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Hydrogen Atom Transfer-Mediated <i>N</i>-Heterocycles Dehydrogenation Coupled with the CO₂ Photoreduction to Syngas

LSWOA: An enhanced whale optimization algorithm with Levy flight and Spiral flight for numerical and engineering design optimization problems

Whale Optimization Algorithm (WOA) suffers from issues such as premature convergence, low population diversity in the later stages of iteration, slow convergence rate, low convergence accuracy, and an imbalance between exploration and exploitation. Thus, an enhanced Whale Optimization Algorithm (LSWOA) based on multiple strategies is proposed, aiming to overcome the limitations of the canonical WOA. The performance of the canonical WOA is improved through innovative strategies: first, an initialization process using Good Nodes Set is introduced to ensure that the search starts from a higher-quality baseline; second, a distance-based guided search strategy is employed to adjust the search direction and intensity by calculating the distance to the optimal solution, which enhances the algorithm’s ability to escape local optima; and lastly, LSWOA introduces an enhanced spiral updating strategy, while the enhanced spiral-enveloping prey strategy effectively balances exploration and exploitation by dynamically adjusting the spiral shape parameters to adapt to different stages of the search, thereby more accurately updating the positions of individuals and improving convergence speed. In the experimental section, we validate the efficiency and superiority of LSWOA by comparing it with outstanding metaheuristic algorithms and excellent WOA variants. The experimental results show that LSWOA exhibits significant optimization performance on the benchmark functions with various dimensions. Additionally, LSWOA is tested on seven engineering design optimization problems, and the results demonstrate that it performs excellently in these application scenarios, effectively solving complex optimization problems in different dimensions and showing its potential for a wide range of applications in real-world engineering challenges.

Bench-Stable Carbamoylzinc Pivalates for Modular Access to Amides, Ureas, and Thiocarbamates

One health approach unravels worrying antimicrobial resistance patterns: A cross-sectional study in Kisii, Kenya

Background Antimicrobial resistance (AMR) is a major public health challenge, particularly in Sub-Saharan Africa, where diagnostic and surveillance capacities are limited. Enterobacterales significantly contribute to AMR, with environmental reservoirs facilitating transmission between humans, animals, and the environment. Methods This study investigated the prevalence and antimicrobial susceptibility of selected Enterobacterales in human, water, animal feces, and soil samples in Kenya. A cross-sectional study including 200 patients with gastrointestinal symptoms was conducted at Kisii Teaching and Referral Hospital and surrounding areas. AMR testing was performed using the disk diffusion method. Results A total of 365 samples were collected: 200 human and 55 each of water, animal feces, and soil specimens from the homesteads of patients with resistant isolates. 343 isolates were obtained (Escherichia coli: 280/343 [81.6%], Salmonella spp.: 28/343 [8.2%], Klebsiella spp.: 25/343 [7.3%], Shigella spp.: 10/343 [2.9%]). A significant proportion of isolates exhibited AMR, particularly to piperacillin-tazobactam (up to 87%) and ampicillin (up to 79%). Resistance to piperacillin-tazobactam in E. coli was the highest, observed in humans (100/139, 71.9%), water (42/49, 85.7%), animal feces (9/46, 19.6%), and soil (33/46, 71.7%). Almost half (45%) of the human isolates showed ESBL production or resistance to imipenem, with water, animal feces, and soil samples, revealing similar resistance patterns. Resistance to chloramphenicol (71.7% vs 20.1%; p &lt; 0.001) and third-generation cephalosporins were higher among animal and environmental isolates (animal feces: cefotaxime – 25/46, 54.3%; ceftazidime – 27/46, 58.7%) as compared to human isolates (cefotaxime – 40/139, 28.8%; ceftazidime – 28/139, 20.1%) (p &lt; 0.001). In human isolates, the most prevalent genes were blaTEM (53/187, 28.3%), blaOXA-48 (43/187, 23.0%), blaSHV (32/187, 17.1%), and blaCTXM-15 (41/187, 21.9%); in animal isolates, blaCTXM-8 (11/55, 20.0%), blaVIM (8/55, 14.5%), and blaTEM (8/55, 14.5%) were most detected; while in soil and water isolates, blaCTXM-8 was the most common (10.9% and 9.1% respectively). Conclusion Shared resistance patterns across human, animal, and environmental samples highlight interconnected AMR pathways. These findings reinforce the need for a One Health approach through integrated AMR surveillance and interventions.

