Genome-wide variants and optimal allelic combinations for citric acid in tomato.

Citric acid (CA) plays a crucial role as a fruit flavor enhancer and serves as a mediator in multiple metabolic pathways in tomato fruit development. Understanding factors influencing CA metabolism is essential for enhancing fruit flavor and CA-mediated biological processes. The accumulation of CA, however, is influenced by a complex interplay of genetic and environmental factors, leading to challenges in accurately predicting and regulating its levels. In this study, we conducted a genome-wide association study (GWAS) on CA, employing six landmark models based on genome-wide variations including structural variants, insertions and deletions, and single nucleotide polymorphisms. The identification of 11 high-confidence candidate genes was further facilitated by leveraging linkage disequilibrium and causal variants associated with CA. The transcriptome data from candidate genes were examined, revealing higher correlations between the expression of certain candidate genes and changes in CA metabolism. Three CA-associated genes exerted a positive regulatory effect on CA accumulation, while the remaining genes exhibited negative impacts based on gene cluster and correlation analyses. The CA content of tomatoes is primarily influenced by improvement sweeps with minimal influence from domestication sweeps in the long-term breeding history, as evidenced by population differentiation and variants distribution. The presence of various causal variants within candidate genes is implicated in the heterogeneity of CA content observed among the tomato accessions. This observation suggests a potential correlation between the number of alternative alleles and CA content. This study offers significant function-based markers that can be utilized in marker-assisted breeding, thereby enhancing their value and applicability.

Monocyte-to-high-density lipoprotein cholesterol ratio and the risk of erectile dysfunction: a study from NHANES 2001-2004.

Background: The monocyte-to-high-density lipoprotein cholesterol ratio (MHR) has become a novel inflammation marker with a possible association with erectile dysfunction (ED); however, there are fewer studies exploring the association between MHR and ED. Aim: This study sought to explore the association between MHR and ED. Methods: This study population was drawn from participants in two 2-year cycles of the National Health and Nutrition Examination Survey (2001-2002 and 2003-2004). MHR was calculated as the ratio of monocyte count (103 cells/µL) to high-density lipoprotein cholesterol (mg/dL). The relationship between MHR and ED was explored using survey-weighted logistic regression models with MHR as a continuous variable and divided into tertiles (tertile 1 [T1]: <0.01; T2: 0.01-0.014; T3: >0.014). We also used a smooth curve fit (penalized spline method) to characterize the dose-response relationship between MHR and ED. In addition, subgroup analyses based on age, body mass index, smoking, hypertension, diabetes mellitus, and cardiovascular disease were performed to further analyze the data. Sensitivity analyses were also conducted to further assess the stability of the results. Outcomes: The main outcome measure was the difference in ED prevalence between MHR levels. Results: A total of 1361 participants were enrolled, with 513 (T1), 438 (T2), and 410 (T3) participants in the 3 MHR groups. After adjusting for all potential covariates, survey-weighted logistic regression analyses showed a significant association between MHR and ED (odds ratio [OR], 1.96; 95% confidence interval [CI], 1.26-3.05). When MHR was used as a categorical variable, the adjusted OR for ED prevalence increased significantly with increasing MHR after adjusting for all potential covariates (T3 vs T1: OR, 2.14; 95% CI, 1.29-3.55). The dose-response curves showed that the prevalence of ED increased with increasing MHR. Clinical Implications: Easy to access and low cost, MHR is a convenient clinical tool that helps clinicians in the prevention and treatment of ED. Strengths and Limitations: The present study is the first to examine the association between MHR and ED nationally representative data. However, the study population was derived from a U.S. database, so the findings are limited to the U.S. population. Conclusion: Our study demonstrated that MHR levels were independently associated with ED and that ED patients had higher MHR levels, suggesting that MHR may be a valuable predictor for identifying people at higher risk for ED.

Prognostic significance and value of further classification of lymphovascular invasion in invasive breast cancer: a retrospective observational study.

