High Degree Of Alignment Research Articles

Developing 3D Organized Human Cardiac Tissue within a Microfluidic Platform.

The leading cause of death worldwide persists as cardiovascular disease (CVD). However, modeling the physiological and biological complexity of the heart muscle, the myocardium, is notoriously difficult to accomplish in vitro. Mainly, obstacles lie in the need for human cardiomyocytes (CMs) that are either adult or exhibit adult-like phenotypes and can successfully replicate the myocardium's cellular complexity and intricate 3D architecture. Unfortunately, due to ethical concerns and lack of available primary patient-derived human cardiac tissue, combined with the minimal proliferation of CMs, the sourcing of viable human CMs has been a limiting step for cardiac tissue engineering. To this end, most research has transitioned toward cardiac differentiation of human induced pluripotent stem cells (hiPSCs) as the primary source of human CMs, resulting in the wide incorporation of hiPSC-CMs within in vitro assays for cardiac tissue modeling. Here in this work, we demonstrate a protocol for developing a 3D mature stem cell-derived human cardiac tissue within a microfluidic device. We specifically explain and visually demonstrate the production of a 3D in vitro anisotropic cardiac tissue-on-a-chip model from hiPSC-derived CMs. We primarily describe a purification protocol to select for CMs, the co-culture of cells with a defined ratio via mixing CMs with human CFs (hCFs), and suspension of this co-culture within the collagen-based hydrogel. We further demonstrate the injection of the cell-laden hydrogel within our well-defined microfluidic device, embedded with staggered elliptical microposts that serve as surface topography to induce a high degree of alignment of the surrounding cells and the hydrogel matrix, mimicking the architecture of the native myocardium. We envision that the proposed 3D anisotropic cardiac tissue-on-chip model is suitable for fundamental biology studies, disease modeling, and, through its use as a screening tool, pharmaceutical testing.

Hydrodynamic and electrical interactions in electrospinning of polymer fibers over a liquid collector

AbstractThis paper reports the morphology manipulation of electrospun polymer fibers using a rotating water collector. The hydrodynamic and electrical interactions of the employed liquid collector and electrospun fibers are investigated to reveal their effects on the fiber morphology. The experimental results show that hydrodynamic interaction is the dominant factor. Particularly, a higher flow velocity of the liquid collector produces a fiber mat with a larger area and lower density consisting of electrospun fibers with a smaller diameter and higher degree of alignment. By applying a rotation speed of 600 rpm, a fiber mat area can be increased by ~166% compared with the stationary solid collector while an area fraction is reduced to 45.2%. Furthermore, it is found that the electrical interaction only affects the area and density of the fiber mat. The higher electrical conductivity of the liquid collector leads to a smaller fiber mat area with higher fiber density. The present study offers a new paradigm for precisely manipulating the morphology of electrospun polymer fibers, thus leading to a broad range of applications.

(Invited) Globally Aligned, Wafer-Scale Deposition of Carbon Nanotubes Via Interfacial Assembly

Floating evaporative self-assembly (FESA) is a solution-based technique for fabricating highly-aligned semiconducting carbon nanotube films.1,2 Field-effect transistors (FETs) based on carbon nanotubes aligned via FESA have exhibited current densities exceeding that of GaAs and Si, demonstrating the promise of this technique.3 However, the global uniformity of FESA films is poor, as the films are composed of stripes of aligned and randomly oriented carbon nanotubes. Additionally, this technique is inherently difficult to scale. In the work presented here, we demonstrate a scalable technique to overcome the shortcomings of FESA and to achieve globally uniform films of aligned carbon nanotubes at desirable packing densities for FETs.In our technique, carbon nanotubes are continuously aligned across target substrates by lifting the substrates through a flowing nanotube ink/water interface. The ink/water interface collects and confines the nanotubes, which is vital to achieving a high degree of alignment. Polarized Raman spectroscopy mapping is used to quantify the degree of alignment in the resulting aligned nanotube films. The full width at half maximum (FWHM) of the alignment distribution within the films is 6.0° measured across a 1 mm2 area. We control the aligned carbon nanotube packing density from 0.2 to 59 µm-1 by varying the ink concentration from 0.1 to 100 µg mL-1. Using optimized conditions, we demonstrate the scalability of this technique by aligning carbon nanotubes across a 100 mm wide wafer. Charge transport measurements are performed using FETs with the aligned carbon nanotube films as the active channels, and the performance is compared to FETs based on FESA films.1. Jinkins, K., R. et al. Nanotube Alignment Mechanism in Floating Evaporative Self-Assembly. Langmuir 33, 13407–13414 (2017).2. Joo, Y., Brady, G. J., Arnold, M. S. & Gopalan, P. Dose-Controlled, Floating Evaporative Self-assembly and Alignment of Semiconducting Carbon Nanotubes from Organic Solvents. Langmuir 30, 3460–3466 (2014).3. Brady, G. J. et al. Quasi-ballistic carbon nanotube array transistors with current density exceeding Si and GaAs. Sci. Adv. 2, (2016).

