Shift In Proportion Research Articles

From citizen science to citizen action: analysing the potential for a digital platform to cultivate attachments to nature

Identifying private gardens in the U.K. as key sites of environmental engagement, we look at how a longer-term online citizen science programme facilitated the development of new and personal attachments of nature. These were visible through new or renewed interest in wildlife-friendly gardening practices and attitudinal shifts in a large proportion of its participants. Qualitative and quantitative data, collected via interviews, focus groups, surveys and logging of user behaviours, revealed that cultivating a fascination with species identification was key to both ‘helping nature’ and wider learning, with the programme creating a space where scientific and non-scientific knowledge could co-exist and reinforce one another.

Space use patterns of the burrowing echimyid rodent, Clyomys laticeps

AbstractSpace use patterns of a population are a result of the set of movements of its individuals, which are directly influenced by their attributes and environmental conditions. Understanding space use patterns and its determinants may give us insights about a species’ ecology, social and mating systems. Although echimyid rodents display a variety of mating and social systems, movements of burrowing species are poorly studied due to their cryptic habits. Hence, in this study, we evaluated the effects of body mass, sex, and palm fruit availability on space use patterns of the burrowing echimyid Clyomys laticeps, by measuring their daily home range (DHR) and intensity of habitat use. In 9 months of study in a “cerrado campo sujo” site, we tracked 14 adults with the spool‐and‐line in a backpack method. Adult males had larger DHR size than females, probably as a response to greater body mass and reproductive behavior. Furthermore, adult females had greater intensity of habitat use, presenting site fidelity, which can be due to offspring care as a response to non‐seasonal reproduction observed in our study and/or due to nest site defense strategy to avoid energetic costs associated with burrow construction. Differently from expected, food availability (i.e., Allagoptera campestris palm fruits) had no influence on the space use patterns of C. laticeps. As in other herbivorous rodents, shifts in proportion of consumed food items according to their availability may explain the lack of this influence in our study. Our findings suggest that space use patterns of C. laticeps are mainly explained by behavioral and physiological differences between sexes, including body mass and reproductive strategies. Additionally, larger male movements and female site fidelity suggest a solitary behavior and a polygynous mating system, although further studies regarding spatial organization and genetic structure are necessary to support these suggestions.

Evaluation of variability in human kidney organoids

The utility of human pluripotent stem cell-derived kidney organoids relies implicitly on the robustness and transferability of the protocol. Here we analyze the sources of transcriptional variation in a specific kidney organoid protocol. Although individual organoids within a differentiation batch showed strong transcriptional correlation, we noted significant variation between experimental batches, particularly in genes associated with temporal maturation. Single-cell profiling revealed shifts in nephron patterning and proportions of component cells. Distinct induced pluripotent stem cell clones showed congruent transcriptional programs, with interexperimental and interclonal variation also strongly associated with nephron patterning. Epithelial cells isolated from organoids aligned with total organoids at the same day of differentiation, again implicating relative maturation as a confounder. This understanding of experimental variation facilitated an optimized analysis of organoid-based disease modeling, thereby increasing the utility of kidney organoids for personalized medicine and functional genomics.

Effect of hydrogen concentration on graphene synthesis using microwave-driven plasma-mediated methane cracking

Gas phase graphene forms as an aerosol in a microwave plasma among other carbon forms. Consisting of 2–6 sheets per stack with dimensions between 100 and 500 nm, it is referred to as nanographene (NG). Surprisingly, increasing H/C ratio in the feedstock increases the relative graphitic content of the product. Dependence of the different carbon forms upon H/C ratio of the gas feed mixture is shown across multiple analytical characterizations. Attributes of (a) phase quality (pristine nature of NG) and (b) phase quantity (how much NG forms relative to other carbon sp2 phases) are addressed. Phase identification of the forms is performed via transmission electron microscopy with quantification by thermogravimetric analysis, assessing their respective oxidative reactivity benchmarked to commercially available similar carbon products applied as standards. X-ray diffraction differentiates these forms based on varied extent of graphitic structure. Electron energy loss spectroscopy assesses graphitic content by the ratio of sp2/sp3 bonding. Raman spectroscopy supports the observed shift in relative proportions of the carbon forms towards preferential graphitic content with increasing H/C. Selected area diffraction illustrates this for NG. Fringe analyses of nanostructure quantifies this shift for carbon particles. Infra-red spectroscopy reveals complementary CH bonding as a measure of graphitic quality.

