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The Remote Assessment of Disease and Relapse – Alzheimer's Disease (RADAR-AD) consortium evaluated remote measurement technologies (RMTs) for assessing functional status in AD. The consortium engaged with the European Medicines Agency (EMA) to obtain feedback on identification of meaningful functional domains, selection of RMTs and clinical study design to assess the feasibility of using RMTs in AD clinical studies. We summarized the feedback and the lessons learned to guide future projects. [ABSTRACT FROM AUTHOR]

Advances in science, medicine and engineering rely on breakthroughs in imaging, particularly for obtaining multiscale, three-dimensional information from functional systems such as integrated circuits or mammalian brains. Achieving this goal often requires combining electron- and photon-based approaches. Whereas electron microscopy provides nanometre resolution through serial, destructive imaging of surface layers1, ptychographic X-ray computed tomography2 offers non-destructive imaging and has recently achieved resolutions down to seven nanometres for a small volume3. Here we implement burst ptychography, which overcomes experimental instabilities and enables much higher performance, with 4-nanometre resolution at a 170-times faster acquisition rate, namely, 14,000 resolution elements per second. Another key innovation is tomographic back-propagation reconstruction4, allowing us to image samples up to ten times larger than the conventional depth of field. By combining the two innovations, we successfully imaged a state-of-the-art (seven-nanometre node) commercial integrated circuit, featuring nanostructures made of low- and high-density materials such as silicon and metals, which offer good radiation stability and contrast at the selected X-ray wavelength. These capabilities enabled a detailed study of the chip’s design and manufacturing, down to the level of individual transistors. We anticipate that the combination of nanometre resolution and higher X-ray flux at next-generation X-ray sources will have a revolutionary impact in fields ranging from electronics to electrochemistry and neuroscience.X-ray computed tomography is combined with burst ptychography and filtered back-propagation to achieve high-speed, three-dimensional imaging of features as small as 4 nm. [ABSTRACT FROM AUTHOR]

Structural colors arise from selective light interaction with (nano)structures, which give them advantages over pigmented colors such as resistance to fading and possibility to be fabricated out of traditional low-cost and non-toxic materials. Since the color arises from the photonic (nano)structures, different structural features can impact their photonic response and thus, their color. Therefore, the detailed characterization of their structural features is crucial for further improvement of structural colors. In this work, we present a detailed multi-scale structural characterization of ceramic-based photonic glasses by using a combination of high-resolution ptychographic X-ray computed tomography and small angle X-ray scattering. Our results uncover the structure-processing-properties' relationships of such nanoparticles-based photonic glasses and point out to the need of a review of the structural features used in simulation models concomitantly with the need for further investigations by experimentalists, where we point out exactly which structural features need to be improved. [ABSTRACT FROM AUTHOR]

Background: Among the most recent methods to diagnose liver fibrosis is 2D shear wave elastography (2D-SWE). However, the evidence in the Latin population is limited, and there is no consensus on the cutoff points for each stage of fibrosis. Aim: To evaluate the diagnostic performance of 2D-SWE for liver fibrosis in adults with obesity who underwent bariatric surgery (BS). Methods: We conducted a cross-sectional study on patients with obesity who underwent BS between 2020 and 2021. Liver stiffness measurement was reported as the mean of valid measurements in kilopascals made with the 2D-SWE. The outcome was biopsy-proven liver fibrosis. ROC curves were constructed for significant fibrosis (F≥2) and advanced fibrosis (F≥3), with their respective area under the curve (AUC). To obtain the best cutoff point for each scenario, we used the Youden index. The 95% confidence intervals (95% CI) for each cutoff point were estimated by bootstrap with 1000 replications. Results: We analyzed data from 227 patients. The mean age was 37.8 ± 11.1 years and 65.2% were women. Overall, the AUC for significant and advanced fibrosis was 0.54 (95% CI: 0.47–0.62) and 0.73 (95% CI: 0.60–0.87), respectively. For advanced fibrosis, higher AUCs were found among women (AUC: 0.82; 95% CI: 0.59–1.00) and among patients with morbid obesity (AUC: 0.78; 95% CI: 0.61–0.99). Conclusion: The 2D-SWE appears to be a valuable tool for screening advanced liver fibrosis in candidates for BS, mainly in the female population and in adults with morbid obesity. [ABSTRACT FROM AUTHOR]

