ISMR provides seasonal prediction potential. Key Points: In the backdrop of global warming, relationship between Siberian snow and Indian summer monsoon rainfall (ISMR) has strengthened during past 2 decadesThe association between the Siberian snow and the atmospheric circulation, particularly North Atlantic Oscillation has become more pronounced in recent decadesSiberian snow influences the ISMR via delayed hydrological response [ABSTRACT FROM AUTHOR]

Oropharyngeal leak pressure (OLP) is considered a measure of successful placement, adequate performance and is a useful comparator between supraglottic airway devices (SADs). OLP measurement is based on the premise that the SAD is sited properly in the hypopharynx after blind placements, but the evidence suggests otherwise. Several limitations and controversies surround OLP. This editorial addresses the uses and pitfalls of OLP, the rationale for and methods of ascertaining OLP, the pros and cons of OLP measurement and newer modalities to improve its accuracy. [ABSTRACT FROM AUTHOR]

An efficient Cp*CoIII‐catalyzed C8‐dienylation of quinoline‐N‐oxides was achieved by employing allenes bearing leaving groups at the α‐position as the dienylating agents. The reaction proceeds by CoIII‐catalyzed C−H activation of quinoline‐N‐oxides and regioselective migratory insertion of the allene followed by a β‐oxy elimination, leading to overall dienylation. Site‐selective C−H activation was achieved with excellent selectivity under mild reaction conditions, and 30 mol % of a NaF additive was found to be crucial for the efficient dienylation. The methodology features high stereoselectivity, mild reaction conditions, and good functional‐group tolerance. C8‐alkenylation of quinoline‐N‐oxides was achieved in the case of allenes devoid of leaving groups as coupling partners. Furthermore, gram‐scale preparation and preliminary mechanistic experiments were carried out to gain insights into the reaction mechanism. [ABSTRACT FROM AUTHOR]

An efficient strategy for the synthesis of structurally diverse homotryptamines and allyl amines via a Rh(II)‐catalyzed tandem reaction of 1,2,3‐triazolyl esters with either indoles or 1,3,5‐trimethoxybenzene has been developed. The reaction proceeds via Rh(II)‐catalyzed intramolecular rearrangement of triazoles into 1‐azadienes followed by regioselective nucleophilic addition. The efficiency of the current protocol was illustrated by broad substrate scope, gram scale synthesis and further functionalization of homotryptamines into other biologically relevant heterocycles. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate technical and patient-related factors that can affect the reliability of acoustic radiation force impulse shear wave elastography (ARFI-SWE) in morbidly obese patients.Methods: A prospective single-center study was performed on 41 patients (32 females, 78%) presenting for preoperative evaluation for bariatric surgery. ARFI-SWE was performed using a 6 to 1.5 MHz curved (6C1) transducer. Hepatic steatosis was mild, moderate, severe, and absent in 24.4%, 12.2%, 43.9%, and 19.5% of patients, respectively. Interquartile range/median (IQR/M) ranged from 0.05 to 2.07 (0.78 ± 0.56 m/s). Twenty patients (48.7%) had reliable measurements (IQR/M < 0.3). Shear wave velocity (SWV) values were >1.34 m/s (clinically significant fibrosis) in 25 of 41 patients (61%) and >2.2 m/s (advanced fibrosis) in 19 patients (46%).Results: Median SWV was correlated with body mass index (BMI; correlation coefficient [CC] = .37; 95% CI, 0.07-0.61; P-value = .03) and skin-to-liver capsule distance (SLD) (CC = .38; 95% CI, 0.09-0.62; P-value = .01). IQR/M was higher in patients with BMI > 40 (0.24 ± 0.11 vs 0.39 ± 0.25, P-value = .031) and SLD > 3 cm (0.46 ± 0.27 vs 0.23 ± 0.08, P-value = .001), and there was higher number of unreliable examinations among patient with SLD > 3 cm (16/23 vs 5/18, P-value = .01).Conclusion: ARFI-SWE is technically more challenging among patients with higher BMI and SLD, resulting in a higher number of unreliable studies, which highlights the need for further advancement of ARFI technology. [ABSTRACT FROM AUTHOR]

