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Sustainable development in the building sector requires the integration of energy efficiency and renewable energy utilization in buildings. In recent years, the concept of net zero energy buildings (NZEBs) has become a potential plausible solution to improve efficiency and reduce energy consumption in buildings. To achieve an NZEB goal, building systems and design strategies must be integrated and optimized based on local climatic conditions. This paper provides a comprehensive review of NZEBs and their current development in hot and humid regions. Through investigating 34 NZEB cases around the world, this study summarized NZEB key design strategies, technology choices and energy performance. The study found that passive design and technologies such as daylighting and natural ventilation are often adopted for NZEBs in hot and humid climates, together with other energy efficient and renewable energy technologies. Most NZEB cases demonstrated site annual energy consumption intensity less than 100 kW-hours (kWh) per square meter of floor space, and some buildings even achieved “net-positive energy” (that is, they generate more energy locally than they consume). However, the analysis also shows that not all NZEBs are energy efficient buildings, and buildings with ample renewable energy adoption can still achieve NZEB status even with high energy use intensity. This paper provides in-depth case-study-driven analysis to evaluate NZEB energy performance and summarize best practices for high performance NZEBs. This review provides critical technical information as well as policy recommendations for net zero energy building development in hot and humid climates.

Aiyun Yang,1 Tao Wen,2 Boya Hao,2 Yiling Meng,2 Xue Zhang,2 Tian Wang,2 Jie Meng,2 Jian Liu,2 Jianhua Wang,1 Haiyan Xu2 1Beijing Municipal Key Laboratory of Child Development and Nutriomics, Department of Translational Medicine, Capital Institute of Pediatrics, Beijing, People’s Republic of China; 2Institute of Basic Medical Sciences Chinese Academy of Medical Sciences, School of Basic Medicine Peking Union Medical College, Beijing, People’s Republic of ChinaCorrespondence: Haiyan Xu; Tao Wen, Institute of Basic Medical Sciences Chinese Academy of Medical Sciences, School of Basic Medicine Peking Union Medical College, 5 Dong Dan San Tiao, Dongcheng District, Beijing, People’s Republic of China, Tel +86 106 915 6437, Email xuhy@pumc.edu.cn; went@ibms.pumc.edu.cnPurpose: Pt-based nanostructures are one of the promising nanomaterials for being used in catalysts, sensors, and therapeutics. However, their impacts on the health and biological systems are not adequately understood yet.Methods: In this work, nanorods composed of ultrasmall platinum (Pt) nanoparticles deposited on the surface and gold nanorod as the core (Au@Pt NRs) were synthesized, and the distribution and toxic effects of Au@Pt NRs were investigated in C57BL/6 mice with intravenous injection by using atomic absorption spectroscopy (AAS), transmission electron microscope (TEM), hematoxylin-eosin (HE) staining and blood cell analyzer.Results: At the time point of Day 1, Day 8 and Day 16 post injection of Au@Pt NRs (6 mg/kg of Pt atom), Au@Pt NRs were mainly accumulated in the liver and spleen. The energy dispersive spectrometer mapping images showed Au@Pt NRs experienced quick corrosion and Au released faster than Pt in the physiological environments. The catalase (CAT) activity in tissues increased slightly in the early stage of the Au@Pt NRs exposure and went down to the normal level. With HE staining, inflammatory cells infiltration could be seen in the tissues, while no significant influences were detected on the blood biochemistry and the function of liver and kidney.Conclusion: In conclusion, intravenously injected Au@Pt NRs mainly distributed in the liver and spleen with comparable levels, and did not exert any significant toxic effects on the organs’ function within two weeks; meanwhile, Au@Pt NRs were able to degrade, which indicated acceptable safety to the mice and potentials of biomedical application.Keywords: noble metal nanoparticles, distribution, toxicity, oxidative stress, intravenous injection

