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Background Individuals with incomplete spinal cord injury (iSCI) demonstrate greater postural sway and increased dependency on vision to maintain balance compared to able-bodied individuals. Research on standing balance after iSCI has focused on the joint contribution of the lower limbs; however, inter-limb synchrony in quiet standing is a sensitive measure of individual limb contributions to standing balance control in other neurological populations. It is unknown if and how reduced inter-limb synchrony contributes to the poor standing balance of individuals with iSCI. Research question How does an iSCI affect inter-limb synchrony and weight-bearing symmetry in standing? Methods Eighteen individuals with non-progressive motor iSCI and 15 age- and sex-matched able-bodied individuals (M-AB) were included in the study. Participants stood in a standardized position on two adjacent force plates in eyes open and closed conditions for 70 s per condition. Net centre-of-pressure (COP) root mean square (RMS), net COP velocity, COP inter-limb synchrony (i.e. cross-correlation between left and right COP), and weight-bearing asymmetry (i.e. vertical force from each limb over total vertical force) were calculated. Muscle strength of the lower limbs was assessed with manual muscle testing. Results Individuals with iSCI demonstrated reduced inter-limb synchrony when standing with eyes open and eyes closed, but did not differ to M-AB with respect to weight-bearing asymmetry. They also produced greater net COP RMS and velocity when compared to M-AB. Muscle strength of the two lower limbs demonstrated an overall asymmetry in individuals with iSCI. Significance Individuals with iSCI demonstrated impaired balance control as evidenced by reduced inter-limb synchrony and greater COP RMS and velocity compared to M-AB individuals. This increased understanding of how balance control is impaired following iSCI may inform balance assessment and intervention for this population. Future work examining the association between inter-limb synchrony and the occurrence of falls in iSCI is warranted.

This work addressed the gas–liquid (G/L) mass transfer limitation coming from the increasing liquid height and the circumvention of the limitation by introducing a sieve tray in a bubble column. Either monoethylene glycol (MEG) solution or n-hexane was adopted as a liquid phase and argon was used as a gas phase in the bubble column. The gas holdup and the mass transfer coefficient became lowered by the static liquid height increase due to the increase of bubble size. The loss of mass transfer was overcome by installing a sieve tray inside the column. The two sieve trays with different hole sizes were employed and both bubble diameter and standard deviation of pressure were investigated to understand the effect of the sieve tray on the mass transfer. With a smaller size hole sieve (1 mm), the mass transfer deteriorated in both liquid systems (MEG and n-hexane) due to the formation of gas cap below the sieve while with a larger hole sieve (3 mm), it was enhanced because of the reduction of bubble diameters without any gas cap formation. However, it was found that the sieve tray effect was weakened when the flow regime changes from homogeneous to heterogeneous.

In situ transesterification (direct conversion) of microalgal cells is a promising method to produce biodiesel from microalgae because it integrates the oil extraction and conversion process in one step. Not only biodiesel but also a few biochemicals can be produced through this process because both lipids and carbohydrates are converted under acidic conditions. Levulinic acid ester (levulinate) is one of the byproducts of in situ transesterification, which can be used as an additive in fuels or fragrances. This study investigated the effect of cell composition and reactive variables on the productivity of levulinic acid ester. The cell compositions of microalgal strains were compared between Nannochloropsis and Chlorella , and more levulinate was produced from carbohydrate-rich Chlorella cells. Both reaction temperature and acid concentration highly affected the levulinate yield, whereas the type of alcohols did not have much influence on the yield. Consequently, more than 40 mol% glucose inside the cell was converted to levulinate with a 15 v% sulfuric acid concentration at 130 °C.

Background & Aims Immunotherapies that induce T-cell responses have shown efficacy against some solid malignancies in patients and mice, but these have little effect on pancreatic ductal adenocarcinoma (PDAC). We investigated whether the ability of PDAC to evade T-cell responses induced by immunotherapies results from the low level of immunogenicity of tumor cells, the tumor's immunosuppressive mechanisms, or both. Methods Kras G12D/+ ;Trp53 R172H/+ ;Pdx-1-Cre (KPC) mice, which develop spontaneous PDAC, or their littermates (controls) were given subcutaneous injections of a syngeneic KPC-derived PDAC cell line. Mice were then given gemcitabine and an agonist of CD40 to induce tumor-specific immunity mediated by T cells. Some mice were also given clodronate-encapsulated liposomes to deplete macrophages. Tumor growth was monitored. Tumor and spleen tissues were collected and analyzed by histology, flow cytometry, and immunohistochemistry. Results Gemcitabine in combination with a CD40 agonist induced T-cell−dependent regression of subcutaneous PDAC in KPC and control mice. In KPC mice given gemcitabine and a CD40 agonist, CD4 + and CD8 + T cells infiltrated subcutaneous tumors, but only CD4 + T cells infiltrated spontaneous pancreatic tumors (not CD8 + T cells). In mice depleted of Ly6C low F4/80 + extratumoral macrophages, the combination of gemcitabine and a CD40 agonist stimulated infiltration of spontaneous tumors by CD8 + T cells and induced tumor regression, mediated by CD8 + T cells. Conclusions Ly6C low F4/80 + macrophages that reside outside of the tumor microenvironment regulate infiltration of T cells into PDAC and establish a site of immune privilege. Strategies to reverse the immune privilege of PDAC, which is regulated by extratumoral macrophages, might increase the efficacy of T-cell immunotherapy for patients with PDAC.

Future chip multiprocessors (CMPs) may have hundreds to thousands of threads competing to access shared resources, and will require quality-of-service (QoS) support to improve system utilization. This paper introduces Globally-Synchronized Frames (GSF), a framework for providing guaranteed QoS in on-chip networks in terms of minimum bandwidth and maximum delay bound. The GSF framework can be easily integrated in a conventional virtual channel (VC) router without significantly increasing the hardware complexity. We exploit a fast on-chip barrier network to efficiently implement GSF. Performance guarantees are verified by analysis and simulation. According to our simulations, all concurrent flows receive their guaranteed minimum share of bandwidth in compliance with a given bandwidth allocation. The average throughput degradation of GSF on an 8x8 mesh network is within 10% compared to the conventional best-effort VC router.

Diamond like carbon (DLC) films were synthesized by closed-field unbalanced magnetron sputtering (CFUBM) using carbon targets in Ar and Ar/C2H2 atmosphere. The deposition rate, structure and mechanical properties of these films were studied as a function of applied bias voltage on the substrate during deposition. The film structures were investigated using Raman spectroscopy. The hardness and elastic modulus were measured by nano-indentation tests and the friction coefficient of DLC films was measured by a ball-on-disc type wear tester. Raman analysis showed that sp3/sp2 ratio in DLC films changed with increasing substrate bias voltage. Hydrogenated DLC films deposited at the bias of −200 V exhibited a maximum hardness of 28 GPa and a relatively low friction coefficient of about 0.1.