ANALISIS PERANAN KATEGORI EKONOMI BASIS DAN EFISIENSI PERTAMBAHAN INVESTASI DI KABUPATEN MINAHASA UTARA

This research aims to analyze the role of the categorical or economic base sector as well as to observe the efficiency of investment accumulation in North Minahasa Regency. This research was conducted in the area of North Minahasa Regency, North Sulawesi Province. The study began in April until October 2018. This research was conducted in the area of North Minahasa Regency, North Sulawesi Province. The study began in April until October 2018. This research employs secondary data from Regional Gross Domestic Product (RGDP) based on the constant price in North Minahasa Regency and North Sulawesi Province and the data from The Change of Regional Gross Fixed Capital in North Minahasa Regency. The instrument used in this research is Location Quotient (LQ), Shift Share Analysis, and Incremental Capital Output Ratio. Results from LQ show that the category of agriculture, forestry, and fishery, mining and excavation, manufacture, construction, electricity and gas, real estate and education service serve the base category in North Minahasa Regency, with the value of LQ above 1. The role of base category shows positive result towards the formation of the Regional Gross Domestic Product in North Minahasa Regency, agriculture and forestry and fishery are the biggest contributor in RGDP of North Minahasa Regency during the period of 2013-2017. The role of base category through regional share towards North Sulawesi Province also shows positive results, thus base category in North Minahasa Regency contributes to the formation of RGDP in North Sulawesi Province. In the calculation of proportional shift, several base categories in North Minahasa Regency received negative values, namely agriculture, forestry and fishery, manufacture, and education service. Then, in the calculation of differential shift, electronics and gas is the only sector which receives negative value or is not able to compete with similar category in the provincial level. Also, the calculation of Incremental Capital Output Ratio as the instrument of the efficiency of capital income in North Minahasa Regency in the period of 2013-2017 which is calculated by the standard method to lag0, lag1 as well as the mean calculation method, show the result of ICOR which can be categorized as not efficient.

Quantitative assessment of cell population diversity in single-cell landscapes.

Single-cell RNA sequencing (scRNA-seq) has become a powerful tool for the systematic investigation of cellular diversity. As a number of computational tools have been developed to identify and visualize cell populations within a single scRNA-seq dataset, there is a need for methods to quantitatively and statistically define proportional shifts in cell population structures across datasets, such as expansion or shrinkage or emergence or disappearance of cell populations. Here we present sc-UniFrac, a framework to statistically quantify compositional diversity in cell populations between single-cell transcriptome landscapes. sc-UniFrac enables sensitive and robust quantification in simulated and experimental datasets in terms of both population identity and quantity. We have demonstrated the utility of sc-UniFrac in multiple applications, including assessment of biological and technical replicates, classification of tissue phenotypes and regional specification, identification and definition of altered cell infiltrates in tumorigenesis, and benchmarking batch-correction tools. sc-UniFrac provides a framework for quantifying diversity or alterations in cell populations across conditions and has broad utility for gaining insight into tissue-level perturbations at the single-cell resolution.

A systems biology approach to explore the impact of maple tree dormancy release on sap variation and maple syrup quality

Maple sap is a complex nutrient matrix collected during spring to produce maple syrup. The characteristics of sap change over the production period and its composition directly impacts syrup quality. This variability could in part be attributed to changes in tree metabolism following dormancy release, but little is known about these changes in deciduous trees. Therefore, understanding the variation in sap composition associated with dormancy release could help pinpoint the causes of some defects in maple syrup. In particular, a defect known as “buddy”, is an increasing concern for the industry. This off-flavor appears around the time of bud break, hence its name. To investigate sap variation related to bud break and the buddy defect, we monitored sap variation with respect to a dormancy release index (Sbb) and syrup quality. First, we looked at variation in amino acid content during this period. We observed a shift in amino acid relative proportions associated with dormancy release and found that most of them increase rapidly near the point of bud break, correlating with changes in syrup quality. Second, we identified biological processes that respond to variation in maple sap by performing a competition assay using the barcoded Saccharomyces cerevisiae prototroph deletion collection. This untargeted approach revealed that the organic sulfur content may be responsible for the development of the buddy off-flavor, and that dormancy release is necessary for the appearance of the defect, but other factors such as microbial activity may also be contributing.

