Ex vivo biomechanical investigations of combined extra- and intracapsular stabilization in canines with cranial cruciate ligament deficiency.

Intracapsular reconstruction (ICR) has long been recommended as a treatment for cranial cruciate ligament deficiency (CCLD) in dogs, but it has fallen out of favor due to its inferior long-term functional outcomes. These outcomes may be attributed to the poor stiffness and strength of the graft in the early period before ligamentization is completed. Additional placement of extracapsular sutures to mechanically protect the graft during the ligamentization process may be a viable method to address this problem. However, the biomechanical effect of this combined surgical approach remains unknown. This study aimed to evaluate the 3D kinematics of the CCLD stifle in dogs in response to ICR and combined extra- and intracapsular reconstruction (CEICR). Twelve hindlimbs were collected from nine cadavers of mature dogs. The limbs were tested using a custom-made testing apparatus that reproduces their sagittal plane kinematics during the stance phase. Four statuses of stifle joints were tested, namely, (a) cranial cruciate ligament (CCL) intact; (b) CCLD; (c) CCLD stifle stabilized by CEICR; and (d) CCLD stifle stabilized by ICR only. Three-dimensional stifle kinematics at the 5 instances of the stance phase were measured with an optoelectronic system. The results showed that ICR marginally corrects the increased adduction, internal rotation, and caudodistal stifle joint center displacement that occur as a result of CCLD. CEICR led to better restoration of the stifle kinematics, especially with respect to the internal rotation and cranial translation stabilities. Furthermore, CEICR only resulted in minor excessive restraints on other motion components. The findings indicated that the additional lateral fabellotibial suture offers immediate stability to the stifle, consequently lowering the risk of graft over-elongation in the short term postoperatively. Considering the propensity for the extracapsular suture to degrade over time, further in vivo studies are warranted to explore the long-term effects of the CEICR procedure.

The Numerical Simulations and Experimental Study of an 8-Inch SiC Single Crystal with Reduced BPD Density.

The basal plane dislocation (BPD) density is one of the most important defects affecting the application of SiC wafers. In this study, numerical simulations and corresponding experiments were conducted to investigate the influence of cooling processes, seed-bonding methods, and graphite crucible materials on the BPD density in an 8-inch N-type 4H-SiC single crystal grown by the physical vapor transport (PVT) method. The results showed that the BPD density could be effectively reduced by increasing the cooling rate, optimizing the seed-bonding method, and adopting a graphite crucible with a similar coefficient of thermal expansion as the SiC single crystal. The BPD density in the experiments showed that a high cooling rate reduced the BPD density from 4689 cm-2 to 2925 cm-2; optimization of the seed-bonding method decreased the BPD density to 1560 cm-2. The BPD density was further reduced to 704 cm-2 through the adoption of a graphite crucible with a smaller thermal expansion coefficient.

Ex vivo biomechanical evaluation of extracapsular stabilization with quasi-isometric points in canine cranial cruciate ligament-deficient stifles.

BACKGROUND: Cranial cruciate ligament (CCL) disease is one of the most common causes of lameness in dogs. The extracapsular stabilization (ECS) utilizing bone anchors and monofilament nylon leader was an alternative treatment for CCL-deficient (CCLD) dogs. However, the biomechanical response of the canine stifle to such a surgical repair strategy in conjunction with the use of recently reported quasi-isometric anchoring points remains unclear. The objectives of the study were to evaluate the mobility and stability of CCL-intact, CCLD, and CCLD stifles repaired with ECS at two different pairs of quasi-isometric points (quasi-IPs). METHODS: Twelve stifle specimens from 7 dogs underwent mobility and stability tests under 4 different conditions, namely, CCL-intact, CCLD, and ECS-repaired at 2 different pairs of quasi-IPs (referred to as ECS-IP1 and ECS-IP2). The mobility tests evaluated 6 degrees-of-freedom stifle kinematics during flexion and extension. The stability tests involved cranial drawer and tibial internal rotation (IR) tests at various stifle opening angles and quantifying the cranial tibial translation (CTT) and tibial IR angles under constantly applied loadings. RESULTS: The ECS repaired at quasi-IPs was shown to restore cranial instability of the stifles with averaged CTT magnitudes < 1.4 mm. During the tibial IR test, the ECS treatments resulted in significantly less tibial IR compared to those in intact CCL stifles. The mobility tests showed similar results. CONCLUSION: The 2 chosen pairs of quasi-IPs were shown to effectively correct the excessive CTT caused by CCLD stifles, whereas the excessive tibial external rotation in comparison to those of intact stifles should be considered for its subsequent influence on joint alignment and the contact pressure applied to the stifle joint.

