On the origin of optical rotation changes during the κ-carrageenan disorder-to-order transition.

It is well established that solutions of both polymeric and oligomeric κ-carrageenan exhibit a clear change in optical rotation (OR), in concert with gel-formation for polymeric samples, as the solution is cooled in the presence of certain ions. The canonical interpretation - that this OR change reflects a 'coil-to-helix transition' in single chains - has seemed unambiguous; the solution- or 'disordered'-state structure has ubiquitously been assumed to be a 'random coil', and the helical nature of carrageenan in the solid-state was settled in the 1970s. However, recent work has found that κ-carrageenan contains substantial helical secondary structure elements in the disordered-state, raising doubts over the validity of this interpretation. To investigate the origins of the OR, density-functional theory calculations were conducted using atomic models of κ-carrageenan oligomers. Changes were found to occur in the predicted OR owing purely to dimerization of chains, and - together with the additional effects of slight changes in conformation that occur when separated helical chains form double-helices - the predicted OR changes are qualitatively consistent with experimental results. These findings contribute to a growing body of evidence that the carrageenan 'disorder-to-order' transition is a cooperative process, and have further implications for the interpretation of OR changes demonstrated by macromolecules in general.

The impact of musculoskeletal ill health on quality of life and function after critical care: a multicentre prospective cohort study.

Physical disability is a common component of post-intensive care syndrome, but the importance of musculoskeletal health in this population is currently unknown. We aimed to determine the musculoskeletal health state of intensive care unit survivors and assess its relationship with health-related quality of life; employment; and psychological and physical function. We conducted a multicentre prospective cohort study of adults admitted to intensive care for > 48 h without musculoskeletal trauma or neurological insult. Patients were followed up 6 months after admission where musculoskeletal health state was measured using the validated Musculoskeletal Health Questionnaire score. Of the 254 participants, 150 (59%) had a musculoskeletal problem and only 60 (24%) had received physiotherapy after discharge. Functional Comorbidity Index, Clinical Frailty Scale, duration of intensive care unit stay and prone positioning were all independently associated with worse musculoskeletal health. Musculoskeletal health state moderately correlated with quality of life, rs = 0.499 (95%CI 0.392-0.589); anxiety, rs = -0.433 (95%CI -0.538 to -0.315); and depression, rs = -0.537 (95%CI -0.631 to -0.434) (all p < 0.001). Patients with a musculoskeletal problem were less physically active than those without a problem (median (IQR [range]) number of 30 min physical activity sessions per week 1 (0-3.25 [0-7]) vs. 4 (1-7 [0-7]), p < 0.001, respectively). This study found that musculoskeletal health problems were common after intensive care unit stay. However, we observed that < 25% of patients received physical rehabilitation after discharge home. Our work has identified potential high-risk groups to target in future interventional studies.

Root reinforcement and extracellular products reduce streambank fluvial erosion.

A detailed understanding of the factors that impact bank erodibility is necessary to effectively model changes in channel form. This study evaluated the combined contributions of roots and soil microorganisms to soil resistance against fluvial erosion. To do this, three flume walls were constructed to simulate unvegetated and rooted streambanks. Unamended and organic material (OM) amended soil treatments with either no-roots (bare soil), synthetic (inert) roots, or living roots (Panicum virgatum) were created and tested with the corresponding flume wall treatment. OM stimulated the production of extracellular polymeric substances (EPS) and appeared to increase the applied stress required to initiate soil erosion. Synthetic fibers alone provided a base reduction in soil erosion, regardless of the flow rate used. When used in combination, synthetic roots and OM-amendments reduced erosion rates by 86 % or more compared to bare soil; this reduction was identical to the live rooted treatments (95 % to 100 %). In summary, a synergistic relationship between roots and organic carbon inputs can significantly reduce soil erosion rates due to fiber reinforcement and EPS production. These results indicate that root-biochemical interactions, like root physical mechanisms, play an important role in influencing channel migration rates due to reductions in streambank erodibility.

