The oxygen reduction reaction (ORR) has a crucial function as the cathode reaction in energy-converting systems, such as fuel cells (FCs), which contributes to a sustainable energy supply. However, ...the current use of precious Pt-based electrocatalysts (ECs) is a major drawback for the economic viability of fuel cells. Hence, it is urgent to develop cost-effective and efficient electrocatalysts (ECs) without noble metals to substitute the Pt-based ECs. Herein, we report the preparation and application as ORR electrocatalysts of four new nanocomposites based on sandwich-type phosphotungstate (TBA)7H3Co4(H2O)2(PW9O34)2 (TBA-Co4(PW9)2) immobilized onto different carbon nanomaterials single-walled carbon nanotubes (SWCNT), graphene flakes (GF), carbon nanotubes doped with nitrogen (N-CNT), and nitrogen-doped few layer graphene (N-FLG). In alkaline medium, the four nanocomposites studied presented comparable onset potentials (0.77–0.90 V vs RHE), which are similar to that observed for Pt/C (0.91 V vs RHE). Higher diffusion-limiting current densities (j L,0.26V,1600 rpm = −168.3 mA cm–2 mg–1) were obtained for Co4(PW9)2@N-CNT, as compared to Pt/C electrode −130.0 mA cm–2 mg–1) and the other ECs (−45.0, −50.7, and −87.5 mA cm–2 mg–1 for Co4(PW9)2@SWCNT, Co4(PW9)2@GF, and Co4(PW9)2@N-FLG, respectively). All the Co4(PW9)2@CM ECs showed selectivity toward direct O2 reduction to water with the exception of Co4(PW9)2@GF where a mixture of the 2- and 4-electron mechanisms is observed. Furthermore, low Tafel slopes were obtained for all the nanocomposites (68–96 mV dec–1). Co4(PW9)2@CM ECs also showed excellent tolerance to methanol with no significant changes in current density, in contrast to Pt/C (decrease of ≈59% after methanol addition) and good long-term electrochemical stability with current retentions between 75 and 84%.
Antibody‐dependent cellular cytotoxicity (ADCC) is a set of mechanisms that target cells coated with IgG antibodies of the proper subclasses (IgG1 in the human) to be the prey of cell‐to‐cell ...cytolysis executed by immune cells expressing FcRIIIA (CD16A). These effectors include not only natural killer (NK) cells but also other CD16+ subsets such as monocyte/macrophages, NKT cells or γδ T cells. In cancer therapy, ADCC is exploited by antibodies that selectively recognize proteins on the surface of malignant cells. An approach to enhance antitumor activity is to act on effector cells so they are increased in their numbers or enhanced in their individual (on a cell per cell basis) ADCC performance. This enhancement can be therapeutically attained by cytokines (that is, interleukin (IL)‐15, IL‐21, IL‐18, IL‐2); immunostimulatory monoclonal antibodies (that is, anti‐CD137, anti‐CD96, anti‐TIGIT, anti‐KIR, anti‐PD‐1); TLR agonists or by adoptive infusions of ex vivo expanded NK cells which can be genetically engineered to become more efficient effectors. In conjunction with approaches optimizing IgG1 Fc affinity to CD16, acting on effector cells offers hope to achieve synergistic immunotherapy strategies.
The April 2017 issue of Immunology & Cell Biology contains a Special Feature on Cancer Immunotherapy. This series of reviews highlights some of the recent advances in mobilizing effective host immunity to cancer. Cancer immunotherapy is at a critical and exciting stage of development. Progress in our understanding of cancer immunotherapy has been dramatic over recent years and we have selected six articles to highlight in this Special Feature. The Special Feature begins with an overview of the approaches to targeting inflammation in the cancer microenvironment and follows with a focus of extracellular adenosine as a major immunosuppressive metabolite in tumours. Two subsequent articles detail advances in antibody engineering for engaging the ideal effector responses in tumours and the Special Feature finishes with two articles that explore new approaches in adoptive cellular therapy targeted at tumor and virus specific antigens in tumors. Immunology & C ell Biology thanks the coordinator of this Special Feature ‐ Mark Smyth ‐ for his planning and input.
•N-doped carbon nanotubes functionalized with Fe3O4 nanoparticles were successfully prepared.•The nanocomposite was successfully immobilized into GCE electrode.•The modified electrode showed ...electrocatalytic activity toward oxidation of ascorbic acid, dopamine and uric acid.•Good linear ranges with lower detection limits were obtained.
