Search

The interactions between polymers and the immune system remains poorly controlled. In some instances, the immune system can produce antibodies specific to polymer constituents. Indeed, roughly half of pegloticase patients without immunomodulation develop high titers of anti-PEG antibodies (APA) to the PEG polymers on pegloticase, which then quickly clear the drug from circulation and render the gout treatment ineffective. Here, using pegloticase as a model drug, we show that addition of high molecular weight (MW) free (unconjugated) PEG to pegloticase allows us to control the immunogenicity and mitigates APA induction in mice. Compared to pegloticase mixed with saline, mice repeatedly dosed with pegloticase containing different MW or amount of free PEG possessed 4- to 12- fold lower anti-PEG IgG, and 6- to 10- fold lower anti-PEG IgM, after 3 rounds of pegloticase dosed every 2 weeks. The markedly reduced APA levels, together with competitive inhibition by free PEG, restored the prolonged circulation of pegloticase to levels observed in APA-naïve animals. In contrast, mice with pegloticase-induced APA eliminated nearly all pegloticase from the circulation within just four hours post-injection. These results support the growing literature demonstrating free PEG may effectively suppress drug-induced APA, which in turn may offer sustained therapeutic benefits without requiring broad immunomodulation. We also showed free PEG effectively blocked the PEGylated protein from binding with cells expressing PEG-specific B cell receptors. It provides a template of how we may be able to tune the interactions and immunogenicity of other polymer-modified therapeutics. A major challenge with engineering materials for drug delivery is their interactions with the immune system. For instance, our body can produce high levels of anti-PEG antibodies (APA). Unfortunately, the field currently lack tools to limit immunostimulation or overcome pre-existing anti-PEG antibodies, without using broad immunosuppression. Here, we showed that simply introducing free PEG into a clinical formulation of PEG-uricase can effectively limit induction of anti-PEG antibodies, and restore their prolonged circulation upon repeated dosing. Our work offers a readily translatable method to safely and effectively restore the use PEG-drugs in patients with PEG-immunity, and provides a template to use unconjugated polymers with low immunogenicity to regulate interactions with the immune system for other polymer-modified therapeutics. [Display omitted] [ABSTRACT FROM AUTHOR]

Abstract The thermal management of insulated-gate bipolar transistor (IGBT) modules is a critical issue in the field of power electronics. According to the minimum thermal resistance principle, this study proposed a rectangular heat pipe radiator with parallel heat flow structure that can be used for cooling two 1700 V/1000 A IGBT modules. The prototypes of typical and novel heat pipe radiators were produced to validate the heat transfer enhancement of the novel structure. Performance evaluation and analysis were numerically and experimentally carried out, and the numerical results agreed well with the experimental data. Parametric studies were performed to analyze the effects of inlet air temperature, air volume, and heat load on the heat dissipation capability. The study found that the novel heat pipe radiator has a good start-up characteristic due to the parallel heat flow structure. Moreover, the performance enhancement of the novel heat pipe radiator is obvious at large heat loads. Experiment results show that the two IGBT modules with 3500 W could be cooled down to 67.8 °C when the air volume is 450 m3 h−1, which is 8.9% lower than that of a typical heat pipe radiator. The proposed novel structure improves thermal performance of the novel heat pipe radiator by significantly decreasing its thermal resistance by 22% in comparison with that of a typical heat pipe radiator. Highlights • A rectangular heat pipe radiator with parallel heat flow structure is proposed. • The energy flow model of heat pipe radiator is developed. • The prototypes of typical and novel heat pipe radiators are produced. • The thermal resistance of novel heat pipe radiator significantly decreases by 22%. [ABSTRACT FROM AUTHOR]

