Encouraging the resumption of economic activity after COVID-19: Evidence from a large scale-field experiment in China.

As the COVID-19 pandemic comes to an end, governments find themselves facing a new challenge: motivating citizens to resume economic activity. What is an effective way to do so? We investigate this question using a field experiment in the city of Zhengzhou, China, immediately following the end of the city's COVID-19 lockdown. We assessed the effect of a descriptive norms intervention providing information about the proportion of participants' neighbors who have resumed economic activity. We find that informing individuals about their neighbors' plans to visit restaurants increases the fraction of participants visiting restaurants by 12 percentage points (37%), among those participants who underestimated the proportion of neighbors who resumed economic activity. Those who overestimated did not respond by reducing restaurant attendance (the intervention yielded no "boomerang" effect); thus, our descriptive norms intervention yielded a net positive effect. We explore the moderating role of risk preferences and the effect of the intervention on subjects' perceived risk of going to restaurants, as well as the contrast with an intervention for parks, which were already perceived as safe. All of these analyses suggest our intervention worked by reducing the perceived risk of going to restaurants.

Topologically Protected Photovoltaics in Bi Nanoribbons.

Photovoltaic efficiency in solar cells is hindered by many unwanted effects. Radiative channels (emission of photons) sometimes mediated by nonradiative ones (emission of phonons) are principally responsible for the decrease in exciton population before charge separation can take place. One such mechanism is electron-hole recombination at surfaces or defects where the in-gap edge states serve as the nonradiative channels. In topological insulators (TIs), which are rarely explored from an optoelectronics standpoint, we show that their characteristic surface states constitute a nonradiative decay channel that can be exploited to generate a protected photovoltaic current. Focusing on two-dimensional TIs, and specifically for illustration purposes on a Bi(111) monolayer, we obtain the transition rates from the bulk excitons to the edge states. By breaking the appropriate symmetries of the system, one can induce an edge charge accumulation and edge currents under illumination, demonstrating the potential of TI nanoribbons for photovoltaics.

A True Reverse Anomeric Effect Does Exist After All: A Hydrogen Bonding Stereocontrolling Effect in 2-Iminoaldoses.

The reverse anomeric effect is usually associated with the equatorial preference of nitrogen substituents at the anomeric center. Once postulated as another anomeric effect with explanations ranging from electrostatic interactions to delocalization effects, it is now firmly considered to be essentially steric in nature. Through an extensive research on aryl imines from 2-amino-2-deoxyaldoses, spanning nearly two decades, we realized that such substances often show an anomalous anomeric behavior that cannot easily be rationalized on the basis of purely steric grounds. The apparent preference, or stabilization, of the ß-anomer takes place to an extent that not only neutralizes but also overcomes the normal anomeric effect. Calculations indicate that there is no stereoelectronic effect opposing the anomeric effect, resulting from the repulsion between electron lone pairs on the imine nitrogen and the endocyclic oxygen. Such data and compelling structural evidence unravel why the exoanomeric effect is largely inhibited. We are now confident, as witnessed by 2-iminoaldoses, that elimination of the exo-anomeric effect in the α-anomer is due to the formation of an intramolecular hydrogen bond between the anomeric hydroxyl and the iminic nitrogen, thereby accounting for a true electronic effect. In addition, discrete solvation may help justify the observed preference for the ß-anomer.

From Potential Prebiotic Synthons to Useful Chiral Scaffolds: A Synthetic and Structural Reinvestigation of 2-Amino-Aldononitriles.

This paper explores and revisits in detail the formation and characterization of sugar-based aminonitriles, whose ultimate origin can be traced to the interaction of biomolecules with cyanide. Although the synthesis and spectroscopic data of 2-amino-aldononitriles were reported long ago, there are both contradictory and confusing results among the published data. We have now addressed this concern through an exhaustive structural elucidation of acylated 2-amino- and 2-alkyl(aryl)amino-2-deoxyaldonitriles using mass spectrometry and FT-IR, FT-Raman, and NMR spectroscopies. Several structures could be unambiguously determined through single-crystal X-ray diffraction, which allowed us to correct other misassignments. Moreover, this study unveils how steric and electronic effects influence the acylation outcome of the amino, (alkyl, aryl)amino, or acetamido group at C-2. The chirality at the latter, which was assigned tentatively through optical rotation correlation, and hence the preferential threo stereochemistry generated during the cyanohydrin synthesis of 2-amino-2-deoxy aldononitriles have now been established with confidence.

Monitoring Indicators of Universal Access to Accessible and Safe Anesthetic and Surgical Care in a Peruvian Region: An Ambispective Study.

