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Li- and Mn-rich (LMR) cathode materials that utilize both cation and anion redox can yield substantial increases in battery energy density 1 – 3 . However, although voltage decay issues cause continuous energy loss and impede commercialization, the prerequisite driving force for this phenomenon remains a mystery 3 – 6 Here, with in situ nanoscale sensitive coherent X-ray diffraction imaging techniques, we reveal that nanostrain and lattice displacement accumulate continuously during operation of the cell. Evidence shows that this effect is the driving force for both structure degradation and oxygen loss, which trigger the well-known rapid voltage decay in LMR cathodes. By carrying out micro- to macro-length characterizations that span atomic structure, the primary particle, multiparticle and electrode levels, we demonstrate that the heterogeneous nature of LMR cathodes inevitably causes pernicious phase displacement/strain, which cannot be eliminated by conventional doping or coating methods. We therefore propose mesostructural design as a strategy to mitigate lattice displacement and inhomogeneous electrochemical/structural evolutions, thereby achieving stable voltage and capacity profiles. These findings highlight the significance of lattice strain/displacement in causing voltage decay and will inspire a wave of efforts to unlock the potential of the broad-scale commercialization of LMR cathode materials. Diffractive imaging of an important class of battery electrodes during cycling shows that lattice strain is a crucial yet overlooked factor that contributes to voltage fade over time.

Background Microplastics (MPs), which are smaller in size and difficult to degrade, can be easily ingested by marine life and enter mammals through the food chain. Our previous study demonstrated that following acute exposure to MPs, the serum testosterone content reduced and sperm quality declined, resulting in male reproductive dysfunction in mice. However, the toxic effect of long-term exposure to MPs at environmental exposure levels on the reproductive system of mammals remains unclear. Results In vivo, mice were given drinking water containing 100 μg/L and 1000 μg/L polystyrene MPs (PS-MPs) with particle sizes of 0.5 μm, 4 μm, and 10 μm for 180 consecutive days. We observed alterations in testicular morphology and reductions in testosterone, LH and FSH contents in serum. In addition, the viability of sperm was declined and the rate of sperm abnormality was increased following exposure to PS-MPs. The expression of steroidogenic enzymes and StAR was downregulated in testis tissues. In vitro, we used primary Leydig cells to explore the underlying mechanism of the decrease in testosterone induced by PS-MPs. First, we discovered that PS-MPs attached to and became internalized by Leydig cells. And then we found that the contents of testosterone in the supernatant declined. Meanwhile, LHR, steroidogenic enzymes and StAR were downregulated with concentration-dependent on PS-MPs. We also confirmed that PS-MPs decreased StAR expression by inhibiting activation of the AC/cAMP/PKA pathway. Moreover, the overexpression of LHR alleviated the reduction in StAR and steroidogenic enzymes levels, and finally alleviated the reduction in testosterone induced by PS-MPs. Conclusions PS-MPs exposure resulted in alterations in testicular histology, abnormal spermatogenesis, and interference of serum hormone secretion in mice. PS-MPs induced a reduction in testosterone level through downregulation of the LH-mediated LHR/cAMP/PKA/StAR pathway. In summary, our study showed that chronic exposure to PS-MPs resulted in toxicity of male reproduction under environmental exposure levels, and these potential risks may ring alarm bells of public health. Graphical abstract

Mitophagy alleviates neuronal damage after cerebral ischemia by selectively removing dysfunctional mitochondria. Phosphatase and tensin homolog (PTEN) induced putative kinase 1 (PINK1)/Parkin-mediated mitophagy is the most well-known type of mitophagy. However, little is known about the role of PINK1/Parkin-mediated mitophagy in ischemic tolerance induced by hypoxic postconditioning (HPC) with 8% O 2 against transient global cerebral ischemia (tGCI). Hence, we aimed to test the hypothesis that HPC-mediated PINK1/Parkin-induced mitochondrial ubiquitination and promotes mitophagy, thus exerting neuroprotection in the hippocampal CA1 subregion against tGCI. We found that mitochondrial clearance was disturbed at the late phase of reperfusion after tGCI, which was reversed by HPC, as evidenced by the reduction of the translocase of outer mitochondrial membrane 20 homologs (TOMM20), translocase of inner mitochondrial membrane 23 (TIMM23) and heat shock protein 60 (HSP60) in CA1 after HPC. In addition, HPC further increased the ratio of LC3II/I in mitochondrial fraction and promoted the formation of mitophagosomes in CA1 neurons after tGCI. The administration of lysosome inhibitor chloroquine (CQ) intraperitoneally or mitophagy inhibitor (Mdivi-1) intracerebroventricularly abrogated HPC-induced mitochondrial turnover and neuroprotection in CA1 after tGCI. We also found that HPC activated PINK1/Parkin pathway after tGCI, as shown by the augment of mitochondrial PINK1 and Parkin and the promotion of mitochondrial ubiquitination in CA1. In addition, PINK1 or Parkin knockdown with small-interfering RNA (siRNA) suppressed the activation of PINK1/Parkin pathway and hampered mitochondrial clearance and attenuated neuroprotection induced by HPC, whereas PINK1 overexpression promoted PINK1/Parkin-mediated mitophagy and ameliorated neuronal damage in CA1 after tGCI. Taken together, the new finding in this study is that HPC-induced neuroprotection against tGCI through promoting mitophagy mediated by PINK1/Parkin-dependent pathway.