Background Nanoparticle (NP)–based vaccines are attractive immunotherapy tools because of their capability to codeliver antigen and adjuvant to antigen-presenting cells. Their cellular distribution and serum protein interaction ("protein corona") after systemic administration and their effect on the functional properties of NPs is poorly understood. Objectives We analyzed the relevance of the protein corona on cell type–selective uptake of dextran-coated NPs and determined the outcome of vaccination with NPs that codeliver antigen and adjuvant in disease models of allergy. Methods The role of protein corona constituents for cellular binding/uptake of dextran-coated ferrous nanoparticles (DEX-NPs) was analyzed both in vitro and in vivo. DEX-NPs conjugated with the model antigen ovalbumin (OVA) and immunostimulatory CpG-rich oligodeoxynucleotides were administered to monitor the induction of cellular and humoral immune responses. Therapeutic effects of this DEX-NP vaccine in mouse models of OVA-induced anaphylaxis and allergic asthma were assessed. Results DEX-NPs triggered lectin-induced complement activation, yielding deposition of activated complement factor 3 on the DEX-NP surface. In the spleen DEX-NPs targeted predominantly B cells through complement receptors 1 and 2. The DEX-NP vaccine elicited much stronger OVA-specific IgG 2a production than coadministered soluble OVA plus CpG oligodeoxynucleotides. B-cell binding of the DEX-NP vaccine was critical for IgG 2a production. Treatment of OVA-sensitized mice with the DEX-NP vaccine prevented induction of anaphylactic shock and allergic asthma accompanied by IgE inhibition. Conclusions Opsonization of lectin-coated NPs by activated complement components results in selective B-cell targeting. The intrinsic B-cell targeting property of lectin-coated NPs can be exploited for treatment of allergic immune responses. [ABSTRACT FROM AUTHOR]

• The phonon/electron temperature distribution in the μ-TEG leg is analyzed. • Mathematical model of μ-TEG considering interfacial and size effects is developed. • The reduction in ZT from thin film material to micro device is analyzed. • The optimization goals for contact resistivity are explored. • Optimal thermoelectric leg thickness of micro thermoelectric generator is analyzed. Micro thermoelectric generator (μ-TEG) attracts more and more attention due to its small size and high power density. Many two-dimensional thermoelectric materials with high performance have facilitated the development of μ-TEG. However, the performance of μ-TEG fabricated by these great thermoelectric materials is significantly degraded due to size effect, interfacial effects (include contact effect and boundary effect) and structure effect. To accurately assess the performance degradation degree from material to μ-TEG and guide the device fabrication, an experiment-verified mathematical model considering interfacial and size effects is proposed. Firstly, the phonon/electron temperature distribution in thermoelectric leg of μ-TEG is analyzed to investigate the device-level thermoelectric properties of material. Then based on the device-level thermoelectric properties, the actual power generation performance model of μ-TEG is established to conduct the influence analysis of these effects (boundary, size, contact and structure effects) on material and device. Finally, the thermoelectric leg thickness (H te) is optimized to realize optimal power generation. The study results reveal that boundary and size effects weaken the device-level thermoelectric properties, and the reduction trend is more obvious when H te is smaller, especially when H te ≤ 20 μm. The decrease from the material intrinsic figure of merit ((ZT) m) to the device figure of merit ((ZT) D) is owing to the boundary effect, structure effect and contact effect, and the dominant factor of this decrease changes from structure effect (H te ＜7 μm)to contact effect (H te ≥ 7 μm) as H te increases, which points to a main optimization direction for (ZT) D for different H te. As for contact effect, the electrical contact resistivity (r e,c) has a more significant impact on weakening the performance of μ-TEG than thermal contact resistivity (r k,c), and their optimization goals are explored (r e,c ≤ 5.1 × 10−12 Ω·m2, r k,c ≤ 9.3 × 10−8 K·m2/W). At given electrical and thermal contact resistivity, there exists an optimal H te for achieving the optimal power generation (P opt) and a large range of H te for achieving 95% P opt , and the optimal H te increases with increasing electrical and thermal contact resistivity. This study can reduce the processing difficulty and save time and economic costs of μ-TEG fabrication, which can avoid the blind fabrication of μ-TEG. [ABSTRACT FROM AUTHOR]

