EnderScope: a low-cost 3D printer-based scanning microscope for microplastic detection.

Low-cost and scalable technologies that allow people to measure microplastics in their local environment could facilitate a greater understanding of the global problem of marine microplastic pollution. A typical way to measure marine microplastic pollution involves imaging filtered seawater samples stained with a fluorescent dye to aid in the detection of microplastics. Although traditional fluorescence microscopy allows these particles to be manually counted and detected, this is a resource- and labour-intensive task. Here, we describe a novel, low-cost microscope for automated scanning and detection of microplastics in filtered seawater samples-the EnderScope. This microscope is based on the mechanics of a low-cost 3D printer (Creality Ender 3). The hotend of the printer is replaced with an optics module, allowing for the reliable and calibrated motion system of the 3D printer to be used for automated scanning over a large area (>20 × 20 cm). The EnderScope is capable of both reflected light and fluorescence imaging. In both configurations, we aimed to make the design as simple and cost-effective as possible, for example, by using low-cost LEDs for illumination and lighting gels as emission filters. We believe this tool is a cost-effective solution for microplastic measurement. This article is part of the Theo Murphy meeting issue 'Open, reproducible hardware for microscopy'.

Prevalence of intramammary antibiotic usage in dairy farming.

This research communication describes the lactating intramammary (IMM) antibiotic formulation most used by Irish dairy farmers at farm level through interviewing 202 dairy farmers. The IMM antibiotic usage data is not easily available to the researcher and farming community. This study determined that three commercial formulations (Synulox ™, Tetra Delta™ and Terrexine) made up 81% of the products used at farm level. The formulation Synulox™ was the most used at 34% first preference and 32% second preference and contains amoxicillin/clavulanic, a standard broad spectrum antibiotic, for which mastitis pathogen resistance remains low. The aminoglycosides were used in four of the IMM formulations analysed, including Tetra Delta™ and Terrexine. Of the 12 antibiotics identified in the IMM formulations studied, three including cefalexin, benzylpenicillin and penethamate are classified as highly important antibiotics (HIA) by the World Health Organisation (WHO) whilst the other 8 (dihydrostreptomycin, streptomycin, neomycin, framycetin, kanamycin, amoxicillin/clavulanic acid, and cefquinome), are considered critically important (CIA) for use in human health. This study has generated knowledge of the preferences of lactating IMM formulations used at farm level.

Association of Total Zinc Intake with Myopia in U.S. Children and Adolescents.

SIGNIFICANCE: This present study advances our knowledge on the role of lifestyle factors in myopia (short-sightedness), specifically dietary factors. It has been suggested in previous studies that lower zinc status is associated with myopia; however, this article shows no relationship between dietary zinc intake and myopia in U.S. adolescents. PURPOSE: It has been suggested that low zinc levels may contribute to the development of myopia. The aim of the present study is to examine, for the first time in a Western population, the association of total dietary and supplement zinc intake with myopia. METHODS: A total of 1095 children/adolescents aged 12 to 19 years who participated in the U.S. National Health and Nutrition Examination Survey from 2007 to 2008 were enrolled in this study. Multivariate logistic regression analysis was performed to examine the relationship between total zinc intake and myopia after adjustment for potential confounders. In addition, the association between total zinc intake and spherical equivalent refractive error was examined in the myopia group through multiple linear regression. RESULTS: Among study participants, 30% were found to be myopic (≤-1.00 D). Although median total daily zinc intake was lower among myopes (10.8 [10.2] mg/d) than among nonmyopes (11.1 [10.8] mg/d), the difference was not statistically significant (P = .11). In multiple logistic regression analyses, zinc and copper intakes were not significantly associated with myopia after adjustment for age, sex, body mass index, ethnicity, family income, recreational activity, copper intake, and daily energy intake (in kilocalories per day). In multiple linear regression, spherical equivalent refractive error was not associated with total zinc intake in the myopic group after adjustment for confounding factors (P = .13). CONCLUSIONS: In contrast to previous Asian studies, total zinc intake is not associated with the presence of myopia in U.S. adolescents/children.

