Validity evidence for an instrument for cognitive load for virtual didactic sessions

Background: COVID necessitated the shift to virtual resident instruction. The challenge of learning via virtual modalities has the potential to increase cognitive load. It is important for educators to reduce cognitive load to optimize learning, yet there are few available tools to measure cognitive load. The objective of this study is to identify and provide validity evidence following Messicks’ framework for an instrument to evaluate cognitive load in virtual emergency medicine didactic sessions.
Methods: This study followed Messicks’ framework for validity including content, response process, internal structure, and relationship to other variables. Content validity evidence included: (1) engagement of reference librarian and literature review of existing instruments; (2) engagement of experts in cognitive load, and relevant stakeholders to review the literature and choose an instrument appropriate to measure cognitive load in EM didactic presentations. Response process validity was gathered using the format and anchors of instruments with previous validity evidence and piloting amongst the author group. A lecture was provided by one faculty to four residency programs via ZoomTM. Afterwards, residents completed the cognitive load instrument. Descriptive statistics were collected; Cronbach’s alpha assessed internal consistency of the instrument; and correlation for relationship to other variables (quality of lecture).
Results: The 10-item Leppink Cognitive Load instrument was selected with attention to content and response process validity evidence. Internal structure of the instrument was good (Cronbach’s alpha = 0.80). Subscales performed well-intrinsic load (α = 0.96, excellent), extrinsic load (α = 0.89, good), and germane load (α = 0.97, excellent). Five of the items were correlated with overall quality of lecture (< 0.05).
Conclusions: The 10-item Cognitive Load instrument demonstrated good validity evidence to measure cognitive load and the subdomains of intrinsic, extraneous, and germane load. This instrument can be https://biodas.org/ used to provide feedback to presenters to improve the cognitive load of their presentations.

Assessment of the influence of gluten quality on highland barley dough sheet quality by different instruments

  • This study was to compare the results of texture analyzer with those of farinograph and extensograph and determine whether texture analyzer could be used to evaluate the processing quality of highland barley flour (HBF) dough sheet. The farinograph and extensograph tests were used to determine the reconstituted flour properties, a texture analyzer was applied to measure the tensile strength of HBF dough sheet, and the content of glutenin macropolymer (GMP), free sulfhydryl (-SH) and secondary structure of protein and microstructure in HBF dough sheet were investigated. Furthermore, correlations between these parameters were determined by regression analysis and Pearson correlation coefficient.
  • It was suggested that the reconstituted flours with a higher gluten index showed a higher farinograph quality number (FQN) and greater maximum resistance to extension (Rm ). HBF dough sheets with higher gluten index possessed higher GMP and lower free -SH contents, a more ordered secondary structure of protein, resulting in a more compact gluten network and a stronger tensile strength (TS).
  • The regression and correlation analysis showed that TS was positively correlated with FQN and Rm . In addition, it was significantly correlated with the content of GMP, -SH, secondary structure of protein and gluten network. It was concluded that texture analyzer could be an alternative approach to evaluate the processing quality of HBF dough sheet. Moreover, the gluten index of flours could be used to predict the processing quality of HBF dough sheet. This article is protected by copyright. All rights reserved.

Development of an Instrument to Assess the Stability of Cementless Femoral Implants Using Vibration Analysis During Total Hip Arthroplasty

Objective: The level of primary implant fixation in cementless total hip arthroplasty is a key factor for the longevity of the implant. Vibration-based methods show promise for providing quantitative information to help surgeons monitor implant fixation intraoperatively. A thorough understanding of what is driving these changes in vibrational behavior is important for further development and improvement of these methods. Additionally, an instrument must be designed to enable surgeons to leverage these methods. This study addresses both of these issues.
Method: An augmented system approach was used to develop an instrument that improves the sensitivity of the vibrational method and enables the implementation of the necessary excitation and measurement equipment. The augmented system approach took into account the dynamics of the existing bone-implant system and its interaction with the added instrument.
Results: Two instrument designs are proposed, accompanied by a convergence-based method to determine the insertion endpoint. The modal strain energy density distribution was shown to affect the vibrational sensitivity to contact changes in certain areas.
Conclusion: The augmented system approach led to an instrument design that improved the sensitivity to changes in the proximal region of the combined bone-implant-instrument system. This fact was confirmed both in silico and in vitro. Clinical Impact: The presented method and instruments address practical intraoperative challenges and provide perspective to objectively support the surgeon’s decision-making process, which will ensure optimal patient treatment.

