Characteristics of C-4 photosynthesis in stems and petioles of C-3 flowering plants

Most plants are known as C-3 plants because the first product of photosynthetic CO2 fixation is a three-carbon compound. C-4 plants, which use an alternative pathway in which the first product is a four-carbon compound, have evolved independently many times and are found in at least 18 families. In addition to differences in their biochemistry, photosynthetic organs of C-4 plants show alterations in their anatomy and ultrastructure. Little is known about whether the biochemical or anatomical characteristics of C-4 photosynthesis evolved first. Here we report that tobacco, a typical C-3 plant, shows characteristics of C-4 photosynthesis in cells of stems and petioles that surround the xylem and phloem, and that these cells are supplied with carbon for photosynthesis from the vascular system and not from stomata. These photosynthetic cells possess high activities of enzymes characteristic of C-4 photosynthesis, which allow the decarboxylation of four-carbon organic acids from the xylem and phloem, thus releasing CO2 for photosynthesis. These biochemical characteristics of C-4 photosynthesis in cells around the vascular bundles of stems of C-3 plants might explain why C-4 photosynthesis has evolved independently many times

From data to draught: Modelling and predicting mixed-culture beer fermentation dynamics using autoregressive recurrent neural networks

The ascendency of the craft beer movement within the brewing industry may be attributed to its commitment to unique flavours and innovative styles. Mixed-culture fermentation, celebrated for its novel organoleptic profiles, presents a modelling challenge due to its complex microbial dynamics. This study addresses the inherent complexity of modelling mixed-culture beer fermentation while acknowledging the condition monitoring limitations of craft breweries, namely sporadic offline sampling rates and limited available measurement parameters. A data-driven solution is proposed, utilising an Autoregressive Recurrent Neural Network (AR-RNN) to facilitate the production of novel, replicable, mixed-culture fermented beers. This research identifies time from pitch, specific gravity, pH, and fluid temperature as pivotal model parameters that are cost-effective for craft breweries to monitor offline. Notably, the autoregressive RNN fermentation model is generated using high-frequency multivariate data, a departure from intermittent offline measurements. Employing the trained autoregressive RNN framework, we demonstrate its robust forecasting prowess using limited offline input data, emphasising its ability to capture intricate fermentation dynamics. This data-driven approach offers significant advantages, showcasing the model’s accuracy across various fermentation configurations. Moreover, tailoring the design to the craft beer market’s unique demands significantly enhances the model’s practicable predictive capabilities. It empowers nuanced decision-making in real-world mixed-culture beer production. Furthermore, this model lays the groundwork for future studies, highlighting transformative possibilities for cost-effective model-based control systems in the craft beer sector.</jats:p

Biotin carboxyl carrier protein and carboxyltransferase subunits of the multi-subunit form of acetyl-CoA carboxylase from \u3ci\u3eBrassica napus\u3c/i\u3e: cloning and analysis of expression during oilseed rape embryogenesis

In the oilseed rape Brassica napus there are two forms of acetyl- CoA carboxylase (ACCase). As in other dicotyledonous plants there is a type I ACCase, the single polypeptide 220 kDa form, and a type II multi-subunit complex analogous to that of Escherichia coli and Anabaena. This paper describes the cloning and characterization of a plant biotin carboxyl carrier protein (BCCP) from the type II ACCase complex that shows 61% identity/79% similarity with Anabaena BCCP at the amino acid level. Six classes of nuclear encoded oilseed rape BCCP cDNA were cloned, two of which contained the entire coding region. The BCCP sequences allowed the assignment of function to two previously unassigned Arabidopsis expressed sequence tag (EST) sequences. We also report the cloning of a second type II ACCase component from oilseed rape, the β-carboxyltransferase subunit (βCT), which is chloroplast-encoded. Northern analysis showed that although the relative levels of BCCP and βCT mRNA differed between different oilseed rape tissues, their temporal patterns of expression were identical during embryo development. At the protein level, expression of BCCP during embryo development was studied by Western blotting, using affinity-purified anti-biotin polyclonal sera. With this technique a 35 kDa protein thought to be BCCP was shown to reside within the chloroplast. This analysis also permitted us to view the differential expression of several unidentified biotinylated proteins during embryogenesis