Doping Liquid Crystals of Colloidal Inorganic Nanotubes by Additive-Free Metal Nanoparticles.

Doping liquid-crystal phases with nanoparticles is a fast-growing field with potential breakthroughs due to the combination of the properties brought by the two components. One of the main challenges remains the long-term stability of the hybrid system, requiring complex functionalization of the nanoparticles at the expense of their self-assembly properties. Here we demonstrate the successful synthesis of additive-free noble-metal nanoparticles at the surface of charged inorganic nanotubes. Transmission electron microscopy and UV-visible spectroscopy confirm the stabilization of metallic nanoparticles on nanotubes. Meanwhile, the spontaneous formation of liquid-crystals phases induced by the nanotubes is observed, even after surface modification with metallic nanoparticles. Small-angle X-ray scattering experiments reveal that the average interparticle distance in the resulting hybrids can be easily modulated by controlling electrostatic interactions. As a proof-of-concept, we demonstrate the effectiveness of our method for the preparation of homogeneous transparent hybrid films with a high degree of alignment.

Reduced Graphene Oxide Fibers for Guidance Growth of Trigeminal Sensory Neurons.

Neurite alignment and elongation play special roles in the treatment of neuron disease, design of tissue engineering implants, and bioelectrodes applications. For instance, the trigeminal neurons (TGNs) free nerve endings are a key component of the pulp-dentin complex. The reinnervation of the pulp canal space requires the recruitment of apically positioned free nerve endings through axonal guidance. Many studies have been carried to develop patterned two-dimensional substrates or three-dimensional scaffolds with aligned topographical structures to guide axonal growth. However, most of the strategies are either complicated/inconvenient in process or time-/cost-sacrifice. One-step dimensionally confined hydrothermal (DCH) technique has been considered an effective and facile approach to fabricate reduced graphene oxide fibers (rGOFs), and the rGOFs have shown significant potential in regulating neural stem cells differentiation toward neurons. Here, inspired by the relationship between the lateral size of GO nanosheets and the electrical conductivity of GO films made from GO sheets as a building block, we fabricated surface conductivity and topography-controlled rGOFs based on the DCH method. Well "self-patterned" directional channel structure of rGOF showed outstanding ability to improve the neurofilament alignment and migration, with the cell deviation angle less than 10° for over 90% of the cells, while a porous surface structure tended to form neuron nets. All of the rGOF possessed excellent cytocompatibility with TGNs. Our results underlined the high degree of alignment of topographical cues in guidance of neurite over high electrical conductivity. The as-prepared rGOFs could be used in many areas including biosensing, electrochemistry, energy, and peripheral or central nerve tissue engineering.

False amoxicillin/clavulanic acid susceptibility in Bacteroides fragilis using gradient strip tests

BackgroundRepeatedly, too low MIC results were obtained in Bacteroides fragilis quality assessment strains, using gradient strip tests with a ratio of amoxicillin:clavulanic acid of 2:1. We aimed to find the most accurate available gradient strip tests for susceptibility testing of amoxicillin/clavulanic acid in B. fragilis in comparison with agar dilution with EUCAST methodology and breakpoints. MethodsTwenty-seven clinical B. fragilis isolates were investigated using gold standard EUCAST amoxicillin/clavulanic acid agar dilution (fixed clavulanic acid concentration at 2 mg/L, with increasing amoxicillin concentrations) as well as three commercial gradient strip tests: XL (ratio), AUG (ratio) or AMC (fixed concentration). ResultsUsing agar dilution (fixed concentration), 19 isolates were susceptible, 1 isolate was susceptible increased exposure (I) and 7 isolates were resistant. Categorical agreement of the gradient strip tests with agar dilution (fixed concentration) was 70% for XL (ratio), 71% for AUG (ratio) and 89% for AMC (fixed concentration). Very major error rates in comparison with agar dilution (fixed concentration) were 100%, 0%, and 0%, respectively. ConclusionsEUCAST breakpoint usage in amoxicillin/clavulanic acid susceptibility tests for B. fragilis should be accompanied by EUCAST methodology. When using alternative methods such as gradient strip tests, a higher degree of alignment with EUCAST methodology, such as using fixed clavulanic acid concentrations, improves precision.