Validation of the PAM-13 instrument in the Hungarian general population 40 years old and above

Background: Patient activation comprises the skills, knowledge and motivation necessary for patients’ effective contribution to their care. We adapted and validated the 13-item Patient Activation Measure (PAM-13) in the ≥ 40 years old Hungarian general population.
Methods: A cross-sectional web survey was conducted among 900 respondents selected from an online panel via quota sampling. After 10 days, the survey was repeated on 100 respondents. The distribution, internal consistency, test-retest reliability, factor structure, convergent, discriminant and known-groups validity of PAM-13 were assessed according to the COSMIN guidelines.
Results: The sample comprised 779 respondents. Mean (± SD) age was 60.4 ± 10.6 years, 54% were female and 67% had chronic illness. Mean (± SD) PAM-13 score was 60.6 ± 10.0. We found good internal consistency (Cronbach alpha: 0.77), moderate test-retest reliability (ICC: 0.62; n = 75), a single-factor structure and good content validity: PAM-13 showed moderate correlation with the eHealth Literacy Scale (r = 0.40), and no correlation with age (r = 0.02), education (r = 0.04) or income (ρ = 0.04). Higher PAM-13 scores were associated with fewer lifestyle risks (p < 0.001), more frequent health information seeking (p < 0.001), participation in patient education (p = 0.018) and various online health-related behaviours. When controlling for health literacy, sociodemographic factors and health status, the association of higher PAM-13 scores with overall fewer lifestyle risks, normal body mass index, physical activity and adequate diet remained significant. Similar properties were observed in the subgroup of participants with chronic morbidity, but not in the age group 65+.
Conclusion: PAM-13 demonstrated good validity in the general population. Its properties in clinical populations and the elderly as well as responsiveness to interventions warrant further research.
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Evaluation of a Wearable Non-Invasive Thermometer for Monitoring Ear Canal Temperature during Physically Demanding (Outdoor) Work

Aimed at preventing heat strain, health problems, and absenteeism among workers with physically demanding occupations, a continuous, accurate, non-invasive measuring system may help such workers monitor their body (core) temperature. The aim of this study is to evaluate the accuracy and explore the usability of the wearable non-invasive Cosinuss° °Temp thermometer. Ear canal temperature was monitored in 49 workers in real-life working conditions. After individual correction, the results of the laboratory and field study revealed high correlations compared to ear canal infrared thermometry for hospital use. After performance of the real-life working tasks, this correlation was found to be moderate.
It was also observed that the ambient environmental outdoor conditions and personal protective clothing influenced the accuracy and resulted in unrealistic ear canal temperature outliers. It was found that the Cosinuss° °Temp thermometer did not result in significant interference during work. Therefore, it was concluded that, without a correction factor, the Cosinuss° °Temp thermometer is inaccurate. Nevertheless, with a correction factor, the reliability of this wearable ear canal thermometer was confirmed at rest, but not in https://biodas.org/ outdoor working conditions or while wearing a helmet or hearing protection equipment.

Mobile Health-Based Thermometer for Monitoring Wound Healing After Endovascular Therapy in Patients With Chronic Foot Ulcer: Prospective Cohort StudY

Background: Foot temperature may increase after endovascular therapy, but the relationship between foot temperature and wound healing is unclear.
Objective: This study was performed to evaluate the feasibility of a mobile health (mHealth)-based thermometer for foot temperature monitoring in patients with chronic foot ulcer before and after endovascular therapy and to determine the association between temperature change and wound healing time.
Methods: This was a prospective cohort study. Patients who had a chronic foot ulcer (>3 months) and underwent endovascular therapy between June 2019 and December 2019 were included. The participants received standard medical care and endovascular therapy for revascularization. The mHealth-based thermometer, composed of 4 temperature-sensing chips, was put on the foot before and after endovascular therapy. Data from the chips were transferred to an associated mobile phone app via Bluetooth. Wound healing time was estimated using the Kaplan-Meier method, and the associations between baseline characteristics and clinical outcomes were evaluated using a Cox proportional hazard model.
Results: A total of 163 patients with chronic foot ulcer who underwent endovascular therapy were enrolled and followed up until wound healing was complete or for 180 days. The mean foot temperature before endovascular therapy was 30.6 (SD 2.8 °C). Foot temperature increased significantly (mean 32.1 °C, SD 2.8 °C; P=.01) after the procedure. Wound healing time was significantly different in the Kaplan-Meier curves of the patient group with temperature changes ≥2 °C and the group with temperature changes ≤2 °C (log-rank P<.001). A foot temperature increase ≥2 °C after endovascular therapy was associated with increased wound healing in univariate analysis (hazard ratio [HR] 1.78, 95% CI 1.24-2.76, P=.02), and the association remained significant in multivariate analysis (HR 1.69, 95% CI 1.21-2.67, P=.03).
Conclusions: The mHealth-based thermometer was feasible and useful for foot temperature monitoring, which may provide health care professionals with a new endpoint for endovascular therapy. Foot temperature increases ≥2 °C after endovascular therapy were associated with faster wound healing in patients with chronic foot ulcer. Further studies are needed, however, to confirm these findings.

Tympanic thermometers support fast and accurate temperature monitoring in acute and alternative care

This article explores body temperature and the physiological process of thermoregulation. Normal body temperature and body temperature changes are discussed, including comorbidities associated with body temperature and signs of hyperthermia and hypothermia, and the factors that affect intraoperative temperature regulation.
The evidence base behind thermometry is discussed and is applied to contemporary clinical conditions and symptoms, including: sepsis and suspected COVID-19. After discussing clinical considerations and regulations that encompass thermometry, three case studies present the use of the Genius 3 Tympanic Thermometer in clinical practice, with user feedback supporting its benefits, which include speed, accuracy and ease of use.