PURPOSE: To investigate the prognostic significance of lymphovascular invasion in invasive breast cancer and the value of using specific vascular endothelial markers to further classify lymphovascular invasion. METHODS: We collected 2124 patients with invasive breast cancer who were hospitalized at the First Hospital of Dalian Medical University from 2012 to 2020. Statistical methods were used to investigate the relationship between lymphovascular invasion and clinicopathological characteristics of breast cancer, and the correlation between lymphovascular invasion on overall survival (OS) and disease-free survival (DFS) of various categories of breast cancers. Immunohistochemical staining of breast cancer samples containing lymphovascular invasion using specific vascular endothelial markers D2-40 and CD34 was used to classify lymphovascular invasion and to investigate the relationship between lymphovascular invasion and breast cancer progression. RESULTS: There was a high correlation between lymphovascular invasion and T stage, N stage and nerve invasion. Survival analyses showed that patients with lymphovascular invasion, especially luminal B, triple-negative, and Her-2 overexpression breast cancer patients, had poorer OS and DFS prognosis, and that lymphovascular invasion was an independent prognostic factor affecting OS and DFS in breast cancer. The immunohistochemical staining results showed that positive D2-40 staining of lymphovascular invasion was linked to the N stage and localized recurrence of breast cancer. CONCLUSION: Lymphovascular invasion is associated with aggressive clinicopathological features and is an independent poor prognostic factor in invasive breast cancer. Breast cancer localized recurrence rate and lymph node metastases are influenced by lymphatic vessel invasion. Immunohistochemical techniques should be added to the routine diagnosis of lymphovascular invasion.

Dysregulation of peripheral and intratumoral KLRG1+ CD8+T cells is associated with immune evasion in patients with non-small-cell lung cancer.

OBJECTIVES: Killer cell lectin like receptor G1 (KLRG1) is identified as a co-inhibitory receptor for NK cells and antigen-experienced T cells. The role of KLRG1 in immune regulation in patients with non-small cell lung cancer (NSCLC) remains poorly understood. MATERIALS AND METHODS: We measured the proportion and immune function of KLRG1+CD8+T cells derived from peripheral blood in patients with NSCLC by flow cytometry. Besides, using data from the gene expression profiles and single-cell sequencing, we explored the expression and immune role of KLRG1 in tumor tissues of patients with NSCLC. We further determined the prognostic value of KLRG1 in terms of overall survival (OS) in NSCLC patients. RESULTS: We found that the proportion of KLRG1+CD8+T cells in peripheral blood significantly increased in patients with NSCLC as compared to those with benign pulmonary nodules and healthy donors. Peripheral KLRG1+CD8+T cell proportion was increased in elder subjects compared to that in younger ones, implying an immunosenescence phenotype. Moreover, the KLRG1+CD8+T cell levels were positively correlated with tumor size and TNM stage in the NSCLC cohort. In vitro stimulation experiments demonstrated that the KLRG1+CD8+T cells from peripheral blood expressed higher levels of Granzyme B and perforin than the KLRG1-CD8+ T cells. However, single-cell RNA sequencing data revealed that the KLRG1+CD8+ T cells were less infiltrated in tumor microenvironment and exhibited impaired cytotoxicity. The KLRG1 gene expression levels were significantly lower in tumor tissues than that in normal lung tissues, and were inversely correlated with CDH1 expression levels. Moreover, higher expression of CDH1 in tumor tissues predicted worse overall survival only in patients with KLRG1-high expression, but not in the KLRG1-low subset. CONCLUSION: This study demonstrates that KLRG1+CD8+T cells were associated with tumor immune evasion in NSCLC and suggests KLRG1 as a potential immunotherapy target.

Effect of γ-tACS on prefrontal hemodynamics in bipolar disorder: A functional near-infrared study.

