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Synergistic Dual‐Interface Engineering in Perovskite Solar Cells via Chloramine Hydrochloride Molecular Bridges
Abstract High‐performance perovskite solar cells (PSCs) require synergistic passivation strategies to address defects at the electron transport layer (ETL)/perovskite interface, impacting both efficiency and long‐term stability. This study introduces chloramine hydrochlorides (CAHs) – 2‐Chloroethylamine Hydrochloride (CEA), Bis(2‐chloroethyl)amine Hydrochloride (BCEA), and Tris(2‐Chloroethyl)Amine Hydrochloride (TCEA) – as bifunctional molecular bridges to simultaneously passivate defects at both ETL (SnO 2 ) and perovskite interfaces while controlling crystallization. Density functional theory calculations showed that TCEA forms strong Sn─Cl bonds, enhancing Sn⁴ + coordination. In situ characterization revealed that TCEA accelerated perovskite formation, suppressed PbI 2 , and promoted larger grains, thus minimizing grain boundary defects. This leads to an improved electron extraction efficiency, prolonged hot‐carrier cooling, and a champion power conversion efficiency (PCE) of 25.25% (compared to 23.64% for controls), with negligible hysteresis and 90% PCE retention after 1000 h under ambient conditions. This study establishes a universal molecular design strategy for dual‐interface engineering in high‐efficiency and stable PSCs.
Effect of random terms on the shape of dendrites analyzed by the phase-field model
In this study, we focus on random terms with a significant effect on the calculation time and the sidebranch structure of dendrites. We quantitatively evaluate the effect of the random terms on dendrites by changing the term introduced into the evaluation equation, the distribution of the random term, and variance. We introduced the terms: χ and ∇·q. In the phase-field equation, we use χ to represent interfacial noise. In the heat conduction equation, we use ∇·q to represent thermal noise. We compare the results of calculation using only χ with those using only ∇·q and analyze the effect of each random term introduced on the shape of dendrites. In terms of the probability distribution for generating random numbers, the uniform and Gaussian distributions are used for comparison. The magnitude of the noise Fu, which controls the variance of noise, is used with 3 or 4 patterns of values to the extent that the calculation results do not diverge. Each value of Fu differs by a factor of 10. Sidebranch length, contour length, and area are used as indices for evaluating dendrites. The succinonitril is used for comparing the simulation and experimental results for dendrites to design the optimal random number model. On the basis of the introduced terms, we clarify that each term requires a different order of the variance. The probability density function of random numbers does not affect the shape of dendrites. On the other hand, the calculation time which is used the random numbers following the uniform distribution is more than twice as fast as when using random numbers that follow a Gaussian distribution. The variance of a random term has the greatest effect on the shape of dendrites.
NbGa <sub>2</sub> S <sub>4</sub> (S <sub>2</sub> ): A Rare Linear [S <sub>2</sub> ] <sup>2−</sup> Coordination to Niobium Resulting in Simultaneously Large SHG Effect and Giant Birefringence
Abstract We report a novel niobium thiogallate, NbGa 2 S 4 (S 2 ), featuring a rare linear [S 2 ] 2− coordination to niobium, which simultaneously exhibits a strong second harmonic generation effect [1.5 × benchmark AgGaS 2 (AGS)], a high laser‐induced damage threshold (5.7 × AGS), and a giant birefringence (0.29 at 2 µm, the largest among all reported 3D chalcogenides). Theoretical studies reveal that the polarizability anisotropy and hyperpolarizability are significantly enhanced due to the unique alignment of [S 2 ] 2− dimer within the crystal lattice. Additionally, the compound demonstrates exceptional chemical bond flexibility, which leads to significantly reduced thermal anisotropic expansion, one order of magnitude smaller than that of the benchmark AGS. These findings provide valuable insights for the design of next‐generation functional materials with tailored optical and thermal characteristics.