Stable C and N Isotope Composition of Primary Producers and Consumers Along an Estuarine Salinity Gradient: Tracing Mixing Patterns and Trophic Discrimination

The mixing pattern along a summer salinity gradient in the estuary Odense Fjord was evaluated using nutrient concentrations as well as 13C and 15N isotope signatures of suspended and sediment organic matter, immobile macrophytes (Fucus vesiculosus and Ruppia maritima), and benthic fauna (Mya arenaria, Hediste (Nereis) diversicolor, and Arenicola marina). Trophic discrimination (Δ13C and Δ15N) of the infaunal consumers (suspension feeders and detritivores) was assessed from the obtained mixing patterns along the estuarine gradient. Correspondence between salinity, DIC, and DIN in Odense Fjord implies conservative mixing as also evident from linear relationships between salinity and δ13C and δ15N signatures of most living organic pools. Isotope signatures of suspended organic matter (i.e., diatoms) indicate that the river to marine DIC and DIN end-members have daily/weekly δ13C and δ15N averages during summer from − 10 to 0‰ and 10–12 to 0–5‰, respectively. Stable isotope signatures of long-lived macrophytes stationary at specific locations in Odense Fjord showed δ13C levels that were about 7‰ higher than for suspended particles and 3–4‰ higher than for sediment organic matter, while no such difference was evident for δ15N. The food of invertebrate consumers (M. arenaria, H. diversicolor, and A. marina) determined from the estuarine δ13C and δ15N patterns provided the first ever reported trophic discrimination of these animals. Thus, Δ13C was 1.9, 1.6, and 1.3‰ and Δ15N was 4.4, 5.0, and 3.5‰ for the three species, respectively. Accordingly, benthic suspension and deposit feeders in Odense Fjord are largely supported by a diet consisting of benthic and pelagic microalgae, however, with a possible slight shift in diet proportions or to other food sources in the lower reaches of the estuarine gradient.

Control charts to monitor rates and proportions

AbstractIn this paper, we call attention for monitoring proportions and rates when they are not results of Bernoulli experiments. To deal with this problem, usually control charts based on Beta distributions are built as this distribution is a well‐known one. However, in practice, there are other distributions to be considered as Simplex and Unit Gamma distributions. The impact of the speed to signal a shift in the average proportion in terms of out‐of‐control average run length is measured when the control limits determined under a Beta distribution is equivocally used to monitor individual rates from Simplex or Unit Gamma distributions or vice versa.

Patterns of long-term dynamics of aquatic communities and water quality parameters in the Great Lakes: Are they synchronized?

Long time series data can provide insights into dynamics of large lakes. We use the USEPA-GLNPO biological monitoring dataset (phytoplankton, benthos, zooplankton and water quality), collected from 1996 through 2016, to identify whether there is evidence of concordant linear or non-linear trends in community composition, density/biomass/biovolume and major environmental parameters. We show changes in biotic assemblages and water quality variables, particularly in Lakes Michigan and Huron. These include changes in phytoplankton biovolume and zooplankton biomass, increasing invasive Dreissena abundance and decreasing densities of other benthos. Biotic changes are accompanied by pronounced changes in water quality and nutrient ratios. Species change-points, identified using threshold indicator taxon analysis, are often less abrupt, but there are clear shifts in a large proportion of species in each assemblage. The concordance of breakpoints among assemblages or lack thereof provides valuable insight into potential drivers of ecosystem change.

