Studies of carbohydrate derivatives having the -CH2F function

The following primary sulphonates have been converted into the corresponding deoxyfluoro derivatives by reaction with potassium fluoride in ethylene glycol:1,2:3,4-di-O-isopropylidene-6-O-tosyl α-D-galactopyranose (1), methyl 2,3-O2-isopropyliden-5-O-tosyl-α,β-D-ribofuranoside (2), 1,2:3,4-di-O-methylene-6-O-tosyl-α-D-glucofuranose (3), 3,5-di-O-benzylidene-1,2-O-isopropylidene-6-O-tosyl-α-D-glucofuranose (4), and 1,2:3,5-di-O-isopropylidene-6-O-tosyl-α-D-glucofuranose (5). The yields were generally poor; in the reaction of 1, a major by-product was 6-O-(2-hydroxyethyl)-1,2:3,4-di-O-isopropylidene-α-D-galactopyranose (11). The reaction of the primary hydroxyl precursor of each of the above tosylates with N2-(2-chloro- 1,1,2-trifluoroethyl)-N,N-diethylamine generally yielded the O-chlorofluoroacetyl derivative; however, 1,2:3,5-di-O-methylene-α-D-glucofuranose (12) was converted into the 6-deoxy-6-fluoro derivative (8). The ¹⁹F resonances of compounds containing the CH₂F moiety fall between φ_C +213 and φ_C +235 p.p.m. The differences between the vicinal¹⁹F-¹H couplings of compounds having the D-gluco and D-galacto configurations clearly reflect the influence of the C-4O-4 substitutents on the populations of the C-5C-6 rotamers. A novel type of noise-modulated, heteronuclear decoupling experiment is described.     

Defining a functional unit for dairy production LCA that reflects the transaction between the farmer and the dairy processor

Purpose

The two main functions of dairy farming are to produce raw milk and to generate an economic income for the farmer (Powell et al. in Nutr Cycl Agroecosyst 82:107–115, 2008), both of which drive the downstream value chain. Farm profit is mainly determined by the quantity and quality of milk, and at the same time, dairy farmers have a responsibility for animal welfare and the protection of human health through milk hygiene. When dairy farmers supply milk to a processor, the payment is based on both the quantity and the quality in terms of composition (fat and protein) and hygiene (total bacterial count and somatic cell count). Somatic cell count reflects the health status of the mammary gland and contributes to reduced shelf life and reduced cheese yield and quality, whilst total bacterial count reflects herd health and farm sanitation. The objective of this work was to create a new functional unit for raw milk at the farm gate/ processor gate, which could be used to better capture the economic function of milk, while still reflecting the quality criteria captured by energy corrected milk and fat and protein corrected milk.

Materials and methods

Base price-adjusted milk (BPAM) is proposed as a functional unit to capture more of the functions of the transaction between the farmer and the processor. It expresses the volume of milk delivered as the equivalent volume at base price, such that greater milk solids increase the volume and poor hygiene decreases the volume. The BPAM was compared with energy-corrected milk and was tested using a survey of 54 farms in Ireland and eight scenarios compared with the observed values and an “ideal” scenario with no hygiene penalty imposed.

Results and discussion

It was found that kg BPAM for the sample of farms was strongly correlated with kg ECM because of the overall hygiene standard from the sample of farms available. For specific farms at specific times, the hygiene properties contributed to the economic function of the milk in a way that could not be captured using energy-corrected milk. The scenario analysis indicated that high levels of biological contamination, if captured in the raw milk functional unit, could increase carbon footprint by >?200%.

Conclusions

It was concluded that BPAM may not be a necessary functional unit for all studies, but those that focused on the farmer and processor perspectives should consider using BPAM because it captures more of the obligatory properties of raw milk than just quality expressed in terms of milk solids.

     

Liana cover in the canopies of rainforest trees is not predicted by local ground‐based measures

Lianas (woody climbers) are structural parasites of trees that compete with them for light and below‐ground resources. Most studies of liana–tree interactions are based on ground‐level observations of liana stem density and size, with these assessments generally assumed to reflect the amount of liana canopy cover and overall burden to the tree. We tested this assumption in a 1‐ha plot of lowland rainforest in tropical Australia. We recorded 1072 liana stems (≥1 cm diameter at breast height {dbh}) ha^?1 across all trees (≥10 cm dbh) on the plot and selected 58 trees for detailed study. We estimated liana canopy cover on selected trees that hosted 0–15 liana individuals, using a 47‐m‐tall canopy crane. Notably, we found no significant correlations between liana canopy cover and three commonly used ground‐based measurements of liana abundance as follows: liana stem counts per tree, liana above‐ground biomass per tree and liana basal area per tree. We also explored the role of tree size and liana infestation and found that larger trees (≥20 cm dbh) were more likely to support lianas and to host more liana stems than smaller trees (≤20 cm dbh). This pattern of liana stem density, however, did not correlate with greater liana coverage in the canopy. Tree family was also found to have a significant effect on likelihood of hosting lianas, with trees in some families 3–4 times more likely to host a liana than other families. We suggest that local ground‐based measures of liana–tree infestation may not accurately reflect liana canopy cover for individual trees because they were frequently observed spreading through neighbouring trees at our site. We believe that future liana research will benefit from new technologies such as high‐quality aerial photography taken from drones when the aim is to detect the relative burden of lianas on individual trees.     

