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1.
Sensors (Basel) ; 24(12)2024 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-38931635

RESUMO

In this review, recent advances regarding the integration of machine learning into electrochemical analysis are overviewed, focusing on the strategies to increase the analytical context of electrochemical data for enhanced machine learning applications. While information-rich electrochemical data offer great potential for machine learning applications, limitations arise when sensors struggle to identify or quantitatively detect target substances in a complex matrix of non-target substances. Advanced machine learning techniques are crucial, but equally important is the development of methods to ensure that electrochemical systems can generate data with reasonable variations across different targets or the different concentrations of a single target. We discuss five strategies developed for building such electrochemical systems, employed in the steps of preparing sensing electrodes, recording signals, and analyzing data. In addition, we explore approaches for acquiring and augmenting the datasets used to train and validate machine learning models. Through these insights, we aim to inspire researchers to fully leverage the potential of machine learning in electroanalytical science.

2.
Sci Total Environ ; 927: 172099, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38580115

RESUMO

Until now, bacteria able to degrade, 3,3'-iminodipropionitrile (IDPN), a neurotoxin that destroys vestibular hair cells, causing ototoxicity, culminating in irreversible movement disorders, had never been isolated. The aim of this study was to isolate a novel IDPN-biodegrading microorganism and characterize its metabolic pathway. Enrichment was performed by inoculating activated sludge from a wastewater treatment bioreactor that treated IDPN-contaminated wastewater in M9 salt medium, with IDPN as the sole carbon source. A bacterial strain with a spherical morphology that could grow at high concentrations was isolated on a solid medium. Growth of the isolated strain followed the Monod kinetic model. Based on the 16S rRNA gene, the isolate was Paracoccus communis. Whole-genome sequencing revealed that the isolated P. communis possessed the expected full metabolic pathway for IDPN biodegradation. Transcriptome analyses confirmed the overexpression of the gene encoding hydantoinase/oxoprolinase during the exponential growth phase under IDPN-fed conditions, suggesting that the enzyme involved in cleaving the imine bond of IDPN may promote IDPN biodegradation. Additionally, the newly discovered P. communis isolate seems to metabolize IDPN through cleavage of the imine bond in IDPN via nitrilase, nitrile hydratase, and amidase reactions. Overall, this study lays the foundation for the application of IDPN-metabolizing bacteria in the remediation of IDPN-contaminated environments.


Assuntos
Biodegradação Ambiental , Reatores Biológicos , Nitrilas , Paracoccus , Eliminação de Resíduos Líquidos , Águas Residuárias , Nitrilas/metabolismo , Paracoccus/metabolismo , Paracoccus/genética , Eliminação de Resíduos Líquidos/métodos , Poluentes Químicos da Água/metabolismo , RNA Ribossômico 16S
3.
Can J Hosp Pharm ; 77(1): e3459, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38204500

RESUMO

Background: In February 2020, the Fraser Health Authority in British Columbia introduced an automatic therapeutic interchange policy, whereby orders for any strength of topical diclofenac would be automatically interchanged to the commercially available diclofenac 2.32% gel for twice-daily administration. The new policy was intended mainly as a cost-saving measure but had the potential for clinical impacts that needed to be considered. Objectives: To evaluate the financial and clinical impact of the automatic therapeutic interchange policy for topical diclofenac. Methods: A financial evaluation and a clinical evaluation were conducted. Expenditures for topical diclofenac before and after implementation of the automatic therapeutic interchange policy were compared. To obtain information about the clinical impact of the interchange, a retrospective chart review was conducted at long-term care sites. The primary outcome was a composite of 7 components that could indicate worsening of pain in 3 prespecified scenarios. Results: The financial evaluation showed that the interchange could potentially save the health authority more than $200 000 over 12 months. The clinical evaluation showed that 25%-48% of patients met the primary outcome of worsening pain (analyzed according to 3 different scenarios) after the switch to lower-strength diclofenac, with increases in use of as-needed topical diclofenac and other analgesics being the main indicators of worsening pain. Conclusions: An automatic therapeutic interchange policy that switched orders for higher strengths of diclofenac to the 2.32% concentration resulted in large financial savings and, in most cases (52%-75% of patients), did not appear to affect pain control. Prospective studies comparing the clinical impact of higher- and lower-strength topical diclofenac products are warranted.


