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It has been established in numerous cases that proteins which are exported from Escherichia coli are synthesized on membrane-bound polysomes in precursor forms which are proteolytically cleaved to generate the mature species. Here we present evidence that at least one step in the export of proteins requires energy. Energy requirements for processing of the precursors of both the M13 coat protein [Date, T., Zwizinski, C., Ludmerer, S., and Wickner, W. (1980) Proc. Natl Acad. Sci. USA, 77, 827-831; Date, T., Goodman, J. M., and Wickner, W. T. (1980) Proc. Natl Acad. Sci. USA, 77, 4669-4673] and the B subunit of heat-labile enterotoxin [Palva, T., Hirst, T. R., Hardy, S. J. S., Holmgren, J., and Randall, L. L. (1981) J. Bacteriol. in the press] have been demonstrated previously. An energy requirement for the proteolytic processing of an additional five exported proteins is reported here. Studies utilizing an uncA mutant suggest that the form of energy required is proton-motive force. Thus an energized membrane is probably essential for export of most periplasmic and outer membrane proteins.

Beams with helical phasefronts described by exp(ilphi) carry an orbital angular momentum equivalent to lh per photon. Using diffractive optics this helical phase structure can be applied to every spectral component of the beam such that a spatially coherent white-light beam can carry orbital angular momentum without any chromatic distortion. This achromatic property can be hard to achieve in spin angular momentum where pure circular polarization is difficult to maintain across a finite spectral bandwidth. We illustrate the achromatic, helical phase structure of a white-light beam by observing the transfer of its orbital angular momentum to particles held in optical tweezers.

There is a need to create competency among Extension professionals on the topic of climate change adaptation and mitigation in animal agriculture. The Animal Agriculture in a Changing Climate online course provides an easily accessible, user-friendly, free, and interactive experience for learning science-based information on a national and regional level. The web-based curriculum is proving to be a useful tool and valuable resource for Extension educators in gaining knowledge and being better equipped to inform and influence livestock and poultry producers regarding climate issues.

For future landscapes to be sustainable, significant changes in land-use and management practices will be needed. This article argues that landscape archaeology can make distinctive contributions t...

5-hydroxymethylfurfural (HMF) is one of the most important renewable platform-chemicals, a very valuable precursor for the synthesis of bio-fuels and bio-products. In this work, the hydrogenation of HMF to two furan diols, 2,5-bis(hydroxymethyl)furan (BHMF) and 2,5-bis(hydroxymethyl)tetrahydrofuran (BHMTHF), both promising renewable monomers, was investigated. Three commercial catalysts, Ru/C, Pd/C and Pt/C, were tested in the hydrogenation of aqueous HMF solutions (2-3 wt%), using a metal loading of 1 wt% respect to HMF content. By appropriate tuning of the process conditions, either BHMF or BHMTHF were obtained in good yields, and Ru/C resulted the best catalyst for this purpose, allowing us to obtain BHMF or BHMTHF yields up to 93.0 and 95.3 mol%, respectively. This catalyst was also tested for in the hydrogenation of a crude HMF-rich hydrolyzate, obtained by one-pot the dehydration of fructose. The influence of each component of this hydrolyzate on the hydrogenation efficiency was investigated, including unconverted fructose, rehydration acids and humins, in order to improve the yields towards each furan diol. Moreover, ICP-OES and TEM analysis showed that the catalyst was not subjected to important leaching and sintering phenomena, as further confirmed by catalyst recycling study.