Molecular dynamics simulations and X-ray scattering show the κ-carrageenan disorder-to-order transition to be the formation of double-helices.

Recent molecular dynamics simulations, verified experimentally by solution-state x-ray scattering experiments, have found that κ-carrageenan chains contain helical secondary structure, akin to that found in the solid-state, even in aqueous solution. Furthermore, upon the addition of ions to single chains the simulations found no evidence that any conformational transitions take place. These findings challenge the long-held assumption that the so-called disorder-to-order transition in carrageenan systems involves a uni-molecular 'coil-to-helix transition'. Herein, the results of further molecular dynamics simulations undertaken using pairs of κ-carrageenan chains in 0.1 M NaI solutions are reported, and are validated experimentally using state-of-the-art solution-state WAXS experiments. From initially separated chains double-helices are shown to form, leading the authors to propose 'two single helices-to-stabilized double-helix' as a description of the molecular events taking place during the disorder-to-order transition.

X-ray scattering and molecular dynamics simulations reveal the secondary structure of κ-carrageenan in the solution state.

The solution state structure of κ-carrageenan is typically described as a 'random coil', to indicate a lack of defined secondary structure elements. From this starting point the assignment of an optical-rotation-detected change that follows the introduction of particular ions to such solutions as a 'coil-to-helix transition' seems unambiguous, and thus the canonical description of this important biopolymer's gelling behaviour was born. However, the notion that κ-carrageenan exists in solution as a random coil, devoid of secondary structure, has been questioned a number of times previously in the literature, particularly by the molecular modelling and NMR communities. Regrettably, there has been little desire to-date to address these largely overlooked studies or consider their implications for the nature of the so-called 'coil-to-helix transition'. Despite evidence to the contrary, the random-coil-paradigm has prevailed. Here, new data from synchrotron-enabled solution-state x-ray scattering experiments, combined with state-of-the-art atomistic molecular dynamics simulations, are used to show that the solution-state structure of κ-carrageenan in fact retains many of the helical motifs present in the solid-state, as inferred from fibre diffraction data. Furthermore, no evidence is found to suggest that single chains undergo any uni-molecular conformational transition upon the addition of ions. These findings once again challenge the paradigm that κ-carrageenan exists as a 'random coil' in the solution state, and thereby question the long held assumption that a uni-molecular 'coil-to-helix transition' precedes the dimerization of helices.

The management and outcome of large volume liposarcomas encasing the sciatic nerve.

This paper outlines the oncological outcomes of patients with large volume liposarcomas of the posterior thigh who underwent nerve-preserving surgery utilising epineural dissection. Thirty-seven consecutive patients (group I) with a mean age of 66.2 (31-96) were surgically treated with a planned marginal resection and epineurectomy for liposarcoma with known sciatic nerve involvement between March 1997 and January 2015. The mean follow-up was 79 months (15-192). All patients underwent multidisciplinary team (MDT) pre-operative assessment and staging, with follow-up in Sarcoma Clinic. Pre-operative function was assessed by applying the Toronto extremity salvage score (TESS). Oncological and functional outcomes were recorded. In grades 1, 2, and 3, 24, 6, and 7 liposarcomas, respectively, were included with mean volume 1859 cm3. Sciatic nerve involvement extended for 13-30 cm; in one case, the nerve was abutting the tumour throughout its length. Soft tissue reconstructive surgery was required in three cases. The remainder underwent direct primary closure. Seventeen patients underwent post-operative adjuvant radiotherapy 46-60 Gy and three received chemotherapy. There was local recurrence of disease in three patients. One patient had post-radiation wound breakdown treated non-operatively. Three patients died of an unrelated cause. When compared to a cohort of 37 patients without sciatic nerve involvement (group II), there were no significant differences in local and systemic recurrence rate or post-operative survival. In conclusion, sciatic nerve-preserving surgery is both possible and safe when using a planned epineural dissection in large volume tumours encasing the sciatic nerve.