Herein, we demonstrate a [RhCp*Cl2]2 catalyzed synthesis of isoindolo[2,1‐b]isoquinolin‐5(7H)‐one derivatives from N‐(pivaloyloxy)benzamides and p‐quinone methides under redox neutral conditions. p‐Quinone methide derivatives were engaged for the first time as precursors in C–H activation reactions and the cascade sequence consists of Rh(III)‐catalyzed C–H activation, alkyne insertion followed by an intramolecular 1,6‐conjugate addition. This novel tandem reaction strategy offers a rapid and straightforward access to complex fused isoquinolinone derivatives in an efficient manner. [ABSTRACT FROM AUTHOR]

An effective and pragmatic strategy for the synthesis of structurally diverse indolo[2,3‐c]isoquinolin‐5‐ones has been developed via a Rh(III)‐catalyzed C−H activation and [4+2] annulation reaction of N‐methoxybenzamides and 3‐diazoindolin‐2‐imines. The reaction involves the efficient formation of two new (one C−C and one C−N) bonds under operationally simple conditions and has the benefits of a broad substrate scope. [ABSTRACT FROM AUTHOR]

Herein, we report an efficient synthesis of azaspiro[4,5]‐decanes and azaspiro[4,5]‐trienones by the radical cascade spirocyclization of N‐benzylacrylamides or N‐arylpropiolamides respectively. These reactions proceed under metal free conditions and involve in situ generation of aryl sulfonyl radicals from DABSO and aryl diazonium salts. Furthermore, a catalyst free visible light mediated protocol was developed for the sulfonylative spirocyclization of N‐aryl alkynamides using diaryliodonium salts. The utility of these protocols were justified by the excellent compatability of a wide range of functional groups, good yields and scalablity under mild conditions at room temperature. [ABSTRACT FROM AUTHOR]

A mild and facile method to access sulfenylated dihydrochromenones via a visible light mediated thiol‐yne/conjugate addition cascade of alkyne‐tethered cyclohexadienones, using cheap and readily available organic photoredox catalyst (Eosin Y) is demonstrated. The utility and sustainability of the protocol were further justified by the high yields, excellent diastereoselectivities, broad substrate scope, gram scale synthesis, green chemistry metrics (atom economy and efficiency) and further synthetic transformations of the products. [ABSTRACT FROM AUTHOR]

A convergent strategy for the synthesis of biologically relevant C4‐substituted indole scaffolds was demonstrated using Pd(II)‐catalyzed remote C−H functionalization of indoles and azaindoles. The reaction displays high regioselectivity for the C4‐position of indole‐3‐carbaldehydes using glycine as an inexpensive transient directing group. Notable features of this transformation include the selective formation of six‐membered palladacyle and excellent functional group tolerance. [ABSTRACT FROM AUTHOR]

Objectives: Vascular resistance is known to be one of the determinants of pulsatile flow. This study aimed to investigate whether quantitative 2‐dimensional Doppler ultrasound can capture and evaluate the pulsatility within the placental bed vasculature. Methods: The placental bed vasculature was imaged by directional power Doppler ultrasound. Ten‐second cine clips were recorded by using standardized machine settings. A region of interest with a prominent Doppler signal in the uteroplacental interface was analyzed for the percentage of vascularity to generate a time‐vascularity waveform. A vascular pulsatility index representing variation over the cardiac cycle was calculated by the ratio of the systolic‐diastolic difference in vascularity to the mean vascularity. The acquisitions were repeated with 6 different pulse repetition frequencies (PRFs) and 3 wall motion filter (WMF) settings to evaluate their impact on the Doppler measurements. Results: Ten sets of cine clips were analyzed for this study. The pulsatile nature of the vascularity was readily apparent in each cine clip. The measured time‐vascularity waveforms showed uniform cyclic variation in vascularity over the cardiac cycle, with systolic vascularity significantly higher than diastolic vascularity at each combination of PRF and WMF (P < .05). A gradual increase in the vascular pulsatility index was observed with an increasing PRF or WMF. Normalization of systolic‐to‐diastolic measurement provided a stable vascular assessment across the range of PRFs. Conclusions: Doppler cine clips provide a dynamic representation of the placental bed vasculature and a novel analytic approach to quantitatively evaluating the pulsatility of this critical vascular network. Further work is warranted to explore the reproducibility and clinical potential of this approach. [ABSTRACT FROM AUTHOR]