Despite the success of achieving thermoelectric materials with high figure of merit, precisely evaluating the performance of micro-thermoelectric coolers remains challenging at the microdevice level because of various interfacial effects and device construction. This study develops a method for the effective evaluation of the device-level thermophysical properties capturing various interfacial and size effects, and establishes a three-dimensional numerical model to evaluate the cooling performance of micro-thermoelectric coolers. The model is validated by the reported experimental data. The impact of interaction between boundary and size effects is captured in the investigation of Seebeck coefficient, thermal conductivity and electricity resistivity of the thermoelectric materials at the device-level. Contact resistances are also considered in analyzing the cooling performance. Results indicate that the device-level figure of merit decreases by 5–18.1% with decreased thermoelectric element thickness from 20 μm to 5 μm. The boundary effects considerably weaken the cooling performance of the microdevice, and a higher heat flux corresponds to a greater impact of boundary effects. Cooling temperature increases by 6.1 K due to the boundary effects when heat flux is 300 W/cm 2 , while the temperature difference decreases by 17.1%. Finally, the three-dimensional numerical model is performed to evaluate the cooling performance and optimal working condition of the micro-thermoelectric cooler. At heat flux of 300 W/cm 2 and 200 W/cm 2 , the minimum cold side temperatures of 310.7 K and 287.3 K are predicted to be achieved at 11 μm/20 mA ( H te / I ), 15 μm/16 mA, respectively. [ABSTRACT FROM AUTHOR]

The ability to generate potent immunotherapies locally and transiently for the treatment of cancers is a promising strategy to improve efficacy and decrease off-target toxicities. Here, we explored an alternative approach for the delivery of immunotherapeutic agents, in which we deliver the pDNA of an engineered PD-L1 trap and/or CXCL12 trap to the nucleus of liver hepatocytes via a lipid calcium phosphate nanoparticle. This strategy greatly increased the concentrations of immunotherapeutic agents in the local tissue, allowing the therapy to inhibit the accumulation of immune suppressive cells and liver metastasis. Furthermore, we find that the lipid calcium phosphate nanoparticles containing the pCXCL12 trap resolved the formation of immune suppressive ectopic lymphoid structures, while the pPD-L1 trap promoted T-cell survival and migration into the liver following vaccination against tumor antigens (>180% increase in survival). This approach showed superior efficacy in the treatment of the liver metastasis compared to free protein immunotherapies. This strategy should be considered as an approach to support liver metastasis therapies as well as for future research interested in manipulating the chemokine/cytokine immune factors within the liver. Significance Our approach results in transient liver specific expression of gene immunotherapies with improved efficacy and reduced off-target toxicities over traditional systemically administered immunotherapies. This approach would allow clinicians to manipulate the liver and immune microenvironment to resist cancer invasion, improve organ health, and prolong patient survival. [ABSTRACT FROM AUTHOR]

Net Zero Energy Building (NZEB) has gained increasingly wide attentions over last few years and net zero energy starts to become a new design target of future buildings. This paper presents the first study on thermoelectric technology applications in NZEBs in which both thermoelectric cooling and thermoelectric generation are adopted. Substituting conventional air-conditioning system, the thermoelectric radiant ceiling and the thermoelectric primary air handling unit are adopted to provide thermal comfort and fresh air in NZEBs. Meanwhile, the thermoelectric generation is employed to improve the solar energy generation. Case studies have been performed to investigate the application feasibility of the proposed thermoelectric systems by evaluating the annual energy balance. The study results show that the thermoelectric cooling is able to supply sufficient cooling and heating to ensure thermal comfort. Moreover, the thermoelectric generation significantly improves the annual solar energy generation by 767 kWh (34%) in comparison with conventional photovoltaic system, which eventually turns the targeted office building from a non-zero energy building to a plus energy building. This study provides a new way to apply thermoelectric technology in NZEBs which directly lead to benefits including zero Freon, simple piping, and quiet and reliable operations. [ABSTRACT FROM AUTHOR]