Despite a century of research, our understanding of cement dissolution and precipitation processes at early ages is very limited. This is due to the lack of methods that can image these processes with enough spatial resolution, contrast and field of view. Here, we adapt near-field ptychographic nanotomography to in situ visualise the hydration of commercial Portland cement in a record-thick capillary. At 19 h, porous C-S-H gel shell, thickness of 500 nm, covers every alite grain enclosing a water gap. The spatial dissolution rate of small alite grains in the acceleration period, ∼100 nm/h, is approximately four times faster than that of large alite grains in the deceleration stage, ∼25 nm/h. Etch-pit development has also been mapped out. This work is complemented by laboratory and synchrotron microtomographies, allowing to measure the particle size distributions with time. 4D nanoimaging will allow mechanistically study dissolution-precipitation processes including the roles of accelerators and superplasticizers. In this work, the authors use near-field ptychographic nanotomography to visualize cement hydration in situ. They report hydration features with submicrometer detail including calcium silicate dissolution rates, etch-pit growth rates and water-to-air porosity evolution. [ABSTRACT FROM AUTHOR]

Palmar fibromatosis, also known as Dupuytren's disease (DD), is a common and heritable fibrosis of the hand. It is characterized by the formation of myofibroblastic nodules that can progress to palmar-digital contractures and permanent loss of dexterity. The presence of inflammatory cell infiltrate within these nodules has been interpreted to suggest a pathogenesis mediated by a proinflammatory microenvironment. However, the molecular mechanisms driving the formation of pro-fibrotic microenvironments in this and other fibroses remain unclear. To gain insights into this process, we have assessed the contributions of an alternatively spliced, multi-functional transcription factor, Wilms Tumor 1 (WT1), previously shown to be upregulated in primary myofibroblasts derived from DD tissues. Proinflammatory cytokine stimuli of DD myofibroblasts enhanced the expression of several distinct WT1 variants, the most sustained being a 5′ truncated version of WT1, alternative WT1 (AWT1). Constitutive adenoviral expression of AWT1 in myofibroblasts derived from phenotypically non-fibrotic palmar fascia significantly induced the expression and secretion of proinflammatory cytokines, including some with potential as novel therapeutic targets. In summary, these data implicate roles for sustained AWT1 expression in DD as a transcriptional driver of a proinflammatory fascial milieu. [ABSTRACT FROM AUTHOR]

Collagen bundle orientation (CBO) in myocardial infarct scars plays a major role in scar mechanics and complications after infarction. We aim to compare four histopathological methods for CBO measurement in myocardial scarring. Myocardial infarction was induced in 21 pigs by balloon coronary occlusion. Scar samples were obtained at 4 weeks, stained with Masson's trichrome, Picrosirius red, and Hematoxylin–Eosin (H&E), and photographed using light, polarized light microscopy, and confocal microscopy, respectively. Masson's trichrome images were also optimized to remove non-collagenous structures. Two observers measured CBO by means of a semi-automated, Fourier analysis protocol. Interrater reliability and comparability between techniques were studied by the intraclass correlation coefficient (ICC) and Bland–Altman (B&A) plots and limits of agreement. Fourier analysis showed an almost perfect interrater reliability for each technique (ICC ≥ 0.95, p < 0.001 in all cases). CBO showed more randomly oriented values in Masson's trichrome and worse comparability with other techniques (ICC vs. Picrosirius red: 0.79 [0.47–0.91], p = 0.001; vs. H&E-confocal: 0.70 [0.26–0.88], p = 0.005). However, optimized Masson's trichrome showed almost perfect agreement with Picrosirius red (ICC 0.84 [0.6–0.94], p < 0.001) and H&E-confocal (ICC 0.81 [0.54–0.92], p < 0.001), as well as these latter techniques between each other (ICC 0.84 [0.60–0.93], p < 0.001). In summary, a semi-automated, Fourier-based method can provide highly reproducible CBO measurements in four different histopathological techniques. Masson's trichrome tends to provide more randomly oriented CBO index values, probably due to non-specific visualization of non-collagenous structures. However, optimization of Masson's trichrome microphotographs to remove non-collagenous components provides an almost perfect comparability between this technique, Picrosirius red and H&E-confocal. [ABSTRACT FROM AUTHOR]

