Unsupervised single-image super-resolution for infant brain MRI.

Acquiring high-resolution (HR) MR images of infant brains is challenging due to lengthy scan times and limited subject compliance. Image super-resolution (SR) techniques can generate HR images from low-resolution (LR) inputs, reducing the need for extended acquisitions. However, most existing SR methods require HR images for training, limiting their practical use in real-world scenarios.

Kinetic Resolution of Racemic Amines via Palladium/Chiral Phosphoric Acid-Catalyzed Intramolecular Allylation: Stereodivergent Access to Chiral 1,3-Disubstituted Isoindolines.

This article presents the kinetic resolution (KR) of racemic amines through stereoselective intramolecular allylation with palladium as a catalyst and chiral phosphoric acid as a cocatalyst. The KR reactions have high selectivity factors, producing chiral 1,3-disubstituted isoindolines (DSIs) and recovering enantioenriched amines. Subsequent palladium-catalyzed allylation of the enantioenriched amines, with an achiral Brønsted acid (BA) cocatalyst, yields -DSIs with favorable stereocontrol.

The Design and Fabrication of Shear-Mode Piezoelectric Accelerometers with High Bandwidth Using High Piezoelectric g-Coefficient NKN-Based Ceramics.

In this work, lead-free (NaKLi)NbO + wt.% ZnO (NKLN, = 0 to 0.3) piezoelectric ceramics with high piezoelectric g-coefficients were prepared by conventional solid-state synthesis method.

SCC-NET: segmentation of clinical cancer image for head and neck squamous cell carcinoma.

Purpose: Squamous cell carcinoma (SCC) accounts for 90% of head and neck cancer. The majority of cases can be diagnosed and even treated with endoscopic examination and surgery. Deep learning models have been adopted for various medical endoscopy exams.

Robust Unsupervised Super-Resolution of Infant MRI via Dual-Modal Deep Image Prior.

Magnetic resonance imaging (MRI) is commonly used for studying infant brain development. However, due to the lengthy image acquisition time and limited subject compliance, high-quality infant MRI can be challenging. Without imposing additional burden on image acquisition, image super-resolution (SR) can be used to enhance image quality post-acquisition.

Machine learning for cryosection pathology predicts the 2021 WHO classification of glioma.

Background: Timely and accurate intraoperative cryosection evaluations remain the gold standard for guiding surgical treatments for gliomas. However, the tissue-freezing process often generates artifacts that make histologic interpretation difficult. In addition, the 2021 WHO Classification of Tumors of the Central Nervous System incorporates molecular profiles in the diagnostic categories, so standard visual evaluation of cryosections alone cannot completely inform diagnoses based on the new classification system.

Synergistic Palladium/Chiral Phosphoric Acid-Catalyzed Kinetic Resolution via Stereoselective Intramolecular Substitution of Unactivated Allylic Alcohols.

This paper reports the kinetic resolution of racemic secondary alcohols (-nucleophiles) via stereoselective intramolecular allylic substitution. The reaction was enabled by synergistic palladium and chiral phosphoric acid catalysis and produced chiral -1,3-disubstituted 1,3-dihydroisobenzofurans with a selective factor of up to 60.9 and a diastereomeric ratio of up to 7.

Insight into Stereocontrol in the Asymmetric Intramolecular Allylation with a -Butylsulfinamide Nucleophile: Application in the Synthesis of Chiral Isoindoline-1-Carboxylic Acid Esters.

The asymmetric induction afforded by a chiral sulfinyl group in a palladium/Brønsted-acid-catalyzed intramolecular allylic amination was investigated. Predictions of the diastereoselectivity for various substrates under assumed total thermodynamic control were obtained from density functional theory (DFT), and the correlation with experimental data demonstrates abrupt changes to kinetic control across the substrate scope. The resulting heterocyclic product was readily converted to valuable isoindoline-1-carboxylic acid esters by a two-step oxidation sequence, providing asymmetric access to a key unnatural α-amino acid scaffold.