Design of InP membrane SOA with butt-joint active passive interface

A butt-joint SOA design for InP on Si membrane (IMOS) platform is proposed. The new design features the butt-joint interface between the SOA and passive nanophotonic waveguide, which makes the interface a factor of 2 to 6 shorter than in the current twin-guide SOAs, with possibility to reduce it further to factor of 5-10. This makes the new SOA a promising candidate for high-speed directly modulated lasers (DML) applications, where extremely short SOAs (40-100 μm long) and short distances between reflectors are usually required

Food Packaging and Bisphenol A and Bis(2-Ethyhexyl) Phthalate Exposure: Findings from a Dietary Intervention

Background: Bisphenol A (BPA) and bis(2-ethylhexyl) phthalate (DEHP) are high-production-volume chemicals used in plastics and resins for food packaging. They have been associated with endocrine disruption in animals and in some human studies. Human exposure sources have been estimated, but the relative contribution of dietary exposure to total intake has not been studied empirically

Herbal medicine: women's views, knowledge and interaction with doctors: a qualitative study

BACKGROUND: There is growing concern that serious interactions are occurring between prescribed/over the counter and herbal medicines and that there is a lack of disclosure of herbal use by patients to doctors. This study explores women's perspectives about the safety of herbal remedies, herb-drug interactions and communication with doctors about herbal medicines. METHODS: Qualitative, cross-sectional study, with purposive sampling which took place in Cheshire, UK. Eighteen in depth semi-structured interviews were conducted with female herbal medicine users aged 18 years and above. RESULTS: The large majority did not inform their GPs of their use of herbal medicines. This was due to lack of physician enquiry, perception of importance and fear of a negative response. Several women were not aware that herbal remedies could interact with prescribed or over the counter medicines. Of the women who had experienced adverse effects none had reported them, believing them of low importance. CONCLUSION: The women had little knowledge about herb-drug interactions and rarely disclosed use of herbal medicines to their doctor. Doctors' communication and openness regarding herbal medicines needs to improve and there should be increased access to accurate information on herbal medicines in the public and health care domain

The prevalence, patterns of usage and people's attitude towards complementary and alternative medicine (CAM) among the Indian community in Chatsworth, South Africa

BACKGROUND: The purpose of this study was to determine, among the Indian community of Chatsworth, South Africa, the prevalence and utilisation patterns of complementary and alternative medicine (CAM), attitudes associated with CAM use and communication patterns of CAM users with their primary care doctors. METHODS: Face-to-face structured interviews were conducted in Chatsworth, a suburb of Durban in which South Africans of Indian origin predominantly reside. Participants were 200 randomly selected adult English-speaking Indian residents. RESULTS: The prevalence of CAM usage for period 2000/2001 was 38.5% (95% confidence interval 31.7% to 45.6%). Spiritual healing and herbal/natural medicines, including vitamins were the most common types of CAM used, accounting for 42.8% and 48.1% respectively of overall CAM usage. People used CAM to treat conditions including diabetes mellitus, headaches, arthritis and joint pains, stress, skin disorders, backaches, hypertension and nasal disorders. Half of the CAM users used allopathic medicines concurrently. The cost of CAM utilization over this 1-year period, incurred by 80.5% of users for the duration of therapy for their most troublesome condition was below R500 (approximately US$50). Age, sex, marital status, religion, level of education and income were shown not to influence the use of CAM. Greater than half (51.9%) of CAM users did so either upon the advice of someone they knew, or after noticing a CAM advertisement in the local press. Seventy-nine percent of CAM users indicated that they had positive outcomes with their treatments. Fifty four percent of CAM users (excluding those using spiritual healing only) failed to inform their doctors that they used CAM. The main reason given by half of this group was that informing their doctors did not seem necessary. CONCLUSION: The prevalence of CAM in Chatsworth is similar to findings in other parts of the world. Although CAM was used to treat many different ailments, this practice could not be attributed to any particular demographic profile. The majority of CAM users were satisfied with the effects of CAM. Findings support a need for greater integration of allopathic medicine and CAM, as well as improved communication between patients and caregivers regarding CAM usage