Incidental findings on non-contrast abdominal computed tomography in an asymptomatic population: Prevalence, economic and health implications
Introduction Increasing use of low-dose abdominal computed tomography (CT) scans in clinical diagnostics and research offers high sensitivity for kidney stones with minimal radiation exposure. However, due to reduced specificity, incidental findings potentially lead to unnecessary follow-up, financial burden, and psychological distress. Gaps of knowledge remain regarding the prevalence of incidental findings and their financial and psychological consequences. This study investigates the prevalence of incidental findings in asymptomatic participants undergoing low-dose non-contrast CT scans and their economic and psychological sequelae. Methods We conducted a retrospective, multicentric observational study using data from the assessment for the control group of the Swiss Kidney Stone Cohort (SKSC). Low-dose non-contrast CT scans were analyzed for incidental findings, cost and psychological impact. Statistical analyses evaluated participant characteristics, financial and psychological consequences. Results 229 participants underwent low-dose non-contrast CT scans, with 112 correctly completing the psychological questionnaires. The mean age was 42.9 years, and 56.3% were male. Incidental findings were observed in 47.2% (n = 108) of participants, with 16.6% having multiple findings. Kidney-related findings were the most prevalent, accounting for 35% of all findings. Of the incidental findings, 37.9% were classified as “incidentalomas” by the American College of Radiology (ACR) guidelines, and 15.7% of participants had findings that warranted follow-up according to radiology reports. In terms of costs, follow-up procedures, including imaging, consultations, and surgeries, incurred a total expense of 44’988 CHF, averaging 1967 CHF per participant and 2’999 CHF per incidental finding requiring follow-up. Surgical interventions were necessary for three participants, with individual costs reaching up to 35’208 CHF. Psychological assessment revealed that emotional distress and level of concern significantly differed across resilience levels and categories of CT findings. Participants with high resilience demonstrated lower emotional distress and concern, while those with CT findings requiring follow-up exhibited higher distress. Emotional distress was significantly greater in participants with follow-up findings compared to those without. Conclusions Low-dose non-contrast abdominal CT scans often reveal incidental findings. Follow-up tests and procedures incurred significant financial costs, occasionally even leading to unnecessary surgical or non-surgical interventions. Psychological assessments showed increased anxiety in participants requiring follow-up, particularly those with low resilience. Our findings highlight the need for improved management, patient information, and consideration of economic and psychological impacts of incidental findings in clinical research and routine in the future.
Simultaneous Boosting of Second Harmonic Generation and Circularly Polarized Luminescence in Chiral Hybrid Metal Halides Through Enhanced Octahedral Distortion
Abstract Chiral hybrid metal halides (HMHs), characterized by their non‐centrosymmetric crystal structures and exceptional photophysical properties, are promising for second‐order nonlinear and linear optics, including second‐harmonic generation (SHG) and circularly polarized luminescence (CPL). However, chiral HMHs with simultaneously strong SHG response and efficient CPL still present a challenge, due to the distinct structural and electronic requirements of these properties. Here, we report a halogen substitution strategy within inorganic octahedra to modulate the crystal structure and simultaneously enhance both SHG and CPL properties. Three pairs of chiral Sb‐based HMHs are synthesized: ( R / S ‐MBA) 2 IASbBr 6 (MBA = α‐methylbenzylammonium, IA = imidazole, abbreviated as R / S ‐SbBr 6 ), ( R / S ‐MBA) 2 IASbBr 2.8 Cl 3.2 ( R / S ‐SbBr 2.8 Cl 3.2 ), and ( R / S ‐MBA) 2 IASbCl 6 ( R / S ‐SbCl 6 ). The gradual halogen substitution from R / S ‐SbBr 6 to R / S ‐SbCl 6 significantly enhances the structural chirality of inorganic octahedra, resulting in a strong SHG response intensity of 1.4 × KDP and a high luminescence dissymmetry factor of 3.82 × 10 −2 . The combination of SHG and CPL performance outperforms that of previous chiral HMHs. Experimental results and theoretical calculations indicate that these enhancements originate from gradually increased octahedral distortions induced by halogen substitution. This work establishes a structural optimization strategy for advancing high‐performance SHG and CPL in chiral HMHs, paving the way for their broader photonic applications.