Chirality is a structural property of molecules lacking mirror symmetry that has strong implications in diverse fields, ranging from life sciences to materials science. Chirality-sensitive spectroscopic methods, such as circular dichroism, exhibit weak signal contributions on an achiral background. Helical dichroism, which is based on the orbital angular momentum (OAM) of light, offers a new approach to probe molecular chirality, but it has never been demonstrated on disordered samples. Furthermore, in the optical domain the challenge lies in the need to transfer the OAM of the photon to an electron that is localized on an ångström-size orbital. Here we overcome this challenge using hard X-rays with spiral Fresnel zone plates, which can induce an OAM. We present the helical dichroism spectra of a disordered powder sample of enantiopure salts of the molecular complex of [Fe(4,4′-diMebpy)3]2+ at the iron K edge (7.1 keV) with OAM-carrying beams. The asymmetry ratios for the helical dichroism spectra are within one to five percent for OAM beams with topological charges of one and three. These results open a new window into the studies of molecular chirality and its interaction with the OAM of light. Linearly polarized orbital angular momentum-carrying hard X-ray beams are induced using spiral Fresnel zone plates. By sending the hard X-ray beams to disordered enantiopure molecular complexes, the helicity-dependent and chiral-sensitive signal is obtained. [ABSTRACT FROM AUTHOR]

Diffractive and refractive optical elements have become an integral part of most high-resolution X-ray microscopes. However, they suffer from inherent chromatic aberration. This has to date restricted their use to narrow-bandwidth radiation, essentially limiting such high-resolution X-ray microscopes to high-brightness synchrotron sources. Similar to visible light optics, one way to tackle chromatic aberration is by combining a focusing and a defocusing optic with different dispersive powers. Here, we present the first successful experimental realisation of an X-ray achromat, consisting of a focusing diffractive Fresnel zone plate (FZP) and a defocusing refractive lens (RL). Using scanning transmission X-ray microscopy (STXM) and ptychography, we demonstrate sub-micrometre achromatic focusing over a wide energy range without any focal adjustment. This type of X-ray achromat will overcome previous limitations set by the chromatic aberration of diffractive and refractive optics and paves the way for new applications in spectroscopy and microscopy at broadband X-ray tube sources. X-ray diffractive and refractive optical elements suffer from chromatic aberrations, limiting high-resolution X-ray microscopes mainly to bright synchrotron sources. Here, the authors experimentally realise an achromatic X-ray lens by combing a focusing diffractive Fresnel zone plate and a defocusing refractive lens. [ABSTRACT FROM AUTHOR]

Preventive detention legislation allows for the ongoing detention of an offender's sentence. We explore the effects of pretrial detention on case outcomes in Bogotá, Colombia, from 2005–2017. Using pretrial judge leniency as an instrument, we find that pretrial detention leads to a 48 percentage point increase in the likelihood of being convicted. The rise in the probability of reaching agreements among defendants who would have otherwise been acquitted or had their charges dropped explains our findings. We also find evidence of an increase in the likelihood of pleading guilty for those detained pretrial and who experience a more significant incarceration sentence. Colombian prisons are overcrowded. Pretrial detentions add to the cost of maintenance of the prisoners. Policymakers should consider whether the costs associated with pretrial detention outweigh the potential benefits. [ABSTRACT FROM AUTHOR]