Meta-regression Analysis of Study Heterogeneity for Systemic Outcomes after Periodontal Therapy.

INTRODUCTION: The contribution of periodontal disease to adverse systemic consequences remains controversial. This analysis examined 2 well-investigated conditions independently and combined-adverse pregnancy outcomes and glycemic control for patients with diabetes-based on shared pathogenic mechanisms of periodontal infection and inflammation. It was proposed that inconsistencies in study design significantly contribute to outcome discrepancies found between periodontal intervention studies undergoing meta-analysis. METHODS: Meta-analyses evaluating periodontal interventions on the rate of preterm birth and changes in glycated hemoglobin A1c in type 2 diabetes populations were conducted based on a systematic review of randomized controlled trials. Meta-regression covariates for exploring heterogeneity included sample size, level of medical management, and bias risk as moderator variables in a random-effects meta-regression. RESULTS: Systematic review identified 17 studies of diabetes and 13 of pregnancy outcomes. Analyses of these studies identified 0.50% reduction in HbA1c and 0.78 odds ratio for preterm births. The heterogeneity associated with the models was high (I2 = 92.4 and I2 = 62.7%, respectively). The adjusted models evaluating each systemic condition separately accounted for 52.2% of the effect for diabetes and 81.4% for pregnancy outcome effects independently, and 63.5% collectively, across interventional studies. CONCLUSION: This systematic review with meta-regression analysis of heterogeneity demonstrates that disparate results seen in randomized controlled trials of periodontal therapy affecting systemic outcomes may be explained in large part by study design, specifically stringency in consideration of medical management and sample size. The potential for confounding factors to influence outcomes remains a concern in understanding the implications of oral health on systemic conditions. KNOWLEDGE TRANSFER STATEMENT: The findings of this study demonstrate that much of the benefits seen from periodontal therapy on adverse systemic outcomes for diabetes and pregnancy are due to limitations in study design.

Head and neck sarcoma: three-year data from a tertiary referral centre.

INTRODUCTION: Sarcomas of the head and neck are neoplasms arising from the embryonic mesenchyme. They are rare and heterogeneous in nature and are associated with significant morbidity and mortality. This study evaluates patients referred to the Oxford Sarcoma Service, a tertiary referral centre. METHODS: Patients discussed over a three-year period were included. Medical records were analysed using the electronic patient record database. Data were acquired on a range of domains, including: demographics, histopathology, treatment modality, recurrence, mortality, survival, etc. RESULTS: Thirty-two eligible patients, 21 male and 11 female, were identified with a mean age of 58 years; 26 out of 32 patients had high-grade sarcomas. The commonest histological subtype was chondrosarcoma (8/32). Twenty-two underwent planned multidisciplinary team surgical resection after biopsy and staging: negative margins were noted in 9, with close and involved margins in 5 and 8, respectively. Local recurrence was noted in 13 and 6 had metastatic disease out of the 32 eligible patients. Mortality was noted in 10 out of 32 patients. Mean survival was 69.5 months. Five-year overall survival was 64%. Surgery demonstrated statistically significant improvement in survival (p=0.0095). There were no significant differences in survival, recurrence or marginal status between methods of adjuvant or neoadjuvant therapy. CONCLUSION: Outcomes of head and neck sarcomas are inferior compared with other types of sarcoma. The nature of the complex surrounding anatomy presents unique challenges in surgical management. This in turn affects rates of local recurrence and prognosis. Therefore, it is critical that they are managed in tertiary, specialist centres with a multidisciplinary approach.

Anomalous diffusion driven by the redistribution of internal stresses.

This article explores the mathematical description of anomalous diffusion, driven not by thermal fluctuations but by internal stresses. A continuous time random walk framework is outlined in which the waiting times between displacements (jumps), generated by the dynamics of internal stresses, are described by the generalized Γ distribution. The associated generalized diffusion equation is then identified. The solution to this equation is obtained as an integral over an infinite series of Fox H functions. The probability density function is identified as initially non-Gaussian, while at longer timescales Gaussianity is recovered. Likewise, the second moment displays a transient nature, shifting between subdiffusive and diffusive character. The potential application of this mathematical description to the quaking observed in several soft-matter systems is discussed briefly.