The discovery of biaryl acids and amides exhibiting antibacterial activity against Gram-positive bacteria

Solid-phase synthetic methods for biaryl-based compounds were developed resulting in the construction of two 1000-member libraries. Numerous compounds were identified by high-throughput screening using whole cell screens to exhibit anti-microbial activity against Gram-positive bacteria. A series of biaryl compounds containing natural and unnatural amino acids were made to explore the SAR of the amino acid functionality.     

Detecting anthropogenic disturbance in tropical forests

Tropical forests are beleaguered by an array of threats driven by different scales of anthropogenic perturbations, which vary in the degree to which they can be detected by remote sensing. The extent of different patterns of cryptic disturbance often far exceeds the total area deforested, as shown by two recent studies on selective logging in Amazonia. Here, we discuss different forms of disturbance in Amazonian forests and question how much of the apparently intact forest in this region remains relatively undisturbed.     

Edge disturbance drives liana abundance increase and alteration of liana–host tree interactions in tropical forest fragments

Closed‐canopy forests are being rapidly fragmented across much of the tropical world. Determining the impacts of fragmentation on ecological processes enables better forest management and improves species‐conservation outcomes. Lianas are an integral part of tropical forests but can have detrimental and potentially complex interactions with their host trees. These effects can include reduced tree growth and fecundity, elevated tree mortality, alterations in tree‐species composition, degradation of forest succession, and a substantial decline in forest carbon storage. We examined the individual impacts of fragmentation and edge effects (0–100‐m transect from edge to forest interior) on the liana community and liana–host tree interactions in rainforests of the Atherton Tableland in north Queensland, Australia. We compared the liana and tree community, the traits of liana‐infested trees, and determinants of the rates of tree infestation within five forest fragments (23–58 ha in area) and five nearby intact‐forest sites. Fragmented forests experienced considerable disturbance‐induced degradation at their edges, resulting in a significant increase in liana abundance. This effect penetrated to significantly greater depths in forest fragments than in intact forests. The composition of the liana community in terms of climbing guilds was significantly different between fragmented and intact forests, likely because forest edges had more small‐sized trees favoring particular liana guilds which preferentially use these for climbing trellises. Sites that had higher liana abundances also exhibited higher infestation rates of trees, as did sites with the largest lianas. However, large lianas were associated with low‐disturbance forest sites. Our study shows that edge disturbance of forest fragments significantly altered the abundance and community composition of lianas and their ecological relationships with trees, with liana impacts on trees being elevated in fragments relative to intact forests. Consequently, effective control of lianas in forest fragments requires management practices which directly focus on minimizing forest edge disturbance.     

CORTICOTROPIN (ACTH) AND CORTISONE—Newer Concepts of Their Use in Clinical Practice

On the basis of three years'' experience with corticotropin and cortisone, it seems probable that the place of these hormones in clinical medicine will be one of increasing importance. At present they may be used to attain certain specific objectives:1. To return a large number of chronic invalids to a place of full activity in the community. This applies particularly to patients with rheumatoid arthritis and bronchial asthma. Many years of continuous therapy will be required in the majority of such patients.2. As life-saving agents in patients with certain diseases of unknown etiologic delineation that almost always cause death. In some patients treated for some of those diseases, therapy may eventually be discontinued.3. As life-saving agents (in conjunction with intensive antibiotic therapy) in patients with severe infections inadequately responsive to chemotherapy alone.Many of the untoward effects of hormonal therapy may be minimized or prevented by appropriate adjuvant measures.     

CLINICAL EXPERIENCE WITH CHLORPROPAMIDE

Seventy-eight patients with mild diabetes were treated with chlorpropamide in doses up to 1 gm. daily. Eight showed primary failure to respond and two showed an initial but not a sustained response. Patients whose diabetes was of recent onset and who had not been treated with insulin or a sulfonylurea, required smaller doses than the remainder except for a group of patients who had been diabetic for more than 15 years.The average dose for the 64 patients who took chlorpropamide for more than three months was 0.46 gm. per day. Serious side effects were uncommon and disappeared when the drug was stopped. One patient became jaundiced, one had a rash, and one showed granulocytopenia. Changes in liver function tests were seen in 17 out of 56 patients treated for more than three months and were correlated with the dosage of the drug and the duration of treatment.