Historically long accepted to be the singular root cause of capacity fading, transition metal dissolution has been reported to severely degrade the anode. However, its impact on the cathode behavior remains poorly understood. Here we show the correlation between capacity fading and phase/surface stability of an LiMn 2 O 4 cathode. It is revealed that a combination of structural transformation and transition metal dissolution dominates the cathode capacity fading. LiMn 2 O 4 exhibits irreversible phase transitions driven by manganese(III) disproportionation and Jahn-Teller distortion, which in conjunction with particle cracks results in serious manganese dissolution. Meanwhile, fast manganese dissolution in turn triggers irreversible structural evolution, and as such, forms a detrimental cycle constantly consuming active cathode components. Furthermore, lithium-rich LiMn 2 O 4 with lithium/manganese disorder and surface reconstruction could effectively suppress the irreversible phase transition and manganese dissolution. These findings close the loop of understanding capacity fading mechanisms and allow for development of longer life batteries. To unlock the potential of Mn-based cathode materials, the fast capacity fading process has to be first understood. Here the authors utilize advanced characterization techniques to look at a spinel LiMn 2 O 4 system, revealing that a combination of irreversible structural transformations and Mn dissolution takes responsibility.

To improve lithium-ion battery technology, it is essential to probe and comprehend the microscopic dynamic processes that occur in a real-world composite electrode under operating conditions. The primary and secondary particles are the structural building blocks of battery cathode electrodes. Their dynamic inconsistency has profound but not well-understood impacts. In this research, we combine operando coherent multi-crystal diffraction and optical microscopy to examine the chemical dynamics in local domains of layered oxide cathode. Our results not only pinpoint the asynchronicity of the lithium (de)intercalation at the sub-particle level, but also reveal sophisticated diffusion kinetics and reaction patterns, involving various localized processes, e.g., chemical onset, reaction front propagation, domains equilibration, particle deformation and motion. These observations shed new lights onto the activation and degradation mechanisms of state-of-the-art battery cathode materials. The battery performance at the cell level is an integration of contributions from many active particles. Here, the authors present a direct visualization of the active cathode particles that react heterogeneously and asynchronously by using coherent multi-crystal diffraction and optical microscopy.

Nocardia species are ubiquitous in natural environments and can cause nocardiosis. Trimethoprim-sulfamethoxazole has long been the monotherapy treatment of choice, but resistance to this treatment has recently emerged. In this study, we used microplate Alamar Blue assays to determine the antimicrobial susceptibility patterns of 65 standard Nocardia isolates, including 28 type strains and 20 clinical Nocardia isolates, to 32 antimicrobial agents, including 13 little studied drugs. Susceptibility to the most commonly used drug, trimethoprim-sulfamethoxazole, was observed in 98% of the isolates. Linezolid, meropenem, and amikacin were also highly effective, with 98%, 95%, and 90% susceptibility, respectively, among the isolates. The isolates showed a high percentage of resistance or nonsusceptibility to isoniazid, rifampicin, and ethambutol. For the remaining antimicrobials, resistance was species-specific among isolates and was observed in traditional drug pattern types. In addition, the antimicrobial susceptibility profiles of a variety of rarely encountered standard Nocardia species are reported, as are the results for rarely reported clinical antibiotics. We also provide a timely update of antimicrobial susceptibility patterns that includes three new drug pattern types. The data from this study provide information on antimicrobial activity against specific Nocardia species and yield important clues for the optimization of species-specific Nocardia therapies.

Choroidal nevus is the most common intraocular tumor, and most cases are benign and have no symptoms. However, choroidal nevus carries a low risk for transformation into melanoma, which is a highly aggressive and deadly cancer. In this case report, we present a male patient with blurred vision in his left eye for six months. Multimodal fundus imaging reported a large pigmented gray-brown choroidal lesion adjacent to the optic disc in his left eye, along with intraretinal and subretinal fluid (SRF) accumulation involving the macula and fluorescein leakage. Choroidal nevus was then diagnosed, and bevacizumab was given by intravitreal injection. After one month of bevacizumab treatment, spectral-domain optical coherence tomography showed a decrease in SRF. After four months of bevacizumab treatment, the patient suffered from more SRF and an elevated lesion in his left eye. During subsequent follow-up, the lesion continued to increase in size. Given the possibility of a malignant transformation of choroidal nevus into melanoma, transpupillary thermotherapy (TTT) was performed. The choroidal melanoma appeared to be necrotic at 10 months post-TTT. The patient's left eye was enucleated due to neovascular glaucoma 17 months post-TTT. Histopathologic examination showed diffuse infiltration of melanoma cells in the retina, choroid and optic nerve, and cell growth on the surface of the optic nerve papilla. Multiple treatment modalities, including external beam radiotherapy and systemic chemotherapy, were applied, but the patient eventually died due to metastasis. Patients with choroidal nevus should be managed with multimodal fundus imaging and be closely followed up due to the risk of transformation into a malignant melanoma. For cases with clinical and imaging features of malignant transformation, early intervention and long-term follow-up are required to achieve local disease control and vision preservation.