Abstract: A highly regio‐ and stereoselective PdII‐catalyzed cascade synthesis of biologically relevant chromane derivatives from easily available enynes was developed under operationally simple conditions. The cascade reaction consists of nucleopalladation of alkynes, insertion of the alkene and protonation. When CuCl2 was employed as nucleophile, a cis‐chloropalladation initiates the cascade. Whereas in the case of AcOH, a trans‐acetoxypalladation takes place. [ABSTRACT FROM AUTHOR]

Present study was carried out to investigate the effect of long-term mobile phone radiation exposure in different operative modes (Dialing, Receiving, and Stand-by) on immature male mice. Three-week old male mice were exposed to mobile phone (1800 MHz) radiation for 3 hr/day for 120 days in different operative modes. To check the changes/alteration in testicular histo architecture and serum testosterone level, HE staining and ELISA was performed respectively. Further, we have checked the redox status (ROS, NO, MDA level, and antioxidant enzymes: SOD, CAT, and GPx) by biochemical estimation, alteration in the expression of pro-apoptotic proteins (p53 and Bax), active executioner caspase-3, full length/uncleaved PARP-1 (DNA repair enzyme), anti-apoptotic proteins (Bcl-2 and Bcl-xL) in testes by immunofluorescence and cytosolic cytochrome-c by Western blot. Decreased seminiferous tubule diameter, sperm count, and viability along with increased germ cells apoptosis and decreased serum testosterone level, was observed in the testes of all the mobile phone exposed mice compared with control. We also observed that, mobile phone radiation exposure in all the three different operative modes alters the testicular redox status via increasing ROS, NO, and MDA level, and decreasing antioxidant enzymes levels leading to enhanced apoptosis of testicular cells by increasing the expression of pro-apoptotic and apoptotic proteins along with decreasing the expression of anti-apoptotic protein. On the basis of results, it is conclude that long-term mobile phone radiation exposure induced oxidative stress leads to apoptosis of testicular cells and thus impairs testicular function. [ABSTRACT FROM AUTHOR]

Abstract: An efficient and convenient cobalt(III)‐catalyzed highly diastereoselective strategy was demonstrated for the synthesis of epoxybenzophenanthridinone derivatives. The sp2 C−H activation of N‐methoxybenzamides and their annulation reaction with 7‐oxa/aza benzonorbornadienes proceeds under mild conditions and exhibits excellent functional group tolerance. In addition, the products were transformed to biologically relevant phenanthridinones by an acid‐catalyzed ring opening/aromatization sequence. [ABSTRACT FROM AUTHOR]

Abstract: Bar‐built estuaries are unique ecosystems characterized by the presence of a sandbar barrier, which separates the estuary from the ocean for extended periods and can naturally reopen to the ocean with heavy rainfall and freshwater inflows. The physical effects associated with the transition from closed to open state, specifically water mixing and sediment resuspension, often indirectly worsen water quality conditions and are suspected to drive near‐annual fish kills at the Pescadero estuary in northern California. The effects of sediment acid‐volatile sulfide (AVS) oxidation, specifically oxygen depletion, acidification, and metal release, are believed to aggravate water conditions for fish but remain poorly understood. We performed slurry incubations containing sediment from 4 sites in the Pescadero estuary, representing a gradient from the Pacific Ocean to freshwater tributaries. We measured near‐maximum rates of aqueous hydrogen sulfide oxidation, sediment AVS oxidation, sulfate production, and acidification, as well as near‐maximum release rates of iron (Fe), manganese (Mn), and zinc (Zn) to the water column. We estimated AVS oxidation rates of 8 to 21 mmol S kg−1  d−1, which were 3 orders of magnitude higher than aqueous hydrogen sulfide oxidation rates, 6 to 26 μmol S kg−1  d−1. We suggest that aqueous hydrogen sulfide cannot be responsible for the observed kills because of low concentrations and minimal oxidative effects on pH and metal concentrations. However, the oxidative effects of AVS are potentially severe, decreasing pH to strongly acidic levels and releasing aqueous Fe, Mn, and Zn concentrations up to 11.2 mM, 0.46 mM, and 88 μM, respectively, indicating a potential role in worsening water conditions for fish in the Pescadero estuary. Environ Toxicol Chem 2018;37:993–1006. © 2017 SETAC [ABSTRACT FROM AUTHOR]

