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Human immunodeficiency virus (HIV) infection is associated with an increased risk of aggressive lymphoma, especially diffuse large B cell lymphoma (DLBCL). There are few data regarding HIV-associated DLBCL in China. Therefore, we analyzed the characteristics and outcomes of patients with HIV-associated DLBCL from our center. We retrospectively studied HIV-infected patients with DLBCL from 2011 to 2019. Data on HIV infection and lymphoma characteristics, treatments and outcomes were retrieved and analyzed. In 78 patients with HIV-associated DLBCL, most had poor performance status (PS) (74%), elevated lactate dehydrogenase (LDH) levels (95%), B symptoms (74%), advanced Ann Arbor stages (81%), bulky diseases (64%) and extranodal involvement (70%) at diagnosis. The median CD4+ T cell count was 162/µl, and 26 patients were already on combination antiretroviral therapy (cART) treatment at diagnosis of DLBCL. Elevated whole blood EBV DNA copy number was detected in 38 patients (66%, 38/58). Of the 45 patients evaluated at the end of treatment, 26 (58%) achieved CR, 6 (13%) achieved PR and 6 (13%) experienced progressive disease. The 2-year progression-free survival (PFS) and overall survival (OS) rates were 56.4% and 62.7%, respectively. Factors associated with decreased PFS and OS in univariate analysis were unfavorable PS and high international prognostic index. Elevated EBV DNA copy number was inclined to be associated with worse outcome. We did not observe a significant difference in survival between R-EPOCH and R-CHOP regimens. In our population, patients with HIV-associated DLBCL presented with aggressive characteristics and exhibited poor survival outcomes, even in the modern cART era.

Understanding colloid transport in subsurface environments is challenging because of complex interactions among colloids, groundwater, and porous media over several length scales. Here, we report a versatile method to assemble bead-based microfluidic porous media analogues with chemical heterogeneities of different configurations. We further study the transport of colloidal particles through a family of porous media analogues that are randomly packed with oppositely charged beads with different mixing ratios. We recorded the dynamics of colloidal particle deposition at the level of single grains. From these, the maximum surface coverage (θmax = 0.051) was measured directly. The surface-blocking function and the deposition coefficient (kpore = 3.56 s-1) were obtained. Using these pore-scale parameters, the transport of colloidal particles was modeled using a one-dimensional advection-dispersion-deposition equation under the assumption of irreversible adsorption between oppositely charged beads and colloids, showing very good agreement with experimental breakthrough curves and retention profiles at the scale of the entire porous medium analogue. This work presents a new approach to fabricate chemically heterogeneous porous media in a microfluidic device that enables the direct measurement of pore-scale colloidal deposition. Compared with the conventional curve-fitting method for deposition constant, our approach allows quantitative prediction of colloidal breakthrough and retention via coupling of direct pore-scale measurements and an advection-dispersion-deposition model.

International audience; Direct contact membrane distillation (DCMD) is a promising means of concentrating brines to their saturation limit. During that process, membrane spacers play a key role in temperature polarization, concentration polarization, and mineral scaling. These interactions are not well understood, because they are difficult to study experimentally and numerically, and the flow regimes are not fully charted. We consequently develop a tailored in-house CFD code that simulates unsteady two-dimensional heat and mass transport in plate-and-frame DCMD systems with cylindrical spacers. The code uses a combination of finite-volume methods in space, projection methods in time, and recent advances in immersed boundary methods for the spacer surfaces. Using the code, we explore how the transition to unsteady laminar vortex shedding affects polarization and permeate production of DCMD systems. We show that the impact of spacers can be explained by examining the various steady and unsteady vortical flow structures generated in the bulk and near the membranes. Overall, we show that though unsteady vortex structures tend to mix temperature polarization layers with the bulk, they are not similarly able to mix the concentration layers. Rather, vortical structures tend to create regions of preferential salt accumulation. In the vortex shedding regime, the net result is that spacers often increase vapor production at the expense of increasing the risk of mineral scaling.