Historical availability of arable land affects contemporaneous female labor and health outcomes
We contribute to the understanding of mechanisms underlying deep-rooted gender norms by exploring the link between the historical availability of arable land and contemporary gender outcomes. We argue that an abundance of arable land in historical times, i.e., pre-industrial period, required more workers in the fields resulting in norms where women worked and contributed from outside the home as well. Consequently, these societies emphasized women’s health due to its positive effect on their productivity in the fields. Moreover, this economic contribution provided women greater bargaining power in the allocation of intrahousehold resources. The historical avail- ability of arable land for a nation is measured as the weighted mean of the shares of its constituent ethnic groups’ ancestral lands suited to cereal agriculture. Consistent with these arguments, we show that countries with more ancestral arable land have higher female labor force participation rates and better health outcomes, measured by maternal mortality ratio and female-male life expectancy gap. We then illustrate the ‘persistence of norm’ mechanism, by showing that ancestral arable land measured at the district level is positively associated with individual-level attitudes regarding women’s participation in the labor market.
Molecule‐Cooperative Strategy for Dopant‐Free Hole Transporting Layer toward Fully Printed High‐Performance Perovskite Solar Cell Modules
Abstract Enabling large‐area deposition of dopant‐free organic hole transport layers (HTLs) with high reproducibility and uniformity is crucial for fully printed n‐i‐p perovskite solar cell (pero‐SC) modules. However, typical polymer hole transport materials (HTMs), with non‐Newtonian fluid characteristics, show shear rate‐dependent viscosity during the printing process, whereas blade‐coated small‐molecule HTLs often exhibit unfavorable assembly behavior and solute random distribution caused by molecular aggregation and low viscosity; these factors impose challenges on blade‐coating of high‐quality large‐area HTL films. Here, we designed a dopant‐free small molecule BDT‐MB with high mobility and further proposed a molecular cooperative (MC) strategy by combining with polymer D18. The mechanism was clearly clarified that the pre‐aggregated polymer D18 acted as a “seed crystal” to induce preferential face‐on orientation of small molecule BDT‐MB through intermolecular C─H···π interaction. This strategy not only suppresses the unfavorable assembly behavior of small molecular HTMs but also overcomes the solute random distribution by tuning the solution with high and constant viscosity. It facilitates printing large‐area dopant‐free HTLs with high uniformity and ordered fiber‐like morphology. The resultant small‐area pero‐SCs (0.062 cm 2 ) and large‐area fully printed modules (15.64 cm 2 ) both achieved record power conversion efficiencies (PCEs) of 24.46% (certified at 24.30%) and 21.04%.
Zero-shot performance analysis of large language models in sumrate maximization
Large language models have revolutionized the field of natural language processing and are now becoming a one-stop solution to various tasks. In the field of Networking, LLMs can also play a major role when it comes to resource optimization and sharing. While Sumrate maximization has been a crucial factor for resource optimization in the networking domain, the optimal or sub-optimal algorithms it requires can be cumbersome to comprehend and implement. An effective solution is leveraging the generative power of LLMs for such tasks where there is no necessity for prior algorithmic and programming knowledge. A zero-shot analysis of these models is necessary to define the feasibility of using them in such tasks. Using different combinations of total cellular users and total D2D pairs, our empirical results suggest that the maximum average efficiency of these models for sumrate maximization in comparison to state-of-the-art approaches is around 58%, which is obtained using GPT. The experiment also concludes that some variants of the large language models currently in use are not suitable for numerical and structural data without fine-tuning their parameters.
Elucidating the Correlation Between the Redox Potential, Spin State, and Crystal Structure in a Series of Ferrous Complexes with Redox‐Active Ligands
Abstract Accurately predicting the spin crossover (SCO) temperature ( T 1/2 ) in spin crossover compounds remains a significant challenge due to their extreme sensitivity to minor variations in ligand and crystal structure. In this study, we uncover a critical link between the redox potential of ligands and SCO behavior within Hofmann‐type clathrates {Fe(R‐pbpy⁺)₂[μ₂‐M(CN)₄]₂} (R = electron‐donating or electron‐withdrawing groups, M = Pd or Pt). Through precise tuning of the ligands' electronic properties, we establish a correlation between redox potential, space group, and SCO temperature, explained by an adaptation of Marcus theory of electron transfer. These findings not only provide a deeper understanding of the factors governing SCO behavior but also present a promising strategy for the rational design of SCO materials with tailored properties.