Characterization of geometric variance in the epithelial nerve net of the ctenophore Pleurobrachia pileus.

Neuroscience lacks a diverse repertoire of model organisms, resulting in an incomplete understanding of the general principles of neural function. Ctenophores display many neurobiological and experimental features which make them a promising candidate to fill this gap. They possess a nerve net distributed across their body surface in the epithelial layer. There is a long-held assumption that nerve nets are "simple" and lack distinct organizational principles. We want to challenge this assumption and determine how stereotyped the structure of this network is. We estimated body surface area in Pleurobrachia pileus using custom optical projection tomography and light sheet morphometry imaging systems. Using an antibody against tyrosinated α-tubulin, we visualized the nerve net in situ and quantified the geometric properties using an automated segmentation approach. We characterized organizational rules of the epithelial nerve net in animals of different sizes and at different regions of the body. We found that specific morphological features within the nerve net are largely unchanged during growth. These properties must be essential to the functionality of the nervous system and therefore are maintained during a change in body size. We have also established the principles of organization of the network and showed that some of the geometric properties are variable across different parts of the body. This suggests that there may be different functions occurring in regions with different structural characteristics. This is the most comprehensive structural description of a ctenophore nerve net to date and demonstrates the amenability of P. pileus for whole organism network analysis.

The relationship between serum zinc levels and myopia.

CLINICAL SIGNIFICANCE: Nutritional status influences growth and development, including that of the eye. However, little attention has been given to possible dietary influences in myopia. This study demonstrates that serum zinc has no relationship with myopia development. BACKGROUND: Myopia is inherently associated with eye growth and thereby possibly amenable to nutritional influence. A number of Asian studies have reported lower levels of serum zinc in myopic children. This study was designed to assess the relationship between serum zinc and myopia in the Korean population - using a subsample of participants from nationally representative data. METHODS: Data from the fifth Korea National Health and Nutrition Examination Survey (KNHANES) 2010 were used to explore zinc status in relation to refraction. A total of 304 participants were analysed, ranging in age from 12 to 19-years. Serum zinc levels were measured using inductively coupled plasma mass spectrometry, while refractive error was determined by non-cycloplegic autorefraction. Multivariate analysis was used to examine the association. RESULTS: A significant majority of participants (n = 255; 84 per cent) were myopic. There was no significant difference in serum zinc levels between myopic and non-myopic children (p = 0.81). In multivariate logistic regression, serum zinc was not significantly associated with myopia after adjustment for age, gender, residence, body mass index, family income and recreational activity. Similarly, no relationship was observed between spherical equivalent refraction and serum zinc within the myopic group (p = 0.46). CONCLUSION: In a subset of 12-19-year-old participants from the population-representative KNHANES study, no association was found between serum zinc and myopia. However, the lack of a sensitive biomarker for zinc status remains a major limitation in this, and all current studies.

The incubot: A 3D printer-based microscope for long-term live cell imaging within a tissue culture incubator.

Commercial live cell imaging systems represent a large financial burden to research groups, while current open source incubator microscopy systems lack adaptability and are sometimes inadequate for complex imaging experimentation. We present here a low-cost microscope designed for inclusion within a conventional tissue culture incubator. The build is constructed using an entry level 3D printer as the basis for the motion control system, with Raspberry Pi imaging and software integration, allowing for reflected, oblique, and fluorescence imaging of live cell monolayers. The open source nature of the design is aimed to facilitate adaptation by both the community at large and by individual researchers/groups. The development of an adaptable and easy-to-use graphic user interface (GUI) allows for the scientist to be at the core of experimental design through simple modifications of the base GUI code, or generation of an entirely purpose-built script. This adaptability will allow scientists to adapt this equipment for their experimental needs, as opposed to designing experiments to fit their current equipment. The build can be constructed for a cost of roughly €1000 and thus serves as a low-cost and adaptable addition to the open source microscopy community.