Contexte: En février 2020, la Fraser Health Authority en Colombie-Britannique a introduit une politique d'échange thérapeutique automatique, selon laquelle les commandes de diclofénac topique (n'importe quelle concentration) seraient automatiquement échangées contre du diclofénac à 2,32 % (formule en gel) disponible dans le commerce pour une administration deux fois par jour. La nouvelle politique visait principalement à réduire les coûts, mais pouvait avoir une incidence clinique, qui devait être prise en compte. Objectifs: Évaluer l'impact financier et clinique de la politique d'échange thérapeutique automatique pour le diclofénac topique. Méthodes: Une évaluation financière et une évaluation clinique ont été réalisées. Les dépenses liées au diclofénac topique avant et après la mise en œuvre de la politique d'échange thérapeutique automatique ont été comparées. Pour obtenir des informations sur l'incidence clinique de l'échange, un examen rétrospectif des dossiers a été réalisé dans les sites de soins de longue durée. Le résultat principal était un composite de 7 éléments pouvant indiquer une aggravation de la douleur dans 3 scénarios prédéfinis. Résultats: L'évaluation financière a montré que l'échange pourrait potentiellement permettre à l'autorité sanitaire d'économiser plus de 200 000 $ sur 12 mois. L'évaluation clinique a quant à elle démontré que 25 à 48 % des patients ont atteint le principal résultat d'aggravation de la douleur (analysé selon 3 scénarios différents) après le passage au diclofénac à plus faible concentration. L'augmentation de l'utilisation au besoin de diclofénac topique et d'autres analgésiques constituait le principal indicateur d'aggravation de la douleur. Conclusions: Une politique d'échange thérapeutique automatique qui remplaçait les ordonnances de concentrations plus élevées de diclofénac par une concentration de 2,32 % a permis de réaliser d'importantes économies financières et, dans la plupart des cas (52 à 75 % des patients), cet échange ne semble pas avoir eu d'effet sur le contrôle de la douleur. Des études prospectives comparant l'incidence clinique des produits topiques à base de diclofénac à concentration plus élevée et plus faible sont justifiées.

4.
ACS Appl Mater Interfaces ; 16(5): 6274-6283, 2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38282293

RESUMO

A novel approach to producing high-color-purity blue-light-emitting diodes based on single-crystalline Ruddlesden-Popper perovskites (RPPs) is reported. The utilization of a pure bromide composition eliminates any possibility of halide segregation, which can otherwise lead to undesired shifts in the emission wavelength or irreversible degradation of the spectral line width. Phase-pure PEA2MAPb2Br7 single crystals with a lateral size exceeding 1 cm2 can be synthesized using the inverse temperature crystallization method. To prepare RPP layers with a thickness of less than 50 nm, we employ a thinning process of the initially thick bulk crystals, followed by a dry-transfer process to place them onto a hole transport layer and an indium-tin-oxide-coated glass substrate. By utilizing polydimethylsiloxane as a handling layer, deformations of the bulk RPP crystal and exfoliated RPP layer, as well as the formation of defects such as pinholes, can be effectively suppressed. Subsequent depositions of an electron transport layer and a metal contact complete the fabrication of electroluminescence (EL) devices. The EL devices utilizing the single-crystalline RPP demonstrate excellent spectral stability across a broad range of the applied bias voltage spanning from 4.5 to 10 V, exhibiting a significantly narrow line width of 14 nm at an emission wavelength of 440 nm that can potentially cover 99.3% of the Rec. 2020 color gamut. The sharp EL emission spectrum can be effectively preserved, avoiding any broadening of the line width, by suppressing Joule heating throughout the device operation, in addition to the intrinsic stability of single-crystalline RPPs.