OBJECTIVES: Transcranial alternating current stimulation (tACS) is a potential therapeutic psychiatric tool that has been shown to modulate clinical symptoms and brain function by inducing brain oscillations. However, direct evidence on the effects of gamma-tACS (γ-tACS) on Bipolar I Disorder (BD-I) is limited. In the present study we used functional near-infrared spectroscopy to explore prefrontal hemodynamic changes in BD-I patients receiving combined γ-tACS intervention in addition to pharmacological treatment. METHODS: Only 39 male patients with BD-I in the acute manic phase were included, and they were randomly divided into an intervention group (n = 18) and a control group (n = 21). The intervention group received γ-tACS treatment on a weekday for a total of 10 sessions in the right prefrontal cortex and left prefrontal cortex. All participants were pretested (baseline) and posttested (2 weeks after) with questionnaires to assess clinical symptoms and cognitive abilities, and with functional near infrared spectroscopy (fNIRS) to assess spontaneous cortical hemodynamic activities. RESULTS: Compared to the control group, the intervention group had greater increases in Montreal Cognitive Assessment (MoCA) scores, and greater decreases in Bech-Rafaelsen Mania Rating Scale (BRMS) scores. In the intervention group, functional connectivity (FC) was significantly greater in the left hemisphere. γ-tACS treatment resulted in a left hemispheric lateralization effect of resting state FC in BD-I patients, increasing the hemodynamic activity of the patient's left prefrontal cortex. CONCLUSIONS: γ-tACS can improve cognitive impairment and mood symptoms with BD-I patients in an acute manic episode by enhancing FC in the patients' left prefrontal cortex.

A novel strategy to induce penile erection during penile doppler ultrasound: oral sildenafil administration plus alprostadil injection.

OBJECTIVES: To evaluate the efficacy of a novel approach to achieve the optimal penile erection during the penile doppler ultrasound (PDU) examination, which was oral sildenafil combined alprostadil injection. MATERIALS AND METHODS: A total of 60 ED patients were enrolled in our prospective study, and they were randomly assigned to two group with different PDU order. The approaches assisted the PDU included two models, mode A meaning injection of 15 µg alprostadil and model B meaning oral sildenafil 100 mg plus injection of 15 µg alprostadil. The PDU parameters were measured continuously before induced erection, and 5, 10, 15, 20, 25 min. RESULTS: Each group included 30 ED patients with similar clinical characteristics. After pooling the results together, the PSV, EDV, and RI were all improved significantly, when adding the oral sildenafil administration to assist PDU. Also, the clinical response of oral sildenafil administration plus alprostadil injection was better than that in alprostadil injection alone (p = 0.016). The arterial ED were decreased from 31.67% to 15.00% with the P value 0.031, and the mixed ED was also decreased statistically (23.33% vs 8.33%, p = 0.024). CONCLUSION: Oral sildenafil administration plus alprostadil injection could improve the diagnostic accuracy of PDU.

Association between severe headache or migraine and erectile dysfunction in American adults: a cross-sectional of data study from the NHANES.

Currently, few studies have explored the relationship between severe headache or migraine and erectile dysfunction (ED). The aim of our study was to assess the association between severe headache or migraine and ED in adult men in the US from the National Health and Nutrition Examination Survey (NHANES). We used data from two separate NHANES datasets for the analysis: 2001-2002 and 2003-2004. We used multiple logistic regression, subgroup analysis, and sensitivity analyses to assess the relationship between severe headache or migraine and ED. From 2001 to 2004, 3117 adult male participants (582 ED patients, 2535 non-ED patients) were identified. Categorical and continuous variables are described using counts and frequencies and means and standard errors, respectively. For continuous variables, the two groups were compared using survey-weighted linear regression, while for categorical variables, survey-weighted chi-square tests were performed. Multiple logistic regression analysis showed that in the fully adjusted Model 3, severe headache or migraine was statistically significantly associated with ED (OR 1.51; 95% CI 1.14-1.99; P = 0.0036). In the fully adjusted Model 3, the results of the subgroup analysis showed that an age of 40-60 years (OR = 1.55, 95% CI: 1.05, 2.31, P = 0.029), a body mass index (BMI) < 25 kg/m2 (OR = 1.68, 95% CI: 1.02, 2.75, P = 0.0406) or ≥30 kg/m2 (OR = 1.65, 95% CI: 1.07, 2.54, P = 0.022), hypertension (OR = 1.78, 95% CI: 1.22, 2.60, P = 0.0029), diabetes mellitus (OR = 1.71, 95% CI: 1.26, 2.31, P < 0.001), CVD (OR = 1.54, 95% CI: 1.12, 2.10, P = 0.011) and hyperlipidemia (OR = 1.83, 95% CI: 1.07, 3.13, P = 0.028) were associated with ED with severe headache or migraine. This study demonstrated a statistically significant association between severe headache or migraine and ED among adult men in the US. However, the results of the study should be interpreted with caution due to the failure to assess the effects of depression and anxiety on the outcomes.