Abstract: A convenient and simple, RhII‐catalyzed denitrogenative method for the synthesis of biologically interesting 2‐amino‐benzoxazinones and 5‐amino‐oxadiazoles from readily available isatoic anhydrides and oxadiazolones has been developed. These reactions proceed via an O−H insertion onto α‐imino RhII–carbenoid species followed by a rearrangement. The scope of the reaction can also be extended to benzoxazinones to access amino‐substituted benzoxazines. [ABSTRACT FROM AUTHOR]

Abstract: Cobalt‐catalyzed sp2 C−H bond functionalization of diarylphosphinamides with heterobicyclic alkenes was demonstrated at room temperature employing commercially available cobalt(II)‐salts. The effectiveness of this strategy was illustrated with the reaction of various 8‐aminoquinoline derived phosphinic amides and 7‐oxa/azabenzonorbornadienes. The reaction conditions exhibited excellent functional group tolerance and high diastereoselectivities. Furthermore, extension of this approach to the preparation of polyaryl cyclic phosphinamides was achieved through the dehydrative ring opening/aromatization sequence. [ABSTRACT FROM AUTHOR]

Herein, we report a copper-catalyzed novel, highly efficient, and modular cascade annulation reaction for the synthesis of quinoline derivatives starting from easily available alkynes, isothiocyanates, and diaryliodonium salts. The reaction displayed excellent regioselectivities, when unsymmetrical alkynes were employed as partners, giving access to diversely functionalized quinolines in good to excellent yields for a wide range of functional groups. [ABSTRACT FROM AUTHOR]

A cascade reaction, consisting of a palladium-catalyzed regioselective aerobic oxidative carbocyclization-borylation of bisallenes and a final aldehyde trapping, afforded triene alcohols with high diastereoselectivity. The cascade reaction occurs under mild reaction conditions and proceeds via an allylboron intermediate that is trapped by the aldehyde in a stereoselective manner. [ABSTRACT FROM AUTHOR]

Purpose: The objectives of our study were to assess the accuracy of hepatorenal index (HRI) in detection and grading of hepatic steatosis and to evaluate various factors that can affect the HRI measurement.Methods: Forty-five patients, who had undergone an abdominal sonographic examination within 30 days of liver biopsy, were enrolled. The HRI was calculated as the ratio of the mean brightness levels of the liver and renal parenchymas. The effect of the measurement technique on the HRI was evaluated by using various sizes, depths, and locations of the regions of interest (ROIs) in the liver. The measurements were obtained by two observers. The HRI was compared with the subjective grading of steatosis.Results: The optimal HRI cutoff to detect steatosis was 2.01, yielding a sensitivity of 62.5% and specificity of 95.2%. Subjective grading had a sensitivity of 87.5% and specificity of 62.5%. HRIs of the hepatic steatosis group were statistically different from the no-steatosis group (p < 0.05). However, there was no statistically significant difference between mild steatosis and no-steatosis groups (p value = 0.72). There was a strong correlation between different HRIs based on variable placements of ROIs, except when the ROIs were positioned randomly. Interclass correlation coefficient for measurements performed by two observers was 0.74 (confidence interval: 0.58-0.86).Conclusions: The HRI is an effective tool for detecting hepatic steatosis. It provides similar accuracy for different methods of ROI placement (except for random placement) and has good interobserver agreement. It, however, is unable to effectively differentiate between absent and mild steatosis. © 2016 Wiley Periodicals, Inc. J Clin Ultrasound 44:580-586, 2016. [ABSTRACT FROM AUTHOR]