Reverse Osmosis has important applications to seawater desalination and advanced water treatment. Its efficiency depends, however, on unsteady fluid flow and solute transport that are challenging to simulate. The challenges arise due to interactions between solute boundary layers and unsteady vortical flow structures generated by complicated geometries. These flow structures also interact with semi-permeable membranes through which the permeate flow depends on the local pressure. We show that this additional pressure coupling causes the temporal accuracy of traditional projection methods to drop to first-order. We track the source of this accuracy drop to the treatment of viscous terms in the derivation of the Poisson equation used to update the velocity and pressure fields. This allows us to propose a modified projection method that recovers second-order temporal accuracy. Finally, we show that the modified projection method can be coupled to convective outlet conditions and immersed boundary conditions to simulate reverse osmosis in steady and unsteady flow regimes.

Environmental-friendly nanocellulose films with excellent mechanical strength have attracted extensive attention in the gel polymer electrolytes (GPEs) for lithium-ion batteries. However, their dense structure causes poor electrolyte uptake capacity. In this research, carboxymethylated nanocellulose (CMNC) with a strong swelling behavior and anionic character was chosen as raw materials to not only improve the electrolyte absorption ability and lithium ion transfer number of the resulting GPEs but also avoid short circuits by their dense morphology. Further crosslinking by epichlorohydrin and solvent casting, CCMNC films were obtained, which exhibited excellent mechanical strength (36.46 to 67.45 MPa), thermal stability (up to 250 °C) and flexibility. After electrolyte uptaking, the optimal GCCMNC GPE at an ECH content of 5 wt% displayed an electrolyte uptake ratio, ionic conductivity, lithium ion transfer number, and electrochemical stability window of 312 wt%, 3.93 mS cm−1, 0.82, and 4.65 V, respectively. Particularly, the initial discharge capacity of our assembled Li/GCCMNC-5/NCM523 battery was 151.4 mAh g−1. After 50 cycling, the cell still maintained a capacity of 74 % and a coulombic efficiency of 98 %. The good mechanical strength, thermal stability and electrochemical properties of our designed GCCMNC GPE indicated its promising application in the lithium-ion batteries.

Membrane distillation (MD) is a membrane-based thermal desalination process capable of treating hypersaline brines. Standard MD systems rely on preheating the feed to drive the desalination process. However, relying on the feed to carry thermal energy is limited by a decline of the thermal driving force as the water moves across the membrane, and temperature polarization. In contrast, supplying heat directly into the feed channel, either through the membrane or other channel surfaces, has the potential of minimizing temperature polarization, increasing single-pass water recoveries, and decreasing the number of heat exchangers in the system. When solar thermal energy can be utilized, particularly if the solar heat is optimally delivered to enhance water evaporation and process performance, MD processes can potentially be improved in terms of energy efficiency, environmental sustainability, or operating costs. Here we describe an MD process using layered composite membranes that include a high-thermal-conductivity layer for supplying heat directly to the membrane-water interface and the flow channel. The MD system showed stable performance with water flux up to 9 L/m2/hr, and salt rejection >99.9% over hours of desalinating hypersaline feed (100 g/L NaCl). In addition to bench-scale system, we developed a computational fluid dynamics model that successfully described the transport phenomena in the system.

Membrane distillation is an emerging desalination process with important applications to the energy-water nexus. Its performance depends, however, on heat and mass transport phenomena that are uniquely challenging to simulate. Difficulties include two adjacent channel flows coupled by heat and mass transport across a semi-permeable membrane. Within the channels, heat and mass boundary layers interact with the membrane surface and vortical flow structures generated by complicated geometries. The presence of multiple inlets and outlets also complicates the application of mass-conserving outlet conditions. Moreover, even small amounts of outlet noise affect the resolution of important near-membrane fluid velocities. We show these phenomena can be simulated to second-order spatial and temporal accuracy using finite volume methods with immersed boundaries and projection methods. Our approach includes a projection method that staggers the coupled channel flows and applies Robin boundary conditions to facilitate mass conservation at the outlets. We also develop an immersed boundary method that applies Neumann boundary conditions to second-order spatial accuracy. The methods are verified and validated against manufactured solutions and theoretical predictions of vortex shedding. They are then applied to the simulation of steady and unsteady transport phenomena in membrane distillation. The methods have important applications to the broad field of chemical engineering and deal with long-standing issues in both theoretical and computational fluid dynamics.