Poorly cytotoxic terminally differentiated CD56negCD16pos NK cells accumulate in Kenyan children with Burkitt lymphomas

AbstractNatural killer (NK) cells are critical for restricting viral infections and mediating tumor immunosurveillance. Epstein-Barr virus (EBV) and Plasmodium falciparum malaria are known risk factors for endemic Burkitt lymphoma (eBL), the most common childhood cancer in equatorial Africa. To date, the composition and function of NK cells have not been evaluated in eBL etiology or pathogenesis. Therefore, using multiparameter flow cytometry and in vitro killing assays, we compared NK cells from healthy children and children diagnosed with eBL in Kenya. We defined 5 subsets based on CD56 and CD16 expression, including CD56negCD16pos. We found that licensed and terminally differentiated perforin-expressing CD56negCD16pos NK cells accumulated in eBL children, particularly in those with high EBV loads (45.2%) compared with healthy children without (6.07%) or with (13.5%) malaria exposure (P = .0007 and .002, respectively). This progressive shift in NK cell proportions was concomitant with fewer CD56dimCD16pos cells. Despite high MIP-1β expression, CD56negCD16pos NK cells had diminished cytotoxicity, with lower expression of activation markers NKp46, NKp30, and CD160 and the absence of TNF-α. Of note, the accumulation of poorly cytotoxic CD56negCD16pos NK cells resolved in long-term eBL survivors. Our study demonstrates impaired NK cell–mediated immunosurveillance in eBL patients but with the potential to restore a protective NK cell repertoire after cancer treatment. Characterizing NK cell dysfunction during coinfections with malaria and EBV has important implications for designing immunotherapies to improve outcomes for children diagnosed with eBL.

Genome mining for peptidases in heat-tolerant and mesophilic fungi and putative adaptations for thermostability

BackgroundPeptidases (EC 3.4) consist of a large group of hydrolytic enzymes that catalyze the hydrolysis of proteins accounting for approximately 65% of the total worldwide enzyme production. Peptidases from thermophilic fungi have adaptations to high temperature that makes them adequate for biotechnological application. In the present study, we profiled the genomes of heat-tolerant fungi and phylogenetically related mesophilic species for genes encoding for peptidases and their putative adaptations for thermostability.ResultsWe generated an extensive catalogue of these enzymes ranging from 241 to 820 peptidase genes in the genomes of 23 fungi. Thermophilic species presented the smallest number of peptidases encoding genes in relation to mesophilic species, and the peptidases families with a greater number of genes were the most affected. We observed differences in peptidases in thermophilic species in comparison to mesophilic counterparts, at (i) the genome level: a great reduction in the number of peptidases encoding genes that harbored a higher number of copies; (ii) in the primary protein structure: shifts in proportion of single or groups of amino acids; and (iii) in the three-dimensional structure: reduction in the number of internal cavities. Similar results were reported for extremely thermophilic proteins, but here we show for the first time that several changes also occurred on the moderate thermophilic enzymes of fungi. In regards to the amino acids composition, peptidases from thermophilic species in relation to the mesophilic ones, contained a larger proportion of Ala, Glu, Gly, Pro, Arg and Val residues and a lower number of Cys, His, Ile, Lys, Met, Asn, Gln, Ser, Thr and Trp residues (P < 0.05). Moreover, we observed an increase in the proportion of hydrophobic and charged amino acids and a decrease in polar amino acids.ConclusionsAlthough thermophilic fungi present less genes encoding for peptidases, these have adaptations that could play a role in thermal resistance from genome to protein structure level.

Center of gravity estimation using a reaction board instrumented with fiber Bragg gratings

The purpose of the present work is to construct a reaction board based on fiber Bragg gratings (FBGs) that could be used for estimation of the 2D coordinates of the projection of center of gravity (CG) of an object. The apparatus is consisted of a rigid equilateral triangular board mounted on three supports at the vertices, two of which have cantilevers instrumented with FBGs. When an object of known weight is placed on the board, the bending strain of the cantilevers is measured by a proportional wavelength shift of the FBGs. Applying the equilibrium conditions of a rigid body and proper calibration procedures, the wavelength shift is used to estimate the vertical reaction forces and moments of force at the supports and the coordinates of the object’s CG projection on the board. This method can be used on a regular basis to estimate the CG of the human body or objects with complex geometry and density distribution. An example is provided for the estimation of the CG projection coordinates of two orthopaedic femur bone models, one intact, and the other with a hip stem implant encased. The clinical implications of changing the normal CG location by means of a prosthesis have been discussed.