The reactivity of allenes in transition-metal-catalyzed C−H activation chemistry is governed by the formation of either alkenyl-metal (M-alkenyl) or metal-π-allyl intermediates. Although either protonation or a β-hydride elimination is feasible with a M-alkenyl intermediate, cyclization has remained unexplored to date. Furthermore, due to the increased steric hindrance, the regioselectivity for the intramolecular cyclization of the metal-π-allyl intermediate was hampered towards the more substituted side. To address these issues, a unified approach to synthesize a diverse array of biologically and pharmaceutically relevant heterocyclic moieties by cobalt-catalyzed directed C−H functionalization was envisioned. Upon successful implementation, the present strategy led to the regioselective formation of dihydroisoquinolin-1(2 H)-ones, isoquinolin-1(2 H)-ones, dihydropyridones, and pyridones. [ABSTRACT FROM AUTHOR]

Purpose: Measurement of the arrival times of thermoacoustic waves induced by pulsed proton dose depositions (protoacoustics) may provide a proton range verification method. The goal of this study is to characterize the required dose and protoacoustic proton range (distance) verification accuracy in a homogeneous water medium at a hospital-based clinical cyclotron. Methods: Gaussian-like proton pulses with 17 µs widths and instantaneous currents of 480 nA (5.6×107 protons/pulse, 3.4 cGy/pulse at the Bragg peak) were generated by modulating the cyclotron proton source with a function generator. After energy degradation, the 190 MeV proton pulses irradiated a water phantom, and the generated protoacoustic emissions were measured by a hydrophone. The detector position and proton pulse characteristics were varied. The experimental results were compared to simulations. Different arrival time metrics derived from acoustic waveforms were compared, and the accuracy of protoacoustic time-of-flight distance calculations was assessed. Results: A 27 mPa noise level was observed in the treatment room during irradiation. At 5 cm from the proton beam, an average maximum pressure of 5.2 mPa/1×107 protons (6.1 mGy at the Bragg peak) was measured after irradiation with a proton pulse with 10%-90% rise time of 11 µs. Simulation and experiment arrival times agreed well, and the observed 2.4 µs delay between simulation and experiment is attributed to the difference between the hydrophone's acoustic and geometric centers. Based on protoacoustic arrival times, the beam axis position was measured to within (x,y) = (-2.0, 0.5)±1 mm. After deconvolution of the exciting proton pulse, the protoacoustic compression peak provided the most consistent measure of the distance to the Bragg peak, with an error distribution with mean = -4.5 mm and standard deviation = 2.0 mm. Conclusions: Based on water tank measurements at a clinical hospital-based cyclotron, protoacoustics is a potential method for measuring the beam's position (x and y within 2.0 mm) and Bragg peak range (2.0 mm standard deviation), although range verification will require simulation or experimental calibration to remove systematic error. Based on extrapolation, a protoacoustic arrival time reproducibility of 1.5 µs (2.2 mm) is achievable with 2 Gy of total deposited dose. Of the compared methods, deconvolution of the excitation proton pulse is the best technique for extracting protoacoustic arrival times, particularly if there is variation in the proton pulse shape. [ABSTRACT FROM AUTHOR]

Purpose: To measure the acoustic signal generated by a pulsed proton spill from a hospital-based clinical cyclotron. Methods: An electronic function generator modulated the IBA C230 isochronous cyclotron to create a pulsed proton beam. The acoustic emissions generated by the proton beam were measured in water using a hydrophone. The acoustic measurements were repeated with increasing proton current and increasing distance between detector and beam. Results: The cyclotron generated proton spills with rise times of 18 μs and a maximum measured instantaneous proton current of 790 nA. Acoustic emissions generated by the proton energy deposition were measured to be on the order of mPa. The origin of the acoustic wave was identified as the proton beam based on the correlation between acoustic emission arrival time and distance between the hydrophone and proton beam. The acoustic frequency spectrum peaked at 10 kHz, and the acoustic pressure amplitude increased monotonically with increasing proton current. Conclusions: The authors report the first observation of acoustic emissions generated by a proton beam from a hospital-based clinical cyclotron. When modulated by an electronic function generator, the cyclotron is capable of creating proton spills with fast rise times (18 µs) and high instantaneous currents (790 nA). Measurements of the proton-generated acoustic emissions in a clinical setting may provide a method for in vivo proton range verification and patient monitoring. [ABSTRACT FROM AUTHOR]