Molecular Engineering of Interlayer Exciton Delocalization in 2D Perovskites

Lung and abdominal ultrasound accuracy for tuberculosis: An Indian prospective cohort study

Background Tuberculosis (TB) diagnosis remains a challenge, particularly in low-resource settings. Point-of-care ultrasound (POCUS) has shown promise, but most studies focus on HIV-infected populations. In the case of TB, data on lung ultrasound (LUS) are sparse. Therefore, this study evaluates the diagnostic accuracy of lung and abdominal ultrasound for TB diagnosis in an Indian tertiary care hospital Methods We prospectively enrolled adults with presumed TB and performed comprehensive ultrasound assessments. Accuracy of individual and combined sonographic findings was evaluated against a robust reference standard (mycobacterial culture and PCR). Comparators were C-reactive protein at a cut-off of 5mg/l and chest x-ray (CXR). A multivariable model incorporating clinical and ultrasound findings was explored using generalized mixed models and a random forest approach. (Trial registry DRKS00026636). Findings Among 541 participants, 102 (19%) were diagnosed with TB and 1% were HIV-positive. The “Focused Assessment with Sonography for HIV-associated TB” (FASH) demonstrated moderate sensitivity (51%) and specificity (70%). Consolidations &lt;1 cm on LUS showed high sensitivity (93%) but low specificity (16%) and were also seen in non-TB lung infections and other conditions like bronchial asthma and COPD. Accuracy of larger (≥1 cm) consolidations (72% sensitive, 55% specific) on LUS was comparable with CXR suggesting possible TB (81% sensitive, 58% specific). Predictive modeling suggests moderate diagnostic performance (AUC = 0.79). Interpretation In our study, POCUS did not meet WHO targets for a stand-alone facility-based screening test. Nevertheless, diagnostic accuracy for some findings is comparable to CXR and could be integrated into diagnostic algorithms to improve TB screening where CXR cannot reach. Future research should explore artificial intelligence to enhance TB-POCUS accuracy and accessibility, as was previously reported for CXR. Research in context Prior to this study, lung ultrasound (LUS) for TB had been assessed in only a few studies, limited by uncertain sonographic characterization of TB-related findings, lack of consistent terminology, and small numbers of participants with confirmed non-TB diagnoses to determine specificity for TB. Studies evaluating Focused assessment with sonography for HIV-associated tuberculosis (FASH) almost exclusively included HIV-infected individuals and demonstrated moderate sensitivity and specificity. However, varying study designs and reference standards limit broader generalization of their findings. Our prospective study from a TB-endemic setting (India) recruited 541 predominantly HIV-negative participants with presumed TB. This is the largest cohort to date assessing LUS, FASH, and additional ultrasound findings for TB diagnosis. Our study demonstrates that no single ultrasound finding alone, or even in combination, reaches the accuracy targets of the target product profile for a facility-based screening test (triage) proposed by WHO. FASH accuracy in our study aligned with previously reported data in HIV-negative participants but was less specific in HIV-positive participants. The accuracy of additional ultrasound items of LUS and FASH was comparable to chest x-ray (CXR). In summary, this study demonstrates accuracy of ultrasound for TB diagnosis, backed by a robust study design and using a comprehensive reference standard and CXR comparator for LUS. Modelling suggests that an algorithmic approach combining ultrasound and clinical findings may be of highest value to inform risk of TB and guide further testing to confirm the diagnosis of TB. Other use cases of POCUS, which may aid clinical decision making in the assessment of disease severity, sampling strategy, and monitoring, should be evaluated by future studies. These should also focus on the accuracy of POCUS in people living with HIV and children, as well as evaluate POCUS more broadly as part of a diagnostic algorithm and by using artificial intelligence to improve the yield of TB-POCUS.