Effects of exogenous fibrolytic enzyme supplementation to diets with different NFC/NDF ratios on the growth performance, nutrient digestibility and ruminal fermentation in Chinese domesticated black goats

This study was conducted to evaluate the effects of exogenous fibrolytic enzymes (EFE) supplementation into diets with different non-fiber carbohydrates (NFC)/neutral detergent fiber (NDF) ratios on growth performance, nutrient digestibility, ruminal fermentation, and microbiome in Chinese domesticated Lezhi black goats. Treatments were 2 × 2 factorial arrangement of diets using low vs. high NFC/NDF ratios (1.06 or 1.66) and with or without EFE supplementation (0 or 0.4 g cellulase and xylanase/kg dry matter of diet). Sixty four Lezhi black goats (11 ± 0.8 kg of live weight) were randomly assigned to the four treatments. High NFC/NDF ratio and EFE supplementation achieved greater average daily gain and improve feed conversion ratio (P < .05). The same treatments also significantly increased digestibility of organic matter (OM), acid detergent fiber (ADF) and NDF. In addition, the high NFC/NDF ratio diet, but not the EFE supplement, improved digestibility of crude protein (CP) and reduced ruminal pH (P < .001). Both high NFC/NDF ratio and EFE supplement decreased ruminal NH3-N concentrations significantly (P < .001), and increased the production of rumen total volatile fatty acids (VFA, P < .001), especially the molar proportion of propionate (P < .05). They reduced the molar proportion of acetate and thus the ratio of acetate to propionate (A: P) (P < .05). Both the high NFC/NDF ratio and the EFE supplement elevated the levels of microbial crude proteins (P < .01). Importantly, the combination of high NFC/NDF ratio and the EFE supplement diet raised the content of the microbial crude proteins to the highest levels among the 4 different treatment groups (P = .012). However, the high NFC/NDF ratio and the EFE supplementation had different impacts on fiber degrading activities. The high NFC/NDF ratio diet decreased, while EFE supplementation increased, the activities of cellulase and xylanase (P < .05). Among the three cellulytic bacteria detected (Ruminococcus albus, Ruminococcus flavefaciens, Fibrobacter succinogenes), only the abundance of Fibrobacter succinogenes was significantly decreased with the high NFC/NDF ratio (P = .004). These results illustrate that the diet with a high NFC/NDF ratio and EFE supplementation can improve ADG, feed conversion ratio and nutrient utilization in Lezhi black goats. These improvements are likely attributed to the elevated production of microbial crude proteins and a shift in the molar proportions of VFA in the rumen, rather than increase of cellulolytic bacteria in the rumen microbiota.

Exposure to fine and ultrafine particulate matter during gestation alters postnatal oligodendrocyte maturation, proliferation capacity, and myelination

Accumulating studies indicate that the brain is a direct target of air pollution exposure during the fetal period. We have previously demonstrated that exposure to concentrated ambient particles (CAPs) during gestation produces ventriculomegaly, periventricular hypermyelination, and enlargement of the corpus callosum (CC) during postnatal development in mice. This study aimed to further characterize the cellular basis of the observed hypermyelination and determine if this outcome, among other effects, persisted as the brain matured. Analysis of CC-1+ mature oligodendrocytes in the CC at postnatal days (PNDs) 11–15 suggest a premature maturational shift in number and proportion of total cells in prenatally CAPs-exposed males and females, with no overall change in total CC cellularity. The overall number of Olig2+ lineage cells in the CC was not affected in either sex at the same postnatal timepoint. Assessment of myelin status at early brain maturity (PNDs 57–61) revealed persistent hypermyelination in CAPs-exposed animals of both sexes. In addition, ventriculomegaly was persistent in CAPs-treated females, with possible amelioration of ventriculomegaly in CAPs-exposed males. When oligodendrocyte precursor cell (OPC) pool status was analyzed at PNDs 57–61, there were significant CAPs-induced alterations in cycling Ki67+/Olig2+ cell number and proportion of total cells in the female CC. Total CC cellularity was slightly elevated in CAPs-exposed males at PNDs 57–61. Overall, these data support a growing body of evidence that demonstrate the vulnerability of the developing brain to environmental insults such as ambient particulate matter. The sensitivity of oligodendrocytes and myelin, in particular, to such an insult warrants further investigation into the mechanistic underpinnings of OPC and myelin disruption by constituent air pollutants.