Mitochondria-Anchored Molecular Thermometer Quantitatively Monitoring Cellular Inflammations

Temperature in mitochondria can be a critical indicator of cell metabolism. Given the highly dynamic and inhomogeneous nature of mitochondria, it remains a big challenge to quantitatively monitor the local temperature changes during different cellular processes. To implement this task, we extend our strategy on mitochondria-anchored thermometers from “on-off” probe Mito-TEM to a ratiometric probe Mito-TEM 2.0 based on the Förster resonance energy transfer mechanism. Mito-TEM 2.0 exhibits not only a sensitive response to temperature through the ratiometric changes of dual emissions but also the specific immobilization in mitochondria via covalent bonds.
Both characters support accurate and reliable detection of local temperature for a long time, even in malfunctioning mitochondria. By applying Mito-TEM 2.0 in fluorescence ratiometric imaging of cells and zebrafishes, we make a breakthrough in the quantitative visualization of mitochondrial temperature rises in different inflammation states.

Non-invasive and wearable thermometer for continuous monitoring of core body temperature under various convective conditions

We describe the design of a thermometer that can be worn during everyday activities for monitoring core body temperature (CBT) at the skin surface. This sensor estimates the CBT by measuring the heat flux from the body core based on a thermal conductive model. The heat flux is usually affected by the ambient convective conditions (e.g. air conditioner or posture), which in turn affects the model’s accuracy. Thus, we analytically investigated heat conduction and designed a sensor interface that would be robust to convection changes. We performed an in vitro experiment and a preliminary in vivo experiment. The accuracy of CBT in an in vitro experiments was 0.1°C for convective values ranging from 0 to 1.2 m/s. The wearable thermometer has high potential as non-invasive CBT monitor.

Effect of monitoring the onset of calving by a calving alarm thermometer on the prevalence of dystocia, stillbirth, retained fetal membranes and clinical metritis in a Hungarian dairy farm

The objective of the present study was to assess the effectiveness of an intravaginal thermometer in the field prediction of the second stage of labor and to determine its impact on the health of dams and newborn calves. Holstein cows (n = 241) were randomly selected about 5 (mean ± SD: 4.7 ± 2.0) days before the expected date of calving and the thermometer was inserted into the vagina. Another 113 cattle served as controls. There was no false alarm during the experiment. The risk of dystocia (Score >1) was 1.9 times higher, the prevalence of stillbirth was 19.8 times higher, the risk of retained fetal membranes (RFM) was 2.8 times higher and the risk of clinical metritis was 10.5 times higher in the control group than in the experimental group.
The prevalence of stillbirth was 7 times higher in cows with dystocia compared to cows with eutocia. The presence of dystocia and stillbirth increased the risk of RFM 4 and 5 times, respectively. The occurrence of RFM increased the risk of development of clinical metritis with a 22 times higher odds. The results indicate that the use of calving alert systems not only facilitates controlling the time of parturition and providing prompt and appropriate calving assistance but also decreases the number of dystocia cases and improves reproductive efficiency, postpartum health of the dam and newborn calf survival.
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Scalable and Robust Bacterial Cellulose Carbon Aerogels as Reusable Absorbents for High-Efficiency Oil/Water Separation

Efficient selective separation of oils or organic pollutants from water is important for ecological, environmental conservation and sustainable development. Various absorption methods have emerged; the majority of them still suffer from defects including low removal efficiency, a complicated preparation process, and high cost. Herein, we present a highly porous and mechanical resilient bacterial cellulose (BC) carbon aerogel directly from BC hydrogel via facile directional freeze-drying and high-temperature carbonization. The resultant BC carbon aerogel showed excellent mechanical compressibility (maximal height compression ∼99.5%) and elastic recovery due to the porous structure. Taking advantages of the high thermal stability and superhydrophobicity, the BC carbon aerogel was directly used as a versatile adsorbent for oil/water separation.
The result demonstrated that the BC carbon aerogel showed super oil/water separation selectivity with the oil absorption capacity as high as 132-274 g g-1. More importantly, the BC carbon aerogel adsorbent can be reused by a simple absorption/combustion method and still keep high-efficiency oil absorption capacity and excellent superhydrophobicity after 20 absorption/combustion cycles, displaying recyclability and robust stability. In sum, the BC carbon aerogel introduced here is easy to fabricate, ecofriendly, highly scalable, low cost, mechanically robust, and reusable; https://biodas.org/ all of these features make it highly attractive for oil/water separation application.

A camphene-camphor-polymer composite material for the production of superhydrophobic absorbent microporous foams

In a recently published paper (doi.org/10.3390/molecules26113116) on self-propelled motion of objects on the water surface, we described a novel surface-active plastic material obtained by dissolution of camphor and polypropylene in camphene at 250 [Formula: see text]C. The material has wax-like mechanical properties, can be easily formed to any moldable shape, and allows for longer and more stable self-propelled motion if compared with pure camphor or pure camphene or of a camphene-camphor wax.
Here we use scanning electron microscopy to visualize and characterize the microporous structure of the solid polypropylene foam formed in the plastic for different polypropylene contents. The topology of foams remaining in the material after camphor and camphene molecules have been removed through evaporation or dissolution is similar to polypropylene foams obtained using thermally-induced phase separation. We show that the foams have a superhydrophobic surface but strongly absorb non-polar liquids, and suggest an array of potential scientific and industrial applications.