The practical operating conditions of thermoelectric products, such as the input power source and the thermal resistance of hot side heat exchanger, are different from the theoretical study. Thus the equations, which are used to estimate the practical maximum cooling performance just according to the datum in datasheet of commercial thermoelectric module (TEM), are given. The nested loop method is adopted to solve the numerical model. This study provides a method to choose a suitable TEM for thermoelectric product to meet the application requirement. It finds that the minimum cold side temperature increase and the voltage for achieving the minimum cold side temperature step decrease with the increase of thermal resistance of hot side heat exchanger, respectively. The maximum temperature difference increase and the voltage for achieving the maximum temperature difference step increase with the increase of thermal resistance of hot side heat exchanger, respectively. According to the dimension, three kinds of thermoelectric module, bulk TEM, miniature TEM and micro TEM, are studied. The novel scale effect are discovered by comparing these TEMs. It found that the step-change phenomenon become more and more obvious with the decrease of the dimension of thermoelectric module. The influence ratio of thermal resistance of hot side heat exchanger on the maximum cooling performance increases and the influence ratio of input power source decreases from macro to micro, respectively. It forecasts that there exists a critical value for the dimension of thermoelectric module, when the dimension of thermoelectric module is smaller than this critical value, the maximum voltage or current of thermoelectric module is constant and does not change with the thermal resistance of hot side heat exchanger. [ABSTRACT FROM AUTHOR]

Highlights: [•] The scaling effect and supercooling effect affect the performance of MTEM. [•] The voltage for achieving the maximum cooling capacity experiences step decrease. [•] A step-change voltage of MTEM improves the temperature precision of pulse laser. [•] We develop a curve fitting equation to provide more accurate temperature. [ABSTRACT FROM AUTHOR]

Abstract: This paper presents a novel thermoelectric radiant air-conditioning (TE-RAC) system, which employs the thermoelectric modules as radiant panels instead of conventional hydronic panels. The novel radiant system brings a lot of benefits including Freon free, convenient installation, no complex water distribution pipes, quiet and reliable operation, etc. Switching between cooling and heating modes can be easily achieved by reversing the input current. The purpose of this study is to investigate the feasibility and performance of the novel TE-RAC system, including its cooling and heating performances, condensation risk, dynamic thermal response and inertia, and cost-effectiveness. A case study of the TE-RAC system is presented to compare the TE-RAC system with conventional air-conditioning (AC) systems and radiant air-conditioning (RAC) systems in terms of cooling and heating capacities, energy consumption and operation reliability. It is found that the COP of the TE-RAC system could be comparable to conventional RAC systems and AC systems, besides many other benefits in life-cycle performances. [Copyright &y& Elsevier]

• The potential of micro-TEC to mitigate the influence of thermal shock was explored. • A lumped reliability enhancement factor of chip was defined. • Reliability analysis of chip under thermal shock was carried out. • Both the influences of peak temperature and temperature variation were discussed. • Operating scheme of micro-TEC to achieve reliability enhancement was investigated. The highly non-uniform transient power density in modern semiconductor device leads to thermal shocks with high temperature and temperature variation, which causes performance and reliability challenges. This study established a three-dimensional numerical model to investigate the potential of micro-thermoelectric cooler to mitigate the adverse effect of fluctuating hotspot caused by thermal shock. This study also proposed to assess the chip reliability under thermal shock considering both the influences of peak temperature and temperature variation, and a lumped reliability enhancement factor was defined. Furthermore, the operating scheme of micro-thermoelectric cooler to mitigate the adverse effect of thermal shock was investigated. Results show that the micro-thermoelectric cooler can effectively restrain temperature fluctuation of chip undergoing thermal shock. It also found that keeping the micro-thermoelectric cooler working all the time is not necessarily good considering both the influences of peak temperature and temperature variation. The reliability analysis shows that the lumped reliability enhancement factor is greater than 1 as long as the micro-thermoelectric cooler provides cooling capacity for frequency rising to high. However, for frequency reducing to mild, it is beneficial to turn on the micro-thermoelectric cooler when the ratio of influence weight coefficien is larger than 1, otherwise it is better to turn off the micro-thermoelectric cooler. After the micro-thermoelectric cooler was optimized, the critical ratio of influence weight coefficien could be decreased, indicating a wider practicability of the micro-thermoelectric cooler. Meanwhile, the reliability of chip could be further enhanced. For the case of the ratio of influence weight coefficien equaling to 1, when the thermoelectric element thickness increases from 7.5 μm to 30 μm, the maximum lumped reliability enhancement factor of frequency rising to high and frequency reducing to mild could be respectively improved from 1.9 to 5.4, and 1 to 1.9. [ABSTRACT FROM AUTHOR]