Liver Lipidomics Analysis Revealed the Novel Ameliorative Mechanisms of L-Carnitine on High-Fat Diet-Induced NAFLD Mice.

The beneficial effects of L-carnitine on non-alcoholic fatty liver disease (NAFLD) were revealed in previous reports. However, the underlying mechanisms remain unclear. In this study, we established a high fat diet (HFD)-induced NAFLD mice model and systematically explored the effects and mechanisms of dietary L-carnitine supplementation (0.2% to 4%) on NAFLD. A lipidomics approach was conducted to identify specific lipid species involved in the ameliorative roles of L-carnitine in NAFLD. Compared with a normal control group, the body weight, liver weight, concentrations of TG in the liver and serum AST and ALT levels were dramatically increased by HFD feeding (p < 0.05), accompanied with obvious liver damage and the activation of the hepatic TLR4/NF-κB/NLRP3 inflammatory pathway. L-carnitine treatment significantly improved these phenomena and exhibited a clear dose-response relationship. The results of a liver lipidomics analysis showed that a total of 12 classes and 145 lipid species were identified in the livers. Serious disorders in lipid profiles were noticed in the livers of the HFD-fed mice, such as an increased relative abundance of TG and a decreased relative abundance of PC, PE, PI, LPC, LPE, Cer and SM (p < 0.05). The relative contents of PC and PI were significantly increased and that of DG were decreased after the 4% L-carnitine intervention (p < 0.05). Moreover, we identified 47 important differential lipid species that notably separated the experimental groups based on VIP ≥ 1 and p < 0.05. The results of a pathway analysis showed that L-carnitine inhibited the glycerolipid metabolism pathway and activated the pathways of alpha-linolenic acid metabolism, glycerophospholipid metabolism, sphingolipid metabolism and Glycosylphosphatidylinositol (GPI)-anchor biosynthesis. This study provides novel insights into the mechanisms of L-carnitine in attenuating NAFLD.

Lanthanide Single-molecule Magnets: Synthetic Strategy, Structures, Properties and Recent Advances.

Single-molecule magnets (SMMs) show wide potential applications in the field of ultrahigh-density storage materials, quantum computing, spintronics, and so on. Lanthanide (Ln) SMMs, as an important category of SMMs, open up a promising prospect due to their large magnetic moments and huge magnetic anisotropy. However, the construction of high performance for Ln SMMs remains an enormous challenge. Although remarkable advances are focused on the topic of Ln SMMs, the research on Ln SMMs with different nuclear numbers is still deficient. Therefore, this review summarizes the design strategies for the construction of Ln SMMs, as well as the metal skeleton types. Furthermore, we collect reported Ln SMMs with mononuclearity, dinuclearity, and multinuclearity (three or more Ln spin centers) and the SMM properties including energy barrier (Ueff ) and pre-exponential factor (τ0 ) are described. Finally, Ln SMMs with low-nuclearity SMMs, especially for single-ion magnets (SIMs), are highlighted to understand the correlations between structures and magnetic behavior of the detail SMM properties are described. We expect the review can shed light on the future developments of high-performance Ln SMMs.

