For any integers x and y, let $(x, y)$ and $[x, y]$ stand for the greatest common divisor and the least common multiple of x and y, respectively. Let $a,b$ and n be positive integers, and let $S=\{x_1, \ldots , x_n\}$ be a set of n distinct positive integers. We denote by $(S^a)$ and $[S^a]$ the $n\times n$ matrices having the ath power of $(x_i,x_j)$ and $[x_i,x_j]$, respectively, as the $(i,j)$-entry. Bourque and Ligh [‘On GCD and LCM matrices’, Linear Algebra Appl. 174 (1992), 65–74] showed that if S is factor closed (that is, S contains all positive divisors of any element of S), then the GCD matrix $(S)$ divides the LCM matrix $[S]$ (written as $(S)\mid [S]$) in the ring $M_n({\mathbb Z})$ of $n\times n$ matrices over the integers. Hong [‘Divisibility properties of power GCD matrices and power LCM matrices’, Linear Algebra Appl. 428 (2008), 1001–1008] proved that $(S^a)\mid (S^b)$, $(S^a)\mid [S^b]$ and $[S^a]\mid [S^b]$ in the ring $M_{n}({\mathbb Z})$ when $a\mid b$ and S is a divisor chain (namely, there is a permutation $\sigma $ of order n such that $x_{\sigma (1)}\mid \cdots \mid x_{\sigma (n)}$). In this paper, we show that if $a\mid b$ and S is factor closed, then $(S^a)\mid (S^b)$, $(S^a)\mid [S^b]$ and $[S^a]\mid [S^b]$ in the ring $M_{n}({\mathbb Z})$. The proof is algebraic and p-adic. Our result extends the Bourque–Ligh theorem. Finally, several interesting conjectures are proposed.

Since the early 1950s, national statisticians have regarded unpaid work as non-economic, excluding it from GDP. Feminist scholars argue this exclusion reflects a gender-biased view of progress that renders women’s non-market productivity invisible. As what gets measured drives policy priorities and resource allocation, breastfeeding highlights the need to account for women’s unpaid care work in economic statistics. This paper advances the Beyond GDP agenda by demonstrating how market-derived prices can improve the measurement and recognition of women’s lactation labour. We first trace the historical displacement of breastfeeding by commercial formula and identify key economic drivers. Next, we review critiques of GDP and debates over including non-market household services in the UN’s System of National Accounts. We then present novel estimates of breast milk’s economic value in selected countries. Our analysis shows that existing market prices can robustly proxy for breastfeeding work, correcting GDP’s gender bias and realigning policy priorities. Including human milk production in core economic indicators not only reflects its true contribution but also promotes women’s and children’s rights and supports sustainable development through comprehensive true-cost accounting.

The present study describes a new Ditylenchoides species, isolated from Meknès, Morocco, during nematode surveys conducted to investigate the biodiversity of plant-parasitic nematodes in Mediterranean olive groves and adjacent patches of natural vegetation. Application of integrative taxonomical approaches clearly verified that it is a new species designated herein as Ditylenchoides morocciensis sp. nov., also representing the first report of the genus in Morocco. The new species is parthenogenetic, characterised by a short body 460 (373–528 μm); stylet delicate, relatively short, 8.7 (8.0–9.0) μm long with rounded basal knobs; six lines in the lateral fields; median bulb of pharynx oval, muscular and valvate; secretory-excretory pore located at the level of basal pharyngeal bulb region; vulva located at 79.9 (76.9–81.3) % of body length; relatively long post-vulval uterine sac 29.1 (20.0–39.0) μm; and a subcylindrical tail 24.4 (22.0–28.0) μm long, with a bluntly rounded tip. The results of molecular analysis of D2-D3 28S rRNA, ITS rRNA, partial 18S rRNA, and cytochrome oxidase c subunit 1 (COI) gene sequences support for the new species status and clearly separated D. morocciensis sp. nov. from all other species within Ditylenchoides. Phylogenetic analyses of ribosomal markers (D2-D3 28S rRNA and partial 18S rRNA) of this study confirms that Ditylenchoides is a monophyletic genus, clearly separated from other genera within Anguinoidea.