Application of Laser-Induced Acoustic Desorption for Molecular Rotational Resonance Spectroscopy.

Molecular Rotational Resonance (MRR) spectroscopy is a uniquely precise tool for the determination of molecular structures of volatile compounds in mixtures, as the characteristic rotational transition frequencies of a molecule are extremely sensitive to its 3D structure through the moments of inertia in a three-dimensional coordinate system. This enables identification of the compounds based on just a few parameters that can be calculated, as opposed to, for example, mass spectrometric data, which often require expert analysis of 10-20 different signals and the use of many standards/model compounds. This paper introduces a new sampling technique for MRR, laser-induced acoustic desorption (LIAD), to allow the vaporization of nonvolatile and thermally labile analytes without the need for excessive heating or derivatization. In this proof-of-concept study, LIAD was successfully coupled to an MRR instrument to conduct measurements on seven compounds with differing polarities, molecular weights, and melting and boiling points. Identification of three isomers in a mixture was also successfully performed using LIAD/MRR. Based on these results, LIAD/MRR is demonstrated to provide a powerful approach for the identification of nonvolatile and/or thermally labile analytes with molecular weights up to 600 Da in simple mixtures, which does not require the use of reference compounds. In the future, applications to more complex mixtures, such as those relevant to pharmaceutical research, and quantitative aspects of LIAD/MRR will be reported.

Chasing the heat: Unraveling urban hyperlocal air temperature mapping with mobile sensing and machine learning.

Many cities face unprecedented high temperatures with increasing extreme events. Heatwaves pose significant health risks, including cardiovascular diseases, heatstroke, and dehydration. Mapping urban near-surface air temperature (Tair) is crucial for understanding thermal exposure and addressing climate change. Previous studies relied on satellite-derived land surface temperature (LST) and stationary monitoring, but high spaio-temporal Tair mapping is still a challenge. This study optimized a mobile sensing scheme using an electric bicycle platform with environmental and image sensors, and deep learning captured local-scale urban factors. A spatio-temporal data fusion model that consisted of three parts, temporal trend extraction, locality analysis, and neighborhood effect analysis, generated hyperlocal Tair maps. The Results from Beijing demonstrated the effectiveness of the framework, achieving the lowest MAE of 0.02 °C. Optimized data collection and the new model achieved accurate temperature predictions and thermal exposure assessment. Efficiency enhanced sensing strategy was also proposed. The study highlights local-scale factors and spatio-temporal dependencies in addressing heatwaves and climate change impacts in urban areas.

Exciton polariton condensation from bound states in the continuum at room temperature.

Exciton-polaritons (polaritons) resulting from the strong exciton-photon interaction stimulates the development of novel low-threshold coherent light sources to circumvent the ever-increasing energy demands of optical communications1-3. Polaritons from bound states in the continuum (BICs) are promising for Bose-Einstein condensation owing to their theoretically infinite quality factors, which provide prolonged lifetimes and benefit the polariton accumulations4-7. However, BIC polariton condensation remains limited to cryogenic temperatures ascribed to the small exciton binding energies of conventional material platforms. Herein, we demonstrated room-temperature BIC polariton condensation in perovskite photonic crystal lattices. BIC polariton condensation was demonstrated at the vicinity of the saddle point of polariton dispersion that generates directional vortex beam emission with long-range coherence. We also explore the peculiar switching effect among the miniaturized BIC polariton modes through effective polariton-polariton scattering. Our work paves the way for the practical implementation of BIC polariton condensates for integrated photonic and topological circuits.