Thermoelectric generators (TEGs) with improved conversion efficiency are in great need for low-grade heat recovery. Existing studies primarily optimize the dimensionless figure of merit (ZT) of thermoelectric (TE) materials to improve TEG efficiency. However, TE material with a high ZT cannot guarantee that associated TEG has an optimal performance in practical conditions. To solve this problem, an experiment-verified model is proposed considering the effective temperature difference, optimal matching resistance and contact effect. Sensitivity analysis has been conducted to inversely identify the optimization direction of TE materials at the device level. The impacts of the key physical properties on TEG performance are systematically studied under typical operating conditions. The study results show that reducing lattice thermal conductivity is of more priority than increasing the power factor for improving TEG performance. For power factor improvements of TE materials, Seebeck coefficient optimization is found to be more important than electrical conductivity increase. Besides, the impacts of operating conditions on optimizing TE materials are also investigated. Finally, an optimization process to improve the generation performance of TE materials is proposed, which opens up a new way to lead the development of TE materials from the device and application level. The study results are helpful to effectively improve the power generation performance of TEG through the proposed optimized method of TE materials. • An inverse optimization model of thermoelectric material is proposed. • Figure of merit cannot reflect performance of thermoelectric generator. • Optimization priorities of thermoelectric materials are provided. • It improves optimization of thermoelectric material from device level. [ABSTRACT FROM AUTHOR]

Finned heat pipe radiators are popular as heat dissipation system of electronic components due to high reliability. But the inferior airside heat transfer limits its heat dissipation performance. Thus, the metal foam heat pipe radiator is introduced to solve this issue with metal foam substituting fins. The copper foam with 15 PPI (Pores per inch) is adopted to fabricate prototype to explore the performance enhancement. The thermal and flow characteristics are systematically studied and analyzed through experiments under different air velocity and heating power. The study finds that the introduced metal foam significantly reduces the overall thermal resistance by 25.5% in comparison with traditional finned heat pipe radiator. Meanwhile, it predicts that the decrement of the overall thermal resistance is up to 58% by adopting advanced connecting technology. Furthermore, the trade-off between improvement heat transfer and increased flow resistance were evaluated by the performance evaluation index as the function of Colburn j-factor and friction factor, which provides a direct criterion for its practical application. It finds that the comprehensive performance of metal foam heat pipe radiator is much better than that of traditional finned heat pipe radiator especially when Re < 13000. In addition, the fitting empirical equations of friction factor are given for further theoretical analysis and numerical calculation. • A novel metal foam heat pipe radiator is adopted to enhance airside heat transfer. • The thermal and flow characteristics of MFHPR are experimentally studied. • The thermal resistance of MFHPR reduced by 25.5% under forced convection. • The comprehensive performance of MFHPR is pretty good especially when Re<13000. • The empirical equations of friction factor independent of heating power are given. [ABSTRACT FROM AUTHOR]