We developed a compact, ultra-wideband radar demonstrator for measurements of snow thickness. We designed the radar to be capable of reconfigurable operation over Ku- and S/C bands, and with a size, weight, and power compatible with a C-3 class unmanned aircraft system (UAS). We implemented the radar’s radio frequency frontend using low-cost laminate materials and employed 3D printed antennas for an inexpensive implementation. To demonstrate its performance and capabilities, we first conducted a series of laboratory tests, followed by tests of opportunity in Antarctica using a sled-based setup. Next, we integrated the radar demonstrator into an Aurelia X6 Pro system and completed a series of local flight tests over areas including grass-covered land and a wooded section with different seasonal foliage conditions. Lastly, we used our UAS-borne radar test bed to map seasonal snow accumulation to a depth close to ∼30 m in Greenland from 100-m altitude. In this paper, we offer a succinct description of the radar test bed electronics, a discussion of laboratory tests and integration considerations, and present sample results from various field scenarios.

The reproductive efficiency of dairy cows decreases significantly in hot climates. Exposure to heat stress causes damage to different stages of the reproductive cycle including a decrease in the quality of oocytes. Antioxidant supplementation has been introduced as one of the main approaches to alleviate the effects of free radical damage associated with heat stress. Gamma-oryzanol (ORY), a component of rice bran oil, is introduced as a novel antioxidant. As a supplement of culture media for maturation, the effect of ORY on the development of heat-shocked bovine cumulus–oocyte complexes was evaluated in this study. At the end of maturation in vitro using the heat-shock model, a higher proportion of metaphase II oocytes (0.78 ± 0.03 vs 0.42 ± 0.03) and lower metaphase I and germinal vesicle breakdown (0.10 ± 0.02 vs 0.38 ± 0.03) were recorded for the treated group (N = 205) in comparison with the control (N = 203) (P < 0.05). Moreover, the treatment exerted upregulation of NRF2, SOD, CAT and GPX transcripts in matured oocytes and GPX in CCs, along with a considerable increase in the cleavage (0.52 ± 0.04 vs 0.33 ± 0.03) and total blastocyst rates (0.30 ± 0.03 vs 0.14 ± 0.02) (P < 0.05). These results showed that ORY increased the mRNA expression of the transcripts associated with antioxidant enzymes and enhanced the developmental potential of heat-shocked bovine oocytes and warranted further studies to explore this antioxidant’s influence on improving dairy cattle’s reproductive efficiency during heat stress.

Putting the work of the poet Nathaniel Mackey into correspondence with that of the singer, composer, performance and video artist M. Lamar offers a unique perspective on the complex relationship between automation and possession. Mackey’s Andoumboulou and Mu move in and through M. Lamar so that possession and automation are destabilized and replaced by molecular distintegrations of plantation worlds and the sonic apertures of a Black Afrofuturist Android.

In 2019 British choreographer Seke Chimutengwende began research on a new project exploring horror, haunted houses, and the hauntings of colonial history. It begins in darkness (2022) emerged in collaboration with the dancers who perform each iteration. Working through the figure of the haunted stately home, It begins in darkness excavates—and exorcises—the horror of slavery’s histories through dance.

We show that on a $\sigma $-finite measure-preserving system $X = (X,\nu , T)$, the non-conventional ergodic averages

$$ \begin{align*} \mathbb{E}_{n \in [N]} \Lambda(n) f(T^n x) g(T^{P(n)} x) \end{align*} $$