Determining the degree of alignment of prostate carcinoma in a rectal biopsy with radical prostatectomy in patients with prostate carcinoma

Background: The purpose of this study was to determine the degree of alignment of prostate carcinoma in a rectal biopsy with radical prostatectomy in patients with prostate carcinoma to determine which biopsy samples are consistent with surgical specimens. Methods: In this cross-sectional study, out of 122 patients with prostate cancer who had undergone radical prostatectomy surgery in Sina hospital of Tabriz 65 patients with clinical records and pathological reports of needle biopsy, and radical prostatectomy biopsy specimens were available.The required information was recorded in questionnaire made for this study, and then the pathologic report and Gleason score and lymph-vascular involvement of the specimens were determined separately and finally the Trans rectal pathology report of the biopsy was compared with the histopathology report of radical prostatectomy in each patient. Results: The most common Gleason score and radical prostatectomy score were 6 (41.5%) and 6(40%), respectively. The lowest frequency of Gleason score, radical of the prostatectomy, and Trans rectal biopsy score were 10 (3.1%), 8(4.6%)%), and 4(4.6%), respectively. Generally, 24.6% of the prostatectomy samples were similarly scored, while 63.1% reported Trans rectal biopsy specimens and 12.3% reported low Trans rectal biopsy. By grouping the samples into histopathology levels this association was 41.5% identical in terms of scores and 49.2% in excess and 9.2% in lower reporting. The most common histopathology degree was rarely (49%) in Trans rectal biopsy and moderate in 40% in radical prostatectomy about 43% of badly differentiated cancers in the surgical specimens remained at the same level and the highest reporting rates were in the group with a good degree of distinction (66%). The highest correlation between rectal biopsy samples and radical prostatectomy samples was at the 6th grade and lowest compliance rate was in 4th and 8th grades. Conclusion: The highest degree of alignment was in the bad differentiation group, which indicates the high predictive power of biopsy specimens at this degree of differentiation. The present study suggests that the size of the smaller prostate and the high pre-surgical PSA may be predictive of increasing the Gleason score after radical prostatectomy.

Microstructure Dictating Performance: Assembly of Graphene-Based Macroscopic Structures

ConspectusA wide range of groundbreaking advancements in electronics, photonics, nanocomposites, etc., have been achieved in the past decades due to the favorable attributes of single-layer graphene, including its record-breaking thermal conductivity, charge carrier mobility, fracture strength, and Young’s modulus. However, the realization of the potentials of macroscale graphene assemblies has remained challenging. The difficulties mainly lie within manipulating graphene sheets into an orderly intermolecular orientation and controlling the macroscopic ordering of the graphitic domains. Controlling the formation of graphene macroscopic structures and eliminating defects on both the nano- and microscales meanwhile optimizing performance is no easy feat. To address these microstructural issues in macroscopic graphene assemblies, multiple chemical, thermal, and mechanical approaches have been developed with a goal of overall performance enhancement. Therefore, in this Account we provide a brief review of our contributions in the microstructure engineering of macroscale graphene assemblies with the focus on graphene fibers (GFs), graphene papers (GPs), and other graphene-based assemblies with graphene oxide (GO) colloids as precursors.Building upon the developments in wet chemistry on assembling individual GO sheets into macroscopic structures, we successfully intercalated large GO sheets with small GO sheets, which increased compactness for wet-spun GFs without disturbing the sheet orientation and alignment of the large GO sheets. Increasing GO compactness during wet assembly allows for the increase of thermal and electrical conductivities as well as the mechanical strength of GFs at a single stroke. A high degree of alignment of graphene sheets with abundant sp2 carbon atoms is also necessary for achieving high thermal and electrical conductivities in graphene assemblies. Fine control of GO sheet alignment and orientation during the wet-spinning assembly is demonstrated through the shape and size confinement of fluidic flow channels. Utilizing this shear-stress-induced self-alignment strategy, the core–shell nonuniformity problem of GFs is addressed. Also, a correlation between the rheological properties and flow patterns of GO during wet-spinning and the microstructure of the GF assemblies is established.In addition to the orientation of graphene sheets, the crystallite size and macroscopic ordering within graphene assemblies also play important roles in determining their performances. Larger and highly oriented graphitic crystalline domains allow for higher thermal and electrical conductivities. By manipulating crystallite domain size and arrangement through high temperature graphitization, the electrical and thermal conductivities and Young’s modulus of GFs can be significantly enhanced. Fine temperature control can also help retain residual covalent cross-links between neighboring graphene sheets, meeting the need for balancing tensile strength, and thermal and electrical conductivities.The enhancement of GF mechanical, thermal, and electrical properties through optimizing the compactness and alignment of graphene sheets and the orientation of graphene crystallite domains have significantly improved the engineering capability of GFs. Such an improvement has been largely beneficial to flexible electronics research and has shown great potential in multifunctional composite materials. Similar strategies have also been emulated on related graphene-based materials such as graphene papers (GPs) and graphene fiber meshes (GFMs), yielding unique and favorable properties and performances.