Quantitative characterisation of ballistic cartridge cases from micro-CT.

Evaluation of cartridge cases is essential within forensic ballistic analysis and is used in an attempt to establish a connection to the weapon used to fire it. This study consists of two experiments. The aims of Experiment 1 were to establish whether micro-CT is appropriate and repeatable for ballistic cartridge case analysis and if measurements can be extracted repeatably and reliably. Experiment 2 aimed to compare cartridge cases from two weapons to establish the magnitude of variation within and between weapons. A total of 48 cartridge cases fired by two distinct weapons were collected and micro-CT scanned to a high resolution. One randomly selected cartridge was scanned ten times under the same conditions to ensure repeatability of the scanning conditions in Experiment 1. Three novel measurements to quantitatively assess the firing pin impressions were proposed in Experiment 1 and comparatively analysed from two weapons in Experiment 2. Experiment 1 showed that micro-CT is an effective and highly repeatable and reliable method for 3-dimensional imaging and measurement of ballistic cartridge cases. Furthermore, high agreement for inter-rater reliability was found between five raters. Quantitative micro-CT analysis of the firing pin impression measurements in Experiment 2 showed a significant difference between the two studied weapons using Welch's t-test (p < 0.01). This study shows the advantage and reliability of utilising micro-CT for firing pin impression analysis. Quantitation of the firing pin impression allows distinction between the weapons studied. With expansion to further weapons, application of this methodology could complement current analysis techniques through classification models.

A comparative study of tough hydrogen bonding dissipating hydrogels made with different network structures.

Hydrogels are excellent soft materials to interface with biological systems. Precise control and tunability of dissipative properties of gels are particularly interesting in tissue engineering applications. In this work, we produced hydrogels with tunable dissipative properties by photopolymerizing a second polymer within a preformed cross-linked hydrogel network of poly(acrylamide). We explored second networks made with different structures and capacity to hydrogen bond with the first network, namely linear poly(acrylic acid) and branched poly(tannic acid). Gels incorporating a second network made with poly(tannic acid) exhibited excellent stiffness (0.35 ± 0.035 MPa) and toughness (1.64 ± 0.26 MJ m-3) compared to the poly(acrylic acid) counterparts. We also demonstrate a strategy to fabricate hydrogels where the dissipation (loss modulus) can be tuned independently from the elasticity (storage modulus) suitable for cell culture applications. We anticipate that this modular design approach for producing hydrogels will have applications in tailored substrates for cell culture studies and in load bearing tissue engineering applications.

Producing three-dimensional printed models of the hepatobiliary system from computed tomography imaging data.

INTRODUCTION: Macroscopic anatomy has traditionally been taught using cadaveric material, lectures and a variety of additional resources including online modules and anatomical models. Traditional plastic models are effective educational tools yet they have significant drawbacks such as a lack of anatomical detail, a lack of texturisation and cost. Three-dimensional printed models stand to solve these problems and widen access to high-quality anatomical teaching. This paper outlines the use of three-dimensional multiplanar imaging (computed tomography) in the development of an accurate model of the hepatobiliary system. MATERIALS AND METHODS: Computed tomography scans were used to construct a virtual three-dimensional model of the hepatobiliary system. This was printed locally as a full-size colour model. We give a complete account of the process and software used. DISCUSSION: This study is among the first of a series in which we will document the newly formed Oxford Library of Anatomy. This series will provide the methodology for the production of three-dimensional models from computed tomography and magnetic resonance imaging scans, and the library will provide a complete collection of the most complex anatomical areas. We hope that these models will form an important adjunct in teaching anatomy to medical students and surgical trainees.