Needs and Experiences of Children and Adolescents with Pediatric Multiple Sclerosis and Their Caregivers: A Systematic Review.

In the present study we conduct a systematic review to evaluate the needs and experience of people with pediatric multiple sclerosis (MS) and their caregivers. The literature search was conducted across 10 academic databases, adhering to PRISMA-P guidelines. Quality appraisal was conducted using the mixed method appraisal test for individual studies, and GRADE-CERQual to establish overall confidence of findings. Results were analyzed using a process of narrative synthesis. We identified 26 studies which included 2253 children/adolescents with MS (CAMS) and 1608 caregivers. MS was reported to negatively impact experiences for CAMS in domains such as of school performance, social relationships, mental health, and overall physical functioning. Specifically, fatigue and social support were reported as the most important barriers and facilitators for CAMS, respectively. In terms of caregiver experience, negative impacts were reported on social functioning, mental health, and quality of life. Additionally, lack of awareness concerning MS was one of the biggest challenges reported. Caregivers expressed needs for psychological and social support. This study provides the first evidence regarding the needs and experiences of CAMS and their caregivers. Findings can be used to address policy gaps for supporting families affected by pediatric MS.

The Flexiscope: a low cost, flexible, convertible and modular microscope with automated scanning and micromanipulation.

With technologies rapidly evolving, many research institutions are now opting to invest in costly, high-quality, specialized microscopes which are shared by many researchers. As a consequence, the user may not have the ability to adapt a microscope to their specific needs and limitations in experimental design are introduced. A flexible work-horse microscopy system is a valuable tool in any laboratory to meet the diverse needs of a research team and promote innovation in experimental design. We have developed the Flexiscope; a multi-functional, adaptable, efficient and high-performance microscopy/electrophysiology system for everyday applications in a neurobiology laboratory. The core optical components are relatively constant in the three configurations described here: an upright configuration, an inverted configuration and an upright/electrophysiology configuration. We have provided a comprehensive description of the Flexiscope. We show that this method is capable of oblique infrared illumination imaging, multi-channel fluorescent imaging and automated three-dimensional scanning of larger specimens. Image quality is conserved across the three configurations of the microscope, and conversion between configurations is possible quickly and easily, while the motion control system can be repurposed to allow sub-micrometre computer-controlled micromanipulation. The Flexiscope provides similar performance and usability to commercially available systems. However, as it can be easily reconfigured for multiple roles, it can remove the need to purchase multiple microscopes, giving significant cost savings. The modular reconfigurable nature allows the user to customize the system to their specific needs and adapt/upgrade the system as challenges arise, without requiring specialized technical skills.

Serial femtosecond crystallography on in vivo-grown crystals drives elucidation of mosquitocidal Cyt1Aa bioactivation cascade.

Cyt1Aa is the one of four crystalline protoxins produced by mosquitocidal bacterium Bacillus thuringiensis israelensis (Bti) that has been shown to delay the evolution of insect resistance in the field. Limiting our understanding of Bti efficacy and the path to improved toxicity and spectrum has been ignorance of how Cyt1Aa crystallizes in vivo and of its mechanism of toxicity. Here, we use serial femtosecond crystallography to determine the Cyt1Aa protoxin structure from sub-micron-sized crystals produced in Bti. Structures determined under various pH/redox conditions illuminate the role played by previously uncharacterized disulfide-bridge and domain-swapped interfaces from crystal formation in Bti to dissolution in the larval mosquito midgut. Biochemical, toxicological and biophysical methods enable the deconvolution of key steps in the Cyt1Aa bioactivation cascade. We additionally show that the size, shape, production yield, pH sensitivity and toxicity of Cyt1Aa crystals grown in Bti can be controlled by single atom substitution.