Dietary supplementation of L-carnitine ameliorates metabolic syndrome independent of trimethylamine N-oxide produced by gut microbes in high-fat diet-induced obese mice.

Metabolic syndrome (MS) is a collection of risk factors of serious metabolic diseases. L-Carnitine is an essential nutrient for human health, and the precursor of trimethylamine N-oxide (TMAO). Previous studies have shown that the effect of L-carnitine on MS is controversial, and no studies have considered the role of gut microbiota in the regulation of MS by L-carnitine. In the present study, we established a high-fat diet (HFD)-induced obese mice model and systematically explored the effect of a broad range of dietary L-carnitine concentrations (0.2% to 4%) on the major components of MS. The results show that L-carnitine (0.5%-4%) reduced HFD-caused body-weight gain, visceral adipose tissue, glucose intolerance, hyperglycemia, HOMA-IR index, hyperlipemia, hypertension, and hyperuricemia. The elevation in the concentrations of IL-6, IL-1ß, and TNF-α and decline in IL-10 in both serum and adipose tissue were also attenuated by L-carnitine. Furthermore, dietary L-carnitine increased the serum levels of TMAO produced by gut microbes. High-dose L-carnitine (2% and 4%), but not low-dose L-carnitine (0.2%-1%), notably modulated the composition of gut microbiota and partially attenuated HFD-induced gut microbiota dysbiosis. These results suggest that the ameliorative effect of L-carnitine on MS was independent of TMAO production and only partially related to the regulation of gut microbiota. This study provides crucial evidence for the utilization of L-carnitine as a safe and effective supplement for MS.

Cordyceps guangdongensis lipid-lowering formula alleviates fat and lipid accumulation by modulating gut microbiota and short-chain fatty acids in high-fat diet mice.

Obesity has caused serious health and economic problems in the world. Cordyceps guangdongensis is a high-value macrofungus with broad application potential in the food and bio-medicine industry. This current study aimed to estimate the role of C. guangdongensis lipid-lowering compound formula (CGLC) in regulating fat and lipid accumulation, gut microbiota balance, short-chain fatty acid (SCFA) contents, and expression levels of genes involved in fat and lipid metabolism in high-fat diet (HFD) mice. The results showed that CGLC intervention markedly reduced body weights and fat accumulation in HFD mice, improved glucose tolerance and blood lipid levels, and decreased lipid droplet accumulation and fat vacuole levels in the liver. CGLC decreased the ratio of Firmicutes and Bacteroidetes and increased the relative abundances of Bacteroides (B. acidifaciens) and Bifidobacterium (B. pseudolongum). In addition, CGLC treatment significantly promoted the production of SCFAs and regulated the relative expression levels of genes involved in fat and lipid metabolism in liver. Association analysis showed that several species of Bacteroides and most of SCFAs were significantly associated with serum lipid indicators. These results suggested that CGLC is a novel candidate formulation for treating obesity and non-alcohol fatty liver by regulating gut microbiota, SCFAs, and genes involved in fat and lipid metabolism.

Three Gd-based magnetic refrigerant materials with high magnetic entropy: From di-nuclearity to hexa-nuclearity to octa-nuclearity.

Magnetocaloric effect (MCE) is one of the most promising features of molecular-based magnetic materials. We reported three Gd-based magnetic refrigerant materials, namely, Gd2(L)(NO3)(H2O)‧CH3CN‧H2O (1, H2L = (Z)-N-[(1E)-(2-hydroxy-3-methphenyl)methylidene]pyrazine-2-carbohydrazonic acid), {Gd6(L)6(CO3)2(CH3OH)2(H2O)3Cl}Cl‧4CH3CN (2), and Gd8(L)8(CO3)4(H2O)8‧2H2O (3). Complex 1 contains two GdIII ions linked by two η 2:η 1:η 1:η 1:µ 2-L2- ligands, which are seven-coordinated in a capped trigonal prism, and complex 2 possesses six GdIII ions, contributing to a triangular prism configuration. For complex 3, eight GdIII ions form a distorted cube arrangement. Moreover, the large values of magnetic entropy in the three complexes prove to be excellent candidates as cryogenic magnetic coolants.