5.
Cell Metab ; 35(2): 345-360.e7, 2023 02 07.
Artigo em Inglês | MEDLINE | ID: mdl-36754021

RESUMO

Mitochondrial components have been abundantly detected in bone matrix, implying that they are somehow transported extracellularly to regulate osteogenesis. Here, we demonstrate that mitochondria and mitochondrial-derived vesicles (MDVs) are secreted from mature osteoblasts to promote differentiation of osteoprogenitors. We show that osteogenic induction stimulates mitochondrial fragmentation, donut formation, and secretion of mitochondria through CD38/cADPR signaling. Enhancing mitochondrial fission and donut formation through Opa1 knockdown or Fis1 overexpression increases mitochondrial secretion and accelerates osteogenesis. We also show that mitochondrial fusion promoter M1, which induces Opa1 expression, impedes osteogenesis, whereas osteoblast-specific Opa1 deletion increases bone mass. We further demonstrate that secreted mitochondria and MDVs enhance bone regeneration in vivo. Our findings suggest that mitochondrial morphology in mature osteoblasts is adapted for extracellular secretion, and secreted mitochondria and MDVs are critical promoters of osteogenesis.


Assuntos
Mitocôndrias , Osteogênese , Osteogênese/fisiologia , Mitocôndrias/metabolismo , Osteoblastos/metabolismo , Dinâmica Mitocondrial , Diferenciação Celular
6.
Water Res ; 231: 119654, 2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-36702020

RESUMO

In a hydrogen-based membrane biofilm reactor (H2-MBfR), the biofilm thickness is considered to be one of the most important factors for denitrification. Thick biofilms in MBfRs are known for low removal fluxes owing to their resistance to substrate transport. In this study, the H2-MBfR was operated under various loading rates of oxyanions, such as NO3-N, SO4-S, and ClO4- at an H2 flux of 1.06 e- eq/m2-d. The experiment was initiated with NO3-N, SO4-S, and ClO4- loadings of 0.464, 0.026, and 0.211 e- eq/m2-d, respectively, at 20 °C. Under the most stressful conditions, the loading rates increased simultaneously to 1.911, 0.869, and 0.108 e- eq/m2-d, respectively, at 10 °C. We observed improved performance in significantly thicker biofilms (approximately 2.7 cm) compared to previous studies using a denitrifying H2-MBfR for 120 days. Shock oxyanion loadings led to a decrease in total nitrogen (TN) removal by 20 to 30%, but TN removal returned to 100% within a few days. Similarly, complete denitrification was observed, even at 10 °C. The protective function and microbial diversity of the thick biofilm may allow stable denitrification despite stress-imposing conditions. In the microbial community analysis, heterotrophs were dominant and acetogens accounted for 11% of the biofilm. Metagenomic results showed a high abundance of functional genes involved in organic carbon metabolism and homoacetogenesis. Owing to the presence of organic compounds produced by acetogens and autotrophs, heterotrophic denitrification may occur simultaneously with autotrophic denitrification. As a result, the total removal flux of oxyanions (1.84 e- eq/m2-d) far exceeded the H2 flux (1.06 e- eq/m2-d). Thus, the large accumulation of biofilms could contribute to good resilience and enhanced removal fluxes.