A 1.9-V all-organic battery-supercapacitor hybrid device with high rate capability and wide temperature tolerance in a metal-free water-in-saltelectrolyte.

Developing battery-supercapacitor hybrid devices (BSHs) is viewed as an efficient route to shorten the gap between supercapacitors and batteries. In this study, a composite hydrogel consisting of perylene tetracarboxylic diimide (PTCDI) and reduced graphene oxide (rGO) is tested as the anode for BSHs in the electrolyte of ammonium acetate (NHAc) with a record concentration of 32 molality (m). This water-in-salt electrolyte exhibits a wide electrochemical stability window of 2.

Palladium/Brønsted-Acid-Catalyzed Diastereoselective Cyclization with Chiral Sulfinamides as Nucleophiles.

This article reports diastereoselective cyclization with chiral sulfinamides as nucleophiles in two reaction pathways: (1) intramolecular allylic substitution and (2) sequential aerobic oxidation with aza-Michael addition. These reactions were enabled by synergistic palladium and Brønsted acid catalysis and produced chiral isoindolines with good yields of 55-92% and high diastereoselectivities of 10:1 to >20:1 dr.

Recalibration of deep learning models for abnormality detection in smartphone-captured chest radiograph.

Image-based teleconsultation using smartphones has become increasingly popular. In parallel, deep learning algorithms have been developed to detect radiological findings in chest X-rays (CXRs). However, the feasibility of using smartphones to automate this process has yet to be evaluated.

Enantioselective Intramolecular Allylic Substitution via Synergistic Palladium/Chiral Phosphoric Acid Catalysis: Insight into Stereoinduction through Statistical Modeling.

The mode of asymmetric induction in an enantioselective intramolecular allylic substitution reaction catalyzed by a combination of palladium and a chiral phosphoric acid was investigated by a combined experimental and statistical modeling approach. Experiments to probe nonlinear effects, the reactivity of deuterium-labeled substrates, and control experiments revealed that nucleophilic attack to the π-allylpalladium intermediate is the enantio-determining step, in which the chiral phosphate anion is involved in stereoinduction. Using multivariable linear regression analysis, we determined that multiple noncovalent interactions with the chiral environment of the phosphate anion are integral to enantiocontrol in the transition state.

Harnessing Noncovalent Interactions in Dual-Catalytic Enantioselective Heck-Matsuda Arylation.

The use of more than one catalyst in one-pot reaction conditions has become a rapidly evolving protocol in the development of asymmetric catalysis. The lack of molecular insights on the mechanism and enantioselectivity in dual-catalytic reactions motivated the present study focusing on an important catalytic asymmetric Heck-Matsuda cross-coupling. A comprehensive density functional theory (M06 and B3LYP-D3) investigation of the coupling between a spirocyclic cyclopentene and 4-fluorophenyl diazonium species under a dual-catalytic condition involving Pd(dba) (dba = trans, trans-dibenzylideneacetone) and chiral 2,2'-binaphthyl diamine (BINAM)-derived phosphoric acids (BDPA, 2,2'-binaphthyl diamine-derived phosphoric acids) is presented.

Enantiodivergent Steglich rearrangement of -carboxylazlactones catalyzed by a chirality switchable helicene containing a 4-aminopyridine unit.

A pseudo-enantiomeric pair of optically switchable helicenes containing a catalytic 4--methylaminopyridine (MAP) bottom unit and a -symmetric, (10,11)-dimethoxymethyl-dibenzosuberane top template was synthesized. They underwent complementary photoswitching at 290 nm (/', <1/>99) and 340 nm (/', 91/9) and unidirectional thermo-rotation at 130 °C (/', >99/<1). They were utilized to catalyze enantiodivergent Steglich rearrangement of - to -carboxylazlactones, with formation of either enantiomer with up to 91% ee () and 94% ee (), respectively.