Abstract Microfibers (MFs) are released into the environment during the entire life of textile materials, from manufacturing to disposal. It is evident that micro-sized wastes are just as significant as macro-sized ones, and this issue should be prioritized. The use of textile waste in sound insulation materials is increasingly gaining attention. However, conventional sound absorption materials, such as fiberglass, polyurethane, and melamine foams, offer high-performance acoustic properties, but are derived from non-renewable resources and contribute to environmental degradation. This study aims to develop environmentally friendly fibrous sound absorption panels by reusing MF waste generated during textile finishing processes. Waste MFs used within the scope of the study were collected from a textile finishing process’ wastewater containing a variety of fibers, including wool, cotton, acrylic, polyamide, polyester, polypropylene, and viscose by filtration method and blended with polyester fiber as a binder. Then, acoustic panels were produced using a hot press technique by varying the panel thickness, density, and binder fiber ratio, and the physical, chemical, morphological, and acoustic properties of these panels were tested. Findings revealed that thickness emerged as a critical factor, with the thickest samples exhibiting the highest sound absorption coefficient (0.9 at 3000 Hz). Moreover, an increase in sample density correlated positively with enhanced sound absorption values, while the binder fiber ratio demonstrated a negative impact. Additionally, all samples exhibited hydrophobic characteristics, showcasing water resistance. The statistical analysis of sound absorption performance was conducted using one-way ANOVA and Tukey’s honestly significant difference test, with the results visualized through boxplots. Compared to conventional materials, the developed MF-based panels provide an eco-friendly alternative by reducing reliance on virgin synthetic materials while achieving competitive sound absorption properties. This study enables sustainable waste management in the textile industry and the reuse of MF waste, providing alternative and environmentally friendly solutions to currently used sound absorption materials. While the recyclability and reuse potential of these panels remain promising, further research is needed to evaluate their long-term mechanical performance, resistance to environmental degradation, and practical implementation in real-world applications. Future investigations should focus on optimizing large-scale production processes and assessing the environmental footprint of these materials throughout their lifecycle.

Induction systems have become increasingly more important and popular in our modern world and their application areas have widely expanded because of their high levels of safety and controllability. Today one important application of these induction systems is the inductive heating, which now finds use not only in conventional applications of point-source heating but also in new areas including all-surface heating with some degree of flexibility in localization. The efficiency of such emerging systems, especially in planar structures across an entire surface, however, has thus far been limited compared to conventional inductive heating. In this thesis, to address these problems, we show a new class of strongly coupled planar coils that enhance magnetic coupling in square lattice stacking by design and with phase difference application in operation. These coils can be tiled in two-dimensional arrays in a modular fashion or to cover an arbitrarily large continuous surface. In a proof-of-concept realization, we experimentally demonstrated that these proposed outer squircle-inner circular coils outperform the conventional coils of circular shape. Using square-arrayed coil architecture, here we also present all-surface induction systems achieving uniform and enhanced heating speed for all loading positions no matter what the misalignment of the heated vessel with respect to the coils is. In addition, to solve the problems of automatically detecting metals over the whole surface together with determining their exact positions, we introduce a new method that relies on simultaneous wireless measurement and tracking of inductance-resistance of the coils at multiple frequencies to identify those coupled with the metal targets to be detected in the system. While pinpointing the location of the targeted metals, the proposed technique also identifies their material types. For future ubiquitous all-surface systems, this approach allows for automated sensing of metal vessels and powering the loaded coils for the highest possible performance independent of the specific location of each vessel with respect to coils. These findings indicate that the proposed innovative modular and arrayed coils enable, for the first time, full degree of flexibility in localized inductive heating with space-invariance in all-surface heating. Yüksek seviyede güvenlilik ve kontrol edilebilirlik özelliklerinden dolayı indüksiyon sistemlerin günümüz modern dünyasında önemi artmakta ve bu sistemler daha popüler hale gelirken kullanım alanları da genişlemektedir. Bu tür indüksiyon sistemlerin önemli uygulamalarından biri ısıtmadır. İndüktif ısıtmanın geleneksel ısıtmanın yanısıra lokal ısıtmadan bir derece daha esnek olan tüm yüzey gibi yeni uygulamaları vardır. Ancak, geliştirilmekte olan bu sistemlerin, özellikle de tüm yüzeyde kullanılan düzlemsel yapıların, verimlilikleri geleneksel indüktif ısıtıcılara göre oldukça kısıtlıdır. Bu tezde, bu sorunlara yönelik, aralarında kuplajı yüksek tutulan düzlemsel yapıda yeni bobin sınıfları tarafımızca gösterilmektedir. Bu bobinlerin aralarındaki manyetik etkileşme tasarımda karesel istiflenmeleri ve çalışma esnasında faz farkı uygulanması ile artırılmaktadır. Bu bobinler iki boyutlu olarak modüler tarzda veya herhangi büyüklükteki ve kesintisiz bir yüzeyi kaplayacak şekilde döşenebilir. Kavramın ispatı gerçekleştirilirken, deneyler önerilen dış kısmı karesel-iç kısmı çembersel bobinlerin çember şeklindeki geleneksel bobinleri performansta geçtiğini gösterdi. Kare-dizi bobin mimarisi ile, bu tüm-yüzey indüksiyon sistemleri ile kap bobine göre tam hizalanmamış olsa dahi kabın bütün konumları için sabit ve yüksek hızda ısıtılması başarıldığı gösterildi. Buna ek olarak, metallerin yüzeyin tamamında otomatik olarak algılanması ve kesin konumunun belirlenmesi sorunlarının çözümüne yönelik, metallerle eşleşmiş bobinlerin algılanması ve tanımlanması için çoklu frekanslarda indüktans-rezistans değerlerinin eş zamanlı ve temassız ölçümüne dayanan yeni bir yöntem sunuldu. Önerilen bu yöntem ile metallerin konumları tam olarak saptanırken, aynı zamanda malzeme tipleri de tanımlanabilmektedir. Gelecekte her yerde kullanılabilecek tüm-yüzey sistemler için bu yaklaşım metal kapların otomatik olarak algılanmasını ve yüklü bobinlerin her bir kabın bobine göre konumundan bağımsız olarak en yüksek performansla sürülmesini sağlayacaktır. Bulgularımız göstermektedir ki, önerilen bu yenilikçi modüler ve dizi bobinler, ilk defa olarak, tüm-yüzey ısıtmada konumdan bağımsız olarak tam bir esneklikle indüktif ısıtmaya olanak sağlamaktadır. 169

