A family of $n\times n$ matrices over a field $\mathbb {F}$ is irreducible if it has no common nontrivial invariant subspace, and minimally irreducible if it is irreducible but has no proper irreducible subfamily. If $\mathbb {F}$ is algebraically closed and $n\ge 2$, a minimally irreducible family has at most $2n-1$ elements. We show that for complex $n\times n$ matrices, $n\ge 3$, a family of minimally irreducible (i) matrix units, (ii) rank one projections, (iii) unicellular matrices and (iv) orthoatomic matrices has k elements where respectively (i) $n\le k\le 2n-2$, (ii) $k=n$, (iii) $2\le k\le n-1$ and (iv) $2\le k\le n-1$. All of the values of k in these ranges are attained. If $n=2$, each such minimally irreducible family has $2$ elements.

A new species of spionid polychaete from the coastal waters of southwest India, Trochochaeta chakara sp. nov., is described and illustrated. Adults are common on Alappuzha mud banks (locally known as Chakara) off the coast of Kerala. They live in silty tubes in soft sediment and are characterized by the presence of two pairs of red eyes, caruncle extending to end of chaetiger 1, heavy falcate spines in neuropodia of chaetigers 2 and 3 (those in chaetiger 3 much stronger and darker), capillary chaetae in notopodia of chaetigers 1, 3–10, frayed heavy spines in neuropodia of chaetigers 4–13, hirsute capillaries in neuropodia from chaetiger 14, lateral interneuropodial membranes from chaetiger 14, one pair of ventral papillae on each chaetiger from chaetigers 14–16, bundles of acicular spines in notopodia from chaetigers 50–52, and small pygidium with up to six pairs of short cirri. This is the third species of Trochochaeta described and found in the Indian Ocean, including T. orissae (Fauvel, 1932) and T. cirrifera (Hartman, 1975).

To solve the problems of precise operation and real-time interaction during the spraying process of industrial robots, a new spraying method based on digital twin technology is proposed. In view of the limitations of traditional spraying processes in complex geometric shape processing, spraying uniformity control, and operational flexibility, this study built a highly simulated virtual environment based on digital twin and human–machine collaboration technology, allowing operators to guide the robot in real time for precise spraying operations. The use of multisensor fusion technology achieves a high degree of consistency between the physical and virtual environments, ensuring that the system can maintain high-precision spraying on complex workpiece surfaces. The experimental designed spraying tasks for different geometric shapes and evaluated the performance of the system’s interactive spraying method in terms of real-time feedback guidance and path planning. The results show that the proposed method significantly improves the accuracy and efficiency of the spraying process, especially showing obvious advantages when processing complex geometric workpieces, and provides a new technical approach for future high-precision manufacturing.

After the Zero COVID policy ended on December 7, 2022, ~90% of mainland Chinese were infected in a COVID-19 wave. This systematic review synthesized research estimating excess mortality during that wave in mainland China. We searched seven databases in May 2024 and updated our search in July–August 2025. Peer-reviewed research (Chinese or English), published since January 1, 2023, estimating excess deaths in the COVID-19 wave post-Zero-COVID was included. Risk of bias was assessed using a modified Newcastle-Ottawa Scale. Two authors independently conducted abstract screening, full-text review, data extraction, and risk-of-bias assessment. Seven articles were included. Two studies analysed the death records of a town and a district in Shanghai, estimating the excess mortality rates of 153.6% and 174.3%, respectively. Using indirect methods, four studies estimated national excess mortality (range: 0.71–1.87 million). Another study estimated excess mortality in Taiyuan. Studies used diverse methods to estimate excess deaths, resulting in widely varying and uncertain estimates. Choice of reference period, seasonality, and other factors affect expected mortality estimates.

Suicide is a significant global public health concern, particularly among adolescents, with substantial implications for economies, societies and individuals’ mental well-being. Understanding its patterns and intention and psychosocial determinants in a given context can suggest potential intervention points. This population-based cross-sectional study aimed to document suicidal ideas, behaviors and intensity among youths aged 14 to 25 in the Nairobi metropolitan area and associated socio-economic position, demographic indicators and potential intervention points. A diverse sample of 1,972 participants was recruited from urban and peri-urban settings within the Nairobi metropolitan area. Data analysis included descriptive statistics, chi-square tests and logistic regression. Our findings confirm a high prevalence of suicidal ideas and behavior in the youth (19.9% and 3.6%, respectively), with very few significant differences between the urban and peri-urban areas. The severity of suicidal ideation and behavior reported methods and reasons, and the socio-demographic profile of participants, point to multiple potential intervention targets. These findings ought to be used to design, manage and evaluate suicide prevention programs.