Direct Contact Membrane Distillation (DCMD) has emerged as a promising means of concentrating brines to their saturation limit. To date, computational fluid dynamics (CFD) studies of DCMD focus primarily on temperature polarization. However, when treating hypersaline brines, concentration polarization is an additional challenge that reduces system efficiency and leads to mineral scaling. To study coupled temperature and concentration polarization in the DCMD treatment of hypersaline brines, we develop an experimentally validated two-dimensional CFD code that simulates heat and mass transport in plate-and-frame DCMD systems. We then perform a comprehensive parametric study of polarization phenomena for a wide range of feed and distillate operating conditions, system length, and co-current versus counter-current operation. We also investigate the system-level performance by measuring the average permeate flux, single-pass water recovery, maximum concentration polarization coefficient, and gained output ratio of DCMD systems with heat recovery. Though the transmembrane vapor flux is small, we observe dramatic increases in solute concentration at the membrane surface, exceeding 1.6 times the feed value. The temperatures, concentration, and vapor flux vary considerably in the downstream direction, and are poorly approximated by common Nusselt and Sherwood correlations.

Human Pegivirus-1 (HPgV-1) may have a beneficial impact on disease progression in human immunodeficiency virus-1 (HIV-1) infection. However, analysis of the genotypic diversity of HPgV-1 and its relevance to the progression of HIV-1 disease remains limited. A total of 1062 HIV-1-infected individuals were recruited in all sixteen prefectures of Yunnan province, China. The reverse transcription nested polymerase chain reaction (RT-nPCR), phylogenetic analyses, and clinical data analyses were used to detect HPgV-1 infection, determine genotype, and analyze HPgV-1 genotype impact on HIV-1 disease progression. The overall positive rate of HPgV-1 RNA was 23.4% (248/1062), and the frequency of HPgV-1 infection in injecting drug users (IDUs) (28.5%, 131/460) was significantly higher than in heterosexuals (19.4%, 117/602). Multiple genotypes were identified in 212 subjects with successful sequencing for the E2 gene, including genotype 7 (55.7%), genotype 3 (34.9%), genotype 4 (4.7%), genotype 2 (3.3%), and an unclassified group (1.4%). Moreover, genotype 7 predominated in IDUs, whereas genotype 3 was the most common in heterosexuals. Our results revealed that HPgV-1 genotype 7 groups exhibited significantly lower HIV-1 viral load and higher CD4+ cell counts. This finding suggests that HPgV-1 genotype 7 may be associated with a better progression of HIV-1 disease.

To assess the prevalence and the characteristics of HIV-1 drug-resistance in pediatric HIV/AIDS cases with virological failure after free antiretroviral therapy in Yunnan Province.The data of clinical test and laboratory detection about free antiretroviral therapy in pediatric HIV/AIDS cases from 2005 to 2012 were collected. Then the detection of HIV genotypical drug resistance was performed for the plasmas samples whose viral load were over 1 000 copies/ml after the duration of antiretroviral therapy beyond 6 months. The prevalence and the characteristics of HIV-1 drug resistance were obtained for subsequent analysis.A total of 73 cases suffered virological failure among 729 cases while 53 cases exhibited the resistance for antiretroviral drugs.So the resistance ratio was 72.6% (53/73) and the general resistance ratio 7.3% (53/729). The prevalent mutations associated with drug resistance were M184V/I, K103N, T215F/Y, G190A, Y181C and K101E at the frequencies of 52.1% (38/73), 30.1% (22/73), 21.9% (16/73), 20.5% (15/73), 15.1% (11/73) and 12.3% (9/73) respectively. The percentage of resistance to NVP, 3TC, EFV, D4T, AZT and ABC was 61.6% (45/73) , 54.8% (40/73) , 47.9% (35/73) , 13.7% (10/73) , 12.3% (9/73) and 5.5% (4/73) respectively. One case developed intermediate resistance to LPV/r.The main causes of virological failure is drug resistance.So reducing the incidence and spread of HIV drug resistance is of vital importance in modern era of resource scarcity.