Assuntos
Desnitrificação , Hidrogênio , Reatores Biológicos , Nitratos/metabolismo , Biofilmes , Nitrogênio
7.
Bioresour Technol ; 364: 128115, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36252764

RESUMO

Direct interspecies electron transfer (DIET) is a syntrophic mechanism for electron transfer between exo- and endoelectrogens. Previous studies have demonstrated that methanogenesis performance was significantly improved via the DIET mechanism through conductive materials (CMs) under batch conditions with a single substrate, while that under continuous condition is still under investigation. To investigate how the DIET via CM on methanogenesis performance was changed in response to the different substrates (acetate versus glucose)-fed in continuous anaerobic bioreactors, continuous bioreactors were operated by cross-feeding with acetate and glucose. Acetate-fed conditions showed 0.40 day shorten lagtime, 1.88- and 1.22-folds higher methane production rate, and ultimate methane production than glucose-fed conditions, respectively. Burkholderiaceae- and Anaerolineaceae-related exo-electrogenic populations were enriched with low abundance of Geobacter species in batch reactors. Furthermore, influent substrates affected the distribution of the enriched populations. Taken together, the results suggested that different syntrophic associations contributed methane production by DIET in continuous bioreactors.

8.
Bioresour Technol ; 363: 127931, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36100185

RESUMO

The production of polyethylene terephthalate (PET) has drastically increased in the past half-century, reaching 30 million tons every year. The accumulation of this recalcitrant waste now threatens diverse ecosystems. Despite efforts to recycle PET wastes, its rate of recycling remains limited, as the current PET downcycling is mostly unremunerative. To address this problem, PET bio-upcycling, which integrates microbial depolymerization of PET followed by repolymerization of PET-derived monomers into value-added products, has been suggested. This article critically reviews current understanding of microbial PET hydrolysis, the metabolic mechanisms involved in PET degradation, PET hydrolases, and their genetic improvement. Furthermore, this review includes the use of meta-omics approaches to search PET-degrading microbiomes, microbes, and putative hydrolases. The current development of biosynthetic technologies to convert PET-derived materials into value-added products is also comprehensively discussed. The integration of various depolymerization and repolymerization biotechnologies enhances the prospects of a circular economy using waste PET.


Assuntos
Microbiota , Polietilenotereftalatos , Biotecnologia , Hidrolases/metabolismo , Polietilenotereftalatos/metabolismo , Reciclagem
9.
Bioresour Technol ; 352: 127079, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35367324

RESUMO

To apply the anammox processes into the mainstream of domestic wastewater treatment plants, two laboratory-scale sequence batch reactors have been developed and used with two different activated sludges seeded in each sequence batch reactors with gradually increases influent total nitrogen concentrations under low nitrogen loading rates. During 320 days of operation, both sequence batch reactors showed high specific anammox activity (0.68 - 0.75 kgN kg-1VSS d-1) and a nitrogen removal efficiency of 97.50%. To monitor changes in microbial community dynamics during enrichment, high-throughput sequencing analysis was performed. Members taxonomically affiliated with Candidatus Jettenia were markedly enriched and predominant in both sequence batch reactors in response to the increasing influent total nitrogen concentrations. These results suggest that Candidatus Jettenia might be a prominent anammox genus under low nitrogen loading rate with high total nitrogen concentration conditions and could be suitably applied to the mainstream process of domestic wastewater treatment systems.


Assuntos
Reatores Biológicos , Nitrogênio , Anaerobiose , Nitrogênio/análise , Oxirredução , Esgotos , Águas Residuárias/análise
10.
Lab Anim Res ; 38(1): 1, 2022 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-34996527