Micropatterning Decellularized ECM as a Bioactive Surface to Guide Cell Alignment, Proliferation, and Migration.

Bioactive surfaces and materials have displayed great potential in a variety of tissue engineering applications but often struggle to completely emulate complex bodily systems. The extracellular matrix (ECM) is a crucial, bioactive component in all tissues and has recently been identified as a potential solution to be utilized in combination with biomaterials. In tissue engineering, the ECM can be utilized in a variety of applications by employing the biochemical and biomechanical cues that are crucial to regenerative processes. However, viable solutions for maintaining the dimensionality, spatial orientation, and protein composition of a naturally cell-secreted ECM remain challenging in tissue engineering. Therefore, this work used soft lithography to create micropatterned polydimethylsiloxane (PDMS) substrates of a three-dimensional nature to control cell adhesion and alignment. Cells aligned on the micropatterned PDMS, secreted and assembled an ECM, and were decellularized to produce an aligned matrix biomaterial. The cells seeded onto the decellularized, patterned ECM showed a high degree of alignment and migration along the patterns compared to controls. This work begins to lay the groundwork for elucidating the immense potential of a natural, cell-secreted ECM for directing cell function and offers further guidance for the incorporation of natural, bioactive components for emerging tissue engineering technologies.

Microstructural effects on failure modes in highly aligned short carbon fiber composites

AbstractAligned short carbon fiber (3‐5 mm) thermoplastic composites have potential for versatile manufacturability with little loss of mechanical properties in comparison to continuous reinforcement. Property prediction, failure behavior, and the effects of microstructural variation for these materials are not yet well explored. The finite element method was used to evaluate large domains encompassing characteristic discontinuous microstructures of thermoplastic matrix (PMMA) composites reinforced with short 3 to 5 mm carbon fibers with a high degree of alignment and conventional volume fractions. Virtual tests were performed on highly detailed microstructural simulations which included fiber‐matrix interface representation along with uniform or misaligned fiber morphologies. Stiffness, strength, and failure mechanisms were analyzed. It was shown that for ideal uniformly aligned short fiber reinforcements, the material maintains a high modulus within 95% of an equivalent continuous fiber‐reinforced polymer, along with relatively high strength at 80% of a carbon fiber reinforced polymer (CFRP). Failure modes depended on the toughness of the fiber‐matrix interface, transitioning from fiber rupture to a weaker fiber pullout failure for low interface properties. Simulations indicated that significant fiber misalignments on the order of 15% of fibers at ±15° off‐axis could sharply reduce local strength in the misaligned region to roughly 20% of the continuous fiber strength. Although partially affected by property dropoff owing to fiber off‐axis misalignment, this weakening was largely due to local matrix pockets in regions of high misalignment, which acted as failure initiation points.