Interviewer Error Within the Face-to-Face Food Frequency Questionnaire in Large Multisite Epidemiologic Studies.

Interviewer error has long been recognized in face-to-face surveys, but little is known about interviewer error within face-to-face food frequency questionnaires, particularly in large multisite epidemiologic studies. Using dietary data from the China Multi-Ethnic Cohort (2018-2019), in which all field interviews were audio recorded, we identified a potentially error-prone sample by outlier detection and further examined the interviewer errors by reviewing these error-prone interviews. Among 174,012 questions for 5,025 error-prone interviews, 13,855 (7.96%) questions were identified with interviewer error, which mainly came from falsification (37.53%), coding error (31.71%), and reading deviation (30.76%). We found that 98.29% of interviewers and 73.71% of respondents had at least 1 error, and half of the errors could be attributed to 21.94% of interviewers or to 13.77% of respondents. Higher error risk was observed in complicated questions, such as questions assessing food quantification or referring to seasonally supplied food groups. After correcting the errors, the means and standard deviations of estimated food intakes all decreased. These findings suggested that interviewer error should not be ignored within face-to-face food frequency questionnaires and that more efforts are needed to monitor error-prone interviewers and respondents and reduce survey burdens in questionnaire design.

A Photosensitizer Discretely Loaded Nanoaggregate with Robust Photodynamic Effect for Local Treatment Triggers Systemic Antitumor Responses.

Photodynamic therapy (PDT), is a rising star for suppression of in situ and metastatic tumors, yet it is impeded by low ROS production and off-target phototoxicity. Herein, an aggregation degree editing strategy, inspired by gene editing, was accomplished by the coordination of an aggregation degree editor, p(MEO2MA160-co-OEGMA40)-b-pSS30 [POEGS; MEO2MA = 2-(2-methoxyethoxy)ethyl methacrylate, OEGMA = oligo(ethylene glycol) methacrylate; pSS = poly(styrene sulfonate)] and indocyanine green (ICG) to nontoxic Mg2+, forming an ICG discretely loaded nanoaggregate (ICG-DNA). Optimization of the ICG aggregation degree [POEGS/ICG (P/I) = 6.55] was achieved by tuning the P/I ratio, alleviating aggregation-caused-quenching (ACQ) and photobleaching concurrently. The process boosts the PDT efficacy, spurring robust immunogenic cell death (ICD) and systemic antitumor immunity against primary and metastatic immunogenic "cold" 4T1 tumors via intratumoral administration. Moreover, the temperature-sensitive phase-transition property facilitates intratumoral long-term retention of ICG-DNA, reducing undesired phototoxicity to normal tissues; meanwhile, the photothermal-induced tumor oxygenation further leads to an augmented PDT outcome. Thus, this simple strategy improves PDT efficacy, boosting the singlet oxygen quantum yield (ΦΔ)-dependent ICD effect and systemic antitumor responses via local treatment.

Biosynthetic Pathway and the Potential Role of Melatonin at Different Abiotic Stressors and Developmental Stages in Tolypocladium guangdongense.