RESUMO

BACKGROUND: The convertase subtilisin/kexin family 1 gene (PCSK1) has been associated in various human genetics studies with a wide spectrum of metabolic phenotypes, including early-onset obesity, hyperphagia, diabetes insipidus, and others. Despite the evident influence of PCSK1 on obesity and the known functions of other PCSKs in lipid metabolism, the role of PCSK1 specifically in lipid and cholesterol metabolism remains unclear. This study evaluated the effect of loss of PCSK1 function on high-density lipoprotein (HDL) metabolism in mice. RESULTS: HDL cholesterol, apolipoprotein A1 (APOA1) levels in serum and liver, and the activities of two enzymes (lecithin-cholesterol acyltransferase, LCAT and phospholipid transfer protein, PLTP) were evaluated in 8-week-old mice with a non-synonymous single nucleotide mutation leading to an amino acid substitution in PCSK1, which results in a loss of protein's function. Mutant mice had similar serum HDL cholesterol concentration but increased levels of serum total and mature APOA1, and LCAT activity in comparison to controls. CONCLUSIONS: This study presents the first evaluation of the role of PCSK1 in HDL metabolism using a loss-of-function mutant mouse model. Further investigations will be needed to determine the underlying molecular mechanism.

11.
Bioresour Technol ; 344(Pt B): 126350, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34813924

RESUMO

Anaerobic digestion (AD) is a technique that can be used to treat high concentrations of various organic wastes using a consortium of functionally diverse microorganisms under anaerobic conditions. Methane gas, a beneficial by-product of the AD process, is a renewable energy source that can replace fossil fuels following purification. However, detailed functional roles and metabolic interactions between microbial populations involved in organic waste removal and methanogenesis are yet to be known. Recent metagenomic approaches based on advanced high-throughput sequencing techniques have enabled the exploration of holistic microbial taxonomy and functionality of complex microbial populations involved in the AD process. Gene-centric and genome-centric analyses based on metagenome-assembled genomes are a platform that can be used to study the composition of microbial communities and their roles during AD. This review looks at how these up-to-date metagenomic analyses can be applied to promote our understanding and improved the development of the AD process.


Assuntos
Reatores Biológicos , Metagenoma , Anaerobiose , Metagenômica , Metano
12.
Psychoneuroendocrinology ; 134: 105448, 2021 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-34687965

RESUMO

The prevalence of depression is higher among people with type 2 diabetes (T2DM). Individually, both conditions are associated with systemic inflammation. This study aimed to summarize the clinical data comparing peripheral inflammatory markers in blood between people with T2DM, with and without comorbid depression. From 2187 records, we identified 20 original peer-reviewed articles from which blood inflammatory marker concentrations could be combined and compared between people with T2DM and comorbid depression (D) vs. no depression (ND) as standardized mean differences (SMD) in random effects meta-analysis. Concentrations of C-reactive protein (CRP; ND/NND = 1742/15244, SMD = 0.31 95% confidence interval [0.16, 0.45], Z16 = 4.03, p < 0.01; I2 = 84.0%) and interleukin-6 (IL-6; ND/NND = 677/4349, SMD = 0.17 [0.04, 0.30], Z4 = 2.58, p = 0.01; I2 = 48.1%), were higher, and concentrations of brain derived neurotrophic factor (BDNF; ND/NND = 358/1512, SMD = -0.37 95% confidence interval [-0.64,-0.10], Z2 = -2.68, p = 0.01; I2 = 61.2%) were lower, among those with depression. Depression in T2DM was associated with systemic inflammation and lower peripheral blood BDNF concentrations. Inconsistency between studies suggests the need to explore further population heterogeneity and pathophysiological elements. PROSPERO (CRD42020188509).

13.
ACS Appl Mater Interfaces ; 13(31): 37323-37330, 2021 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-34337932

RESUMO

Highly efficient vacuum-deposited CsPbBr3 perovskite light-emitting diodes (PeLEDs) are demonstrated by introducing a separate polyethylene oxide (PEO) passivation layer. A CsPbBr3 film deposited on the PEO layer via thermal co-evaporation of CsBr and PbBr2 exhibits an almost 50-fold increase in photoluminescence quantum yield intensity compared to a reference sample without PEO. This enhancement is attributed to the passivation of interfacial defects of the perovskite, as evidenced by temperature-dependent photoluminescence measurements. However, direct application of PEO to an LED device is challenging because of the electrically insulating nature of PEO. This issue is solved by doping PEO layers with MgCl2. This strategy results in an enhanced luminance and external quantum efficiency (EQE) of up to 6887 cd m-2 and 7.6%, respectively. To the best of our knowledge, this is the highest EQE reported to date among vacuum-deposited PeLEDs.