Small Molecule‐Induced Alterations of Protein Polyubiquitination Revealed by Mass‐Spectrometric Ubiquitome Analysis
Abstract Small molecules that alter protein ubiquitination are emerging as therapeutics due to their ability to modulate targets previously deemed undruggable. These compounds comprise PROTACs, molecular glue degraders, and DUB inhibitors, among others. However, methods for the proteome‐wide monitoring of compound‐induced changes in protein polyubiquitination, which may also detect non‐degradative modifications, are lacking. Here, we report the utilization of polyubiquitin enrichment coupled to mass spectrometry to monitor small molecule‐induced changes in cellular protein ubiquitination. We established enrichment through tandem ubiquitin binding entities (TUBEs) following semi‐denaturing cell lysis and devised an elution protocol compatible with downstream LC‐MS/MS analysis. We demonstrate the broad applicability of the workflow by assessing ubiquitination changes induced by a PROTAC, a p97 inhibitor, and deubiquitinase inhibitors. Application of the assay to compounds inhibiting the deubiquitinase USP7 revealed the induction of non‐degradative ubiquitination on the E3 ligase UBE3A. Collectively, we established a versatile proteomics method to facilitate the direct investigation of cellular polyubiquitination, with high relevance for the identification and characterization of protein degraders, stabilizers, and other molecules with ubiquitin‐mediated bioactivity.
Correction: Farmland increases Indian crested porcupine occupancy in Parsa-Koshi complex, Nepal
Features of drug addiction treatment programs in Atlantic Canada that help (or not) with access and retention: A qualitative study
Access to government-funded addiction treatment programs can reduce harms experienced by people who use substances (PWUS). There is some research on what features (e.g., policies and practices) of treatment programs help or do not help with access; however, not much is known about program directors’ and physicians’ perspectives of these features in Atlantic Canada. One-on-one semi-structured qualitative interviews were conducted with program directors and physicians working in government-funded addiction treatment programs in Atlantic Canada in 2021. Interview questions focused on perspectives of program features that helped or not with access and retention, including perspectives on changes due to COVID-19. Data were coded and analyzed using grounded theory techniques to develop themes and subthemes. Fourteen individuals were interviewed. They identified several features that helped (e.g., quick access) or did not help (e.g., wait times) with access and retention. Participants shared some features that changed due to COVID-19, including some that helped (e.g., virtual services) and did not (e.g., limited program spaces). Participants suggested changes that could support access and retention, including better linkages to mental health supports. This paper highlights program directors’ and physicians’ perspectives on how program features inform access and retention in Atlantic Canada. Findings on changes made during COVID-19 point to the need to maintain the changes that were helpful and implement additional changes to better support access for more PWUS. To support the implementation and sustainability of these changes, more resources must be invested.
Acidic Nitrate Electroreduction with Ultrahigh Energy Efficiency
Abstract Ammonia (NH 3 ) is an important feedstock for industry, an ideal energy carrier, and a perspective storage media for hydrogen. Recently, electrochemical nitrate (NO 3 −) reduction under acidic conditions has received considerable attention but it suffers from limited efficiency especially under low NO 3 − concentration. Here, we report an in situ formed positively charged polyethyleneimine‐modified Cu under acidic conditions as a catalyst‐electrolyte interface (CEI) for electrochemical NO 3 − reduction to NH 3 . Such CEI can effectively accumulate NO 3 − anions via static interactions and accelerate *NO hydrogenation to *NOH by weakening *NO intermediate adsorption on Cu site, thereby facilitating NO3−‐to‐NH 3 conversion. Such CEI delivers an increased NH 3 Faradaic efficiency (FE) of 83.5% and an impressive half‐cell energy efficiency (EE) of 37.1% in 10 mM NO 3 − solution (pH = 1). The NH 3 FE and EE can further increase to 90.2% and 44.1% in 0.5 M NO 3 −, respectively. The high EE of CEI surpasses previously reported catalyst performances for NO 3 − reduction. Finally, we demonstrate the feasibility of a novel NO 3 −‐furfural battery, showcasing a self‐power electrocatalytic system capable of simultaneously treating NO 3 − pollutants, generating value‐added NH 3 and upgrading biomass. This work offers valuable insights into the construction of a CEI to enhance the efficiency of NH 3 synthesis.