A new modified electrode based on N-doped carbon nanotubes functionalized with Fe3O4 nanoparticles (Fe3O4@CNT-N) has been prepared and applied on the simultaneous electrochemical determination of small biomolecules such as dopamine (DA), uric acid (UA) and ascorbic acid (AA) using voltammetric methods. The unique properties of CNT-N and Fe3O4 nanoparticles individually and the synergetic effect between them led to an improved electrocatalytic activity toward the oxidation of AA, DA and UA. The overlapping anodic peaks of these three biomolecules could be resolved from each other due to their lower oxidation potentials and enhanced oxidation currents when using the Fe3O4@CNT-N modified electrode. The linear response ranges for the square wave voltammetric determination of AA, DA and UA were 5–235, 2.5–65 and 2.5–85μmoldm−3 with detection limit (S/N=3) of 0.24, 0.050 and 0.047μmoldm−3, respectively. These results show that Fe3O4@CNT-N nanocomposite is a promising candidate of cutting-edge electrode materials for electrocatalytic applications.
We study the hub location and routing problem where we decide on the location of hubs, the allocation of nodes to hubs, and the routing among the nodes allocated to the same hubs, with the aim of ...minimizing the total transportation cost. Each hub has one vehicle that visits all the nodes assigned to it on a cycle. We propose a mixed integer programming formulation for this problem and strengthen it with valid inequalities. We devise separation routines for these inequalities and develop a branch-and-cut algorithm which is tested on CAB and AP instances from the literature. The results show that the formulation is strong and the branch-and-cut algorithm is able to solve instances with up to 50 nodes.
Chronic low back pain and biomechanical walking imbalances are closely related. It is relevant to identify if there are alterations in spatiotemporal gait patterns in subjects with CLBP (cases) ...versus healthy subjects (controls) to plan training interventions of motor control gait patterns, and thus allowing normal physical activity of the individual. This study is intended to identify if spatiotemporal alterations occur in the gait cycle in CLBP subjects (cases) compared with a control group (healthy patients) analyzed with an OptoGait LED sensors gait program. Method: A total of n = 147 participants: n = 75 cases (CLBP) and n = 72 healthy controls subjects were studied with OptoGait gait program. Results: Significant differences were found between the two groups and both feet in foot stride, for the differences of the total stride and contact, for gait cadence and total stride length of the gait cycle (p < 0.05). Conclusions: CLBP may alter some normal gait patterns measured by OptoGait; this finding presents imbalances in gait cycle as an underlying factor. The gait is part of daily life of any individual and it is an important physical activity in relation to the maintenance of an optimal state of health. In addition, future studies are deemed necessary.
La piedra de Inma la Magnánima Cunill, Inmaculada Rodríguez
Confluencia (Greeley, Colo.),
10/2021, Letnik:
37, Številka:
1
Journal Article
Recenzirano
Cada vez que vengo a Cádiz, tengo que pasear por la Laja de la playa de La Caleta. Tengo curiosidad, la próxima vez que vuelva a Cádiz, por ver dónde está la piedra de Inma la Magnánima. Ya entrado ...el año 2021, y antes de volvernos de las vacaciones en Cádiz, fuimos las tres a pasear por La Laja. Me entró de nuevo el gusanillo de mis aficiones arqueológicas, buscando cualquier ángulo recto que apareciera entre las rocas. Y así encontré cuatro piezas parecidas. Ninguna correspondía a mi piedra, pero esos restos me indicaron que sí, que era posible que yo permaneciera, para siempre, entre las huellas de las civilizaciones que se habían establecido en Cádiz: fenicios, púnicos, romanos... Y en mi mente reelaboré con los restos hallados aquel templo al que pertenecieron. Pero ya no era de dioses fenicios como Astarté o Kronion, sino esta vez de Inma la Magnánima, para quedarme para siempre en la playa de la Caleta.
Celotno besedilo
Dostopno za:
BFBNIB, DOBA, IZUM, KILJ, NMLJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Walking is part of daily life and in asymptomatic subjects it is relatively easy. The physiology of walking is complex and when this complex control system fails, the risk of falls increases. As a ...result, gait disorders have a major impact on the older adult population and have increased in frequency as a result of population aging. Therefore, the OptoGait sensor is intended to identify gait imbalances in pronating feet to try to prevent falling and injury by compensating for it with treatments that normalize such alteration. This study is intended to assess whether spatiotemporal alterations occur in the gait cycle in a young pronating population (cases) compared to a control group (non-pronating patients) analyzed with OptoGait.
a total of
= 142 participants consisting of
= 70 cases (pronators) and
= 72 healthy controls were studied by means of a 30 s treadmill program with a system of 96 OptoGait LED sensors.