Melatonin, a bioactive compound and an important signaling molecule produced in plants and animals, is involved in many biological processes. However, its function and synthetic pathways in fungi are poorly understood. Here, the samples from Tolypocladium guangdongense, a highly valued edible fungus with functional food properties, were collected under different experimental conditions to quantify the levels of melatonin and its intermediates. The results showed that the intracellular melatonin content was markedly improved by Congo red (CR), cold, and heat stresses; the levels of intracellular melatonin and its intermediates increased at the primordial (P) and fruiting body (FB) stages. However, the levels of most intermediates exhibited a notable decrease under CR stress. Several genes related to melatonin synthesis, excluding AADC (aromatic-L-amino-acid decarboxylase), were markedly upregulated at an early stage of CR stress but downregulated later. Compared to the mycelial stage, those genes were significantly upregulated at the P and FB stages. Additionally, exogenous melatonin promoted resistance to several abiotic stressors and P formation in T. guangdongense. This study is the first to report melatonin biosynthesis pathway in macro-fungi. Our results should help in studying the diversity of melatonin function and melatonin-synthesis pathways and provide a new viewpoint for melatonin applications in the edible-medicinal fungus.

Bio-based visual optical pressure-responsive sensor.

A bio-based pressure-responsive sensor with adjustable structural color is prepared by combining aerogel skeleton of cellulose nanocrystals (CNCs)/poly(ethylene glycol) (PEG) obtained via the ice-templating method with flexible polyacrylamide (PAAM) elastomer. The white aerogel is composed of consecutive ribbons, demonstrating chiral nematic structure. These ribbons are rearranged to be vertical to the force direction, leading to immediate appearance of the structural color when the 3D aerogel transforms to a 2D plane. Helical pitches are regulated by the PEG content that the wavelength of structural color covers up to 178 nm. There is an excellent linear correlation between pressure and transmittance of reflectance peak, and the sensitivity to pressure can be regulated by changing solid content of PAAM. Furthermore, the pressure-responsive color is still vivid after 16 cycles of compression. This flexible material with pressure-responsive structural color is promising in sensing, intelligent display, information transmission, and etc.

Identification of microRNA-like RNAs in Cordyceps guangdongensis and their expression profile under differential developmental stages.

Cordyceps guangdongensis is a well-known fungus with high nutritional and medicinal value. The metabolite profile of C. guangdongensis is similar to that of Ophiocordyceps sinensis. In plants and animals, microRNAs play important roles in regulating gene expression at the post-transcriptional level. MicroRNA-like RNAs (milRNAs) have been documented in several macro-fungi. To comprehensively investigate the milRNAs in C. guangdongensis, three small RNA libraries from the differentially developmental stages were constructed. Twenty-six conserved milRNAs were identified, and 19 novel milRNA candidates were predicted. Among them, 20 milRNAs were differentially expressed across the developmental processes, and 12 milRNAs were verified using stem-loop quantitative real-time reverse transcription polymerase chain reaction. In addition, the potential target genes of milRNA were predicted to be involved in the development of fruiting bodies and metabolite biosynthesis. This study is the first to report the milRNAs of C. guangdongensis, and provides important insights into studies of milRNA regulation pathways in ascomycete fungi.

Orchestration of lincRNA-p21 and miR-155 in Modulating the Adaptive Dynamics of HIF-1α.

Hypoxia-inducible factor-1 (HIF-1) is the key regulator of cellular adaptive response to hypoxia. Accumulating evidence shows that HIF-1 induces some non-coding RNAs (ncRNAs) including lncRNAs and miRNAs to modulate its own activity, enclosing several feedback loops. How the two classes of ncRNAs are orchestrated in the HIF-1-dependent adaptive response to hypoxia is poorly understood. By selecting lincRNA-p21 and miR-155 as the representatives, we develop an integrated model of the HIF-1 network comprising interlinked positive and negative feedback loops to clarify the interplay between the two ncRNAs in the hypoxic response. By numerical simulations, we find that coordination of lincRNA-p21 and miR-155 shapes the adaptive dynamics of HIF-1α: lincRNA-p21 induction in the early phase stimulates the upregulation of HIF-1α via stabilizing it, while miR-155 induction in the late phase promotes the recovery of HIF-1α via enhancing the degradation of its mRNA. Moreover, HIF-1α-induced PHD2 plays an auxiliary role in the decline of HIF-1α. In addition, lincRNA-p21 and miR-155 modulate each other via regulating HIF-1α activity. Together, lincRNA-p21 and miR-155 coordinate in modulating HIF-1α dynamics, and our work may shed light on the role for ncRNAs in the cellular adaptation to hypoxia.