Development of pH-responsive absorbent pad based on polyvinyl alcohol/agarose/anthocyanins for meat packaging and freshness indication

Absorbent pads with antioxidant and pH-responsive color changing functions have been developed based on polyvinyl alcohol (PVA), agarose (AG), and purple sweet potato anthocyanins (PSPA), aiming for fresh keeping and freshness indication of fresh meat. The effects of PSPA content on the structure, physical properties, and colorimetric response towards pH changing of pads were evaluated. The results showed that PSPA interacted with PVA and AG and influenced the crystallinity, thermal stability and micro-morphology of pads.
The increase of the PSPA content from 3% to 12% improved the strength and DPPH radical scavenging activity of the pads, but reduced the swelling ratio. Significant color change of the pads was observed when pH increased from 3 to 10, and the pad containing 9% PSPA presented the most distinguishable color change with the change of pH. When applied as an absorbent pad for minced meat packaging, the pad indicated the real-time spoilage of the meat through obvious color change, and also extended the shelf life by at least 24 h. Therefore, the dual-functional pad shows great potential to be applied as a smart and active packaging for fresh meat, which would play an important role in ensuring food safety and improving food storage quality.

Occurrence and distribution of organic ultraviolet absorbents in sediments from small urban rivers, Tianjin, China: Implications for risk management

Organic ultraviolet absorbents (OUVAs) in the environment have been of increasing concern because of their potential hazards. However, the OUVAs in waters is far from being well studied and little is known about their occurrence in small urban rivers. This study investigated the concentrations and distribution of eleven OUVAs in the sediments from five small urban rivers of Tianjin, China, and found total concentrations in the range of 11.6-189 ng/g dry weight. Relative to other rivers and lakes, no high concentrations of sediment OUVAs were observed in the small rivers. Benzophenone, homosalate and octocrylene were the dominant OUVAs, representing medians of 13.3%, 12.4% and 12.3% of the total concentrations, respectively.
Our observed composition profiles of these chemicals were different from those found in most of other waters. The sediment OUVAs may originate more from industrial activities than the use of cosmetics and personal care products in this area. The risk to aquatic organisms from exposure to the sediment OUVAs in these small urban rivers was considered low, except for benzophenone. However, more researches are needed to investigate the pollution and associated risks of these chemicals in urban rivers due to the complexity of their toxicity to aquatic organisms.

Mixture Compound Fertilizer and Super Absorbent Polymer Application Significantly Promoted Growth and Increased Nutrient Levels in Pinus massoniana Seedlings and Soil in Seriously Eroded Degradation Region of Southern China

  • Pinus massoniana is the pioneer tree species in the red soil regions of southern China, however, the serious understory soil erosion and nutrient deficiency in that region are the main factors restricting the growth of P. massoniana. This field study examined the effects of compound fertilizer and super absorbent polymer (SAP) on the physiology, growth characteristics, biomass, soil nutrient, plant nutrient content, and nutrient uptake efficiency of 1-year-old P. massoniana seedlings for 2 years at Changting, Fujian in South China. One control (no fertilizer, CK) and fertilization treatments were established, namely, single compound fertilizer application (0.94, 1.89, and 3.56 g⋅plant-1) and mixture compound fertilizer and SAP application (0.94 + 1.01, 1.89 + 1.01, and 3.56 + 1.01 g⋅plant-1).
  • Fertilization significantly improved the physiological performance, root collar diameter growth, height growth, biomass, and nutrient uptake of the seedlings. Compared with other fertilization treatments, the mixture compound fertilizer and SAP application significantly improved the seedling photosynthesis, which meant that the SAP had a significant effect on promoting photosynthesis. Under the mixture compound fertilizer and SAP application, the whole biomass of the seedlings was higher than that of all other treatments. Fertilization significantly increased the nitrogen (N), phosphorus (P), and potassium (K) content in the soils, leaves, stems, and roots of the seedlings, respectively.
  • The P content was the main factor affecting growth characteristics and contributed to 58.03% of the total variation in seedling growth characteristics (P < 0.01). The N:P ratio of CK in the soils, leaves, and stems were higher than that of all the fertilization treatments, indicating that the severely eroded and degraded region had little P and required much of P. The principal component analysis indicated that the F2S (1.89 + 1.01 g) was the optimum fertilization amount and method in this experiment. These results provide a theoretical basis for the fertilization management of P. massoniana forests with severely eroded and degraded red soil regions.
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Superhydrophobic paper in the development of disposable labware and lab-on-paper devices