Quantifying Interface-Dependent Active Sites Induced by Topotactic Exsolution for CO₂ Electrolysis

Correction: Canadian natural science graduate stipends lie below the poverty line

When π–π Stacking Outcompetes Hydrogen Bonding: Pre-Reactive Intermediates in the Furan–Acrolein Diels–Alder Reaction

A novel Leishmania infantum reference strain for gene editing and the study of visceral leishmaniasis

Parasites of the Leishmania donovani complex are responsible for visceral leishmaniasis, a vector-borne disease transmitted through the bite of female phlebotomine sand flies. As well as the human hosts, these parasites infect many mammals which can serve as reservoirs. Dogs are particularly important reservoirs. Transmission is widespread across Asia, Africa, the Americas, and the Mediterranean basin, including South of France. Visceral leishmaniasis poses a fatal threat if left untreated. Research into the pathophysiology of this neglected disease is of prime importance, as is the development of new drugs. In this study, we evaluated the growth, differentiation, and macrophage infectivity of four L. donovani complex strains and identified L. infantum S9F1 (MHOM/MA/67/ITMAP263, clone S9F1) as a well-adapted strain for genetic engineering studies. We present here the genome sequence and annotation of L infantum S9F1 T7 Cas9, providing the scientific community with easy access to its genomic information. The data has been integrated into the LeishGEdit online resource to support primer design for CRISPR-Cas9 experiments. We now aim to make this strain widely available to foster studies of visceral leishmaniasis.

Thiophenol-Catalyzed Radical Hydroformylation of Unactivated Sterically Hindered Alkenes

<i>N</i>-Heterocyclic Selone-Catalyzed [2σ + 2π] Cycloaddition of Bicyclo[1.1.0]butanes via Photoredox Radical Buffer

Development, optimization, and preliminary evaluation of a novel artificial intelligence tool to promote patient health literacy in radiology reports: The Rads-Lit tool

Radiology reports are an integral part of patient medical records; however, these reports often contain complex medical terminology that are difficult for patients to comprehend, potentially leading to anxiety, misunderstanding, and misinterpretation. The development of user-friendly instruments to improve understanding is thus critically important to enhance health literacy and empower patients. In this study, we introduce a novel artificial intelligence (AI) interface, the Rads-Lit Tool, which can simplify radiology reports for patients using natural language processing (NLP) techniques. This manuscript presents the development process, methodology, and results of the Rads-Lit Tool, demonstrating its potential to simplify radiology reports across various examination types and complexity levels. Our findings highlight that patient-facing AI-driven tools can enhance patient health literacy and foster improved patient-provider communication in radiology.

Catalytic Oxidative Ligand Transfer of Rh-Carbynoids and Alkyl Iodides

Who continued travelling by bus in different periods of COVID-19? A data-driven analysis from Shanghai, China

The COVID-19 pandemic has caused unprecedented disruptions to individual travel behavior in the public transport (PT) system. To attract more travelers to use PT in the post-pandemic era, it is necessary to understand the heterogeneity of travel behavior changes among various user segments and across different pandemic periods. This paper presents a two-step analysis framework for discovering the inter-segment and intra-segment changes in travel patterns of PT users based on ticketing data. The framework is then applied to the case of Jiading bus transit in Shanghai, China during the COVID-19 pandemic in 2022. The results suggest that commuters are more vulnerable to the impacts of the pandemic than non-commuters, with a considerable tendency to give up commuting by bus or even permanently discontinue bus usage after the lockdown in Shanghai. Only 17.7% of bus users maintain their travel patterns after the lockdown, with a few observable sub-segments of users comprising students and employees. The findings in this study aid PT operators in achieving a better recovery in the post-pandemic era and enhance their preparedness to tackle challenges in demand management for potential crises.