Background Although paediatric growth charts are recommended for weight assessment prior to age 20, many teenagers transition earlier to adult care where absolute body mass index ( BMI) is used. This study examines concordance of weight classification in older teenagers using paediatric percentiles and adult thresholds. Methods BMI from 23 640 US teens ages 18-19 years were classified using paediatric BMI percentile criteria for underweight (< 5th), normal (5th to < 85th), overweight (85th to < 95th), obesity (≥ 95th) and severe obesity (≥ 120% × 95th percentile) and adult BMI (kg m−2) criteria for underweight (< 18.5), normal (18.5-24.9), overweight (25-29.9) and obesity: class I (30-34.9), class II (35-39.9) and class III (≥ 40). Concordance was examined using the kappa (κ) statistic. Blood pressure ( BP) from the same visit was classified hypertensive for BP ≥ 140/90. Results The majority of visits (72.8%) occurred in adult primary care. Using paediatric/adult criteria, 3.4%/5.2% were underweight, 66.6%/58.8% normal weight, 15.7%/21.7% overweight, 14.3%/14.3% obese and 4.9%/6.0% severely/class II-III obese, respectively. Paediatric and adult classification for underweight, normal, overweight and obesity were concordant for 90.3% (weighted κ 0.87 [95% confidence interval, 0.87-0.88]). For severe obesity, BMI ≥ 120% × 95th percentile showed high agreement with BMI ≥ 35 kg m−2 (κ 0.89 [0.88-0.91]). Normal-weight males and moderately obese females by paediatric BMI percentile criteria who were discordantly classified into higher adult weight strata had a greater proportion with hypertensive BP compared with concordantly classified counterparts. Conclusions Strong agreement exists between US paediatric BMI percentile and adult BMI classification for older teenagers. Adult BMI classification may optimize BMI tracking and risk stratification during transition from paediatric to adult care. [ABSTRACT FROM AUTHOR]

A highly efficient oxidative carbocyclization-carbonylation reaction cascade of allenynes and enallenes has been developed using a PdII salt in low catalytic amounts under ambient temperature and pressure (1 atm of carbon monoxide). The use of DMSO as an additive was found to be important for an efficient reaction. A wide range of alcohols as trapping reagents were used to give the corresponding esters in good yields. [ABSTRACT FROM AUTHOR]

What is already known about this subject The prevalence of obesity in the United States has increased dramatically over the past three decades., There is a growing spectrum of severe obesity among children and adolescents., Obesity trends and race/ethnic differences may be evident at a young age., What this study adds Among children aged 3-5 years, the prevalence of obesity and severe obesity was higher in boys than in girls, and highest among children of Hispanic ethnicity., Within this young age group, higher body mass index (BMI) was associated with greater height percentile., Among obese children aged 5 years, provider recognition of obesity or elevated BMI was high, approaching 80% of children., Background Early childhood adiposity may have significant later health effects. This study examines the prevalence and recognition of obesity and severe obesity among preschool-aged children. Methods The electronic medical record was used to examine body mass index ( BMI), height, sex and race/ethnicity in 42 559 children aged 3-5 years between 2007 and 2010. Normal or underweight ( BMI < 85th percentile); overweight ( BMI 85th-94th percentile); obesity ( BMI ≥ 95th percentile); and severe obesity ( BMI ≥ 1.2 × 95th percentile) were classified using the 2000 Centers for Disease Control and Prevention growth charts. Provider recognition of elevated BMI was examined for obese children aged 5 years. Results Among 42 559 children, 12.4% of boys and 10.0% of girls had BMI ≥ 95th percentile. The prevalence was highest among Hispanics (18.2% boys, 15.2% girls), followed by blacks (12.4% boys, 12.7% girls). A positive trend existed between increasing BMI category and median height percentile, with obesity rates highest in the highest height quintile. The prevalence of severe obesity was 1.6% overall and somewhat higher for boys compared with girls (1.9 vs. 1.4%, P < 0.01). By race/ethnicity, the highest prevalence of severe obesity was seen in Hispanic boys (3.3%). Among those aged 5 years, 77.9% of obese children had provider diagnosis of obesity or elevated BMI, increasing to 89.0% for the subset with severe obesity. Conclusions Obesity and severe obesity are evident as early as age 3-5 years, with race/ethnic trends similar to older children. This study underscores the need for continued recognition and contextualization of early childhood obesity in order to develop effective strategies for early weight management. [ABSTRACT FROM AUTHOR]