Coping with gravity: the foliar water relations of giant sequoia.

In tall trees, the mechanisms by which foliage maintains sufficient turgor pressure and water content against height-related constraints remain poorly understood. Pressure-volume curves generated from leafy shoots collected crown-wide from 12 large Sequoiadendron giganteum (Lindley) J. Buchholz (giant sequoia) trees provided mechanistic insights into how the components of water potential vary with height in tree and over time. The turgor loss point (TLP) decreased with height at a rate indistinguishable from the gravitational potential gradient and was controlled by changes in tissue osmotica. For all measured shoots, total relative water content at the TLP remained above 75%. This high value has been suggested to help leaves avoid precipitous declines in leaf-level physiological function, and in giant sequoia was controlled by both tissue elasticity and the balance of water between apoplasm and symplasm. Hydraulic capacitance decreased only slightly with height, but importantly this parameter was nearly double in value to that reported for other tree species. Total water storage capacity also decreased with height, but this trend essentially disappeared when considering only water available within the typical range of water potentials experienced by giant sequoia. From summer to fall measurement periods we did not observe osmotic adjustment that would depress the TLP. Instead we observed a proportional shift of water into less mobile apoplastic compartments leading to a reduction in hydraulic capacitance. This collection of foliar traits allows giant sequoia to routinely, but safely, operate close to its TLP, and suggests that gravity plays a major role in the water relations of Earth's largest tree species.

Exploring the Mechanisms Underlying Exercise-Induced Changes in Natural Killer Cell Cytotoxicity

Natural Killer (NK) cells are cytotoxic effectors of the innate immune system that eliminate tumor cells. We have previously shown that NK cell cytotoxicity (NKCA) is enhanced by acute bouts of exercise. However, the mechanisms underlying exercise-induced changes in NKCA are not yet fully understood. Exercise-induced mobilization of highly cytotoxic NK cell subsets has been proposed as one mechanism. Alternatively, exercise increases glucocorticoid and cytokines levels, which have also been shown to alter NKCA. PURPOSE: To examine the role of shifts in proportions of NK cell subsets, cytokines, and hormones on exercise induced changes in NKCA. METHODS: Adults (n=13) cycled 30 min at 115% of their lactate threshold power. Blood was collected pre, post, and 1h post exercise. Effector cells isolated from blood were incubated with K562 or U266 tumor target cells in the presence of autologous serum. NKCA was assessed after 4h by measuring lysed target cells in a flow cytometry based assay. To investigate the effects of factors (hormones and cytokines) released during exercise, pre exercise effectors were incubated with targets in the presence of pre, post, and 1h post exercise serum. The effect of shifts in NK cell subsets was determined by incubating pre, post and 1H post exercise cells with targets in presence of pre exercise serum. We also tested the cytotoxicity of pre, post, and 1h post effectors incubated with serum from the corresponding time point. RESULTS: Autologous pre, post, and 1h post exercise serum did not cause tumor cell lysis in the absence of effectors. The cytotoxicity of pre exercise effector cells was significantly increased against U266 target cells when incubated in 1h post exercise serum (Pre vs. post vs.1H post =0.318±.039 vs. 0.334±.039 vs. 0.438±.039, p<0.05). There was no difference in cytotoxicity of pre, post, 1h post effectors incubated with pre-exercise serum (Pre vs. post vs.1H post =0.321±.046 vs. 0.282±.047 vs. 0.323±.047, p<0.05). CONCLUSION: 1h post exercise serum enhanced resting NK cell cytotoxicity, indicating that factors present in serum after acute exercise can prime effector cell function. Future work will identify levels of glucocorticoids and cytokines present in 1h post exercise serum.