Dynamic Equilibrium between the Fluorescent State of Tryptophan and Its Cation-Electron Ion Pair Governs Triplet State Population

Funerary practices of cremation at the megalithic societies of South-Eastern Iberia: The cemetery of Los Milanes

The archaeological excavations undertaken at the Chalcolithic necropolis of Los Milanes have revealed a previously unknown variability in funerary practices in the south-eastern Iberia. For the first time, a megalithic tomb housed a large funerary deposit (28,740 bone fragments) of exclusively cremated human bone remains. For a comprehensive characterization of the funerary ritual, a cutting-edge multi-proxy approach has been undertaken including the osteological study of cremated bone remains, radiocarbon chronology, Fourier-Transform Infrared spectroscopy in Attenuated Total Reflectance mode (FTIR-ATR), and carbon, oxygen and strontium isotope analyses. As a result, the cremation ritual consisted of multi-depositional events of at least 21 individuals chronologically concentrated in the first quarter of the third millennium, principally in the 28th century cal BC. The absence of charcoal/ashes in the funerary chamber and the underrepresentation of anatomical regions such as lower limb and trunk suggest that the cremation took place elsewhere and the bone remains were carefully collected and placed as secondary burial depositions. Different proxies including colour patterns, heat‐induced fractures, the presence of cyanamide in calcined bones would also suggest the cremation of principally complete corpses, burnt soon after death. The ritual of cremation coexisted with inhumations during the third millennium cal BC, suggesting a variability in the body manipulation that previously went unnoticed. Unlike inhumations, through cremation, bodies would have been reduced until being indistinguishable, transforming radically the nature of human beings and their ontological status.

Tiny flier could soar through the mesosphere powered only by light

Orbital-Resolved Stepwise Single-Electron Capture Dynamics in a Single Fullerene

Assessing Knowledge, Uptake and Factors associated with cervical cancer screening among women in selected communities of Wakiso district in Uganda: A population-based study

Background Uganda has the highest prevalence and incidence of cervical cancer in the East African region, with 80% of women diagnosed at advanced stage when survival is minimal. Literature on uptake of cervical cancer screening is limited in Uganda and thus womens’ knowledge and uptake of cervical cancer screening in the general population remains unknown. This study examined this gap of knowledge among women aged 25–65 years, across rural, urban and semi urban communities in a Ugandan district to inform design of targeted future cervical cancer screening programs in the country. Methods This descriptive cross-sectional study was conducted in Wakiso district, Uganda in May 2024 among 783 eligible women. Face-to-face interviews were conducted. Uptake of cervical cancer screening (outcome of interest) was dichotomously (yes/no) assessed. Knowledge of cervical cancer disease was assessed using the AWACAN validated tool, knowledge of cervical cancer screening was assessed using a set of ten (10) questions adapted from previous studies elsewhere, and all were measured on a Likert scale. Univariate, bivariate, and multivariable Poisson regression models with robust variance were performed using Stata software version 17. Results Respondents’ median age was 31 years (IQR 27–39 years). Majority (89.5%, 701/783) had heard of cervical cancer, and 90.6% (635/701) were aware of screening. Median knowledge score on signs and symptoms, risk factors and cervical cancer screening was 8.0 (IQR = 5–10), 8.0 (IQR = 5–11) and 7.0 (IQR = 4–10) respectively, and 54.3% had high knowledge about cervical cancer screening. Uptake of cervical cancer screening was 33.4%. Living in urban areas (aPR = 1.41, 95% CI: 1.05–1.88), being the ages 40–49 years (aPR = 1.76, 95% CI: 1.36–2.27), 50 years and above (APR = 2.16, 95% CI: 1.53–3.04), smoking (aPR = 1.39, 95% CI: 1.05–1.86), partner involvement (aPR = 2.61, 95% CI: 2.12–3.21), high knowledge about cervical cancer screening (aPR = 3.29, 95% CI: 2.35–4.60), and living with HIV (aPR = 1.66, 95% CI: 1.66–2.13) were significantly associated with higher uptake of cervical cancer screening among women in this setting. Conclusion Knowledge of cervical cancer screening was high, but the uptake of cervical cancer screening was lower than the recommended population coverage by WHO and Uganda national guidelines. There is need to improve accessibility to cervical cancer screening, increase nationwide cervical cancer awareness campaigns focusing on high-risk age groups and design targeted, tailored, culturally and socially sensitive interventions for young women aged 25–39 years to improve cervical cancer screening in Uganda.