Traditionally in superhydrophobic surfaces history, the focus has frequently settled on the use of complex processing methodologies using nonbiodegradable and costly materials. In light of recent events on lab-on-paper emergence, there are now some efforts for the production of superhydrophobic paper but still with little development and confined to the fabrication of flat devices. This work gives a new look at the range of possible applications of bioinspired superhydrophobic paper-based substrates, obtained using a straightforward surface modification with poly(hydroxybutyrate). As an end-of-proof of the possibility to create lab-on-chip portable devices, the patterning of superhydrophobic paper with different wettable shapes is shown with low-cost approaches.
Furthermore, we suggest the use of superhydrophobic paper as an extremely low-cost material to design essential nonplanar lab apparatus, including reservoirs for liquid storage and manipulation, funnels, tips for pipettes, or accordion-shaped substrates for liquid transport or mixing. Such devices take the advantage of the self-cleaning and extremely water resistance properties of the surfaces https://biodas.org/ as well as the actions that may be done with paper such as cut, glue, write, fold, warp, or burn. The obtained substrates showed lower propensity to adsorb proteins than the original paper, kept superhydrophobic character upon ethylene oxide sterilization and are disposable, suggesting that the developing devices could be especially adequate for use in contact with biological and hazardous materials.

Contaminating levels of zinc found in commonly-used labware and buffers affect glycine receptor currents

Zinc is an allosteric modulator of glycine receptor function, enhancing the effects of glycine at nM to low μM concentrations, and inhibiting its effects at higher concentrations. Because of zinc’s high potency at the glycine receptor, there exists a possibility that effects attributed solely to exogenously-applied glycine in fact contain an undetected contribution of zinc acting as an allosteric modulator. We found that glycine solutions made up in standard buffers and using deionized distilled water produced effects that could be decreased by the zinc chelator tricine.
This phenomenon was observed in three different vials tested and persisted even if vials were extensively washed, suggesting the zinc was probably present in the buffer constituents. In addition, polystyrene, but not glass, pipets bore a contaminant that enhanced glycine receptor function and that could also be antagonized by tricine. Our findings suggest that without checking for this effect using a chelator such as tricine, one cannot assume that responses elicited by glycine applied alone are not necessarily also partially due to some level of allosteric modulation by zinc.

Labware additives identified to be selective monoamine oxidase-B inhibitors

Plastic labware is used in all processes of modern pharmaceutical research, including compound storage and biological assays. The use of these plastics has created vast increases in productivity and cost savings as experiments moved from glass test tubes and capillary pipettes to plastic microplates and multichannel liquid handlers. One consequence of the use of plastic labware, however, is the potential release of contaminants and their resultant effects on biological assays.
We report herein the identification of biologically active substances released from a commonly used plastic microplate. The active contaminants were identified by gas chromatography-mass spectroscopy as dodecan-1-ol, dodecyl 3-(3-dodecoxy-3-oxopropyl)sulfanylpropanoate, and dodecanoic acid, and they were found to be selective monoamine oxidase-B inhibitors.

Open Labware: 3-D printing your own lab equipment

The introduction of affordable, consumer-oriented 3-D printers is a milestone in the current “maker movement,” which has been heralded as the next industrial revolution. Combined with free and open sharing of detailed design blueprints and accessible development tools, rapid prototypes of complex products can now be assembled in one’s own garage–a game-changer reminiscent of the early days of personal computing. At the same time, 3-D printing has also allowed the scientific and engineering community to build the “little things” that help a lab get up and running much faster and easier than ever before.

3D Printing in the Laboratory: Maximize Time and Funds with Customized and Open-Source Labware

3D-Printed Labware for High-Throughput Immobilization of Enzymes

  1. In continuous flow biocatalysis, chemical transformations can occur under milder, greener, more scalable, and safer conditions than conventional organic synthesis. However, the method typically involves extensive screening to optimize each enzyme’s immobilization on its solid support material. The task of weighing solids for large numbers of experiments poses a bottleneck for screening enzyme immobilization conditions.
  2. For example, screening conditions often require multiple replicates exploring different support chemistries, buffer compositions, and temperatures. Thus, we report 3D-printed labware designed to measure and handle solids in multichannel format and expedite screening of enzyme immobilization conditions.
  3. To demonstrate the generality of these advances, alkaline phosphatase, glucose dehydrogenase, and laccase were screened for immobilization efficiency on seven resins. The results illustrate the requirements for optimization of each enzyme’s loading and resin choice for optimal catalytic performance. Here, 3D-printed labware can decrease the requirements for an experimentalist’s time by >95%.
  4. The approach to rapid optimization of enzyme immobilization is applicable to any enzyme and many solid support resins. Furthermore, the reported devices deliver precise and accurate aliquots of essentially any granular solid material.