Editorial: Governing the EU's climate and energy transition through the 2030 Framework

Editorial: Governing the EU's climate and energy transition through the 2030 Framework

Globally Aligned, Wafer-Scale Deposition of Carbon Nanotubes Via Interfacial Assembly

Floating evaporative self-assembly (FESA) is a solution-based technique for fabricating highly-aligned semiconducting carbon nanotube films.1,2 Field-effect transistors (FETs) based on carbon nanotubes aligned via FESA have exhibited current densities exceeding that of GaAs and Si, demonstrating the promise of this technique.3 However, the global uniformity of FESA films is poor, as the films are composed of stripes of aligned and randomly oriented carbon nanotubes. Additionally, this technique is inherently difficult to scale. In the work presented here, we demonstrate a scalable technique to overcome the shortcomings of FESA and to achieve globally uniform films of aligned carbon nanotubes at desirable packing densities for FETs.In our technique, carbon nanotubes are continuously aligned across target substrates by lifting the substrates through a flowing nanotube ink/water interface. The ink/water interface collects and confines the nanotubes, which is vital to achieving a high degree of alignment. Polarized Raman spectroscopy mapping is used to quantify the degree of alignment in the resulting aligned nanotube films. The full width at half maximum (FWHM) of the alignment distribution within the films is 6.0° measured across a 1 mm2 area. We control the aligned carbon nanotube packing density from 0.2 to 59 µm-1 by varying the ink concentration from 0.1 to 100 µg mL-1. Using optimized conditions, we demonstrate the scalability of this technique by aligning carbon nanotubes across a 100 mm wide wafer. Charge transport measurements are performed using FETs with the aligned carbon nanotube films as the active channels, and the performance is compared to FETs based on FESA films. 1. Jinkins, K., R. et al. Nanotube Alignment Mechanism in Floating Evaporative Self-Assembly. Langmuir 33, 13407–13414 (2017).2. Joo, Y., Brady, G. J., Arnold, M. S. & Gopalan, P. Dose-Controlled, Floating Evaporative Self-assembly and Alignment of Semiconducting Carbon Nanotubes from Organic Solvents. Langmuir 30, 3460–3466 (2014).3. Brady, G. J. et al. Quasi-ballistic carbon nanotube array transistors with current density exceeding Si and GaAs. Sci. Adv. 2, (2016).

Achieving High Alignment of Conjugated Polymers by Controlled Dip‐Coating

AbstractRealizing high polymer chain orientation and ordered thin‐film microstructures is beneficial for efficient charge transport of conjugated polymers. However, achieving a high alignment degree remains a challenge due to the sensitive nature of polymers to the processing conditions. By simply varying concentrations during a dip‐coating method, the component of polymer aggregates that adopt the planar backbones is enlarged and the ensuing assembly process is promoted. Herein, highly oriented polymer thin films of an isoindigo‐based conjugated polymer (PII‐2T) are prepared to enhance polymer orientation resulting in a drastic booming in carrier mobilities of organic field‐effect‐transistors (OFETs). The maximum mobility from aligned polymer films increases by up to 8.3 cm2 V−1 s−1, which is tenfold beyond the value evaluated from the unaligned direction or traditional spin‐coated samples. The enhanced orientation can also reduce the adverse effects of the contact resistance and facilitate charge transport in transistors. This work demonstrates that the highly aligned conjugated polymer films can be approached by the dip‐coating method while offers a latent cornerstone toward understanding the critical role of processing‐related parameters in determining morphology of solution‐coated thin films.

Advancing the Reference Narrative: Assessing Student Learning in Research Consultations

Abstract
 Objective – As reference services continue to evolve, libraries must make evidence based decisions about their services. This study seeks to determine the value of reference services in relation to student learning acquired during research consultations, by soliciting students’ and librarians’ perceptions of consultation success and examining the degree of alignment between them.
 Methods – The alignment of students’ learning outcomes (reported skills and knowledge acquired) with librarians’ expectations for student learning during consultations was assessed. An online questionnaire was conducted to gather responses from students who had sought consultation services; 20 students participated. In-person interviews took place with eight librarians who had provided these consultations. The online questionnaire for students included questions about students’ assessments of their self-identified learning goals through consultation with a librarian and their success at applying the knowledge and skills gained. Librarian interviews elicited responses about students’ prior research experience, librarians’ objectives for student learning, librarians’ perceptions of student learning outcomes, and perceived consultation success. The responses of both the students and the librarians were coded, matched, and compared.
 Results – Students and librarians both considered the consultation process to be successful in advancing learning objectives and research skills. All students reported that the consultations met their expectations, and most reported that the skills acquired were applicable to their projects and significantly improved the quality of their work. Librarians expressed confidence that students had gained competency in the following skill sets: finding sources, search strategy development, topic exploration, specific tool use, and library organization and access. A high degree of alignment was observed in the identification by both students and librarians of “finding sources” as the skill set most in need of enhancement or assistance, while some disparity was noted in the ranking of “search strategy development,” which librarians ranked second and students ranked last.
 Conclusion – The data demonstrate that both students and librarians perceived individual research consultations as an effective means to meet student learning expectations. Study findings suggest that as reference models continue to change and reference desk usage declines, research consultations remain a valuable element in a library’s service model and an efficient use of human resources.