14.
J Hazard Mater ; 418: 126365, 2021 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-34329019

RESUMO

As the most widely used anionic surfactant, linear alkylbenzene sulfonate (LAS) requires biological alkane degradation when it is treated using an activated sludge (AS) process in a wastewater treatment plant because of its structural carboxylic unavailability. As consumption of LAS is gradually increasing, LAS loading into the WWTP is accordingly increasing. However, fewer studies have examined the involvement of the AS microbial community in the LAS degradation. In this study, metagenomic approaches were used to define microbiomes involved in LAS degradation in AS, with a particular focus on ω-hydroxylation. The abundance and diversity of alkane-degrading genes were investigated, and these genes were integrated with reconstructed metagenome-assembled genomes (MAGs). Additionally, the association of functional genes and MAGs with respect to LAS degradation was investigated. The results showed that alkB and cytochrome P450 genes were only shared within specific MAGs. Unique sets of genes with diverse abundances were detected in each sample. The MAGs with the alkB and cytochrome P450 genes were strongly associated with the other MAGs and involved in positive commensal interactions. The findings provided significant insights into how the AS microbiomes, which have continuously treated anionic surfactants for decades, potentially metabolize LAS and interact with commensal bacteria.


Assuntos
Ácidos Alcanossulfônicos , Microbiota , Metagenoma , Microbiota/genética , Esgotos , Tensoativos
15.
Proc Natl Acad Sci U S A ; 117(9): 4910-4920, 2020 03 03.
Artigo em Inglês | MEDLINE | ID: mdl-32071240

RESUMO

Growth and differentiation factor 11 (GDF11) and myostatin (MSTN) are closely related transforming growth factor ß (TGF-ß) family members, but their biological functions are quite distinct. While MSTN has been widely shown to inhibit muscle growth, GDF11 regulates skeletal patterning and organ development during embryogenesis. Postnatal functions of GDF11, however, remain less clear and controversial. Due to the perinatal lethality of Gdf11 null mice, previous studies used recombinant GDF11 protein to prove its postnatal function. However, recombinant GDF11 and MSTN proteins share nearly identical biochemical properties, and most GDF11-binding molecules have also been shown to bind MSTN, generating the possibility that the effects mediated by recombinant GDF11 protein actually reproduce the endogenous functions of MSTN. To clarify the endogenous functions of GDF11, here, we focus on genetic studies and show that Gdf11 null mice, despite significantly down-regulating Mstn expression, exhibit reduced bone mass through impaired osteoblast (OB) and chondrocyte (CH) maturations and increased osteoclastogenesis, while the opposite is observed in Mstn null mice that display enhanced bone mass. Mechanistically, Mstn deletion up-regulates Gdf11 expression, which activates bone morphogenetic protein (BMP) signaling pathway to enhance osteogenesis. Also, mice overexpressing follistatin (FST), a MSTN/GDF11 inhibitor, exhibit increased muscle mass accompanied by bone fractures, unlike Mstn null mice that display increased muscle mass without fractures, indicating that inhibition of GDF11 impairs bone strength. Together, our findings suggest that GDF11 promotes osteogenesis in contrast to MSTN, and these opposing roles of GDF11 and MSTN must be considered to avoid the detrimental effect of GDF11 inhibition when developing MSTN/GDF11 inhibitors for therapeutic purposes.