Accurate prediction of saw blade thicknesses from false start measurements.

BACKGROUND: False start analysis is the examination of incomplete saw marks created on bone in an effort to establish information on the saw that created them. The present study aims to use quantitative data from micro-CT cross-sections to predict the thickness of the saw blade used to create the mark. Random forest statistical models are utilised for prediction to present a methodology that is useful to both forensic researchers and practitioners. METHOD: 340 false starts were created on 32 fleshed cadaveric leg bones by 38 saws of various classes. False starts were micro-CT scanned and seven measurements taken digitally. A regression random forest model was produced from the measurement data of all saws to predict the saw blade thickness from false starts with an unknown class. A further model was created, consisting of three random forests, to predict the saw blade thickness when the class of the saw is known. The predictive capability of the models was tested using a second sample of data, consisting of measurements taken from a further 17 false starts created randomly selected saws from the 38 in the experiment. RESULTS: Random forest models were able to accurately predict up to 100% of saw blade thicknesses for both samples of false starts. CONCLUSION: This study demonstrates the applicability of random forest statistical regression models for reliable prediction of saw blade thicknesses from false start data. The methodology proposed enables prediction of saw blade thickness from empirical data and offers a significant step towards reduced subjectivity and database formation in false start analysis. Application of this methodology to false start analysis, with a more complete database, will allow complementary results to current analysis techniques to provide more information on the saw used in dismemberment casework.

Chronic HPA activity in mothers with preterm delivery: A pilot nested case-control study.

BACKGROUND: Chronic hypothalamic-pituitary-adrenal (HPA) axis activity role in the pathogenesis of preterm birth (PTB) remains unclear due to inconsistent measures with limited ability to monitor long-term cortisol concentrations. We explored this relationship using the novel method of assessing cortisol in hair, which is a valid and reliable measure of chronic HPA axis activity. METHODS: 137 participants (40 PTB cases and 97 controls from a birth cohort of pregnant women in Peru) were interviewed and invited to provide a 9-cm hair sample from the posterior vertex position of the scalp (mean = 13 weeks gestation). Hair cortisol concentration (HCC) was determined using luminescence immunoassay and values were natural-log transformed. PTB cases were defined as women who delivered before 37 gestational weeks. Case-control differences were assessed using multivariable linear and logistic regressions. RESULTS: Overall, combined pre-conception and first-trimester HCC was 13% lower among cases as compared with controls (p-value = 0.01). Compared with controls, maternal HCC among PTB cases were 14% (p = 0.11), 10% (p = 0.22) and 14% (p = 0.08) lower for 3-6 months pre-conception, 0-3 months pre-conception, and first trimester, respectively. After adjusting for putative confounders, a 1-unit increase in HCC was associated with 55% reduced odds of PTB (aOR = 0.45; 95% CI: 0.17-1.17). For a 1-unit increase in HCC in the scalp-intermediate and scalp-distal segments (representing HCC concentrations in 0-3 months pre-conception and first trimester), the corresponding odds for PTB were 0.53 (95% CI: 0.19-1.48) and 0.39 (95% CI: 0.13-1.13), respectively. CONCLUSIONS: Women who deliver preterm, as compared with those who deliver at term, have lower preconception and first trimester HCC. Our findings suggest that HPA axis activation, integral to the adaptive stress-response system, may be chronically dysregulated in women at increased risk of PTB.

Social contributors to cardiometabolic diseases in indigenous populations: an international Delphi study.