The Role of Solution Aggregation Property toward High-Efficiency Non-Fullerene Organic Photovoltaic Cells.

In organic photovoltaic cells, the solution-aggregation effect (SAE) is long considered a critical factor in achieving high power-conversion efficiencies for polymer donor (PD)/non-fullerene acceptor (NFA) blend systems. However, the underlying mechanism has yet to be fully understood. Herein, based on an extensive study of blends consisting of the representative 2D-benzodithiophene-based PDs and acceptor-donor-acceptor-type NFAs, it is demonstrated that SAE shows a strong correlation with the aggregation kinetics during solidification, and the aggregation competition between PD and NFA determines the phase separation of blend film and thus the photovoltaic performance. PDs with strong SAEs enable earlier aggregation evolutions than NFAs, resulting in well-known polymer-templated fibrillar network structures and superior PCEs. With the weakening of PDs' aggregation effects, NFAs, showing stronger tendencies to aggregate, tend to form oversized domains, leading to significantly reduced external quantum efficiencies and fill factors. These trends reveal the importance of matching SAE between PD and NFA. The aggregation abilities of various materials are further evaluated and the aggregation ability/photovoltaic parameter diagrams of 64 PD/NFA combinations are provided. This work proposes a guiding criteria and facile approach to match efficient PD/NFA systems.

Reversal of the Regioselectivity of Iron-Promoted Hydrogenation and Hydrohalogenation of gem-Difluoroalkenes.

The reaction regioselectivity of gem-difluoroalkenes is dependent on the intrinsic polarity. Thus, the reversal of the regioselectivity of the addition reaction of gem-difluoroalkenes remains a formidable challenge. Herein, we described an unprecedented reversal of regioselectivity of hydrogen atom transfer (HAT) to gem-difluoroalkenes triggered by Fe-H species for the formation of difluoroalkyl radicals. Hydrogenation of the in situ generated radicals gave difluoromethylated products. Mechanism experiments and theoretical studies revealed that the kinetic effect of the irreversible HAT process resulted in the reversal of the regioselectivity of this scenario, leading to the formation of a less stable α-difluoroalkyl radical regioisomer. On basis of this new reaction of gem-difluoroalkene, the iron-promoted hydrohalogenation of gem-difluoroalkenes for the efficient synthesis of aliphatic chlorodifluoromethyl-, bromodifluoromethyl- and iododifluoromethyl-containing compounds was developed. Particularly, this novel hydrohalogenation of gem-difluoroalkenes provided an effect and large-scale access to various iododifluoromethylated compounds of high value for synthetic application.

A Bidirectional Mendelian Randomization Study of Gut Microbiota and Cerebral Small Vessel Disease.

BACKGROUND: The causal nature of gut microbiota and cerebral small vessel disease (CSVD) is still obscure regardless of evidence supporting their observational correlations. OBJECTIVES: The primary objective of this research is to investigate the potentially pathogenic or protective causal impacts of specific gut microbiota on various neuroimaging subtypes of CSVD. METHODS: We obtained the latest summary-level genome-wide databases for gut microbiota and 9 CSVD traits. The univariable and multivariable Mendelian randomization (MR) studies were conducted to examine the possible causal link between exposure and outcome. Meanwhile, we conducted sensitivity analyses sequentially, containing the heterogeneity, pleiotropy, and leave-one-out analysis. Additionally, to clarify the potential bidirectional causality, the causality from CSVD traits to the identified gut microbiota was implemented through reverse MR analysis. RESULTS: The univariable MR analysis identified 22 genetically predicted bacterial abundances that were correlated with CSVD traits. Although conditioning on macronutrient dietary compositions, 2 suggestive relationships were retained using the multivariable MR analysis. Specifically, the class Negativicutes and order Selenomonadales exhibited a negative causal association with strictly lobar cerebral microbleeds, 1 neuroimaging trait of CSVD. There is insufficient evidence indicating the presence of heterogeneity and horizontal pleiotropy. Furthermore, the identified causal relationship was not driven by any single nucleotide polymorphism. The results of the reverse MR analysis did not reveal any statistically significant causality from CSVD traits to the identified gut microbiota. CONCLUSIONS: Our study indicated several suggestive causal effects from gut microbiota to different neuroimaging subtypes of CSVD. These findings provided a latent understanding of the pathogenesis of CSVD from the perspective of the gut-brain axis.