Micro-thermoelectric coolers have great potential in the thermal management of highly integrated electronic devices, especially the local cooling. This paper develops a numerical model to explore the influence of Thomson effect on the cooling performance of micro-thermoelectric coolers, capturing interfacial and size effects. The presented model is validated with a commercial micro-thermoelectric cooler. And, analyses are carried out with respect to micro-thermoelectric coolers of different sizes, under different temperatures and cooling loads. The results indicate that a positive Thomson coefficient can improve the cooling capacity, and higher current and thickness correspond to greater impact of Thomson effect. In addition, the decrease of minimum cooling temperature caused by Thomson effect is even more obvious under higher cooling load. The results also show that the influence of Thomson effect on the maximum cooling temperature difference gradually becomes weaker as the cross area to thickness ratio increases. For heat fluxes of 100 W/cm2 and 200 W/cm2, the minimum cooling temperature can be respectively reduced by 2.1 K and 4.1 K, considering Thomson effect. In addition, for the thickness of 10 μm, the increment of maximum cooling temperature difference gradually declines from 2.2 K to 1.1K as the cross area to thickness ratio increases. • A valid model to assess the influence of Thomson effect on micro- TEC s is developed. • The presented model is validated with a commercial micro- TEC. • Analyses are presented under different sizes, temperatures and cooling loads. • Temperature drop caused by Thomson effect is greater under higher cooling load. • Impact of Thomson effect gets weaker as cross area to thickness ratio increases. [ABSTRACT FROM AUTHOR]

Highlights • A model of light emitting - diode with micro - thermoelectric cooler is proposed. • Various interfacial and size effects are considered in the presented model. • Five structures of micro-coolers are designed to reduce the chip temperature. • The impact of interfacial effects on the thermal performance is assessed. • The impact of micro-thermoelectric cooler on the optical performance is analyzed. Abstract Thermoelectric cooler has been widely used in the thermal management of various electronic devices. However, the application of micro - thermoelectric cooler to high power light - emitting diode still needs to be further explored at present. This paper aims to establish a model of high power light - emitting diode package integrated with micro - thermoelectric cooler and explore the performance of this system under various interfacial and size effects. An experiment is conducted to validate the model. Five types of the micro - thermoelectric coolers are designed and integrated to the light - emitting diode package to reduce the localized junction temperature of the light - emitting diode chip. The influence of interfacial effects, thermoelectric element size, and driving power of micro - thermoelectric cooler on the system - level thermal and optical performance is discussed. Results indicate that the micro - thermoelectric cooler with 6 × 6 thermoelectric elements shows the best cooling performance for the driving power of micro - thermoelectric cooler lower than 0.85 W. For thermoelectric cooler with 6 × 6 thermoelectric elements, a minimum chip junction of 95.9 °C, which is 12.3 °C lower than that of the light - emitting diode without micro - thermoelectric cooler, can be achieved. This characteristic can increase the luminous efficacy and lifetime by 12.3% and 50%, respectively. It also found that the electrical boundary resistance plays a more dominant role, compared with the thermal boundary resistance. However, the thermal contact resistance exhibits greater adverse impact than the electrical contact resistance. In addition, a total performance improvement proportion of 25.5% can still be achieved, although the micro - thermoelectric cooler consumes power energy by 22.5% at the driving power of 0.87 W. [ABSTRACT FROM AUTHOR]

• Propose feature-level CNN HVAC FD model interpretation method by ImLRP. • CNN model achieves 96.87% accuracy for classifying seven chiller faults. • Use new metric relevance difference to identify CNN chiller FD criteria and misdiagnosis. • Discuss influencing factors: CNN filter size, LRP parameter, relevance score introduction. Convolutional neural networks (CNNs) have been widely utili sed for fault diagnosis (FD) in building heating, ventilation, and air conditioning (HVAC) systems. Despite achieving high accuracy in many HVAC FD tasks, misdiagnosis still occurs. As a black-box model, the CNN FD model and its diagnostic mechanism and decision-making process are opaque, making it difficult for HVAC operators and managers to trust it. To address this, this study proposes an improved Layer-wise Relevance Propagation (ImLRP) method for interpreting CNN FD models in HVACs.The proposed method addresses the issue of preserving positive/negative information from HVAC inputs by adopting a Softsign activation function in the CNN. The feature-matching issue is addressed by excluding pooling layers from the CNN. ImLRP evaluates the contribution of each neuron in the network to the output decision by assigning a relevance score to each neuron in each layer during the backpropagation of the feedforward transmission process. The relevance score difference, a new metric, is used to obtain the net impact of HVAC faults. The proposed method was validated using RP-1043 chiller fault experiment data, which showed a CNN FD accuracy of 96%. Both correct-diagnosis and misdiagnosis were interpreted at the feature variable level, and the study also discussed the influence of the CNN model parameter, ImLRP parameter, and the relevance score difference on the results. [ABSTRACT FROM AUTHOR]