OBJECTIVE: The objective of this study was to identify priority social factors contributing to indigenous cardiometabolic diseases. STUDY DESIGN: A three-round Delphi process was used to consolidate and compare the opinions of 60 experts in indigenous cardiometabolic health from Australia, New Zealand and the United States. METHODS: Round one: three open-ended questions: (i) historical, (ii) economic and (iii) sociocultural factor contributors to cardiometabolic disease risk. Round two: a structured questionnaire based on the results from the first round; items were ranked according to perceived importance. Final round: the items were reranked after receiving the summary feedback. RESULTS: Several key findings were identified: (i) an important historical factor is marginalisation and disempowerment; (ii) in terms of economic and sociocultural factors, the panellists came to the consensus that the socio-economic status and educational inequalities are important; and (iii) while consensus was not reached, economic and educational factors were also perceived to be historically influential. CONCLUSION: These findings support the need for multilevel health promotion policy. For example, tackling financial barriers that limit the access to health-promoting resources, combined with improving literacy skills to permit understanding of health education.

Epidemiology of Adult Uveitis in a Northern Ireland Tertiary Referral Centre.

Uveitis is inflammation of the middle layer of the eye, called the uveal tract. It can be classified by anatomic location of the focus of inflammation inside the eye: intermediate, posterior or pan-uveitis. These types are less common than anterior uveitis (iritis), but more often have underlying aetiologies that require identification. Some aetiologies are infective, while others require systemic immunosuppression. Underlying aetiologies vary in different regions in the world, and so local data is important to guide clinicians. This study describes the aetiology of 255 cases of intermediate, posterior and pan-uveitis in adults. The most common non-infectious causes, after idiopathic, were sarcoid, Birdshot chorioretinopathy, demyelination-related and Behçet's, whereas toxoplasmosis and herpes simplex and zoster related retinitis were the common infectious causes. Neither age nor sex of the patient were related to aetiology.

Effectiveness of scoliosis-specific exercises for adolescent idiopathic scoliosis compared with other non-surgical interventions: a systematic review and meta-analysis.

STUDY DESIGN: Systematic review and meta-analysis. OBJECTIVE: To assess the effectiveness of scoliosis-specific exercises (SSE) on adolescent idiopathic scoliosis (AIS) compared with other non-surgical interventions. BACKGROUND: AIS is a complex deformity of the spine that develops between the age of 10years and skeletal maturity. SSE are prescribed to patients to reduce or slow curve progression, although their effectiveness is unknown. METHODS: Electronic databases were searched for relevant studies. Randomised controlled trials were eligible if they compared SSE with non-surgical interventions for individuals with AIS. Three authors independently extracted data, evaluated methodological quality and assessed the quality of evidence. Meta-analysis was performed where possible; otherwise, descriptive syntheses are reported. RESULTS: Nine randomised controlled trials were included. Four had a high risk of bias, three had an unclear risk and two had a low risk. Very-low-quality evidence indicated that SSE improved some measures of spinal deformity, function, pain and overall health-related quality of life (HRQoL). Very-low-quality evidence suggested that SSE had no effect on self-image and mental health. Very-low-quality evidence showed that bracing was more effective than SSE on measures of spinal deformity. However, SSE showed greater improvements in function, HRQoL, self-image, mental health and patient satisfaction with treatment. No differences were found for pain or trunk rotation. CONCLUSIONS: SSE may be effective for improving measures of spinal deformity for people with AIS, but the evidence is of very low quality. Future studies should evaluate relevant clinical measures and cost-effectiveness using rigorous methods and reporting standards.

Prediction and Visualisation of Bony Impingement for Subject Specific Total Hip Arthroplasty.

Bony impingement (BI) may contribute to restricted hip joint motion, and recurrent dislocation after total hip arthroplasty (THA), and therefore, should be avoided where possible. However, BI risk assessment is generally performed intra-operatively by surgeons, which is partially subjective and qualitative. Therefore, the aim of the study was to develop a method for identifying subject-specific BI, and subsequently, visualising BI area on native bone anatomy to highlight the amount of bone should be resected. Activity definitions and subject-specific bone geometries, constructed from CT scans, with planned implants were used as inputs for the method. For each activity, a conical clearance angle (CCA) was checked between femur and pelvis through simulation. Simultaneously, BI boundary and area were automatically calculated using ray intersection and region growing algorithm respectively. The potential use of the developed method was explained through a case study using an anonymised pre-THA patient data. Two pure (flexion, and extension) and two combined hip joint motions (internal and external rotation at flexion and extension respectively) were considered as activities. BI area were represented in two ways: (a) CCA specific where BI area for each activity with different CCAs was highlighted, (b) activity specific where BI area for all activities with a particular CCA was presented. Result showed that BI area between the femoral and pelvic parts was clearly identified so that the pre-operative surgical plan could be adjusted to minimise impingement. Therefore, this method could potentially be used to examine the effect of different preoperative plans and hip motion on BI, and to guide bony resection during THA surgery.