$f \in L^{p_1}(X)$

$g \in L^{p_2}(X)$

$1/p_1 + 1/p_2 \leq 1$

$2$

$\Lambda $

$1$

$\mu $

Independent Christian Churches were an important aspect of African anticolonial activism, but the political afterlives of these movements in the immediate postcolonial period have been broadly overlooked. This article studies the African Independent Pentecostal Church, focusing on its entanglement with the politics of reconciliation and state-building in a decolonising Kenya. During the 1950s Mau Mau uprising, the church lost its entire portfolio of land, churches, and schools. The article explores how church adherents sought to re-establish themselves on these holdings. These contests reveal that churches were political agents engaged in debates about the boundaries of postcolonial political community and the nature of post-conflict reconciliation. Churches’ roles as landowners and education providers meant denominational rivalries masked political struggles over justice for past violations. Embedded in intra-ethnic conflicts, churches negotiated with elites seeking to establish ethnic constituencies. Through this conflict and compromise, the brokered nature of the postcolonial nation-building project is revealed.

Bodies in possession and in revolt are often framed as being “caught” by some other entity—a spirit, a force, or a memory. Cases of rebellion involve a loss of intentionality of movement, unlike a subject who wills and decides. What is the political significance of the illegibility of such movements, before they are consigned to taxonomies and diagnoses that render them pathological, criminal, or demonic? What thinking about dance might this permit?

Simultaneous localization and mapping technology is the basis for multi-robot systems to complete navigation, path planning, and autonomous exploration in complex, dynamic, and Global Positioning System (GPS)-denied environments. This paper reviews the current status and progress of multi-robot simultaneous localization and mapping (SLAM) technology based on LiDAR. First, this paper studies the basic principles of LiDAR SLAM. It analyzes the system model construction of LiDAR SLAM, including the mobile robot coordinate system model, kinematic model, sensor model, map presentation, LiDAR SLAM framework, and classic algorithms. Then, this paper discusses the basic framework of collaborative SLAM, analyzes the key issues such as data association, loop closure detection, and global graph optimization in collaborative SLAM, and conducts a detailed literature review on the solutions to key problems in sub-fields of multi-robot SLAM such as frontier detection, task allocation, map fusion, and compares the advantages and disadvantages of various algorithms. Finally, this paper outlines the challenges and future research directions of multi-robot LiDAR SLAM.

Ostracods from the late Mississippian–early Pennsylvanian (late Serpukhovian–Bashkirian) from the Calingasta–Uspallata Basin, Precordillera Argentina, are studied for the first time. The analyzed successions (Hoyada Verde, El Paso, Leoncito, and Yalguaraz formations) document the most widespread glacial event in southwestern Gondwana during the Late Paleozoic Ice Age. One new species, Aechmina cuyanensis new species, is defined, and seven species are described, two of which are new records for South America. The distribution of Carboniferous ostracods in the Argentine basins (Calingasta–Uspallata, Río Blanco, and Tepuel–Genoa) is discussed, highlighting the interesting record of this fauna in levels between or below diamictites and its absence in the mudstone interval with no evidence of glaciation. The association is characterized by ornamented palaeocopids, one binodicopid, and some metacopid species corresponding to the Assemblage III of the Eifelian Mega-Assemblage, indicating a slightly hypoxic and very calm environment between the fair-weather wave base and the storm wave base.

UUID: https://zoobank.org/68fda8dc-be98-4a03-b369-a696b7d7ad99

The present study examines the influence of non-economic factors on women’s labour market participation in low-income neighbourhoods of urban areas in India. For this purpose, we conducted a survey in two slum areas of Kolkata city in West Bengal – one, located in a residential neighbourhood, and another, situated in the dock area of the city and surrounded by factories. Our survey of 384 ever-married working-age women makes three noteworthy observations. First, the location of slums crucially affects the type of paid work that is available and accessible to women. Secondly, although women’s entry into the labour market maybe crisis-driven, the women workers develop an intrinsic valuation of paid work as their right, and as a means of livelihood in the process. Finally, social and community norms explain both the non-participation and the temporary withdrawal of women from the labour force. Thus, the inability and/or the unwillingness of slum women to participate in the labour market primarily stem from the strict adherence to patriarchal norms in general, and community norms in particular, either imposed on them directly by their spouses or indirectly by the community they reside in. Therefore, our analysis highlights the need for tailor-made policies that meet locality-specific needs.