This study investigated the effect of a mixed obstacle layout on the deflagration mechanism of propane--air premixed gases. Most previous studies focused on a single type of obstacle, changing the shape and number of the obstacles to observe the effect on the flame deflagration characteristics. However, in real explosion accident sites, obstacles are often a mixture of different types. Little literature exists on the deflagration characteristics of hybrid barriers in semiconfined spaces. In this paper, the deflagration characteristics of propane-air premixed gas with a mixed structure of hurdles and square obstacles was studied. First, the effectiveness of numerical simulations was demonstrated by comparing experimental and large eddy simulation (LES) results for the flame dynamics with a single flat plate obstacle. Based on this, the flame behavior for different layouts of square obstacles in a mixed obstacle configuration was further simulated using the large eddy simulation method, focusing on the flame behavior, overpressure characteristics, and flow field structure in the vicinity of the obstacle. The results showed that a mixed obstacle promoted flame evolution more than a single obstacle when the square obstacle was within a critical distance from the ignition source location at the same moment in time. When the flame front crossed the first hurdle-type obstacle, the flame pattern spread in a "cat's paw" pattern to the unburned portion of the tube. In addition, the increased distance of the square obstacle from the ignition source did not allow the peak overpressure and the peak rate of overpressure rise to show a positive feedback mechanism. Finally, the strength of the vorticity in the flow field was positively correlated with the distance of the square obstacle from the ignition source. The results of study provide theoretical for the prevention of explosions. [ABSTRACT FROM AUTHOR]

Disrupted in schizophrenia 1 (DISC1) is a multi-functional scaffolding protein that has been associated with neuropsychiatric disease. The role of DISC1 is to assemble protein complexes that promote neural development and signaling, hence tight control of the concentration of cellular DISC1 in neurons is vital to brain function. Using structural and biochemical techniques, we show for we believe the first time that not only is DISC1 turnover elicited by the ubiquitin proteasome system (UPS) but that it is orchestrated by the F-Box protein, FBXW7. We present the structure of FBXW7 bound to the DISC1 phosphodegron motif and exploit this information to prove that disruption of the FBXW7-DISC1 complex results in a stabilization of DISC1. This action can counteract DISC1 deficiencies observed in neural progenitor cells derived from induced pluripotent stem cells from schizophrenia patients with a DISC1 frameshift mutation. Thus manipulation of DISC1 levels via the UPS may provide a novel method to explore DISC1 function.

The bullet shape is critical in efficient bullet design because it affects the lift and drag forces. This paper proposes a new bullet shape with a logarithmic curve and analyzes the lift and drag coefficients of bullets with different curves under different angles of attack. The results are compared with a bullet whose shape is described by the power law curve. Fluent simulations demonstrate that the optimal power exponent values are 0.65, 0.6, and 0.65 for the bullet with the power law curve and 1.3, 1, and 1 for the bullet with the logarithmic curve at 0°, 30°, and 40° angles of attack, respectively. At a 0° angle of attack, the lift coefficient of the logarithmic curve is the largest. The lift force of the bullet with the logarithmic curve is 129.4% higher than that with the von Karman curve. The drag coefficient is the largest for the bullet with the rectilinear curve; it is 1.30% larger than that of the bullet with the logarithmic curve. At 30° and 40° angles of attack, the lift coefficient of the bullet with the power law curve is larger. The difference in the lift coefficients between the two angles of attack is 18.47%. The bullet's drag coefficient is the largest for the logarithmic curve, and the difference in the drag coefficients between the two angles of attack is 18.59%. [ABSTRACT FROM AUTHOR]

Researchers recently synthesized a new orthorhombic allotrope of silicon, namely Cmcm Si24. This work studied the effect of one vacancy for Cmcm Si24 on structural, electronic, and mechanical anisotropy properties by the first principle calculation. The lattice parameters of Cmcm Si24:V are the same as Cmcm Si24, but the density of Cmcm Si24:V is larger than that of Cmcm Si24. Moreover, the values of elastic moduli for Cmcm Si24:V are smaller than for Cmcm Si24. The Cmcm Si24:V has mechanical stability and anisotropy and has lower formation energy than diamond-Si. The analysis of the band structures shows that Cmcm Si24 is an indirect band gap material, and the value of the band gap is 1.08 eV. In particular, electronic band structures of Cmcm Si24:V exhibit metallic characteristics. Furthermore, the electron localization function indicated strong covalent silicon--silicon bonds in Cmcm Si24 and Cmcm Si24:V. In addition, the effective mass of electrons and holes of Cmcm Si24 is smaller than that of diamond-Si along the a direction, and larger than that along the b and c directions. Finally, the X-ray diffraction patterns for Cmcm Si24 and Cmcm Si24:V are very close after 13:84°. [ABSTRACT FROM AUTHOR]