Bioinspired Hydrophobic Cellulose Nanocrystal Composite Films as Organic-Solvent-Responsive Structural-Color Rewritable Papers.

Lots of beetles, moths, and birds in the natural world present stunning unique structural colors as well as excellent hydrophobic performances. Herein, a novel bioinspired variable structural-color film with organic-solvent responsiveness and surface hydrophobicity was fabricated. Cellulose nanocrystals (CNCs) provided structural color with left-handed helicity. PEG-PPG-PEG triblock copolymers (PPPTCs) were blended with CNCs, giving rise to the organic-solvent-responsive structural color and wider red-shift window of the reflectance peak. The color of the film could be regulated repeatedly under the stimulus of cyclohexanone with an obvious red shift up to 107 nm, corresponding to a macroscopic color change from blue to yellow. Low-surface-energy compound hexadecyltrimethoxysilane (HDTMS) was covalently grafted on the surface in a one-step method to introduce hydrophobicity, successfully preventing the effect of water on the ordered nanostructure. Based on the bionics principle, the as-prepared CNC/PPPTC nanocomposite films with variable structural colors and hydrophobicity are beneficial to their prospective applications in display screens, rewritable hydrophobic structural-color-changing paper, biomimetic sensors, and so forth.

Polysaccharide-based recoverable double-network hydrogel with high strength and self-healing properties.

Polysaccharide-based hydrogels (PSBHs) have received significant attention for numerous bio-applications due to their biocompatibility and non-immunogenic performance. However, the construction of PSBH with superior mechanical properties by a simple method is rarely adequately researched. This study focuses on the construction of a novel PSBH with superior mechanical and recoverable properties by integrating the synergistic and complementary interactions of covalent bond-associated oxidized sodium alginate (SA-CHO) gel and hydrogen bond-associated agarose (Aga) gel. With the synergy and complementarity of the SA-CHO and Aga networks, the hydrogel exhibited 17 and 15 times (20 and 9 times) greater compressive stress and modulus, respectively, compared with the SA-CHO gel (Aga gel). The hydrogel also displayed excellent fatigue resistance, recurrent shapeability, acid resistance and recovery ability, as well as self-healing ability. This study provides a unique perspective for enhancing the mechanical properties of PSBH through the synergy and complementarity of different kinds of polysaccharides without sacrificing the functionality of the PSBH.

Humidity and Heat Dual Response Cellulose Nanocrystals/Poly(N-Isopropylacrylamide) Composite Films with Cyclic Performance.

It has been widely reported that cellulose nanocrystals (CNCs) demonstrate a special structural color, which stems from chiral nematic domains. Herein, the humidity and heat dual response nanocomposite films with multilayered helical structure were prepared by self-assembling of CNCs and hydrazone groups modified poly(N-isopropylacrylamide) (PNIPAM) copolymers. Furthermore, glutaraldehyde was involved to act as a chemical linker to improve cyclic stability by forming acylhydrazone bonds. The structural color of the films could be easily regulated by humidity, heat, or the content of modified PNIPAM copolymers. The absorption of water in higher humidity led to volume expansion of the resin, resulting in a red shift for up to 145 nm. In contrast, the resin shrank under the temperature above the lower critical solution temperature of PNIPAM, leading to a blue shift for up to 87 nm. It was notable that the change of color can be easily captured by the naked eyes. Moreover, the films exhibited excellent stability and cyclicity in response to either vapor or liquid water due to the chemical linking between CNCs and resins. The as-prepared CNCs/PNIPAM nanocomposite films with humidity or heat responsibilities are promising in stimuli-responsive sensors, printing industry, surface decorations, and so forth.

