Search

A letter to the editor is presented in response to the article on vegetation change published in the previous issue.

Abstract Background In a cross sectional study of 88 indoor and outdoor English pig farms, the prevalence of foot and limb lesions in 2843 preweaning piglets aged 1–4 weeks from 304 litters was recorded. The environmental risks for the prevalence of lesions and population attributable fractions were calculated. The risks for lesions in piglets were compared with those for limb and body lesions in their mothers. A small number of piglets with each type of lesion were examined post mortem to elucidate the pathology of the clinical lesions observed. Results The prevalence of sole bruising, sole erosion, skin abrasion and swollen joints or claws in 2843 piglets was 49.4% (1404), 15.5% (441), 43.6% (1240) and 4.7% (143) respectively. The prevalence of all foot and limb lesions was higher in indoor housed piglets than in outdoor housed piglets. The prevalence of sole bruising (OR 0.3) and skin abrasion (OR 0.6) decreased with each week of age from 1–4 weeks, but there was no significant association between piglet age and the prevalence of sole erosion or swollen joints and claws. There was an increased prevalence of sole bruising (OR 3.0) and swollen joints or claws (OR 3.0) and a decreased prevalence of skin abrasion (OR 0.3, piglets ≤ 1-week old), in piglets housed on slatted floors, compared with those on solid concrete floors with bedding. There was an increased risk of sole erosion associated with piglets housed on partly slatted floors with no bedding (OR 2.4) and partly slatted floors with small amounts of bedding (OR 2.9) compared with piglets housed on solid concrete floors with bedding in all areas of the pen. Post mortem examination of feet with lesions indicated that internal pathological changes were frequently more severe than the degree of external damage suggested. Conclusion Piglets housed outdoors had a very low prevalence of foot and limb injuries. Indoors, no one floor type was ideal to minimise all piglet foot and limb injuries and the flooring requirements of sows differed from those of piglets.

Abstract Background Lesions on sows' limbs and bodies are an abnormality that might impact on their welfare. The prevalence of and risks for limb and body lesions on lactating sows on commercial English pig farms were investigated using direct observation of the sows and their housing. Results The prevalence of lesions on the limbs and body were 93% (260/279) and 20% (57/288) respectively. The prevalence of limb and body lesions was significantly lower in outdoor-housed sows compared with indoor-housed sows. Indoor-housed sows had an increased risk of wounds (OR 6.8), calluses (OR 8.8) and capped hock (OR 3.8) on their limbs when housed on fully slatted floors compared with solid concrete floors. In addition, there was an increased risk of bursitis (OR 2.7), capped hock (OR 2.3) and shoulder lesions (OR 4.8) in sows that were unwilling to rise to their feet. There was a decreased risk of shoulder lesions (OR 0.3) and lesions elsewhere on the body (OR 0.2) in sows with more than 20 cm between their tail and the back of the crate compared with sows with less than 10 cm. Conclusion The sample of outdoor housed sows in this study had the lowest prevalence of limb and body lesions. In lactating sows housed indoors there was a general trend for an increased risk of limb and body lesions in sows housed on slatted floors compared with those housed on solid concrete floors with bedding. Sows that were less responsive to human presence and sows that had the least space to move within their crates had an additional increased risk of lesions.

Microcrystal electron diffraction (MicroED) has emerged as a powerful technique for unraveling molecular structures from microcrystals too small for X-ray diffraction. However, a significant hurdle arises with plate-like crystals that consistently orient themselves flat on the electron microscopy grid. If the normal of the plate correlates with the axes of the crystal lattice, the crystal orientations accessible for measurement are restricted because the crystal cannot be arbitrarily rotated. This limits the information that can be acquired, resulting in a missing cone of information. We recently introduced a novel crystallization strategy called suspended drop crystallization and proposed that crystals in a suspended drop could effectively address the challenge of preferred crystal orientation. Here we demonstrate the success of the suspended drop approach in eliminating the missing cone in two samples that crystallize as thin plates: bovine liver catalase and the SARS‑CoV‑2 main protease (Mpro). This innovative solution proves indispensable for crystals exhibiting systematic preferred orientations, unlocking new possibilities for structure determination by MicroED., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2024 The Authors.)

In this work, a novel crystal growth method termed suspended drop crystallization has been developed. Unlike traditional methods, this technique involves mixing protein and precipitant directly on an electron microscopy grid without any additional support layers. The grid is then suspended within a crystallization chamber designed in-house, allowing for vapor diffusion to occur from both sides of the drop. A UV-transparent window above and below the grid enables the monitoring of crystal growth via light, UV or fluorescence microscopy. Once crystals have formed, the grid can be removed and utilized for X-ray crystallography or microcrystal electron diffraction (MicroED) directly without having to manipulate the crystals. To demonstrate the efficacy of this method, crystals of the enzyme proteinase K were grown and its structure was determined by MicroED following focused ion beam/scanning electron microscopy milling to render the sample thin enough for cryoEM. Suspended drop crystallization overcomes many of the challenges associated with sample preparation, providing an alternative workflow for crystals embedded in viscous media, sensitive to mechanical stress and/or subject to preferred orientation on electron microscopy grids., (open access.)

Visualization researchers and visualization professionals seek appropriate abstractions of visualization requirements that permit considering visualization solutions independently from specific problems. Abstractions can help us design, analyze, organize, and evaluate the things we create. The literature has many task structures (taxonomies, typologies, etc.), design spaces, and related "frameworks" that provide abstractions of the problems a visualization is meant to address. In this Visualization Viewpoints article, we introduce a different one, a problem space that complements existing frameworks by focusing on the needs that a visualization is meant to solve. We believe it provides a valuable conceptual tool for designing and discussing visualizations.