To examine the age and sex-specific associations of urine levels of six mono-phthalates with body size and fat distribution in Chinese children at puberty. Four hundred and ninety-three school-aged children (247 boys, 246 girls) were recruited. Obesity related anthropometric indices were measured and body fat proportion (BF%) was calculated. Spot urine samples were collected and phthalate monoesters were detected by an API 2000 electrospray triple quadrupole mass spectrometer (ESI-MS/MS). Associations between phthalate exposure and overweight/obesity measures and their trends were examined by multiple linear regression and Logistic regression analyses, respectively. Di-2-ethylhexyl phthalate (DEHP) metabolites and monobutyl phthalate (MBP) were found to be the most detectable chemicals. In 8-10 years (yrs) group, concentrations of MEHP and MBP were significantly higher in girls than those in boys. However, concentrations of all phthalate monoesters, except for MEP and MEHP, in 11-13 yrs boys were significantly higher than those in girls. After adjusting for confounders including puberty onset, urinary concentrations of MBP and sum of low molecular-weight phthalate metabolites (∑LMP) were positively associated with boys' obesity in a concentration-effect manner, while concentrations of MEHP, MEHHP and sum of DEHP metabolites (∑MEHP) were negatively associated with girls' obesity. Associations between phthalate exposure levels and BMI z-score changes were age- and sex-specific in school-age children. There are age and sex-specific concentration-effect associations between phthalate exposure and fat distribution in Chinese children. Urinary phthalate levels in 11-13 yrs boys were about 30 percent higher than those in girls, and ∑MEHP levels in younger boys (<10 yrs) were significantly higher than those in elder boys (>10 yrs). Associations were positive for MBP and ∑LMP with both BMI z-score and fat distribution in boys >10 years of age, and negative for ∑MEHP with fat distribution in girls <10 years of age.

China is one of the countries with a high incidence of esophageal squamous cell carcinoma (ESCC). At present, the main treatment method for ESCC is surgery combined with chemotherapy and radiotherapy, and the efficacy of drug therapy is not ideal. Cyclin-dependent kinase inhibitors (CDKi) have shown amazing efficacy in treating some types of cancer, especially breast cancer, but their therapeutic effects on ESCC are limited. In the present study, we found that the CDK inhibitor palbociclib could successfully arrest cells in the G0/G1 phase but did not inhibit the proliferation of some types of ESCC cells. Further experiments revealed that activation of the PI3K‒AKT pathway was key for palbociclib resistance. Therefore, we investigated the potential of combining palbociclib with the novel PI3K inhibitor PIK75 to inhibit the growth of ESCC cell lines and xenograft tumors. The combined use of palbociclib and PIK75 synergistically inhibited the expression of the cell cycle proteins CCNE1, CDC6, and CDC25A, as well as the abnormal activation of PIK3CA and AKT phosphorylation. The combination of these two drugs synergistically inhibited tumor cell cycle progression and promoted apoptosis in vitro and in vivo, which provides a promising idea for the treatment of ESCC in the future.

Objective This study evaluated the accuracy and comprehensiveness of responses generated by ChatGPT-4o and DeepSeek regarding commonly asked questions about myopia. Methods Thirty myopia-related questions spanning six clinical domains were submitted to both chatbots. Three medical professionals independently rated each response for accuracy and comprehensiveness. Inter-rater reliability was assessed using Fleiss’ Kappa, and Shapiro-Wilk tests were conducted to examine normality in rating distributions. Statistical comparisons were performed using the Chi-square test, with significance set at p  < 0.05. Results DeepSeek outperformed ChatGPT-4o in overall accuracy, with significantly more responses rated as “Good” ( p  < 0.0001). Both models demonstrated high comprehensiveness scores when accuracy was rated “Good,” though performance declined in treatment-related queries, particularly regarding commercial products like DIMS lenses. Fleiss’ Kappa values indicated poor inter-rater agreement (DeepSeek: = 0.106; ChatGPT-4o: = − 0.0221), and normality tests showed non-normal score distributions ( p  < 0.0001 across domains). Conclusion Both ChatGPT-4o and DeepSeek can deliver useful responses to myopia-related questions, though limitations remain in areas requiring up-to-date, region-specific treatment information. DeepSeek’s stronger performance suggests that localized LLMs may offer competitive advantages. Ongoing refinement, regular data updates, and domain-specific fine-tuning are essential for improving the reliability of AI chatbots in clinical communication.