Adsorption of bacteriophages on polypropylene labware affects the reproducibility of phage research

Hydrophobicity is one of the most critical factors governing the adsorption of molecules and objects, such as virions, on surfaces. Even moderate change of wetting angle of plastic surfaces causes a drastic decrease ranging from 2 to 5 logs of the viruses (e.g., T4 phage) in the suspension due to adsorption on polymer vials’ walls. The effect varies immensely in seemingly identical containers but purchased from different vendors. Comparison of glass, polyethylene, polypropylene, and polystyrene containers revealed a threshold in the wetting angle of around 95°: virions adsorb on the surface of more hydrophobic containers, while in more hydrophilic vials, phage suspensions are stable.
The polypropylene surface of the Eppendorf-type and Falcon-type can accommodate from around 108 PFU/ml to around 1010 PFU/ml from the suspension. The adsorption onto the container’s wall might result in complete scavenging of virions from the bulk. We developed two methods to overcome this issue. The addition of surfactant Tween20 and/or plasma treatment provides a remedy by modulating surface wettability and inhibiting virions’ adsorption. Plastic containers are essential consumables in the daily use of many bio-laboratories. Thus, this is important not only for phage-related research (e.g., the use of phage therapies as an alternative for antibiotics) but also for data comparison and reproducibility in the field of biochemistry and virology.
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Contaminating levels of zinc found in commonly-used labware and buffers affect glycine receptor currents

Zinc is an allosteric modulator of glycine receptor function, enhancing the effects of glycine at nM to low μM concentrations, and inhibiting its effects at higher concentrations. Because of zinc’s high potency at the glycine receptor, there exists a possibility that effects attributed solely to exogenously-applied glycine in fact contain an undetected contribution of zinc acting as an allosteric modulator. We found that glycine solutions made up in standard buffers and using deionized distilled water produced effects that could be decreased by the zinc chelator tricine.
This phenomenon was observed in three different vials tested and persisted even if vials were extensively washed, suggesting the zinc was probably present in the buffer constituents. In addition, polystyrene, but not glass, pipets bore a contaminant that enhanced glycine receptor function and that could also be antagonized by tricine. Our findings suggest that without checking for this effect using a chelator such as tricine, one cannot assume that responses elicited by glycine applied alone are not necessarily also partially due to some level of allosteric modulation by zinc.

Superhydrophobic paper in the development of disposable labware and lab-on-paper devices

Traditionally in superhydrophobic surfaces history, the focus has frequently settled on the use of complex processing methodologies using nonbiodegradable and costly materials. In light of recent events on lab-on-paper emergence, there are now some efforts for the production of superhydrophobic paper https://biodas.org/ but still with little development and confined to the fabrication of flat devices. This work gives a new look at the range of possible applications of bioinspired superhydrophobic paper-based substrates, obtained using a straightforward surface modification with poly(hydroxybutyrate). As an end-of-proof of the possibility to create lab-on-chip portable devices, the patterning of superhydrophobic paper with different wettable shapes is shown with low-cost approaches.
Furthermore, we suggest the use of superhydrophobic paper as an extremely low-cost material to design essential nonplanar lab apparatus, including reservoirs for liquid storage and manipulation, funnels, tips for pipettes, or accordion-shaped substrates for liquid transport or mixing. Such devices take the advantage of the self-cleaning and extremely water resistance properties of the surfaces as well as the actions that may be done with paper such as cut, glue, write, fold, warp, or burn. The obtained substrates showed lower propensity to adsorb proteins than the original paper, kept superhydrophobic character upon ethylene oxide sterilization and are disposable, suggesting that the developing devices could be especially adequate for use in contact with biological and hazardous materials.

3D Printing in the Laboratory: Maximize Time and Funds with Customized and Open-Source Labware

3D-Printed Labware for High-Throughput Immobilization of Enzymes

In continuous flow biocatalysis, chemical transformations can occur under milder, greener, more scalable, and safer conditions than conventional organic synthesis. However, the method typically involves extensive screening to optimize each enzyme’s immobilization on its solid support material. The task of weighing solids for large numbers of experiments poses a bottleneck for screening enzyme immobilization conditions. For example, screening conditions often require multiple replicates exploring different support chemistries, buffer compositions, and temperatures.
Thus, we report 3D-printed labware designed to measure and handle solids in multichannel format and expedite screening of enzyme immobilization conditions. To demonstrate the generality of these advances, alkaline phosphatase, glucose dehydrogenase, and laccase were screened for immobilization efficiency on seven resins. The results illustrate the requirements for optimization of each enzyme’s loading and resin choice for optimal catalytic performance. Here, 3D-printed labware can decrease the requirements for an experimentalist’s time by >95%. The approach to rapid optimization of enzyme immobilization is applicable to any enzyme and many solid support resins. Furthermore, the reported devices deliver precise and accurate aliquots of essentially any granular solid material.

Additive manufactured customizable labware for biotechnological purposes

An Economical, Portable Manual Cryogenic Plunge Freezer for the Preparation of Vitrified Biological Samples for Cryogenic Electron Microscopy.

Visualizing biological structures and cellular processes in their native state is a major goal of many scientific laboratories. In the past 20 years, the technique of preserving samples by vitrification has greatly expanded, specifically for use in cryogenic electron microscopy (cryo-EM). Here, we report on improvements in the design and use of a portable manual cryogenic plunge freezer that is intended for use in laboratories that are not equipped for the cryopreservation of samples.

The construction of the instrument is economical, can be produced by a local machine shop without specialized equipment, and lowers the entry barriers for newcomers with a reliable alternative to costly commercial equipment. The improved design allows for successful freezing of isolated proteins for single particle analysis https://biodas.org/ as well as bacterial cells for cryo-electron tomography. With this instrument, groups will be able to prepare vitreous samples whenever and wherever necessary, which can then be imaged at local or national cryo-EM facilities.