Setting a research agenda for vascular Ehlers-Danlos syndrome using a patient and stakeholder engagement model

ObjectiveVascular Ehlers-Danlos syndrome (vEDS) is a rare, syndromic, heritable condition with life-threatening complications that include aortic and arterial aneurysms, dissection, and rupture. This study describes the formation of the vEDS Research Collaborative and methods used for stakeholder engagement. MethodsThe vEDS Research Collaborative was established with an engagement award from the Patient-Centered Outcomes Research Institute to create a framework for a patient-researcher partnership. Between October 1, 2017, and September 30, 2018, the Collaborative used the Patient-Centered Outcomes Research Institute Engagement Rubric to conduct stakeholder engagement to develop a patient-centered research agenda. A modified Delphi technique was used to develop and to refine research topics and questions, gathering input from all stakeholders during three rounds of feedback. ResultsFour topic areas were deemed important: mental health and quality of life issues, creating a care team, a holistic approach to vEDS management (medical and surgical), and pregnancy management. An online survey to rank a list of 12 research questions in these topic areas in order of importance was disseminated. The questions were ranked in order of importance through an online survey (N = 197 responses). The survey showed a high degree of alignment in the top priorities among stakeholders. There was a high degree of interest in pragmatic clinical trials evaluating medical management options and health-related quality of life outcomes. ConclusionsThe vEDS Research Collaborative has built a sustainable, coalition model of patient and stakeholder engagement, supported by the vEDS community, to identify a patient-centered, prioritized list of research questions. In articulating a shared vision for the future of vEDS research, the Collaborative has laid the groundwork for developing research protocols aligned with the highest priority questions for the individuals affected by this serious condition that can be translated into future clinical trials.

Influence of Magnetic Micelles on Assembly and Deposition of Porphyrin J-Aggregates.

Clusters of superparamagnetic iron oxide nanoparticles (SPIONs) have been incorporated into the hydrophobic core of polyethylene glycol (PEG)-modified phospholipid micelles. Two different PEG-phospholipids have been selected to guarantee water solubility and provide an external corona, bearing neutral (SPIONs@PEG-micelles) or positively charged amino groups (SPIONs@NH2-PEG-micelles). Under acidic conditions and with specific mixing protocols (porphyrin first, PF, or porphyrin last, PL), the water-soluble 5,10,15,20-tetrakis-(4-sulfonatophenyl)-porphyrin (TPPS) forms chiral J-aggregates, and in the presence of the two different types of magnetic micelles, an increase of the aggregation rates has been generally observed. In the case of the neutral SPIONs@PEG-micelles, PL protocol affords a stable nanosystem, whereas PF protocol is effective with the charged SPIONs@NH2-PEG-micelles. In both cases, chiral J-aggregates embedded into the magnetic micelles (TPPS@SPIONs@micelles) have been characterized in solution through UV/vis absorption and circular/linear dichroism. An external magnetic field allows depositing films of the TPPS@SPIONs@micelles that retain their chiroptical properties and exhibit a high degree of alignment, which is also confirmed by atomic force microscopy.

Combining Individual and Firm-level Human Capital Resources: The Creation and Performance Benefits of Human Capital Alignment

We investigate how alignment between firm and individual-level human capital resources influences firm performance. We argue that a high degree of alignment between the firm and individual levels increases human capital utilization, coordination, and transfer. Drawing on Utah residential real estate data from 1996-2014, we find that brokerages with higher brokerage-agent human capital alignment engage in more transactions than brokerages with lower alignment. These benefits increase with firm size. We also find that individual-level human capital similarity in the first year significantly influences firm-individual alignment in subsequent years. These results suggest that managers from founding onward must carefully craft and manage alignment in individual and firm-level human capital resources to generate persistent performance advantages that are resistant to turnover and difficult for competitors to replicate.