Preparation of Furo[3,2-c]coumarins from 3-Cinnamoyl-4-hydroxy-2H-chromen-2-ones and Acyl Chlorides: A Bu3P-Mediated C-Acylation/Cyclization Sequence.

A Bu3P-mediated cyclization reaction of 3-cinnamoyl-4-hydroxy-2H-chromen-2-ones though electrophilic addition of acyl chlorides towards the synthesis of highly functionalized furo[3,2-c]coumarins bearing a phosphorus ylide moiety is described. These unprecedented cyclization reaction proceeds under mild reaction conditions within short reaction times (1 min to 1 h), and can be further applied in the synthesis of alkenyl-substituted furo[3,2-c]coumarins by the treatment with carbonyl electrophiles under basic conditions.

Aspirin and nonsteroidal anti-inflammatory drugs after but not before diagnosis are associated with improved breast cancer survival: a meta-analysis.

Purpose: The association between nonsteroidal anti-inflammatory drugs (NSAIDs) and breast cancer survival is still controversial. The aim of our meta-analysis was to assess the survival benefit of NSAIDs.

Methods: A literature search was conducted in PubMed and EMBASE (to September 2014).

Direct β-acylation of 2-arylidene-1,3-indandiones with acyl chlorides catalyzed by organophosphanes.

We have developed an organophosphane-catalyzed direct β-acylation of a series of conjugated systems bearing ketone, amide and ester functionalities using acyl chlorides as trapping reagents. A wide variety of highly functional ketone derivatives were generated efficiently under very mild conditions with high yields according to our protocol. Our adducts can even be utilized as important building blocks for the synthesis of functional tri/tetracyclic pyridazine derivatives.

Intra- and intermolecular hydrogen bonds enhance the fluoride-responsiveness of functionalized glycolipid-based gelators.

We propose a facile approach toward enhancing the efficiency of fluoride-responsive gels through the positioning of functionalized receptor units, allowing tunable intra- and intermolecular hydrogen bonding, in the gelator molecules. We prepared the new glycolipid-based gelator 2 and its hydroxy and methoxy derivatives 2a and 2b, respectively, to study the effects of three types modes of supramolecular assembly: solely intermolecular hydrogen bonding in 2, solely intramolecular hydrogen bonding in 2b, and both inter- and intramolecular hydrogen bonding in 2a. H NMR spectra confirmed the self-assembly interactions of these glycolipid-based gelators.

Fabrication of high-power piezoelectric transformers using lead-free ceramics for application in electronic ballasts.

CuO is doped into (Na(0.5)K(0.5))NbO(3) (NKN) ceramics to improve the piezoelectric properties and thus obtain a piezoelectric transformer (PT) with high output power.

Effects of improved process for CuO-doped NKN lead-free ceramics on high-power piezoelectric transformers.

In this paper, the effects of the electrical proper- ties of CuO-doped (Na(0.5)K(0.5))NbO(3) (NKN) ceramics prepared separately using the B-site oxide precursor method (BO method) and conventional mixed-oxide method (MO method) on high-power piezoelectric transformers (PTs) were investigated.

Doping effects of CuO additives on the properties of low-temperature-sintered PMnN-PZT-based piezoelectric ceramics and their applications on surface acoustic wave devices.

To develop the anisotropic ceramic substrate with low sintering temperature for surface acoustic wave (SAW) applications, the low cost and feasible material with moderate piezoelectric properties, good dielectric properties, and higher Curie temperature were explored. The piezoelectric ceramics with compositions of Pb[(Mn(1/3)Nb(2/3))(0.06-) (Zr(0.

The improvement of dynamic characteristics of ultrasonic therapeutic transducers using fine-grain PZT-based piezoceramics.

Optimizing the dynamic resonant characteristics of ultrasonic therapeutic transducers depends most importantly on fine-grain piezoceramics with good resonant properties. In this paper, we prepare and compare modified Pb(0.99)Sr(0.