AbstractThe impacts of the changing climate on the biological world vary across latitudes, habitats and spatial scales. By contrast, the time of day at which these changes are occurring has received relatively little attention. As biologically significant organismal activities often occur at particular times of day, any asymmetry in the rate of change between the daytime and night‐time will skew the climatic pressures placed on them, and this could have profound impacts on the natural world. Here we determine global spatial variation in the difference in the mean annual rate at which near‐surface daytime maximum and night‐time minimum temperatures and mean daytime and mean night‐time cloud cover, specific humidity and precipitation have changed over land. For the years 1983–2017, we derived hourly climate data and assigned each hour as occurring during daylight or darkness. In regions that showed warming asymmetry of >0.5°C (equivalent to mean surface temperature warming during the 20th century) we investigated corresponding changes in cloud cover, specific humidity and precipitation. We then examined the proportional change in leaf area index (LAI) as one potential biological response to diel warming asymmetry. We demonstrate that where night‐time temperatures increased by >0.5°C more than daytime temperatures, cloud cover, specific humidity and precipitation increased. Conversely, where daytime temperatures increased by >0.5°C more than night‐time temperatures, cloud cover, specific humidity and precipitation decreased. Driven primarily by increased cloud cover resulting in a dampening of daytime temperatures, over twice the area of land has experienced night‐time warming by >0.25°C more than daytime warming, and has become wetter, with important consequences for plant phenology and species interactions. Conversely, greater daytime relative to night‐time warming is associated with hotter, drier conditions, increasing species vulnerability to heat stress and water budgets. This was demonstrated by a divergent response of LAI to warming asymmetry.