Fault diagnosis includes the main task of classification. Bayesian networks (BNs) present several advantages in the classification task, and previous works have suggested their use as classifiers. Because a classifier is often only one part of a larger decision process, this article proposes, for industrial process diagnosis, the use of a Bayesian method called dynamic Markov blanket classifier that has as its main goal the induction of accurate Bayesian classifiers having dependable probability estimates and revealing actual relationships among the most relevant variables. In addition, a new method, named variable ordering multiple offspring sampling capable of inducing a BN to be used as a classifier, is presented. The performance of these methods is assessed on the data of a benchmark problem known as the Tennessee Eastman process. The obtained results are compared with naive Bayes and tree augmented network classifiers, and confirm that both proposed algorithms can provide good classification accuracies as well as knowledge about relevant variables. [ABSTRACT FROM AUTHOR]

ABSTRACT Injectable hydrogels have attracted a great deal of attention as cell carriers and bioactive agents in regenerative medicine due to their ability to fill complex three-dimensional (3D) tissue gaps and relative ease of in vivo administration. Polysaccharide-based hydrogels can provide microenvironments that favor tissue regeneration and biocompatibility due to their chemical similarities with native extracellular matrix components. This manuscript reports the in vitro application of an injectable chitosan-based polysaccharide hydrogel for cell and protein delivery. Crosslinked hydrogels were produced by the reaction between the amino functionality of chitosan and the aldehyde of dextran aldehyde resulting in an imine bond (Schiff's base) formation in aqueous solutions. This approach eliminated the use of additional crosslinking agents which may pose undesired side effects regarding cytotoxicity and biocompatibility. Additionally, we demonstrate versatility of the gel in terms of its fabrication, and ability to alter mechanical properties by changing the crosslinking extent due to aldehyde content. Bovine serum albumin (BSA), used as a model protein, followed a steady release pattern from the gel. BSA release was dependent on the extent of hydrogel crosslinking. Increase in crosslinking extent resulted in improved mechanical properties and sustained release of BSA. Human fetal osteoblasts encapsulated into the hydrogel showed at least 70% viability and continued to proliferate under in vitro culture. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 39934. [ABSTRACT FROM AUTHOR]

Purpose: To use feed-forward active contours (snakes) to track and measure brachial artery vasomotion on ultrasound images recorded in both transverse and longitudinal views; and to compare the algorithmˈs performance in each view. Methods: Longitudinal and transverse view ultrasound image sequences of 45 brachial arteries were segmented by feed-forward active contour (FFAC). The segmented regions were used to measure vasomotion artery diameter, cross-sectional area, and distention both as peak-to-peak diameter and as area. ECG waveforms were also simultaneously extracted frame-by-frame by thresholding a running finite-difference image between consecutive images. The arterial and ECG waveforms were compared as they traced each phase of the cardiac cycle. Results: FFAC successfully segmented arteries in longitudinal and transverse views in all 45 cases. The automated analysis took significantly less time than manual tracing, but produced superior, well-behaved arterial waveforms. Automated arterial measurements also had lower interobserver variability as measured by correlation, difference in mean values, and coefficient of variation. Although FFAC successfully segmented both the longitudinal and transverse images, transverse measurements were less variable. The cross-sectional area computed from the longitudinal images was 27% lower than the area measured from transverse images, possibly due to the compression of the artery along the image depth by transducer pressure. Conclusions: FFAC is a robust and sensitive vasomotion segmentation algorithm in both transverse and longitudinal views. Transverse imaging may offer advantages over longitudinal imaging: transverse measurements are more consistent, possibly because the method is less sensitive to variations in transducer pressure during imaging. [ABSTRACT FROM AUTHOR]