The impact of antimicrobial stewardship interventions on surgical antibiotic prophylaxis guidelines compliance in a teaching hospital in Ghana
Background Inappropriate use of surgical antibiotic prophylaxis (SAP) to prevent surgical site infections (SSIs) is noted to be a major contributor of antimicrobial resistance (AMR) globally, including Ghana. This study sought to assess the impact of antimicrobial stewardship (AMS) interventions on SAP guideline compliance and other surgical outcomes including SSI and length of hospital stay. Method This was a nine-month quasi-experimental (before- and after-intervention) study. Four months’ medical records of 150 obstetric and gynecological surgery patients were collected both before (baseline) and after the implementation of AMS interventions in a teaching hospital in Ghana. The interventions included education on the hospital SAP guidelines and feedback of the baseline survey results to the surgical team. An adapted data collection sheet was used to collect medical records of the included patients. A descriptive analysis was performed, a Pearson’s chi-square test and a two-sample Wilcoxon (Mann-Whitney U) rank-sum test were used to assess the impact of the interventions. Results Most (n = 220/300, 73.33%) of the patients were between the ages of 24–44 years, and the commonest surgery was an emergency caesarean section (n = 92/300, 30.67%). After the AMS interventions, there was a significant improvement in guideline compliance due to appropriate antibiotic choice (p = 0.001). duration (p < 0.001), and the volume of consumption of SAP (p < 0.001). There were no significant changes in the timing of administration (p = 0.636), SSI rate (p = 0.054), and the length of hospital stay (p = 0.161). Conclusion Our study showed positive impact of the two AMS interventions on SAP guideline compliance based on the choice and duration of prescription, and reduction of the volume of antibiotic utilization, but not on the timing of administration. This did not worsen the SSI rate and patient length of stay. Hospitals in Ghana and beyond are encouraged to optimize SAP use and prevent rising AMR rates by implementing appropriate educational programmes and dissemination of audit findings.
Pilot study of cerebrospinal fluid biomarkers reveals inflammatory changes in patients with paranoid schizophrenia
Abstract Paranoid schizophrenia is a severe mental illness with both positive and negative symptoms. Currently, the role of peripheral and central inflammation is increasingly suspected as possible factor in the pathogenesis of schizophrenia. This retrospective, monocentric pilot study investigated 35 patients (15/35 female) diagnosed with paranoid schizophrenia after exclusion of possible underlying neuroinflammatory disorders to assess for inflammatory changes of the cerebrospinal fluid (CSF) and associated signs of neurodegeneration. Kappa free light chains (KFLC), a panel of 21 cyto- and chemokines, and neurofilament light chains (NFL) as surrogate parameters for neuro-inflammation and -degeneration were determined in patients with paranoid schizophrenia as well as age- and sex-matched inflammatory (n = 35) and non-inflammatory controls (n = 40). Patients with paranoid schizophrenia exhibited significantly higher intrathecal synthesized fractions of KFLC than non-inflammatory controls. KFLC-positive patients with paranoid schizophrenia had significantly higher NFL concentrations in CSF than KFLC-negative patients according to Reiber´s diagram. NFL concentrations in CSF of patients with paranoid schizophrenia were associated with illness duration, frequency of psychotic episodes, and amount of antipsychotic treatment attempts. This pilot study highlights inflammatory changes in the CSF among a specific subgroup of patients with paranoid schizophrenia, positively correlating with elevated NFL levels in CSF.