Metabolomics signatures associated with an oral glucose challenge in pregnant women.

AIM: The oral glucose tolerance test (OGTT), widely used as a gold standard for gestational diabetes mellitus (GDM) diagnosis, provides a broad view of glucose pathophysiology in response to a glucose challenge. We conducted the present study to evaluate metabolite changes before and after an oral glucose challenge in pregnancy; and to examine the extent to which metabolites may serve to predict GDM diagnosis in pregnant women. METHODS: Peruvian pregnant women (n=100) attending prenatal clinics (mean gestation 25 weeks) participated in the study with 23% of them having GDM diagnosis. Serum samples were collected immediately prior to and 2-hours after administration of a 75-g OGTT. Targeted metabolic profiling was performed using a LC-MS based metabolomics platform. Changes in metabolite levels were evaluated using paired Student's t-tests and the change patterns were examined at the level of pathways. Multivariate regression procedures were used to examine metabolite pairwise differences associated with subsequent GDM diagnosis. RESULTS: Of the 306 metabolites detected, the relative concentration of 127 metabolites were statistically significantly increased or decreased 2-hours after the oral glucose load (false discovery rate [FDR] corrected P-value<0.001). We identified relative decreases in metabolites in acylcarnitines, fatty acids, and diacylglycerols while relative increases were noted among bile acids. In addition, we found that C58:10 triacylglycerol (ß=-0.08, SE=0.04), C58:9 triacylglycerol (ß=-0.07, SE=0.03), adenosine (ß=0.70, SE=0.32), methionine sulfoxide (ß=0.36, SE=0.13) were significantly associated with GDM diagnosis even after adjusting for age and body mass index. CONCLUSIONS: We identified alterations in maternal serum metabolites, representing distinct cellular and metabolic pathways including fatty acid metabolism, in response to an oral glucose challenge. These findings offer novel perspectives on the pathophysiological mechanisms underlying GDM.

Micro-CT for saw mark analysis on human bone.

In toolmark analysis, microscopy techniques, such as micro-CT, are used to visualise and measure toolmarks left on bones by a tool. In dismemberment cases, properties such as the width of the saw mark can provide cues to which tool was used by the culprit. The aim of the current study was to establish whether; (i) micro-CT is an appropriate imaging technique for saw mark analysis, (ii) toolmarks statistically differ when created with different tools, (iii) toolmark width can predict tool blade width, and (iv) toolmarks differ if created under different methodological conditions. Across two experiments, 270 saw marks were created using eight tools with either a controlled or free saw action on either fleshed or defleshed human long bone. Toolmarks were micro-CT scanned and seven toolmark properties were categorised or measured by two independent raters. The current study found that; (i) micro-CT was found to be a powerful and reliable imaging method for the visualisation and measurement of saw mark properties, (ii) toolmark properties differed significantly within and between various methodological conditions (p<.001) when created by eight different tools, (iii) a regression model developed using toolmark widths from Experiment 2 overall predicted 94% of tool widths in Experiment 1, and iv) methodological factors such as tissue presence and saw action significantly and inconsistently influenced toolmark properties for different tools. The study further validates the use of mirco-CT for saw mark analysis and demonstrates the potential of using toolmark properties to determine the tool used in cases of dismemberment. Given the effects that methodological factors such as tissue presence can have on toolmark properties, future studies should use experimental set ups with fleshed human tissue and use a free saw action.