Association between overactive bladder and depression in American adults: A cross-sectional study from NHANES 2005-2018.

BACKGROUND AND AIM: Overactive bladder (OAB) and depression are both common disorders and there is research suggesting an association between the two, but there is a lack of studies with large samples. The aim of this study is to investigate the association between OAB and depressive symptoms. METHODS: We used data from the National Health and Nutrition Examination Survey (NHANES) database for the period 2005 to 2018. OAB was characterized by the Overactive Bladder Symptom Score (OABSS, score > 3) and depression was diagnosed by the Patient Health Questionnaire (PHQ-9, score ≥ 10). There were three models employed in our analysis: (1) Crude model was unadjusted; (2) Model 1 was adjusted for age, sex, race/ethnicity, educational level, and marital status; (3) Model 2 was adjusted for factors in Model 1 plus the remained potential covariates. We used survey-weighted logistic regression models to assess the association between OAB and depression. Subsequently, subgroup analyses and smoothed curve analyses were used to evaluate the reliability of the findings. RESULTS: Finally, a total of 6612 participants were included in our study, consisting of 1005 participants with diagnosis of OAB and 5607 participants without diagnosis of OAB. After adjusting for all covariates, there was a significant positive association between OAB and depression (OR: 2.89, 95 % CI: 1.91, 4.37). The severity of OAB was also positively associated with depression. Compared to participants without OAB, the fully adjusted ORs for depression were 2.76 (95 % CI: 1.64, 4.65) for those with mild OAB, 3.79 (95 % CI: 1.68, 8.55) for those with moderate OAB, and 5.21 (95 % CI: 1.39, 19.53) for those with severe OAB. CONCLUSIONS: This study revealed a strong association between OAB and depression and a progressive increase in the risk of depression as the severity of OAB (mild, moderate, and severe) increased. Therefore, it is important for clinicians to recognize the assessment of OAB symptoms in patients who are at risk for or have developed depressive symptoms, as well as the mental health of patients with OAB.

The diversity of inhibitory receptor co-expression patterns of exhausted CD8+ T cells in oropharyngeal carcinoma.

Exhausted CD8+ T cells (Texs) are characterized by the expression of various inhibitory receptors (IRs), whereas the functional attributes of these co-expressed IRs remain limited. Here, we systematically characterized the diversity of IR co-expression patterns in Texs from both human oropharyngeal squamous cell carcinoma (OPSCC) tissues and syngeneic OPSCC model. Nearly 60% of the Texs population co-expressed two or more IRs, and the number of co-expressed IRs was positively associated with superior exhaustion and cytotoxicity phenotypes. In OPSCC patients, programmed cell death-1 (PD-1) blockade significantly enhanced PDCD1-based co-expression with other IR genes, whereas dual blockades of PD-1 and cytotoxic T lymphocyte-associated protein 4 (CTLA-4) significantly upregulated CTLA4-based co-expression with other IR genes. Collectively, our findings demonstrate that highly diverse IR co-expression is a leading feature of Texs and represents their functional states, which might provide essential clues for the rational selection of immune checkpoint inhibitors in treating OPSCC.

Advances in epileptic network findings of hypothalamic hamartomas.