Precise temperature regulation is a crucial guarantee for many microfluidic analyses. This study presents a linear cooling method of microfluidic chips based on a single TEC, which can achieve synchronous observation of samples. A numerical model was developed and experimentally verified to analyze the temperature responses under different driving current mechanisms of TEC. Based on simulation and experimental analysis, this study proposes to achieve linear cooling based on TEC driven by polynomial function current mechanism. The implementation process is clarified, and the iterative method to obtain the polynomial function current mechanism is provided and elaborated. Using a commercial TEC, the linear cooling of the microfluidic chip from 25.2 °C to −19.7 °C was successfully achieved through both simulation and experiment. The linear cooling rates ranging from 24 °C/min to 41 °C/min with linearity higher than 0.998 were obtained. Moreover, the influencing factors of linear cooling were discussed. It is found that the temperature of the TEC hot side has a significant impact on the linear cooling of the sample cell, while the impact of nitrogen gas temperature is almost negligible. Results also indicate that both the minimum and maximum cooling rates increase as TE-element length increases and TE-element height decreases. [Display omitted] • This work proposes a linear cooling method of microfluidic chip based on TEC. • Linear cooling of microfluidic chip was achieved through simulation and experiment. • Temperature responses of microfluidic chip cooled by TEC were analyzed. • Different driving current mechanisms of TEC were discussed. • Influencing factors and optimization of the linear cooling were discussed. [ABSTRACT FROM AUTHOR]

• The loci (GTA)9, (AT)17, (AT)15, (TA)18, (TTC)21 and (TA)10 are more highly polymorphic than other loci. • The VNTR profile generated a low-density clustering pattern in the counties of Sichuan and Yunnan. • Clusters were observed from the isolates from Hunan and Guizhou provinces at the county levels. • The most predominantly reported SNP was 3K followed by SNP 1D. • We detected the novel SNP 3J that has not yet been reported in China. • Maximum genotype stability was observed in current and long-standing strains. Understanding the nature of Mycobacterium leprae transmission is vital to implement better control strategies for leprosy elimination. The present study expands the knowledge of county-level strain diversity, distribution, and transmission patterns of leprosy in endemic provinces of China. We genetically characterized 290 clinical isolates of M. leprae from four endemic provinces using variable number tandem repeats (VNTR) and single nucleotide polymorphisms (SNPs). Attained genetic profiles and cluster consequences were contrasted with geographical and migration features of leprosy at county levels. Considering the allelic variability of 17 VNTR loci by the discriminatory index, (GTA)9, (AT)17, (AT)15, (TA)18, (TTC)21, and (TA)10 are reported to be more highly polymorphic than other loci. The VNTR profile generated the low-density clustering pattern in the counties of Sichuan and Yunnan, whereas clusters have been observed from the isolates from Huayuan (N = 6), Yongding (N = 3), Zixing (N = 3), Chenxi (N = 2) and Zhongfang (N = 2) counties of Hunan, and Zhijin (N = 3), Anlong (N = 2), Zhenning (N = 2), and Xixiu (N = 2) counties of Guizhou. In some clusters, people's social relations have been observed between villages. From the 290 clinical isolates, the most predominantly reported SNP was 3K (278, 95.8%), followed by SNP 1D (10, 3.4%), which are typically observed to be predominant in China. We also detected the novel SNP 3J (2, 0.8%), which has not yet been reported in China. The clustering pattern of M. leprae indicates the transmission of leprosy still persists at county levels, suggesting that there is a need to implement better approaches for tracing the close contacts of leprosy patients. [ABSTRACT FROM AUTHOR]