Successful short-term cryopreservation of volume-reduced cord blood units in a cryogenic mechanical freezer: effects on cell recovery, viability, and clonogenic potential

BACKGROUND
Cord blood (CB) units are stored from weeks to years in liquid- or vapor-phase nitrogen until they are used for transplantation. We examined the effects of cryostorage in a mechanical freezer at -150°C on critical quality control variables of CB collections to investigate the possible use of mechanical freezers at -150°C as an alternative to storage in liquid- (or vapor-) phase nitrogen.
METHODS
A total of 105 CB units were thawed and washed at different time intervals (6, 12, 24, and 36 months). For every thawed CB unit, samples were removed and cell enumeration (total nucleated cells [TNCs], mononuclear cells [MNCs], CD34+, CD133+) was performed. In addition, viability was obtained with the use of flow cytometry, and recoveries were calculated. Also, total absolute colony-forming unit counts were performed and progenitor cell recoveries were studied by clonogenic assays.
RESULTS
Significant differences (p < 0.05) were observed in certain variables (TNCs, MNC numbers, viability) when they were examined in relation with time intervals, while others (CD34+, CD133+) were relatively insensitive (p = NS) to the duration of time interval the CB units were kept in cryostorage condition.
CONCLUSIONS
The data presented suggest that cryopreservation of CB units in a mechanical freezer at -150°C may represent an alternative cryostorage condition for CB cryopreservation.

Realignment-free cryogenic macroscopic optical cavity coupled to an optical fiber

We present a cryogenic setup where an optical Fabry-Perot resonator is coupled to a single-mode optical fiber with coupling efficiency above 90% at mK temperatures without realignment during cooling down. The setup is prealigned at room temperature to compensate for the thermal contraction and change of the refractive index of the optical components during cooling down.

The high coupling efficiency is achieved by keeping the setup rotation-symmetric around the optical axis. The majority of the setup components are made of Invar (FeNi36), which minimizes the thermal contraction. High coupling efficiency is essential in quantum optomechanical experiments.

Extraordinary approach to further boost plasmonic NIR-SERS by cryogenic temperature-suppressed non-radiative recombination

We report an effective strategy to promote the near-infrared surface-enhanced Raman scattering spectroscopy (NIR-SERS) activity by boosting the photon-induced charge transfer (PICT) efficiency at cryogenic temperature. Based on as-prepared Au/Ag nano-urchins (NUs) with abundant surface defects, the extremely low temperature (77 K) can significantly weaken the metallic lattice vibration and reduce the recombination of thermal phonons and photoexcited electrons, then accelerate the migration of energetic electrons.
It enables the NIR-SERS detection limit of dye molecules to be achieved at 10-17 M, which is nearly three orders of magnitude better than that at room temperature. The present work provides a new, to the best of our knowledge, approach for ultra-trace NIR-SERS bioanalysis.

Ultra-stretchable and fast self-healing ionic hydrogel in cryogenic environments for artificial nerve fiber

Self-healing materials behave irreplaceable advantages in biomimetic intelligent robots (BIR) for avoiding or reducing safety hazards and economic losses from accidental damage during service. However, the self-healing ability is unreservedly lost and even becomes rigid, fragile in the cryogenic environment where BIR is precisely needed. Here, we report a versatile ionic hydrogel with fast self-healing ability, ultra-stretchability, and stable conductivity, even at -80℃.
The hydrogel is systematically optimized to improve hydrogen-bonded network nanostructure, coordinated achieving a quick self-healing ability within 10 min, large deformation tolerance of over 7000%, superior conductivity of 11.76 S·cm-1 and anti-freezing ability, which is difficult to obtain simultaneously. Such hydrogel provides new opportunities for artificial electronic devices in harsh environments. As a prospective application, we fabricate an artificial nerve fiber by mimicking the structure and functions of the myelinated axon, exhibiting the property of fast and potential-gated signal transmission.
This artificial nerve fiber is integrated into a robot for demonstrating a real-time high fidelity and high throughput information interaction under big deformation and cryogenic temperature. The hydrogel and bionic device will bring pioneering functions for robots and open a broad application scenario in extreme conditions. This article is protected by copyright. All rights reserved.

Cryogenic temperature sensing based on the temperature dependence of color centers in optical fibers

A cryogenic temperature sensor based on the temperature dependence of stable color centers in a commercial single-mode optical fiber is proposed. The radiation induced attenuation spectra at different temperatures are measured and decomposed by Ge-NBOHC and Ge(X) color centers. The configurational coordinate model is used to explain the temperature properties of the color centers.
A series of experiments are conducted to evaluate its performance in the temperature range from 10°C to -196°C, and the results suggest that the temperature sensitivity is ∼0.17 dB/km/°C with a resolution of 0.034°C, and the nonlinearity and repeatability error are ±3.8% and 1.4%, respectively.