Hypothalamic hamartomas (HHs) are congenital developmental malformations located in the hypothalamus. They are associated with a characteristic clinical manifestation known as gelastic seizures (GS). However, the traditional understanding of HHs has been limited, resulting in insufficient treatment options and high recurrence rates of seizures after surgery. This is consistent with the network hypothesis of focal epilepsy that the epileptogenic zone is not only limited to HH but may also involve the distant cerebral cortex external to the HH mass. The epilepsy network theory, on the other hand, provides a new perspective. In this study, we aim to explore HH-related epilepsy as a network disease, challenging the conventional notion of being a focal lesional disease. We analyze various aspects of HHs, including genes and signaling pathways, local circuits, the whole-brain level, phenotypical expression in terms of seizure semiology, and comorbidities. By examining HHs through the lens of network theory, we can enhance our understanding of the condition and potentially identify novel approaches for more effective management and treatment of epilepsy associated with HHs.

Hypothalamic hamartomas (HHs) are unusual brain malformations present from birth in the hypothalamus region. They often lead to a distinctive type of seizures known as GSs. However, our current understanding of HHs is limited, and this has made it challenging to treat them effectively. Many patients continue to experience seizures even after surgery. We've typically considered HH-related epilepsy as a localized problem, but a new theory suggests that it may involve a network of brain areas. In our study, we aim to change the way we view HH-related epilepsy. Instead of thinking of it as a single lesion in the brain, we explore the idea that it's a network disease. To do this, we'll investigate various aspects of HHs, such as the genes and pathways involved, how different parts of the brain interact, the impact on the whole brain, the types of seizures experienced, and any related health issues. By looking at HHs through this network theory, we hope to gain a deeper understanding of the condition and potentially discover new ways to manage and treat epilepsy associated with HHs. This shift in perspective could offer hope to those living with HH-related epilepsy and lead to more effective treatments, ultimately improving their quality of life.

Kornblum Oxidation Reaction-Induced Collective Transformation of Lead Polyhalides for Stable Perovskite Photovoltaics.

The iodide vacancy defects generated during the perovskite crystallization process are a common issue that limits the efficiency and stability of perovskite solar cells (PSCs). Although excessive ionic iodides have been used to compensate for these vacancies, they are not effective in reducing defects through modulating the perovskite crystallization. Moreover, these iodide ions present in the perovskite films can act as interstitial defects, which are detrimental to the stability of the perovskite. Here, an effective approach to suppress the formation of vacancy defects by manipulating the coordination chemistry of lead polyhalides during perovskite crystallization is demonstrated. To achieve this suppression, an α-iodo ketone is introduced to undergo a process of Kornblum oxidation reaction that releases halide ions. This process induces a rapid collective transformation of lead polyhalides during the nucleation process and significantly reduces iodide vacancy defects. As a result, the ion mobility is decreased by one order of magnitude in perovskite film and the PSC achieves significantly improved thermal stability, maintaining 82% of its initial power conversion efficiency at 85 °C for 2800 h. These findings highlight the potential of halide ions released by the Kornblum oxidation reaction, which can be widely used for achieving high-performance perovskite optoelectronics.

Defective mutations of SlSGR1, SlPSY1 and MYB12 genes lead to formation of green ripe fruit in tomato.