In the field of hydrogen safety and combustion, the effect of obstacles on hydrogen deflagration is a topic of general interest to scholars. In previous studies, scholars usually used uniform obstacles under various operating conditions and obtained conclusions by changing their number and positions. However, in practice, the shapes of obstacles at an accident site are often not the same and regular. In this paper, a series of obstacles with variations in length were investigated, and the effects of the obstacles on hydrogen deflagration under different working conditions were analyzed. The configuration of the obstacles with gradually increasing lengths amplified the vortices in the flow field so that the propagation direction of the flame front surface was reversed after passing three obstacles. The variations in the lengths of the obstacles had a significant stretching effect on the propagation of the flame and a considerable acceleration effect on the propagation speed of the flame. The main reason for the acceleration was the rapid propagation of the flame achieved by the vortex when rupture occurred. The change in the pressure gradient that occurred at the center of rotation caused rapid movement of the combustion gases, which ultimately led to an increase in the flame propagation speed. A configuration with gradually increasing lengths of the obstacles promoted the overpressure. A configuration with gradually decreasing lengths of the obstacles suppressed the overpressure. The reason for the formation of the local high-pressure area was that unburned gas was accumulated there by pressure waves and the obstacle walls, and then the thermal expansion formed a high pressure. The Rayleigh-Taylor and Kelvin-Helmholtz instabilities caused the overpressure to rise further. The results can provide a theoretical basis for hydrogen transportation, storage, and safety. [ABSTRACT FROM AUTHOR]

The formation of supercavitation after a high-speed projectile enters water has a decisive impact on the underwater ballistic and penetration of the projectile. In this study, Ansysfluent19.0 simulation software is used to study water entry of a chosen projectile at velocities of 300, 400, 500, and 600 m/s. The underwater cavitation characteristics, trajectories, and flow-field characteristics are analyzed for a 5.8-mm caliber conical flat head projectile, as well as for t wo other projectiles of the same caliber and different head shapes -- conical cone head and elliptical flat head -- entering water vertically at the same velocities. The attenuation rate of water entry velocity increases with the increase of velocity. Within first 3ms, the velocity attenuation rate of the conical flat-head projectile with a water entry velocity of 600m / s is 55.6 %, while the velocity attenuation rate of the projectile with a water entry velocity of 300m / s is only 16.3 % within 3ms. Among the head shapes considered, the conical flat head projectile is the most stable for vertical water entry. The stability of an elliptical flat head projectile is worse, and the trajectory stability of a conical cone head projectile is still worse. [ABSTRACT FROM AUTHOR]

Song Gao,1,* Jianfeng Li,2 Chen Jiang,2 Bo Hong,3 Bing Hao4,* 1Department of Clinical Laboratory, The Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, 2Key Laboratory of Smart Drug Delivery, Ministry of Education, Department of Pharmaceutics, School of Pharmacy, Fudan University, Shanghai, 3Department of Pathology, The Second Affiliated Hospital, 4Key Laboratory of Combined Multi-Organ Transplantation, Ministry of Public Health, First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, People’s Republic of China *These authors contributed equally to this work Abstract: A gene drug delivery system for glioma therapy based on transferrin (Tf)-modified polyamidoamine dendrimer (PAMAM) was prepared. Gene drug, tumor necrosis factor-related apoptosis-inducing ligand (hTRAIL)-encoding plasmid open reading frame (pORF-hTRAIL, Trail), was condensed by Tf-modified PAMAM to form nanoparticles (NPs). PAMAM-PEG-Tf/DNA NPs showed higher cellular uptake, in vitro gene expression, and cytotoxicity than PAMAM-PEG/DNA NPs in C6 cells. The in vivo targeting efficacy of NPs was visualized by ex vivo fluorescence imaging. Tf-modified NPs showed obvious glioma-targeting trend. Plasmid encoding green fluorescence protein (GFP) was also condensed by modified or unmodified PAMAM to evaluate the in vivo gene expression level. The PAMAM-PEG-Tf/plasmid encoding enhanced green fluorescence protein (pEGFP) NPs exhibited higher GFP expression level than PAMAM-PEG/pEGFP NPs. TUNEL assay revealed that Tf-modified NPs could induce much more tumor apoptosis. The median survival time of PAMAM-PEG-Tf/Trail-treated rats (28.5 days) was longer than that of rats treated with PAMAM-PEG/Trail (25.5 days), temozolomide (24.5 days), PAMAM-PEG-Tf/pEGFP (19 days), or saline (17 days). The therapeutic effect was further confirmed by magnetic resonance imaging. This study demonstrated that targeting gene delivery system had potential application for the treatment of glioma. Keywords: gene therapy, BBB, hTRAIL, PAMAM, C6 glioma