INTRODUCTION: The Lancet Commission on Global Surgery indicators for monitoring anesthetic and surgical care allow the identification of access barriers, evaluate the safety of surgeries, facilitate planning, and assess changes over time. The primary objective was to measure these indicators in all health facilities of a Peruvian region in 2020. METHODS: This was an ambispective observational study to measure the anesthetic and surgical care indicators in Piura, a region in Peru, between January 2020 and June 2021. Public and private health facilities in the Piura region that performed surgical care or had specialists from any surgical specialty participated in the study. Data were collected from all regional health facilities that provided surgical care to estimate the density of surgical workforce. Likewise, the percentage of the population with access to an operating room within 2 h was estimated using georeferenced tools. Finally, a public database was accessed to determine the surgical volume, the percentage of the regional population protected with health insurance. RESULTS: In 2020, 88.4% of the inhabitants of this Peruvian region had access to timely essential surgery. There were 18.4 surgical specialists and 1174 surgeries per 100,000 populations, and 91% of the population had health insurance. In addition, there was a rate of 2.1 working operating rooms per 100,000 inhabitants in 2021. CONCLUSIONS: This Peruvian region presented an increasing trend with respect to the population's access to essential and timely surgical care, and health insurance coverage. However, the workforce distribution was inequitable among the provinces of the region, the surgical volume was reduced, and timely access was hindered because of the SARS-CoV-2 pandemic.

Schiff Bases and Stereocontrolled Formation of Fused 1,3-Oxazolidines from 1-Amino-2-Indanol: A Systematic Study on Structure and Mechanism.

This paper thoroughly explores the formation of Schiff bases derived from salicylaldehydes and a conformationally restricted amino alcohol (1-amino-2-indanol), as well as the generation of 1,3-oxazolidines, a key heterocyclic core present in numerous bioactive compounds. We provide enough evidences, both experimental-including crystallographic analyses and DFT-based calculations on imine/enamine tautomerism in the solid state and solution. In the course of imine formation, a pentacyclic oxazolidine-oxazine structure could be isolated with complete stereocontrol, whose configuration has been determined by merging theory and experiment. Mechanistic studies reveal that, although oxazolidines can be obtained under kinetic conditions, the prevalence of imines obeys to thermodynamic control as they are the most stable structures. The stereochemical outcome of imine cyclization under acylating conditions leads to formation of 2,4-trans-oxazolidines.

Chiral Single-Molecule Potentiometers Based on Stapled ortho- Oligo(phenylene)ethynylenes.

We report on the chemical design of chiral molecular junctions with stress-dependent conductance, whose helicity is maintained during the stretching of a single molecule junction due to the stapling of both ends of the inner helix. In the reported compounds, different conductive pathways are observed, with clearly different conductance values and plateau-length distributions, attributed to different conformations of the helical structures. The large chiro-optical responses and the potential use of these molecules as unimolecular spin filters have been theoretically proved using state-of-the-art Density Functional Theory (DFT) calculations, including a fully ab-initio estimation of the CISS-originating spin polarization which is done, for the first time, for a realistic molecular system.

A synthetically benign one-pot construction of enamino-xanthene dyes.

Polyhydroxylated phenols are components of biomass and precursors of pigments in plants. This paper reports a novel entry to xanthene dyes, involving the reaction of 2,4,6-trihydroxybenzaldehyde with primary aliphatic amines. This catalyst-free synthesis exhibits a high atom economy and can be conducted under eco-friendly conditions and operational simplicity.

Franckeite as an Exfoliable Naturally Occurring Topological Insulator.

Franckeite is a natural superlattice composed of two alternating layers of different composition which has shown potential for optoelectronic applications. In part, the interest in franckeite lies in its layered nature which makes it easy to exfoliate into very thin heterostructures. Not surprisingly, its chemical composition and lattice structure are so complex that franckeite has escaped screening protocols and high-throughput searches of materials with nontrivial topological properties. On the basis of density functional theory calculations, we predict a quantum phase transition originating from stoichiometric changes in one of franckeite composing layers (the quasihexagonal one). While for a large concentration of Sb, franckeite is a sequence of type-II semiconductor heterojunctions, for a large concentration of Sn, these turn into type-III, much alike InAs/GaSb artificial heterojunctions, and franckeite becomes a strong topological insulator. Transmission electron microscopy observations confirm that such a phase transition may actually occur in nature.

Liraglutide hospital discharge trial: A randomized controlled trial comparing the safety and efficacy of liraglutide versus insulin glargine for the management of patients with type 2 diabetes after hospital discharge.