Modern tomatoes produce colourful mature fruits, but many wild tomato ancestors form green or gray green ripe fruits. In this study, tomato cultivar 'Lvbaoshi' (LBS) that produces green ripe fruits was found to contain three recessive loci that were responsible for development of green ripe fruits. The colourless peel of LBS fruits was caused by a 603-bp deletion in the promoter of SlMYB12. The candidate genes of the remaining two loci were identified as Stay-Green 1 (SlSGR1) and Phytoene Synthase 1 (SlPSY1). A single nucleotide substitution was present in sgr1 of LBS, resulting in disruption of mRNA splicing and truncation of the translated protein. A retrotransposon was found in the first exon of the psy1 locus in LBS, leading to the absence of any detectable PSY1 transcripts. Co-suppression of SGR1 and PSY1 by RNA interference (RNAi) converted the pink fruits into green ripe fruits in transgenic plants. An amino acid change in PSY1 and a deletion in the promoter of SGR1 were identified in many wild tomatoes bearing green or gray ripe fruits. Transgenic lines expressing ProSGR1::SGR1 from Solanum pennellii failed to convert the purple-flesh fruits into the red-flesh fruits. Overexpression of PSY1 from green ripe fruit wild tomatoes in LBS plants could only partially rescue the green ripe fruit phenotype of LBS. Downregulation of the Ripening Inhibitor (RIN) gene in the green-flesh (gf) plants led to development of green ripe fruits. This work uncovers a novel regulatory mechanism by which SlMYB12, SlPSY1 and SlSGR1 regulate fruit colour in cultivated tomatoes and some wild tomato species.

Gas-phase F-atom migration reaction of deprotonated N-fluoroarenesulfonamides.

RATIONALE: Recently N-Fluoroarenesulfonamides (ArSO2 NHF) were found to be promising precursors for the preparation of N-fluorobenzenesulfonimide derivatives without applying F2 . However, very few studies have discussed the mass spectrometric behaviors of ArSO2 NHF with N-F structure. METHODS: In this article, we applied high-resolution electrospray ionization tandem mass spectrometry (HR-ESI-MS/MS) to study the effect on the mass spectrometric behaviors of ArSO2 NHF after the introduction of the F-atom to the N-atom of ArSO2 NH2 . RESULTS: High-resolution electrospray ionization mass spectrometry (HR-ESI-MS) experiments showed that ArSO2 NHF produced only good signals in negative ion mode, and the dominating product ion SO2 F- at m/z 83 was observed in all HR-ESI-MS/MS of ArSO2 NF- with different substituents in the Ar group. The formation of the product ion SO2 F- was proof of the gas-phase F-atom migration rearrangement from the N-atom to the S-atom in ESI-MS/MS of ArSO2 NF- . CONCLUSION: To fully explain the gas-phase reaction mechanism from ArSO2 NF- to SO2 F- , we studied the HR-ESI-MS/MS of deprotonated ArSO2 NHF and also performed theoretical calculations. Both results confirmed that ArSO2 NF- first underwent Smiles rearrangement to yield intermediate I (INT1) ArNFSO2 - , and then the F-atom of ArNFSO2 - migrated from the N-atom to the S-atom to form intermediate II (INT2) ArN- SO2 F, which finally dissociated to SO2 F- at m/z 83 with loss of a neutral nitrene (ArN). All these results showed that the formation of the product ion SO2 F- from ArSO2 NF- was a common and intrinsic gas-phase reactivity of ArSO2 NF- .

Tuning Pore Size in Graphene in the Angstrom Regime for Highly Selective Ion-Ion Separation.

Zero-dimensional pores spanning only a few angstroms in size in two-dimensional materials such as graphene are some of the most promising systems for designing ion-ion selective membranes. However, the key challenge in the field is that so far a crack-free macroscopic graphene membrane for ion-ion separation has not been realized. Further, methods to tune the pores in the Å-regime to achieve a large ion-ion selectivity from the graphene pore have not been realized. Herein, we report an Å-scale pore size tuning tool for single layer graphene, which incorporates a high density of ion-ion selective pores between 3.5 and 8.5 Å while minimizing the nonselective pores above 10 Å. These pores impose a strong confinement for ions, which results in extremely high selectivity from centimeter-scale porous graphene between monovalent and bivalent ions and near complete blockage of ions with the hydration diameter, DH, greater than 9.0 Å. The ion diffusion study reveals the presence of an energy barrier corresponding to partial dehydration of ions with the barrier increasing with DH. We observe a reversal of K+/Li+ selectivity at elevated temperature and attribute this to the relative size of the dehydrated ions. These results underscore the promise of porous two-dimensional materials for solute-solute separation when Å-scale pores can be incorporated in a precise manner.