Today, various methods such as bioleaching are increasingly used to remove toxic and reuse useful metals from low-grade ores and tailings. Bioleaching is an ecologically based technique carried by iron or sulfur-oxidizing bacteria, which convert insoluble metal sulfide to soluble metal sulfate. The purpose of this study was to test and compare two different methods, including Flask and Column experiments, to remove Zinc, Copper, Arsenic, and Iron. The materials were the same in both tests; inoculum came from the tailings of Neves-Corvo Mine, and the mineral sample was collected from Panasqueira Wolfram-Tin mine. Firstly, the cultures were tested for metal resistance and adapted by 3-day transference, adding sodium thiosulfate as an energy source supplement. Secondly, bioleaching tests were conducted in Flasks and Columns in 35 and 30 days, respectively. Finally, samples were taken to evaluate particle size, chemical compositions, bacterial growth, pH, oxidation–reduction potential (ORP), sulfate concentration, and metal content in the leachate. Besides, the Scanning Electron Microscope (SEM) pictures proved the existence of bacterial cells during the bioleaching tests. The results indicated that the Flask tests were superior to Column experiments in removing Zinc, Arsenic, and Copper from the mineral ore samples. However, Column experiments showed better results in the recovery of Iron in comparison with Flask tests. [ABSTRACT FROM AUTHOR]

Cryptosporidium spp. are apicomplexan protozoa associated with chronic diarrhea in AIDS and other immunocompromised patients, and one of the commonest causes of childhood diarrhea and malnutrition, particularly in low-income settings. In Colombia, there are few molecular epidemiological studies on Cryptosporidium spp.; thereby, the transmission dynamics of this parasite in the country is poorly known. This study evaluated the diversity of Cryptosporidium at species, subtype family, and subtype level in children attending various day-care centers in Medellin, Colombia. Two hundred and ninety stool samples from children < 5 years of age were collected from April to November of 2015. All samples were processed by PCR and sequence analysis of the ssu RNA gene and the gp60 gene. An infection rate of 2.4% was observed, with only two Cryptosporidium species identified: C. hominis (6/7) and C. meleagridis (1/7). Cryptosporidium hominis isolates belonged to the subtypes IbA10G2, IaA13R6 and IaA13R7; IIIbA26G1R1 C. meleagridis subtype was also detected. There is a C. hominis predominance in the children evaluated, suggesting an important role of the anthroponotic transmission cycle in the day-care centers analyzed. Further investigation is required to determine infection sources and susceptible hosts in order to define appropriate management of cryptosporidiosis. [ABSTRACT FROM AUTHOR]

To evaluate the response to hepatitis B virus (HBV) vaccine in patients on biological therapy. Adults with autoimmune inflammatory diseases on biological therapy such as anti-TNFα, rituximab, tocilizumab, abatacept, or anakinra were included. Hepatitis B surface antibody (anti-HBs) was measured by ELISA before and after vaccination. Seroconversion was considered when an anti-HBs titer > 10 mIU/mL was achieved. The effect of treatment on the immunoprotective state was studied. The response was compared with that obtained in patients on synthetic disease modifying anti-rheumatic drugs (DMARDs) and healthy controls. A total of 187 patients on biologicals, 48 on synthetic DMARDs, and 49 on healthy controls were analyzed. More than 80% of patients on biologics responded to the vaccine but required more boosters and second vaccine series. Patients who achieved seroconversion were younger than those who did not (47.10 ± 12.99 vs. 53.18 ± 10.54 years, p = 0.012). Being on etanercept or golimumab was associated with seroconversion, while being on rituximab was not. Seroconversion was achieved in 93.75% of patients on synthetic DMARDs and 97.96% of healthy controls. The seroconversion rate in the biologics group was lower than in the synthetic DMARD group (p = 0.043) and tended to be lower than in the healthy group (p = 0.056). In patients on biological therapy, a high rate of HBV vaccine response can be achieved when a complete vaccination schedule is administered. Vaccination while not on biological agents reduces the requirement for boosters and revaccination. Key points: • Patients on biological therapy can achieve high rates of immune response to HBV vaccine when complete vaccination schedules are administered. • However, to achieve such a high seroconversion rate, more boosters and second vaccination series are required. • This supports the proposal already made to provide HBV vaccination to all patients with an autoimmune inflammatory disease after the diagnosis is made and not when the use of a biological treatment is under consideration. [ABSTRACT FROM AUTHOR]