Revealing the Intrinsic Atomic Structure and Chemistry of Amorphous LiO 2-Containing Products in Li-O 2 Batteries Using Cryogenic Electron Microscopy

Aprotic lithium-oxygen batteries (LOBs) are promising energy storage systems characterized by ultrahigh theoretical energy density. Extensive research has been devoted to this battery technology, yet the detailed operational mechanisms involved, particularly unambiguous identification of various discharge products and their specific distributions, are still unknown or are subjects of controversy. This is partly because of the intrinsic complexity of the battery chemistry but also because of the lack of atomic-level insight into the oxygen electrodes acquired via reliable techniques. In the current study, it is demonstrated that electron beam irradiation could induce crystallization of amorphous discharge products. Cryogenic conditions and a low beam dosage have to be used for reliable transmission electron microscopy (TEM) characterization.
High-resolution cryo-TEM and electron energy loss spectroscopy (EELS) analysis of toroidal discharge particles unambiguously identified the discharge products as a dominating amorphous LiO2 phase with only a small amount of nanocrystalline Li2O2 islands dispersed in it. In addition, uniform mixing of carbon-containing byproducts is identified in the discharge particles with cryo-EELS, which leads to a slightly higher charging potential. The discharge products can be reversibly cycled, with no visible residue after full recharge. We believe that the amorphous superoxide dominating discharge particles can lead researchers to reconsider the chemistry of LOBs and pay special attention to exclude beam-induced artifacts in traditional TEM characterizations.
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Perspectives of farmers and tourists on agricultural abandonment in east Lesvos, Greece.

Perspectives of farmers and tourists on agricultural abandonment in east Lesvos, Greece.

Multi-stakeholder perceptions of panorama modifications are more and more acknowledged as important inputs to discussions on future panorama developments, significantly when addressing the way forward for European rural areas experiencing agricultural abandonment.

This analysis presents a case exploration of abandonment of olive plantations in east Lesvos, Greece. We carried out two units of semi-structured interviews to narrate an exploration on native farmers’ capacity and willingness to keep up the plantations, to the outcomes of a panorama choice survey undertaken with vacationers. Three farmer varieties are recognized following a cluster evaluation based mostly on attributes of particular person capacity and willingness to farm. Farmers belonging to the prevalent kind revealed low capacity and willingness and count on to additional extensify their farms.

The remaining two farmer varieties have greater willingness; they’re motivated by cultural causes, extra incessantly expressing a want to keep up their land underneath household possession, and partake in social cooperative initiatives selling practices valorizing the olive plantations. We define how these varieties work together with regional drivers of change, and partly additionally contribute to persistence of abandonment by way of constrained capacity to farm.

Abandonment doesn’t align with present panorama preferences of vacationers, who favor cultivated landscapes, components of traditionality inside constructed infrastructure and undertake nature-based actions. We focus on how excessive willingness to farm related to skilled and pluri-active types of farming could nevertheless present alternatives to keep up the cultivated panorama and synergize with (agri-)tourism demand. Our findings are corresponding to these of different European research, contributing to discussions on the way forward for its rural landscapes.

Perspectives of farmers and tourists on agricultural abandonment in east Lesvos, Greece.
Views of farmers and vacationers on agricultural abandonment in east Lesvos, Greece.

Immunophenotypic characterization, multi-lineage differentiation and growing older of zebrafish coronary heart and liver tissue-derived mesenchymal stem cells as a novel strategy in stem cell-based remedy.

Mesenchymal stem cells (MSCs) are a very good mannequin for preclinical and scientific investigations, and various sources of MSCs are topic to intensive experiments. On this examine, mesenchymal stem cells (MSCs) have been remoted from coronary heart and liver tissue of Zebrafish (Danio rerio). The flow-cytometry in addition to RT-PCR have been used to investigate the expression of a panel of cell floor markers CD44, CD90, CD31 and CD34.

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  1. Within the following, alizarin pink, oil red-O and toluidine blue staining have been carried out to judge the multi-lineage differentiation of zebrafish coronary heart and liver tissue-derived MSCs. Subsequently, the gene and protein expression of Oct4, Sox2 and Nanog as pluri

    -potent markers have been analyzed by RT-PCR and western blotting, respectively.

As well as, MTT assay was used for cell proliferation potential and inhabitants doubling time (PDT) evaluation. Additionally, the growing older of cells was investigated by β-galactosidase exercise assay. The outcomes confirmed that, like different MSCs, zebrafish coronary heart and liver tissue-derived MSCs have been constructive for mesenchymal, adverse for hematopoietic markers and expressed pluripotent markers Oct4, Sox2 and Nanog. Furthermore, these cells have been differentiated to osteocyte, adipocyte, and chondrocyte lineages following directed differentiation. It was discovered that PDT of zebrafish coronary heart and liver tissue-derived MSCs have been 50.67 and 46.61 h, respectively.

These cells had considerably extra speedy progress on day 4. Our outcomes present that zebrafish coronary heart and liver tissue-derived MSCs exhibited typical MSC traits together with fibroblast morphology, multi-lineage differentiation capability, pluriefficiency potential and expression of a typical set of basic MSC floor markers.