The variable refrigerant flow (VRF) system has extremely different energy performance at various operation conditions. Its power consumption is inconsistent even under the steady operation condition. In order to accurately evaluate the VRF system’s dynamic energy performance, this study proposed a data-mining-based method to benchmark and assess its energy uses. The correlation analysis is used for key factors selection and the interquartile range rule is employed to remove outliers of the database. In addition, the power consumption patterns are classified using decision tree (DT) method. The classification results are validated by the ANOVA analysis and post hoc test. Nine energy benchmarks are established based on the classified power consumption patterns. Moreover, an energy consumption rating system is established to provide quantitative assessment on the power consumption of the VRF system. A case study is conducted by comparatively analyzing the energy performance of the VRF system at multiple refrigerant charge fault cases. Results show that both the PLR and OT significantly affected the power consumption of the VRF system. However, the degree to which the refrigerant charge fault affects system power consumption varies with the power consumption patterns. For different patterns, the power consumptions of the VRF system were either lower, higher or similar to each other at various RCLs. Results also suggest that the energy benchmarking process provide reasonable classification criteria, and the grading process provide quantitative assessment on the energy consumption. Therefore, the proposed dynamic energy benchmarks are reliable and reasonable to evaluate the dynamic energy performance of VRF systems. [ABSTRACT FROM AUTHOR]

This paper proposed a universal virtual variable-speed compressor power (VVCP) sensor for VRF system based on 20-coefficient model. Compressor power can be obtained by the VVCP sensor using three input parameters (frequency, condensing temperature and evaporation temperature) which are measured by system itself. The performance of the proposed VVCP sensor is evaluated using experiments data. Experimental conditions include cooling, heating and non-standard refrigerant charge levels. The result shows that the mean square percentage errors (MSPE) are 9.9% under cooling conditions and 7.96% under heating conditions. The MSPE are 9.88% at steady state and 9.75% at dynamic state when the VVCP sensor is applied under nine different refrigerant charge levels. It demonstrated that the proposed VVCP sensor can obtain compressor power under cooling, heating and non-standard refrigerant charge levels, which could be applied to do operational monitoring and fault detection and diagnosis for VRF system at low cost. [ABSTRACT FROM AUTHOR]

Programmed cell death-ligand 1 (PD-L1)-based immune checkpoint blockade therapy using the anti-PD-L1 antibody is effective for a subset of patients with advanced metastatic melanoma but about half of the patients do not respond to the therapy because of the tumor immunosuppressive microenvironment. Immunogenic cell death (ICD) induced by cytotoxins such as doxorubicin (DOX) allows damaged dying tumor cells to release immunostimulatory danger signals to activate dendritic cells (DCs) and T-cells; however, DOX also makes tumor cells upregulate PD-L1 expression and thus deactivate T-cells via the PD-1/PD-L1 pathway. Herein, we show that celastrol (CEL) induced not only strong ICD but also downregulation of PD-L1 expression of tumor cells. Thus, CEL was able to simultaneously activate DCs and T-cells and interrupt the PD-1/PD-L1 pathway between T-cells and tumor cells. In a bilateral tumor model, intratumorally (i.t.) injected celastrol nanoemulsion retaining a high tumor CEL concentration activated the immune system efficiently, which inhibited both the treated tumor and the distant untreated tumor in the mice (i.e., abscopal effect). Thus, this work demonstrates a new and much cost-effective immunotherapy strategy — chemotherapy-induced immunotherapy against melanoma without the need for expensive immune-checkpoint inhibitors. [ABSTRACT FROM AUTHOR]