Delayed enhancement cardiovascular magnetic resonance (MR) is the gold-standard for non-invasive assessment after myocardial infarction (MI). MR microscopy (MRM) provides a level of detail comparable to the macro objective of light microscopy. We used MRM and correlative histopathology to identify infarct and remote tissue in contrast agent-free multi-sequence MRM in swine MI hearts. One control group (n = 3 swine) and two experimental MI groups were formed: 90 min of ischemia followed by 1 week (acute MI = 6 swine) or 1 month (chronic MI = 5 swine) reperfusion. Representative samples of each heart were analysed by contrast agent-free multi-sequence (T1-weighting, T2-weighting, T2*-weighting, T2-mapping, and T2*-mapping). MRM was performed in a 14-Tesla vertical axis imager (Bruker-AVANCE 600 system). Images from MRM and the corresponding histopathological stained samples revealed differences in signal intensities between infarct and remote areas in both MI groups (p-value < 0.001). The multivariable models allowed us to precisely classify regions of interest (acute MI: specificity 92% and sensitivity 80%; chronic MI: specificity 100% and sensitivity 98%). Probabilistic maps based on MRM images clearly delineated the infarcted regions. As a proof of concept, these results illustrate the potential of MRM with correlative histopathology as a platform for exploring novel contrast agent-free MR biomarkers after MI. [ABSTRACT FROM AUTHOR]

Banana (Musa acuminate Colla, cultivar Grand Nain) is the main crop in Canary Islands, covering an area of about 9000 ha with a production in 2017 of 437.782 t of banana worth 104.4 million Euros. Today, one of the most used pest control method is the Integrated Pest Management (IPM), which takes into account the different management options for pest control, giving priority to the least harmful solutions. This research aims to improve the use of IPM to control populations of Chrysodeixis chalcites through understanding growing stage and specific preferences on banana plants as preliminary experiments. Our main focus was to investigate the oviposition preference of C. chalcites (Esper) adults by counting all present eggs and larvae on the plant seven days after adult release into cages. The combination of two plants through three growing stages (young plant, mature plants without bunch and mature plants with bunch) were tested over 48 banana plants into six different field cages. Significant difference in ovipositional behaviour was found between the three growing stages of banana plants. In order to detect C. chalcites populations on banana plantations, it can be suggested to look firstly to the 5th leaf on young plants, secondly to the 8th leaf on pants with bunch, and finally plants without bunch. In all cases, more eggs and first instar larvae were found on young plants and on the underside of the leaves. [ABSTRACT FROM AUTHOR]