AIM: To compare a glucagon-like peptide-1 receptor agonist with basal insulin at hospital discharge in patients with uncontrolled type 2 diabetes in a randomized clinical trial. METHODS: A total of 273 patients with glycated haemoglobin (HbA1c) 7%-10% (53-86 mol/mol) were randomized to liraglutide (n = 136) or insulin glargine (n = 137) at hospital discharge. The primary endpoint was difference in HbA1c at 12 and 26 weeks. Secondary endpoints included hypoglycaemia, changes in body weight, and achievement of HbA1c <7% (53 mmol/mol) without hypoglycaemia or weight gain. RESULTS: The between-group difference in HbA1c at 12 weeks and 26 weeks was -0.28% (95% CI -0.64, 0.09), and at 26 weeks it was -0.55%, (95% CI -1.01, -0.09) in favour of liraglutide. Liraglutide treatment resulted in a lower frequency of hypoglycaemia <3.9 mmol/L (13% vs 23%; P = 0.04), but there was no difference in the rate of clinically significant hypoglycaemia <3.0 mmol/L. Compared to insulin glargine, liraglutide treatment was associated with greater weight loss at 26 weeks (-4.7 ± 7.7 kg vs -0.6 ± 11.5 kg; P < 0.001), and the proportion of patients with HbA1c <7% (53 mmol/mol) without hypoglycaemia was 48% versus 33% (P = 0.05) at 12 weeks and 45% versus 33% (P = 0.14) at 26 weeks in liraglutide versus insulin glargine. The proportion of patients with HbA1c <7% (53 mmol/mol) without hypoglycaemia and no weight gain was higher with liraglutide at 12 (41% vs 24%, P = 0.005) and 26 weeks (39% vs 22%; P = 0.014). The incidence of gastrointestinal adverse events was higher with liraglutide than with insulin glargine (P < 0.001). CONCLUSION: Compared to insulin glargine, treatment with liraglutide at hospital discharge resulted in better glycaemic control and greater weight loss, but increased gastrointestinal adverse events.

Imine or Enamine? Insights and Predictive Guidelines from the Electronic Effect of Substituents in H-Bonded Salicylimines.

Imine and enamine bonds decorate the skeleton of numerous reagents, catalysts, and organic materials. However, it is difficult to isolate at will a single tautomer, as dynamic equilibria occur easily, even in the solid state, and are sensitive to electronic and steric effect, including π-conjugation and H-bonding. Here, using as model Schiff bases generated from salicylaldehydes and TRIS in a set of linear free energy relationships (LFER), we disclose how the formation of either imines or enamines can be controlled and provide a comprehensive framework that captures the structural underpinning of this prediction. This work highlights the potentiality of tailor-made designs en route to compounds with desirable functionality.

IncobotulinumtoxinA for the treatment of spasticity in children with cerebral palsy - a retrospective case series focusing on dosing and tolerability.

BACKGROUND: IncobotulinumtoxinA (Xeomin®) is a botulinum neurotoxin type A with established efficacy in the treatment of upper-limb spasticity in adults. This retrospective case series in a university hospital setting aimed to elucidate the safety and tolerability of incobotulinumtoxinA for treatment of spasticity in children with cerebral palsy. METHODS: Participants received incobotulinumtoxinA injections up to a maximum total dose of 600 U, 24 U/kg body weight. Medical records were reviewed for key demographic information, incobotulinumtoxinA exposure, and adverse effects (AEs). RESULTS: Sixty-nine children were included (mean age [SD], 8.3 [3.9] years; 44/69 [63.8%] male). One-hundred-and-ninety-one injections were administered, with mean (SD) of 2.8 (1.5) treatment cycles/participant and dosing interval of 6.0 (1.7) months. The number of muscles injected increased from 2.4 (1.2) at cycle 1 to 4.2 (1.9) at cycle 6. The mean (SD) total incobotulinumtoxinA dose increased from 191.7 (126.2) U, (8.5 [5.4] U/kg body weight) at cycle 1 to 368.0 (170.1) U, (9.9 [5.5] U/kg body weight) at cycle 6. Seventy four adverse effects (37.5% of injections) were reported, the most frequent was injection pain (93.2% of AEs). Only three AEs were considered directly treatment-related by injectors: muscle weakness, generalized weakness, and fever. CONCLUSIONS: Our clinical experience indicates that incobotulinumtoxinA is a well-tolerated treatment option for focal spasticity in children with cerebral palsy. TRIAL REGISTRATION: As the study was observational and retrospective, no EudraCT registration number was requested. The internal code assigned to the study in the administrative resolution was: 1143-N-15.

Tautomerism and stereodynamics in Schiff bases from gossypol and hemigossypol with N-aminoheterocycles.