Assuntos
Proteínas Morfogenéticas Ósseas/metabolismo , Osso e Ossos/metabolismo , Fatores de Diferenciação de Crescimento/metabolismo , Desenvolvimento Muscular/fisiologia , Miostatina/metabolismo , Osteogênese/fisiologia , Animais , Proteínas Morfogenéticas Ósseas/genética , Osso e Ossos/patologia , Condrócitos/metabolismo , Regulação para Baixo , Folistatina , Regulação da Expressão Gênica no Desenvolvimento , Fatores de Diferenciação de Crescimento/genética , Camundongos , Camundongos Knockout , Músculos/patologia , Osteoblastos/metabolismo , Transdução de Sinais , Fator de Crescimento Transformador beta/metabolismo
16.
PLoS One ; 15(2): e0228418, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32012189

RESUMO

As eBook readers have expanded on the market, various online eBook markets have arisen as well. Currently, the online eBook market consists of at least publishers and online platform providers and authors, and these actors inevitably incur intermediate costs between them. In this paper, we introduce a blockchain-based eBook market system that enables self-published eBook trading and direct payments from readers to authors without any trusted party; because authors publish themselves and readers purchase directly from authors, neither actor incurs any intermediate costs. However, because of this trustless environment, the validity, ownership and intellectual property of digital contents cannot be verified and protected, and the safety of purchase transactions cannot be ensured. To address these shortcomings, we propose a secure and reliable eBook transaction system that satisfies the following security requirements: (1) verification of the ownership of each eBook, (2) confidentiality of eBook contents, (3) authorization of a right to read a book, (4) authentication of a legitimate purchaser, (5) verification of the validity and integrity of eBook contents, (6) safety of direct purchase transactions, and (7) preventing eBook piracy and illegal distribution. We provide practical cryptographic protocols for the proposed system and analyze the security and simulated performance of the proposed schemes.


Assuntos
Blockchain/estatística & dados numéricos , Livros , Segurança Computacional , Confidencialidade/normas , Internet/normas , Editoração/economia , Editoração/normas , Algoritmos , Humanos
17.
J Cell Physiol ; 234(12): 23360-23368, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31183862

RESUMO

Growth and differentiation factor 11 (GDF11) is a transforming growth factor ß family member that has been identified as the central player of anterior-posterior (A-P) axial skeletal patterning. Mice homozygous for Gdf11 deletion exhibit severe anterior homeotic transformations of the vertebrae and craniofacial defects. During early embryogenesis, Gdf11 is expressed predominantly in the primitive streak and tail bud regions, where new mesodermal cells arise. On the basis of this expression pattern of Gdf11 and the phenotype of Gdf11 mutant mice, it has been suggested that GDF11 acts to specify positional identity along the A-P axis either by local changes in levels of signaling as development proceeds or by acting as a morphogen. To further investigate the mechanism of action of GDF11 in the vertebral specification, we used a Cdx2-Cre transgene to generate mosaic mice in which Gdf11 expression is removed in posterior regions including the tail bud, but not in anterior regions. The skeletal analysis revealed that these mosaic mice display patterning defects limited to posterior regions where Gdf11 expression is deficient, whereas displaying normal skeletal phenotype in anterior regions where Gdf11 is normally expressed. Specifically, the mosaic mice exhibited seven true ribs, a pattern observed in wild-type (wt) mice (vs. 10 true ribs in Gdf11-/- mice), in the anterior axis and nine lumbar vertebrae, a pattern observed in Gdf11 null mice (vs. six lumbar vertebrae in wt mice), in the posterior axis. Our findings suggest that GDF11, rather than globally acting as a morphogen secreted from the tail bud, locally regulates axial vertebral patterning.