Coordination of miR-192 and miR-22 in p53-Mediated Cell Fate Decision.

p53-targeted microRNAs (miRNAs) markedly affect cellular response to DNA damage. These miRNAs may contribute to either cell cycle arrest or apoptosis induction. However, how these miRNAs coordinate to modulate the decision between cell survival and death remains less understood. Here, we developed an integrated model of p53 signaling network to investigate how p53-targeted miR-192 and miR-22 modulate cellular outcome in response to DNA damage. By numerical simulations, we found that p53 is activated progressively depending on the extent of DNA damage. Upon moderate damage, p53 rises to medium levels and induces miR-192 to promote its own activation, facilitating p21 induction and cell cycle arrest. Upon severe damage, p53 reaches high levels and is fully activated due to phosphatase and tensin homolog (PTEN) induction. As a result, it transactivates miR-22 to repress p21 expression and activate E2F1, resulting in apoptosis. Therefore, miR-192 promotes primary activation of p53, while miR-22 promotes apoptosis by downregulating p21. This work may advance the understanding of the mechanism for cell fate decision between life and death by p53-inducible miRNAs.

Using spatio-temporal lagged association pattern to unravel the acute effect of air pollution on mortality.

BACKGROUND: Acute mortality effects of air pollution have been recognized in plenty of environmental epidemiologic studies. However, existing studies usually assume a universal lag association across sites and seasons. Such a strategy ignores the heterogeneity of lag structures and may lead to bias in the estimation of effects. METHODS: A Bayesian hierarchical model with flexible lag structures was applied to estimate the impact of particulate matter less than 10 µm (PM10) on mortality and determine whether the lag structure varied by season and location. Data from nine US communities, obtained from the National Morbidity, Mortality, and Air Pollution Study (NMMAPS), was used to examine the lagged associations between PM10 and daily mortality. The estimates obtained from the flexible lag approaches were compared with those from the universal lag approach. RESULTS: Of potential varying lag structures, a 10-µg/m3 increase in PM10 was associated with 0.32% (95% credible interval: 0.16, 0.45) and 0.36% (0.18, 0.52) increases in mortality from nonaccidental and cardiovascular-respiratory death. The community-specific estimates of PM10 mortality effects were distinct between the flexible and the universal lag approaches, with relative change of the effects ranged from -7.21% to 9.25% for nonaccidental morality, and from -5.78% to 4.16% for cardiovascular-respiratory morality. Moreover, the lag structure varied by location and season. For instance, the nonaccidental mortality effect of PM10 attributable to the current and previous day was 29.8% in El Paso while 55.0% in Chicago; the overall effect attributable to the previous two to five days were 60.6%, 51.9%, 59.5%, and 59.3% in winter, spring, summer, and fall, respectively. CONCLUSION: The results indicated that a universal lag association across sites and seasons may bias the mortality effect of air pollution. The varying lag structures should be considered in studies of short-term environmental exposures to get a more precise effect estimate.

Fabrication of a Controlled in Situ Forming Polypeptide Hydrogel with a Good Biological Compatibility and Shapeable Property.

A hydrogel is required to have a good biocompatibility, permeability for nutrients, and an easy construction procedure for biomedical applications. In particular, in situ forming hydrogels (ISFHs) have triggered considerable interest in their facile preparation methods. Here, an enzyme-prompted ISF, biodegradable poly(l-lysine)-graft-4-hydroxyphenylacetic acid (PLL-g-HPA) hydrogel in the conditions of horseradish peroxidase (HRP) and hydrogen peroxide (H2O2) and with a good biocompatibility was developed. The gelling time varied from a couple of seconds to several minutes depending on the amounts of catalyst, H2O2, and polymer. Due to the conveniently ISF means, the fabricated hydrogel could be applied in any form according to the need. The hydrogels display a good biological compatibility, as demonstrated in vitro cell culture and attachment experiments. Besides, the remaining NH2 groups in the hydrogel could be further functionalized for various cell research and bioapplications.