Tautomerism plays a pivotal role in structural stabilization and reactivity. Herein we investigate in detail, aided by DFT simulations, the case of gossypol, a naturally occurring atropisomeric dialdehyde showing promising properties as a male contraceptive and an antineoplasic agent. Its toxicity linked to reactive aldehydo groups can be reduced through amino conjugation. The occurrence of either imino or enamino structures is puzzling indeed and a clear-cut rationale is missing yet. N-enamine-N-enamine structures are prevalent or exclusive tautomers for Schiff bases from gossypol, while their corresponding hydrazones only possess N-imine-N-imine structures both in solution and the solid state. The modification of interactions between the lone pairs on the nitrogen atoms by altering the steric hindrance of the non-iminic nitrogen can favor enamine tautomers. This assumption has now been confirmed and, in the solid state, hydrazones from N-aminopiperidine and their cis-2,6-dimethylderivative present bis-imine and bis-enamine structures, respectively. In solution, these compounds exist in equilibrium between both structures. The tautomerization mechanism, analysis of axial chirality and aromaticity in such H-bonded pseudorings are discussed as well.

Electronic effects in tautomeric equilibria: the case of chiral imines from d-glucamine and 2-hydroxyacetophenones.

A one-pot procedure for preparing a series of chiral imines by direct condensation of d-glucamine with 2-hydroxyacetophenones is described. Under conventional acetylation an unexpected mixture of two different peracetylated molecules is obtained, one with an open enamine structure, and the other incorporating an N-acetyl-1,3-oxazolidine into the acyclic skeleton. Surprisingly, both molecules coexist within the crystal's unit cell, as inferred from single-crystal X-ray analysis of a 5-bromo-substituted aryl derivative. Moreover, the 1,3-oxazolidine ring exists as rotational conformers (E,Z) owing to the restricted rotation around the N-acetyl bond. The equilibrium involving imine and enamine structures has been assessed in detail, providing in addition linear free-energy relationships between the tautomerization constants (KT) and the electronic effect of the substituents.

Strong modulation of optical properties in rippled 2D GaSe via strain engineering.

Few-layer GaSe is one of the latest additions to the family of two-dimensional semiconducting crystals whose properties under strain are still relatively unexplored. Here, we study rippled nanosheets that exhibit a periodic compressive and tensile strain of up to 5%. The strain profile modifies the local optoelectronic properties of the alternating compressive and tensile regions, which translates into a remarkable shift of the optical absorption band-edge of up to 1.2 eV between crests and valleys. Our experimental observations are supported by theoretical results from density functional theory calculations performed for monolayers and multilayers (up to seven layers) under tensile and compressive strain. This large band gap tunability can be explained through a combined analysis of the elastic response of Ga atoms to strain and the symmetry of the wave functions.

Long-term efficacy of photodynamic therapy with methyl aminolevulinate in treating Bowen's disease in clinical practice: A retrospective cohort study (2006-2017).

BACKGROUND: Photodynamic treatment with methyl aminolevulinate (MAL-PDT) is considered an effective and highly recommended treatment for Bowen's disease. However, its long-term efficacy remains to be established, as significant differences have been reported in this respect. OBJECTIVE: The aim of the present study was to describe the results of a retrospective analysis of patients with Bowen's disease treated with MAL-PDT during the period 2006-17 at the Costa del Sol Hospital (Marbella, Spain). MATERIAL AND METHODS: This study is based on a retrospective descriptive analysis of the clinical records of patients treated with MAL-PDT from June 2006 to September 2017. The analysis was based on calculating the mean and standard deviation values for the quantitative variables, and frequency distributions for the qualitative ones. The survival curves were plotted by the Kaplan-Meier method, and the log-rank test was used to assess differences in survival between groups. A cox regression analysis was performed to clarify the significant prognostic factors. RESULTS: A total of 537 tumours with histologically confirmed Bowen's disease were treated with MAL-PDT. Recurrence-free survival at one year was 88%, and at 5 years, 71%. Tumour size >300 mm2 (≥21 mm in diameter P = 0.019), its location in the upper extremities (P = 0.029) and patient's age <70 years (P = 0.028) were all associated with an increased risk of recurrence. LIMITATIONS: Given the retrospective design of our study, the possible existence of information bias cannot be ruled out. CONCLUSIONS: Although it is an appropriate treatment option for patients with Bowen's disease, MAL-PDT presents a risk of recurrence of almost 30% at 5 years. Larger lesions (>300 mm2 ; ≥21 mm in diameter) are more likely to recur than smaller ones. Therefore, appropriate selection is needed of the tumour to be treated, and prolonged follow-up should be provided.