Assuntos
Padronização Corporal , Proteínas Morfogenéticas Ósseas/metabolismo , Fatores de Diferenciação de Crescimento/metabolismo , Osteogênese , Coluna Vertebral/metabolismo , Animais , Padronização Corporal/genética , Proteínas Morfogenéticas Ósseas/deficiência , Proteínas Morfogenéticas Ósseas/genética , Regulação da Expressão Gênica no Desenvolvimento , Fatores de Diferenciação de Crescimento/deficiência , Fatores de Diferenciação de Crescimento/genética , Camundongos Endogâmicos C57BL , Camundongos Knockout , Mosaicismo , Osteogênese/genética , Transdução de Sinais , Coluna Vertebral/embriologia
19.
Water Res ; 90: 395-404, 2016 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-26771162

RESUMO

Soluble microbial products (SMP) produced in bioprocesses have been known as a main cause to decrease treatment efficiency, lower effluent quality, and promote membrane fouling in water reclamation plants. In this study, biological degradation of SMP using selectively enriched microbial consortia in a down-flow hanging sponge (DHS) reactor was introduced to remove SMP discharged from anaerobic methanogenic reactors. On average, 68.9-87.5% SMP removal was achieved by the enriched microbial consortia in the DHS reactor for >800 days. The influent SMP fed to the DHS reactor exhibited a bimodal molecular weight (MW) distribution with 14-20 kDa and <4 kDa. Between these two types of SMP, the small MW SMP were biodegraded in the upper part of the reactor, together with most of the large MW SMP. Using 16S rRNA gene pyrosequencing technology, the microbial community composition and structure were characterized and correlated with operational factors, such as hydraulic retention time, organic loading rate, and removal of soluble chemical oxygen demand at different depths of the reactor, by performing network and redundancy analyses. The results revealed that Saprospiraceae was strongly correlated to the increasing SMP loading condition, indicating positive co-occurrences with neighboring bacterial populations. Different microbial diversity along with the depth of the reactor implies that stratified microbial communities could participate in the process of SMP degradation. Taken together, these observations indicate that the spatial and temporal variability of the enriched microbial community in the DHS reactor could effectively treat SMP with respect to changes in the operational factors.


Assuntos
Reatores Biológicos/microbiologia , Metano/química , Consórcios Microbianos , Microbiologia da Água , Anaerobiose , Biodegradação Ambiental , Análise da Demanda Biológica de Oxigênio , Membranas Artificiais , Peso Molecular , Análise de Componente Principal , RNA Ribossômico 16S/análise , Análise de Sequência de DNA , Esgotos/química , Eliminação de Resíduos Líquidos/métodos , Água
20.
Res Social Adm Pharm ; 12(3): 428-37, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26361821

RESUMO

BACKGROUND: A significant financial burden arises from medication errors that cause direct injury and those without patient harm that represent waste and inefficiency. OBJECTIVE: To estimate the incidence, types, and causes of medication errors as well as their attributable costs in a hospital setting. METHODS: For a retrospective case-control study, data were collected for 57,554 patients admitted to two New Jersey (U.S. State) hospitals during 2005-2006 as well as hospital-specific voluntary error reports from these two hospitals for the same period. Medication errors were classified into categories of stage, error type, and proximal cause, and the incidence was estimated. The costs attributable to medication errors were calculated using both the recycled prediction method, and the Blinder-Oaxaca decomposition method after propensity score matching. RESULTS: Medication errors occurred at a rate of 0.8 per 100 admissions, or 1.6 per 1000 patient days. Most errors occurred at the administration stage of the medication use process. The most frequent types of errors were wrong time, wrong medication, wrong dose, and omission errors. Treatment costs attributable to medication errors were in the range of $8,439 using the Blinder-Oaxaca decomposition method and $8,898 using the recycled prediction method. CONCLUSIONS: Medication errors are associated with significant additional costs, even without patient harm. Considering the substantial costs associated with adverse drug events, the elimination of medication errors should be further emphasized and promoted, and guidelines should be developed to facilitate this goal.


Assuntos
Custos de Cuidados de Saúde , Hospitalização/estatística & dados numéricos , Erros de Medicação/estatística & dados numéricos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Hospitalização/economia , Hospitais/estatística & dados numéricos , Humanos , Masculino , Erros de Medicação/economia , Pessoa de Meia-Idade , New Jersey , Adulto Jovem
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