There has been much recent research on high-speed projectiles entering water, but research on the selection of the material for supercavitating projectiles is limited. Some important properties of such projectiles--mass and moment of inertia, for example--are related to the material density, so the projectile's density has an important effect on the performance of the supercavitating projectile. This study, using Ansys fluent 19.0 simulation software, studied the details of water entry of four high-speed projectiles of the same shape but made of different materials: aluminum (2.7 g/cm3), steel (7.85 g/cm3), brass (8.5 g/cm3), and tungsten alloy (17.5 g/cm3). The cavity shape, ballistic and hydrodynamic characteristics, and cavity flow field characteristics of projectiles with different densities were analyzed for a water-entry velocity of 600 m/s. The results show that within 3 ms, the velocity of a projectile with a density of 2.7 g/cm3 drops to 171.8 m/s, and the velocity of a projectile with a density of 17.5 g/cm3 drops to 433.1 m/s. Increasing the density of the projectile evidently reduces the deceleration of the projectile. The drag coefficient depends, primarily on the size and shape of the projectile, only slightly on its density. Just after water-entry time, the higher the density of the projectile, the faster the expansion of its cavity wall. As time after water entry increases, the expansion velocity of the cavity wall gradually decreases. The simulation results show that the projectile head experiences the greatest pressure, producing a sharp peak, at the moment when it touches the water surface. During the flow stabilization phase, the lower the density of the projectile, the lower the pressure on the head of the projectile. The results of this study will help to guide the selection of material for supercavitating projectiles. [ABSTRACT FROM AUTHOR]

OBJECTIVE: The aim of our study was to elucidate the clinical characteristics of alcoholic-hyperlipidemic etiologically complex acute pancreatitis. PATIENTS AND METHODS: We reviewed complete data from 233 patients with acute pancreatitis treated in our hospital during the period January 2017-January 2022. They were divided into three groups according to etiology: alcoholic acute pancreatitis (AAP), hyperlipidemic acute pancreatitis (HLAP), and alcoholic-hyperlipidemic acute pancreatitis (AHAP). General clinical data, co-morbidities, laboratory results, imaging data, and disease severity were analyzed and compared between groups. RESULTS: The proportion of male individuals in the AHAP group was significantly higher than that in the HLAP group (p<0.001). Age of onset was lower and the number of cases with antibiotic use was higher in the AHAP group than in the AAP group (p<0.05). Additionally, the average alcohol intake each time and weekly alcohol intake were also higher in the AHAP group than in the AAP group (p<0.05). Comparison of disease severity (moderate and severe acute pancreatitis, severe acute pancreatitis, and modified computed tomography severity index score) revealed the disease condition to be more severe in the AHAP group than in the AAP and HLAP groups (p<0.05). Accordingly, patients in the AHAP group had longer hospital stays than those in the other two groups (p<0.05). There were no significant differences in alcohol consumption, severity, or length of hospital stay in the AHAP group (p>0.05). CONCLUSIONS: The clinical characteristics of patients in the AHAP, AAP and HLAP groups were different, and the patients in the AHAP group were more likely to have a moderate to severe disease course, with longer hospital stay. As a new AP classification concept, AHAP would offer high significance for diagnosis, treatment, and prognosis. [ABSTRACT FROM AUTHOR]