We produce gold nanoparticle dimers with a surface-to-surface distance that varies reversibly by a factor of 3 when hybridizing or removing a single target DNA strand. The dimers are built on one DNA template that features a stem-loop enabling the interparticle distance change. Using electrophoresis, we reach 90% sample purities and demonstrate that this chemical process is reversible in solution at room temperature for a low molar excess of the target DNA strand. The kinetics of the reaction is asymmetric due to steric hindrance in the stem-loop opening process. Furthermore, a statistical analysis of cryo-electron microscopy measurements allows us to provide the first quantitative analysis of distance changes in chemically switchable nanoparticle assemblies.
Biodegradable polymer composites from renewable resources are the next-generation of wood-like materials and are crucial for the development of various industries to meet sustainability goals. Functional applications like packaging, medicine, automotive, construction and sustainable housing are just some that would greatly benefit. Some of the existing industries, like wood plastic composites, already encompass given examples but are dominated by fossil-based polymers that are unsustainable. Thus, there is a background to bring a new perspective approach for the combination of microcrystalline cellulose (MCC) and nanofibrillated cellulose (NFC) fillers in bio-based poly (butylene succinate) matrix (PBS). MCC, NFC and MCC/NFC filler total loading at 40 wt % was used to obtain more insights for wood-like composite applications. The ability to tailor the biodegradable characteristics and the mechanical properties of PBS composites is indispensable for extended applications. Five compositions have been prepared with MCC and NFC fillers using melt blending approach. Young’s modulus in tensile test mode and storage modulus at 20 °C in thermo-mechanical analysis have increased about two-fold. Thermal degradation temperature was increased by approximately 60 °C compared to MCC and NFC. Additionally, to estimate the compatibility of the components and morphology of the composite’s SEM analysis was performed for fractured surfaces. The contact angle measurements testified the developed matrix interphase. Differential scanning calorimetry evidenced the trans-crystallization of the polymer after filler incorporation; the crystallization temperature shifted to the higher temperature region. The MCC has a stronger effect on the crystallinity degree than NFC filler. PBS disintegrated under composting conditions in a period of 75 days. The NFC/MCC addition facilitated the specimens’ decomposition rate up to 60 days
Background: Currently, there are few data on the association between participation in soccer and the condition of the knee joints in adult professional players. Hypothesis: A high percentage of professional soccer players will have asymptomatic intra-articular changes of the knee. Study Design: Cross-sectional study; Level of evidence, 3. Methods: The condition of the intra-articular structures (osteophytes, cartilage, and menisci) in 94 knee joints of 47 adult professional soccer players (mean ± SD age, 25.7 ± 4.6 years; body mass index, 22.8 ± 1.4 kg/m2) was analyzed. A 1.5-T magnetic resonance imaging scanner was used to perform the imaging, and the anonymized data were analyzed by 2 experienced radiologists. Results: Cartilage of both knee joints was affected in 97.9% of soccer players. Meniscal lesions were detected in 97.8% of joints, affecting both joints in 93.6% of athletes. Grade 2 cartilage lesions were the most prevalent (36%-60% depending on the lesion site), and grade 4 lesions were detected in 12.7% of joints. The medial femoral condyle and medial tibial plateau were most frequently affected by cartilage lesions (85.1%). Among meniscal lesions, grade 2 lesions were the most prevalent, being detected in 71% of the cases. Grade 3 lesions were detected in 13.8% of the joints. The posterior horn of the lateral meniscus was the most common site of meniscal lesions (affected in 95.7% of the joints). Osteophytes were detected in 4.2% of joints. Conclusion: The prevalence of asymptomatic cartilage and meniscal lesions in the knees of adult professional soccer players is extremely high and is not associated with the reduction of sports involvement. This research should promote the correct interpretation of magnetic resonance imaging data obtained from soccer players with acute trauma and the reduction of the number of unwarranted surgical procedures.
To take full advantage of the reagent- and label-free sensing capabilities
of electrochemical sensors, a frequent and remaining challenge is
interference and degradation of the sensors due to uncontrolled pH
or salinity in the sample solution or foulants from the sample solution.
Here, we present an oil-membrane sensor protection technique that
allows for the permeation of hydrophobic (lipophilic) analytes into
a sealed sensor compartment containing ideal salinity and pH conditions
while simultaneously blocking common hydrophilic interferents (proteins,
acids, bases, etc.) In this paper, we validate the oil-membrane sensor
protection technique by demonstrating continuous cortisol detection
via electrochemical aptamer-based (EAB) sensors. The encapsulated
EAB cortisol sensor exhibits a 5 min concentration-on rise time and
maintains a measurement signal of at least 7 h even in the extreme
condition of an acidic solution of pH 3.
Complying with certain requirements or, more precisely, following the guidelines for the design of a scientific publication helps to make it not only more comprehensible for reviewers and readers, but actually enhances the quality of work. For example, even if some aspects in design logic were fulfilled but not described, other researchers doing meta-analysis may wrongly but for a good reason downgrade such publication and exclude it from the analysis. Understanding of the guidelines for study design ensures not only the proper description of the results but the initial planning of work. The CA RE guidelines were established for reporting of clinical cases, STROBE — for reporting observational studies (cohort and case-control studies), CO NSORT — for reporting randomized studies (these guidelines are often used also for other comparative and case series studies), STARD — for reporting diagnostic studies, and PRISMA — for reporting of systematic reviews and meta-analyses. The present paper describes the key aspects of those guidelines and provides templates for graphic display of study design in form of flow charts. Evidently, we should not forget that each study is unique and there is always a place for a reasonable compromise between “requirements” and the real logic of the research in place.
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