Guided bone regeneration of non-contained mandibular buccal bone defects using deproteinized bovine bone mineral and a collagen membrane: an experimental invivo investigation.

The aim of this pre-clinical invivo study was to analyse different stages of wound healing after guided bone regeneration in non-contained mandibular buccal bone defects. Eighteen female beagle dogs, between 1.5 and 2years old, were used. Buccal bone defects were created in the mandible following extraction of the mesial roots of M1, P4, the distal root of P3 and booth roots of P2. Augmentation procedures of the healed defects were performed 3months later using a bone replacement graft (T1), an absorbable collagen membrane (T2) or a combination of both procedures (T3). Using a randomized block study design, four stages of healing in two groups of dogs were examined (4days, 2, 6weeks and 3months). The animals were euthanized, and biopsies obtained at the end of each of the study periods were prepared for histological examination. The different reconstructive procedures resulted in regenerated tissue compartments of varying size that contained newly formed bone, non-mineralized tissue and bone augmentation biomaterial when a bone replacement graft was used. While the proportions of mineralized tissue increased and non-mineralized tissue decreased over time in the three groups, the changes in proportions of the DBBM material were small. Initial defect depth, healing time and treatment group significantly influenced the percentage of mineralized tissue obtained. The multivariate multilevel analysis showed that significantly larger area proportions of mineralized tissue were obtained when the T2 sites were compared with T1 and T3 sites, what highlights the importance of the barrier membrane effect for attaining new bone formation. Only in the larger size defects (M1) total ROI at T3 and T1 sites was significantly larger than at T2, what highlights the importance of using a bone replacement graft as a space maintenance scaffold. It is suggested that healing following augmentation of non-contained buccal bone defects was characterized by a gradual shift in the relative proportions of non-mineralized and mineralized tissue components.

Systemic Challenges To Global Trade Governance No Way Out?

The short paper sets out to interrogate the major, hydra-headed challenges the world trading order faces from within and without. A good place to begin is with the long list of severe institutional challenges now apparent, which include: institutionalized protectionism sanctioned by WTO rules and the rise of anti-dumping filing by the global South, the decline in the use of the WTO’s dispute resolution, the primary interface between law and governance; the geopolitical shift of titanic proportions from the incipient world ambition of China’s global infrastructural project – The New Silk Road and Belt to remake the world order in its image. If all of the foregoing weren’t enough for a splitting migraine headache, the latest threat comes from the erratic, demagogue Trump, who has told the world media that he is going to ignore any unfavorable ruling by the WTO that stands in the way of making the US ‘great again’. So faced with an impossibly complex list of contentious issues – is there a way forward?

Acoustic emission method to study fracture (Mode-I, II) and residual strength characteristics in composite-to-metal and metal-to-metal adhesively bonded joints

ABSTRACTFailure behaviour of two types of adhesively bonded joints (composite-to-metal, metal-to-metal) has been studied under failure modes (Mode I: double cantilever beam (DCB) and Mode II: three-point end notch flexures (3-ENF)) using acoustic emission (AE) technique. The bonded specimens were prepared using two types of adhesive bond materials with three variations of adhesive bond quality. The effect of the presence of interfacial defects along the interface on the residual strength of the joint has also been studied. It was possible using the maximum AE amplitude method to select the AE events of mechanical significance. However, it proved difficult to propose a definitive AE trait for the mechanical phenomena occurring within specific AE event signals, for all adhesive types, bond qualities, and substrate configurations, therefore, all specimen combinations. There was a notable shift in spectral energy proportion as the AE source of mechanical significance varied along the specimen length for specimen combinations. However, it was difficult to confirm this distinctive trait for all specimen combinations due to difficulty in confirming the location and exact mechanical source. The proposed measurement technique can be useful to assess the overall structural health of a bonded system and may allow identification of defects.