Among the ever-growing number of self-replicating proteins involved in neurodegenerative diseases, the prion protein PrP remains the most infamous for its central role in transmissible spongiform encephalopathies (TSEs). In these diseases, pathogenic prions propagate through a seeding mechanism, where normal PrPC molecules are converted into abnormally folded scrapie isoforms termed PrPSc. Since its discovery over 30 years ago, much advance has contributed to define the host-encoded cellular prion protein PrPC as a critical relay of prion-induced neuronal cell demise. A current consensual view is that the conversion of PrPC into PrPSc in neuronal cells diverts the former from its normal function with subsequent molecular alterations affecting synaptic plasticity. Here, we report that prion infection is associated with reduced expression of key effectors of the Notch pathway in vitro and in vivo, recapitulating changes fostered by the absence of PrPC. We further show that both prion infection and PrPC depletion promote drastic alterations in the expression of a defined set of Eph receptors and their ephrin ligands, which represent important players in synaptic function. Our data indicate that defects in the Notch and Eph axes can be mitigated in response to histone deacetylase inhibition in PrPC-depleted as well as prion-infected cells. We thus conclude that infectious prions cause a loss-of-function phenotype with respect to Notch and Eph signaling and that these alterations are sustained by epigenetic mechanisms. [ABSTRACT FROM AUTHOR]

Elastic strain is an effective and thus widely used parameter to control and modify the electrical, optical, and magnetic properties of crystalline solid-state materials. It has a large impact on device performance and enables adjusting the materials functionality. Here, we promote a micromechanical strain enhancement technology to achieve ultra-high strain in semiconductors. The here presented suspended membranes enable the accurate control of the strain on a wafer-scale by standard top-down fabrication methods making it attractive for both device applications and also, thanks to the simplicity of the method, for fundamental research. This review aims at discussing the process of strain enhancement and its usage as an investigation platform for strain-related physical properties. Furthermore, we present design rules and a detailed analysis of fracture effects limiting the strain enhancement. [ABSTRACT FROM AUTHOR]

A simple kinetic model, with only three fitting parameters, for several enzyme productions in Petri dishes by solid-state fermentation is proposed in this paper, which may be a valuable tool for simulation of this type of processes. Basically, the model is able to predict temporal fungal enzyme production by solid-state fermentation on complex substrates, maximum enzyme activity expected and time at which these maxima are reached. In this work, several fermentations in solid state were performed in Petri dishes, using four filamentous fungi grown on different agro-industrial residues, measuring xylanase, exo-polygalacturonase, cellulose and laccase activities over time. Regression coefficients after fitting experimental data to the proposed model turned out to be quite high in all cases. In fact, these results are very interesting considering, on the one hand, the simplicity of the model and, on the other hand, that enzyme activities correspond to different enzymes, produced by different fungi on different substrates. [ABSTRACT FROM AUTHOR]

In extensive nonreperfused myocardial infarction (MI), remote fibrosis has been documented. Early reperfusion by primary angioplasty represents the gold standard method to minimize the extension of the infarction. We aimed to ascertain whether fibrosis also affects remote regions in reperfused MI in swine and patients. Swine were subjected to a transient occlusion of the left anterior descending artery followed by 1-week or 1-month reperfusion. Collagen content in the remote area macroscopically, microscopically, by magnetic resonance microimaging, and at the molecular level was similar to controls. In patients with previous MI, samples from autopsies displayed a significant increase in collagen content only in the infarct region. In patients with previous MI submitted to cardiac magnetic resonance-T1 mapping, the extracellular volume fraction in remote segments was similar to that for controls. In all scenarios, the remote region did not show a significant increase of collagen content in comparison with controls. [ABSTRACT FROM AUTHOR]

Although the relationship between hematopoietic stem cells and progenitor populations has been investigated extensively under steady-state conditions, the dynamic response of the hematopoietic compartment during acute infection is largely unknown. Here we show that after infection of mice with Plasmodium chabaudi, a c-Kithi progenitor subset positive for interleukin 7 receptor-α (IL-7Rα) emerged that had both lymphoid and myeloid potential in vitro. After being transferred into uninfected alymphoid or malaria-infected hosts, IL-7Rα+c-Kithi progenitors generated mainly myeloid cells that contributed to the clearance of infected erythrocytes in infected hosts. The generation of these infection-induced progenitors was critically dependent on interferon-γ (IFN-γ) signaling in hematopoietic progenitors. Thus, IFN-γ is a key modulator of hematopoiesis and innate and adaptive immunity during acute malaria infection. [ABSTRACT FROM AUTHOR]