Short implants versus bone grafting and standard-length implants placement: a systematic review.

OBJECTIVES: The aim of this study was to conduct a systematic review to compare the survival rates between short implants (length < 10 mm) versus standard-length implants (≥ 10 mm) inserted in grafted bone. As secondary outcomes, marginal bone loss and survival rates of the implant supported prostheses were also analysed. MATERIALS AND METHODS: Randomised controlled trials (RCT) that compared both techniques were searched on three electronic databases till June 2016, a manual search was performed on the bibliography of the collected articles, and the authors were contacted for additional references. The estimates of the interventions were expressed in relative risk (RR), mean implant survival rates and mean differences in marginal bone. RESULTS: Eight RCTs were included in this study. From a total of 458 short implants, 15 failed (mean survival rates = 96.7%), While from 488 regular implants, 13 failed (mean survival rates = 97.3%). The technique did not significantly affect: the implant failure rate (P > 0.05), with RR of 1.34 (95% CI 0.67-2.87), the mean differences of marginal bone loss (P = 0.18; MD - 0.04 mm [- 0.10; 0.02] 95% CI), at loading or prosthesis failures rates (RR:0.98; 95% CI 0.40-2.41). The mean differences of marginal bone at 1 year follow-up (post loading) presented significant marginal changes in the short implant group (P = 0.002; MD - 0.10 mm [- 0.16; - 0.03] 95% CI) although a significant high heterogeneity was found between groups. CONCLUSIONS: This systematic review suggests no difference between both techniques in the treatment of atrophic arches. However, more long-term RCTs are needed to evaluate the predictability at the long run. CLINICAL RELEVANCE: The use of short implants might be considered an alternative treatment, since it usually requires fewer surgical phases and tends to be a more affordable option.

Exploring the influence of meteorological conditions on the performance of a waste stabilization pond at high altitude with structural equation modeling.

Algal photosynthesis plays a key role in the removal mechanisms of waste stabilization ponds (WSPs), which is indicated in the variations of three parameters, dissolved oxygen, pH, and chlorophyll a. These variations can be considerably affected by extreme climatic conditions at high altitude. To investigate these effects, three sampling campaigns were conducted in a high-altitude WSP in Cuenca (Ecuador). From the collected data, the first application of structure equation modeling (SEM) on a pond system was fitted to analyze the influence of high-altitude characteristics on pond performance, especially on the three indicators. Noticeably, air temperature appeared as the highest influencing factors as low temperature at high altitude can greatly decrease the growth rate of microorganisms. Strong wind and large diurnal variations of temperature, 7-20 °C, enhanced flow efficiency by improving mixing inside the ponds. Intense solar radiation brought both advantages and disadvantages as it boosted oxygen level during the day but promoted algal overgrowth causing oxygen depletion during the night. From these findings, the authors proposed insightful recommendations for future design, monitoring, and operation of high-altitude WSPs. Moreover, we also recommended SEM to pond engineers as an effective tool for better simulation of such complex systems like WSPs.

Can we use baseline characteristics to assess which men with moderately symptomatic benign prostatic hyperplasia at risk of progression will benefit from treatment? A post hoc analysis of data from the 2-year CONDUCT study.

PURPOSE: To investigate (in a post hoc analysis of the 2-year CONDUCT study) the characteristics and clinical outcomes of men with moderately symptomatic benign prostatic hyperplasia (BPH) at risk of progression who benefitted from lifestyle changes alone. METHODS: Patients were given lifestyle advice and randomized to a fixed-dose combination (FDC) of dutasteride and tamsulosin or watchful waiting (WW) and followed for 24 months. Patients in the WW group were escalated to tamsulosin if any follow-up International Prostate Symptom Score (IPSS) was equal or greater than the baseline value. Improvements in symptoms (change in IPSS) and quality of life [measured by BPH Impact Index (BII) and question 8 of the IPSS (IPSS-Q8)] were analysed in the FDC group, men who initiated tamsulosin (WW-TAM) and men who received no medical intervention (WW-no treatment) and the impact of baseline variables on IPSS determined. RESULTS: The adjusted mean decrease in IPSS, BII and IPSS-Q8 at each post-baseline visit over 24 months appeared greater in the FDC (n = 369) and WW-no treatment groups (n = 144) than in the WW-TAM group (n = 229). IPSS improvements appeared similar in the FDC group and WW-no treatment subgroup, except in patients with the greatest degree of bother at baseline (BII 7-13). CONCLUSION: BII at baseline may be a more relevant indicator than symptom severity as to whether a patient with moderate symptoms should receive medical therapy or not.