Synthesis of Evaluations in South Sudan

South Sudan is one the largest recipients of official development assistance. Given the complexity of the operational environment, there is a need to learn from the lessons gained to-date. This article seeks to enable better-informed decision making based on a synthesis from humanitarian and development evaluation reports, which offer insight for engagement in other fragile and conflict-affected states. Experimental methods were utilised to identify evaluation reports. The synthesis finds that projects would be better designed if they allocated time and resources to obtain additional information, integrated systems thinking to account for the broader context, and engaged with the gendered nature of activities and impacts. Implementation can be strengthened if seasonality is taken into account, if modalities are more flexible, and if a greater degree of communication and collaboration between partners develops. Sustainability and long-term impact require that there is a higher degree of alignment with the government, longer-term commitments in programming, a recognition of trade-offs, and a clear vision and strategy for transitioning capacities and responsibilities to national actors. While actors in South Sudan have been slow to act on lessons learned to-date, the lessons drawn from evaluation reports in South Sudan offer direction for new ways forward, many of which have been concurrently learned by a diverse set of donors and organisations.

Alignment of Alzheimer's disease amyloid β-peptide and klotho.

The cause of Alzheimer’s disease (AD) is poorly understood. In 1991, the amyloid hypothesis postulated that β-amyloid (Aβ) accumulation is a key element. It follows that clearing the brain of Aβ would be beneficial, which has not been the case. Therefore, Aβ is likely a result, not a cause, of AD and may be protective rather than harmful. The apolipoprotein E4 (apoE4) allele is the strongest genetic risk factor for AD. Klotho (KL), encoded by the KL gene, may be another AD-related protein. FGF21 is a circulating endocrine hormone, mainly secreted by the liver, mostly during fasting. FGF21 acts by binding to its receptor FGFR1 and co-receptor β-klotho. FGF21 is neuroprotective and could delay onset of AD. In the present study, the KL protein structure was examined to determine whether it may interact with Aβ. Protein data bank (pdb) entries for klotho and Aβ were searched on the RCSB Protein Data Bank for β-KL and AD amyloid β-peptide. The protein structures were superimposed and aligned on PYMOL v2.3.4 with the super command, which super aligns two protein selections. To evaluate the conservation and alignment of the Aβ and KL genomes across species, BLAT, the Blast-Like Alignment Tool of the UCSC Genome Browser, was used. The amino acid residues phe76-val96 of KL aligned closely with residues asp7-asn27 of Aβ. Cross-species comparison of KL revealed a high degree of alignment and conservation in the chimp and 27 other primates; however, less alignment and conservation were observed in the mouse, dog and elephant, even less in the chicken, western clawed frog (Xenopus tropicalis), zebrafish and lamprey. The current finding of amino acid residues phe76-val96 of klotho aligning closely with residues asp7-asn27 of Aβ suggests that Aβ can enhance the ability of klotho to draw FGF21 to regions of incipient neurodegeneration in AD. The problem arises with age. Older individuals do not heal or repair tissue damage as well as younger individuals. As neurodegeneration advances in an older individual, perhaps caused by neuroinflammation related to herpes simplex virus type 1, increasing amounts of amyloid are produced, forming an adhesive web, as the brain tries to hold the pathologic process in check. Meanwhile, the damage increases and spreads. Progressive neurodegeneration and cognitive decline are the outcome.

Dark matter halo shapes in the Auriga simulations

ABSTRACT We present shape measurements of Milky Way–sized dark matter haloes at redshift z = 0 in a suite of 30 zoom simulations from the Auriga project. We compare the results in full magnetohydrodynamics against dark matter–only simulations and find a strong influence of baryons in making dark matter haloes rounder at all radii compared to their dark matter–only counterparts. At distances ≲30 kpc, rounder dark matter distributions correlate with extended massive stellar discs and low-core gas densities. We measure the alignment between the halo and the disc shapes at different radii and find a high degree of alignment at all radii for most of the galaxies. In some cases, the alignment significantly changes as a function of radius implying that the halo shape twists; this effect correlates with recently formed bulges and is almost absent in the dark matter–only simulations. In a comparison against observational constraints, we find that $20{{\ \rm per\ cent}}$ of haloes in our sample are consistent with observational results derived from the Pal 5 stream that favours an almost spherical shape. Including baryons is a required element to achieve this level of agreement. In contrast, none of the simulations (neither dark matter only nor with baryons) match the constraints derived from the Sagittarius stream that favour an oblate dark matter halo.