A line of hamster embryo cells fused with inactivated Sendai virus was infected with a strain of fixed rabies virus. The growth of rabies virus in such a system produced a characteristic cytopathic effect. [ABSTRACT FROM AUTHOR]

Immunotherapies targeting the PD-1/PD-L1 axis are now a mainstay in the clinical management of multiple cancer types, however, many tumors still fail to respond. CCL2 is highly expressed in various cancer types and has been shown to be associated with poor prognosis. Inhibition or blockade of the CCL2/CCR2 signaling axis has thus been an area of interest for cancer therapy. Here we show across multiple murine tumor and metastasis models that CCR2 antagonism in combination with anti-PD-1 therapy leads to sensitization and enhanced tumor response over anti-PD-1 monotherapy. We show that enhanced treatment response correlates with enhanced CD8+ T cell recruitment and activation and a concomitant decrease in CD4+ regulatory T cell. These results provide strong preclinical rationale for further clinical exploration of combining CCR2 antagonism with PD-1/PD-L1-directed immunotherapies across multiple tumor types especially given the availability of small molecule CCR2 inhibitors and antibodies. Investigating signalling induced by the cytokine CCL2 as a therapeutic target, Tu et al demonstrate that blockade of the CCL2 receptor, CCR2 enhances CD8+ T cell recruitment and activation and the therapeutic efficacy of PD-1 inhibition in tumours. [ABSTRACT FROM AUTHOR]

Recent studies have shown how intestinal parasites can modulate gut microbiota. This observation is not surprising since the human intestinal lumen, like any other niche, is a battlefield of microbial competition, and Eukaryotes can affect bacterial populations. Intestinal pathogenic protist has been associated with reshaping the microbial community structure; however, the interactions between the colonic bacterial communities and parasites like Blastocystis spp., Entamoeba coli, and Endolimax nana have been poorly studied. In this work, we studied the distal intestinal bacterial microbiota of 49 children attending 7 public daycare centers in Medellin, Colombia, and compared the bacterial microbiota structure in the presence or absence of the protists Blastocystis spp., E. coli, and E. nana. Parasite colonization was associated with an increase in bacterial richness. Moreover, Blastocystis spp. presented a positive relationship with Prevotella, since this bacterium was selectively enriched in children carrying it. Remarkably, the E. coli colonized children showed a microbial profile that was closer to uninfected controls, although some bacterial taxa displayed to be enriched. This is the case for Akkermansia, which showed to be favored in E. coli colonized individuals, while notably reduced in the Blastocystis spp. parasitized group. [ABSTRACT FROM AUTHOR]

In this study, we present a combined small-angle neutron and X-ray scattering (SANS and SAXS) study of the nanoscale structure of cortical bone specimens from three different species. The variation of the scattering cross section of elements across the periodic table is very different for neutrons and X-rays. For X-rays, it is proportional to the electron density while for neutrons it varies irregularly with the atomic number. Hence, combining the two techniques on the same specimens allows for a more detailed interpretation of the scattering patterns as compared to a single-contrast experiment. The current study was performed on bovine, porcine and ovine specimens, obtained in two perpendicular directions with respect to the main axis of the bone (longitudinal and radial) in order to maximise the understanding of the nanostructural organisation. The specimens were also imaged with high resolution micro-computed tomography (micro-CT), yielding tissue mineral density and microstructural orientation as reference. We show that the SANS and SAXS patterns from the same specimen are effectively identical, suggesting that these bone specimens can be approximated as a two-component composite material. Hence, the observed small-angle scattering results mainly from the mineral-collagen contrast, apart from minor features associated with the internal collagen structure. [ABSTRACT FROM AUTHOR]