Khasi nightshade (Solanum khasianum C.B. Clarke) is a perennial poisonous weed in tropical and subtropical regions that seriously threatens the development of grasslands. For a high-risk invasive weed, a comprehensive understanding of its seed germination characteristics is important for predicting its spread and developing effective management strategies. However, the impact of various abiotic factors on the germination of S. khasianum is not clear. This study first explored the effects of temperature, light, pH, osmotic stress, salt stress, high-temperature pretreatment, and burial depth on the germination of S. khasianum. Seeds germinated at constant temperature of 30, 33, 35, and 38 C, and the germination rate (GR) ranged from 10% to 94%. The optimum germination temperature was 35 C, while germination was completely inhibited at 25 or 40 C. The germination of S. khasianum was greatly promoted by alternating light and darkness (16/8, 12/12, 8/16 h), but was not sensitive to the time change of photoperiod. The GRs were more than 70% in the pH range of 4 to 10, and a strongly acidic environment was more suitable for germination. The GR gradually decreased with the osmotic potential from 0 to −0.2 MPa, and no germination occurred at −0.4 MPa. Accordingly, germination was also low in sodium chloride (NaCl) solution with concentrations higher than 60 mM. Seeds of S. khasianum were not tolerant to high temperature; GR decreased significantly after exposure to 40 C for 5 min, and it decreased to 3% at 120 C. The emergence rate was the highest (93%) when the seeds were buried on the soil surface, while seedlings hardly appeared when the burial depth was more than 2 cm. This study revealed the possible adaptive mechanism of invasive S. khasianum and will contribute to the effective prediction of its spread and management in grasslands.

Since the first report of erythromycin-resistant Bordetella pertussis (B. pertussis) in Arizona in 1994, macrolide-resistant strains have emerged worldwide, threatening pertussis control. This systematic review and meta-analysis aimed to quantify the prevalence and temporal trends of this resistance. Four databases (PubMed, Embase, Cochrane Library, Web of Science) were searched for studies on B. pertussis antimicrobial susceptibility through December 2024. Among 57 included studies (1994–2024), pooled resistance rates (breakpoint ≥32 mg/L) were: erythromycin 21% (95% CI 11–32%), azithromycin 25% (95% CI 12–40%), clarithromycin 15% (95% CI 4–30%), and clindamycin 49% (95% CI 28–70%). Subgroup analyses by country, year, and test method are presented. No trimethoprim/sulfamethoxazole (STX) resistance was reported. Six Japanese isolates showed high-level nalidixic acid resistance (MIC >256 mg/L). Seventy-seven studies contributed to MIC90 data for carbapenems, tetracyclines, aminoglycosides, quinolones, macrolides, cephalosporins, and others. Selected penicillins and intravenous third-generation cephalosporins demonstrated strong in vitro activity, suggesting alternative treatment options. Macrolide-resistant B. pertussis has increased significantly over the past decade. Due to the high burden of antibiotic resistance in China, enhanced surveillance is warranted, while continued monitoring in other countries also remains necessary.

This article recovers the international thought of Jón Ólafsson—an Icelandic journalist, transatlantic migrant, and settler colonialist—to illuminate how visions of world order were articulated from the Northern European periphery at the fin de siècle. While scholars have emphasized the rise of Anglo-Saxonist ideas—particularly the notion of a racial-imperial union between the United States and Britain—as central to late nineteenth-century reimaginings of global politics, little attention has been paid to how such ideas were adapted beyond the English-speaking world itself. Tracing how Ólafsson reworked this paradigm for a transnational audience, the article argues that he expanded the imagined boundaries of the Angloworld through appeals to what he saw as Teutonic whiteness. The result was what might be termed a ‘Teutonisphere’: a vision of racial solidarity illustrating how great-power narratives were refracted, appropriated, and creatively reconfigured by intellectuals in peripheral regions. Cast as pristine exemplars of the Teutonic race, Icelanders were imagined as ideal agents to rejuvenate Anglo-Saxon colonization from the US frontier and Canadian prairies to the South African veldt.

Henry John Temple, third Viscount Palmerston, the ebullient Victorian foreign secretary and prime minister, is no stranger to historians; few stones in his life have been left unturned. One exception is Palmerston’s relationship with the Devonshire borough of Tiverton, which he represented in Parliament for thirty years. Palmerston’s biographers have traditionally downplayed the significance of the Tivertonians and this article offers a more sophisticated approach, by relating popular politics to the nascent historiographical subfields of celebrity and memory. It finds that, during Palmerston’s lifetime, the celebrity status that he used Tiverton to cultivate became a source of civic pride and a pillar of the borough’s identity. Then, after Palmerston’s death, the politics of celebrity became intertwined with the politics of memory. Control of the political space that Palmerston’s legacy occupied became a prerequisite for electoral success, as political debates mutated into bitter arguments over which faction had the better claim to his legacy. This article therefore seeks to illuminate new ways of reading Palmerston and to contribute to the growing body of work on Victorian celebrities and the political uses of the Victorian past.