Significant differences were found between the two groups and both feet in stride length and stride time, gait cycle duration and gait cadence (in all cases
< 0.05).
pronating foot posture alters normal gait patterns measured by OptoGait; this finding presents imbalance in gait as an underlying factor. Prevention of this alteration could be considered in relation to its relationship to the risk of falling in future investigations.
Interleukin-8 (IL8) is a chemokine produced by malignant cells of multiple cancer types. It exerts various functions in shaping protumoral vascularization and inflammation/immunity. We evaluated ...sequential levels of serum IL8 in preclinical tumor models and in patients to assess its ability to estimate tumor burden.
IL8 levels were monitored by sandwich ELISAs in cultured tumor cells supernatants, tumor-xenografted mice serum, and in samples from 126 patients with cancer. We correlated IL8 serum levels with baseline tumor burden and with treatment-induced changes in tumor burden, as well as with prognosis.
IL8 concentrations correlated with the number of IL8-producing tumor cells in culture. In xenografted neoplasms, IL8 serum levels rapidly dropped after surgical excision, indicating an accurate correlation with tumor burden. In patients with melanoma (n = 16), renal cell carcinoma (RCC; n = 23), non-small cell lung cancer (NSCLC; n = 21), or hepatocellular carcinoma (HCC; n = 30), serum IL8 concentrations correlated with tumor burden and stage, survival (melanoma, n = 16; RCC, n = 23; HCC, n = 33), and objective responses to therapy, including those to BRAF inhibitors (melanoma, n = 16) and immunomodulatory monoclonal antibodies (melanoma, n = 8). IL8 concentrations in urine (n = 18) were mainly elevated in tumors with direct contact with the urinary tract.
IL8 levels correlate with tumor burden in preclinical models and in patients with cancer. IL8 is a potentially useful biomarker to monitor changes in tumor burden following anticancer therapy, and has prognostic significance.
The formation of epithelial tissues requires both the generation of apical-basal polarity and the coordination of this polarity between neighbouring cells to form a central lumen. During de novo ...lumen formation, vectorial membrane transport contributes to the formation of a singular apical membrane, resulting in the contribution of each cell to only a single lumen. Here, from a functional screen for genes required for three-dimensional epithelial architecture, we identify key roles for synaptotagmin-like proteins 2-a and 4-a (Slp2-a/4-a) in the generation of a single apical surface per cell. Slp2-a localizes to the luminal membrane in a PtdIns(4,5)P(2)-dependent manner, where it targets Rab27-loaded vesicles to initiate a single lumen. Vesicle tethering and fusion is controlled by Slp4-a, in conjunction with Rab27/Rab3/Rab8 and the SNARE syntaxin-3. Together, Slp2-a/4-a coordinate the spatiotemporal organization of vectorial apical transport to ensure that only a single apical surface, and thus the formation of a single lumen, occurs per cell.
Celotno besedilo
Dostopno za:
DOBA, IJS, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
Rh catalysts with low Rh content were prepared by incipient wetness impregnation using NH43RhCl6·3H2O or RhCl3·3H2O as precursor salts, on CaO–SiO2 supports. All solids showed a high stability after ...48 h on stream for the dry reforming of methane with low carbon content, which made them suitable for obtaining ultrapure hydrogen in a membrane reactor. The methane conversion and hydrogen recovery were measured increasing the sweep gas flow rates to rise the driving force for hydrogen permeation. The catalyst with 0.36 wt.% of Rh showed a slight deactivation. However, the Rh(0.6)/CaO–SiO2 solid, in which the Rh impregnation was performed using NH43RhCl6·3H2O, exhibited an increase on CH4 conversion of 77% and a hydrogen recovery equal to 84%.
Nanoparticles of about 1.4–1.7 nm surface average diameter were detected for the reduced and used solids indicating that Rh is well dispersed and sintering was not produced after the catalytic tests. Rh particle sizes calculated by CO chemisorption were coincident with those measured by Transmission Electron Microscopy. Characterization by this technique and Laser Raman Spectroscopy of the solids used in membrane reactor revealed the formation of scarce carbon filaments. However, a surface re-oxidation was detected in the low loading catalyst used in the membrane reactor suggesting that it is the main cause for the decrease in the activity of the highly dispersed catalyst.
•Rh nanoparticles of about 1.4–1.7 nm were well dispersed on the CaO–SiO2 surface.•All the stable catalysts were applied in a membrane reactor for dry reforming of CH4.•The catalyst with 0.36 wt.% of Rh showed a slight deactivation.•No agglomeration of the Rh nanoparticles were observed by Transmission Electron Microscopy.•The main cause for the decrease in the activity was the oxidation of small Rh nanoparticles.
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