This study aimed to evaluate the agreement between three body composition devices and dual-energy X-ray absorptiometry (DXA) in assessing segmental body composition among healthy Iranian adults. This comparative study recruited 62 healthy adults (33 men and 29 women) from Tehran, Iran, using a convenience sampling approach. Socio-demographic data were collected, and segmental body composition was assessed using several devices, including the InBody 770, Anea bioelectrical impedance analysis (BIA), Tanita BC-418 and DXA. Agreement between DXA and the BIA devices was evaluated using Lin’s concordance correlation coefficient (CCC). Additionally, Bland–Altman plots and mean percentage error were applied to assess the consistency between the two methods. The Anea, InBody 770 and Tanita BC-418 devices showed strong correlation with DXA for all segmental measurements (r ≥ 0·74, P < 0·05). Moderate agreement (CCC: 0·90 ≤ CCC < 0·95) with the DXA method was found for some segments using the Anea (trunk fat mass, arms fat-free mass, legs fat-free mass and trunk fat-free mass) and the InBody 770 (trunk lean body mass and trunk fat mass) devices. The estimation of legs fat mass was the least accurate across all BIA devices. Furthermore, subgroup analyses showed that the BIA devices provided more precise results in men and in individuals with a BMI < 25·00 kg/m2. The Anea BIA and InBody 770 devices show relatively acceptable validity for segmental body composition assessment. More research is needed to confirm these findings.

This article argues that Marcus Argentarius, the witty and obscene epigrammatist from the Garland of Philip, juxtaposes his brand of erotic, sympotic poetry with the learned astronomical poetry of Aratus in two poems that utilise imagery of the cosmos and constellations, Anth. Pal. 5.105/7 G–P and Anth. Pal. 9.270/26 G–P. I review the (recognised) obscene double entendres in Anth. Pal. 5.105/7 G–P, compare that poem to Philodemus’ own ‘dirty astronomy’ epigram (Anth. Pal. 11.318/28 G–P/31 Sider), and then suggest that Anth. Pal. 9.270/26 G–P also contains obscene double entendres, which equate Argentarius’ lyre-playing with masturbation, and masturbation with the writing of amusing, erotic epigrams.

Delaying cover crop termination until planting (i.e., planting green) in no-till production systems is likely to mediate the fate of herbicides that provide soil-residual activity. There is currently limited knowledge of how the interaction between physiochemical properties of cover crop residues and sorption properties of herbicides influence the wash-off potential of residual herbicides from cover crop residues in a planting green scenario. We conducted field- and laboratory-based experiments using herbicide wash-off assay methods to evaluate the interaction between lignin (%) of cereal rye (Secale cereale L.) and herbicide lipophilicity (Kow) on wash-off potential across herbicide application timings. We contrasted herbicides with intermediate lipophilicity (atrazine, pyroxasulfone, and S-metolachlor) to less lipophilic (mesotrione) and highly lipophilic (pendimethalin) herbicides. Wash-off was greater for atrazine and pyroxasulfone than for mesotrione and S-metolachlor when applied into living cereal rye. Pendimethalin had the least wash-off potential. When pendimethalin was applied into fresh to aged cereal rye residues (0 to 84 d after termination), wash-off was below the detection threshold. Wash-off of mesotrione, pyroxasulfone, and atrazine declined as lignin (%) in cereal rye residues increased, whereas a positive relationship between S-metolachlor recovery and lignin (%) was observed. Results of our study partially support the hypotheses that (1) herbicide lipophilicity, measured via log Kow values, can be a useful indicator of wash-off potential among residual herbicides used in cover crop systems; and (2) wash-off potential declines as cover crop residues age within herbicide application windows.

Following Entman’s observation that policy frames define social problems, diagnose causes and suggest remedies, we examined the strategies that 12 U.S. governors (from states matched according to population size and density, demographic composition, per capita incomes, geographic proximity, and COVID-19 incidence) used to frame COVID-19 policy agendas. After scraping the governors’ statements about COVID-19 from press releases issued from January 2020 to May 2023 (N = 14,629), we leveraged ChatGPT (GPT) to identify and assess the intensity of public health, economic stability, and civic vitality frames. Subsequent analysis explored differences in the framing strategies according to the governors’ political party and gender. In the process, this study underscores the importance of AI prompt engineering to realize GPT’s transformative potential to facilitate communication research by efficiently identifying and assessing the content of policy frames.