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1.
Waste Manag ; 109: 10-18, 2020 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-32375080

RESUMEN

Critical materials (CMs) are vital to modern technology. Components of modern vehicles can be recycled to recover and reuse the CMs to help ensure a supply of these materials. Electronic components from a 2015 GMC Sierra truck (21 components) and 2016 Toyota Camry sedan (10 components) were analyzed for CMs. The components were processed via size reduction, aqua regia leaching and dissolution, and final solutions were analyzed for metal content. It was found that most electronic components of both vehicles contain CMs. The most concentrated CMs in the components were Sn, Nb, and Tb. Nd and Co were found in several of the magnetic components. CM economic value was found to be low compared to the overall value of the components, and the CM content would not allow for a viable pathway for recycling. Remanufacturing of components may be a more economic option of reuse in the future.


Asunto(s)
Electrónica , Reciclaje , Metales , Vehículos a Motor , Tecnología
2.
Ecol Evol ; 6(23): 8341-8351, 2016 12.
Artículo en Inglés | MEDLINE | ID: mdl-28031787

RESUMEN

Using an automated cell counting technique developed previously (Case et al., Ecology and Evolution 2014; 4: 3494), we explore the lifespan effects of lac-1, a ceramide synthase gene paralogous to lag-1 in Neurospora crassa in conjunction with the band bd (ras-1) gene. We find that the replicative lifespan of a lac-1KObd double mutants is short, about one race tube cycle, and this double mutant lacks a strong ~21-hr clock cycle as shown by race tube and fluorometer analysis of fluorescent strains including lac-1KO . This short replicative lifespan phenotype is contrasted with a very long estimated chronological lifespan for lac-1KObd double mutants from 247 to 462 days based on our regression analyses on log viability, and for the single mutant lac-1KO, 161 days. Both of these estimated lifespans are much higher than that of previously studied WT and bd single mutant strains. In a lac-1 rescue and induction experiment, the expression of lac-1+ as driven by a quinic acid-dependent promoter actually decreases the median chronological lifespan of cells down to only 7 days, much lower than the 34-day median lifespan found in control bd conidia also grown on quinic acid media, which we interpret as an effect of balancing selection acting on ceramide levels based on previous findings from the literature. Prior work has shown phytoceramides can act as a signal for apoptosis in stressed N. crassa cells. To test this hypothesis of balancing selection on phytoceramide levels, we examine the viability of WT, lag-1KObd, and lac-1KObd strains following the dual stresses of heat and glycolysis inhibition, along with phytoceramide treatments of different dosages. We find that the phytoceramide dosage-response curve is altered in the lag-1KObd mutant, but not in the lac-1KObd mutant. We conclude that phytoceramide production is responsible for the previously reported longevity effects in the lag-1KObd mutant, but a different ceramide may be responsible for the longevity effect observed in the lac-1KObd mutant.

3.
Ecol Evol ; 4(17): 3494-507, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-25535564

RESUMEN

The biological clock affects aging through ras-1 (bd) and lag-1, and these two longevity genes together affect a clock phenotype and the clock oscillator in Neurospora crassa. Using an automated cell-counting technique for measuring conidial longevity, we show that the clock-associated genes lag-1 and ras-1 (bd) are true chronological longevity genes. For example, wild type (WT) has an estimated median life span of 24 days, while the double mutant lag-1, ras-1 (bd) has an estimated median life span of 120 days for macroconidia. We establish the biochemical function of lag-1 by complementing LAG1 and LAC1 in Saccharomyces cerevisiae with lag-1 in N. crassa. Longevity genes can affect the clock as well in that, the double mutant lag-1, ras-1 (bd) can stop the circadian rhythm in asexual reproduction (i.e., banding in race tubes) and lengthen the period of the frequency oscillator to 41 h. In contrast to the ras-1 (bd), lag-1 effects on chronological longevity, we find that this double mutant undergoes replicative senescence (i.e., the loss of replication function with time), unlike WT or the single mutants, lag-1 and ras-1 (bd). These results support the hypothesis that sphingolipid metabolism links aging and the biological clock through a common stress response.

4.
Pediatr Radiol ; 44 Suppl 4: S632-40, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25501735

RESUMEN

This article will discuss accidental and inflicted head injuries in infants and young children and how forensic pathologists distinguish between these types of injuries. The article begins with a consideration of the special and unique features of the anatomy and development of the child's head and neck and then relates these features to the mechanisms of traumatic brain injury and how these unique features influence the mechanisms of injury. The article very specifically notes that accidental head injuries in young children that occur in and around the home are focal head injuries in distinction to inflicted head injuries, which are diffuse brain injuries. The article discusses the mechanisms by which traumatic brain injury causes loss of consciousness and relates those mechanisms to the differences in the clinical features that occur in both accidental and inflicted head injury. The article discusses and illustrates the pathological findings in accidental head injuries consisting of the crushing head injuries and the head injuries sustained in short falls including epidural hemorrhage and focal subdural hemorrhage. The article discusses and illustrates the pathological findings that occur in inflicted head trauma, including subdural and subarachnoid hemorrhages and retinal and optic nerve sheath hemorrhages.


Asunto(s)
Accidentes , Autopsia/métodos , Maltrato a los Niños/diagnóstico , Traumatismos Craneocerebrales/patología , Medicina Legal/métodos , Niño , Preescolar , Diagnóstico Diferencial , Femenino , Humanos , Recién Nacido , Imagen por Resonancia Magnética/métodos , Masculino , Tomografía Computarizada por Rayos X/métodos
5.
PLoS One ; 6(6): e20671, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21695121

RESUMEN

An ensemble of genetic networks that describe how the model fungal system, Neurospora crassa, utilizes quinic acid (QA) as a sole carbon source has been identified previously. A genetic network for QA metabolism involves the genes, qa-1F and qa-1S, that encode a transcriptional activator and repressor, respectively and structural genes, qa-2, qa-3, qa-4, qa-x, and qa-y. By a series of 4 separate and independent, model-guided, microarray experiments a total of 50 genes are identified as QA-responsive and hypothesized to be under QA-1F control and/or the control of a second QA-responsive transcription factor (NCU03643) both in the fungal binuclear Zn(II)2Cys6 cluster family. QA-1F regulation is not sufficient to explain the quantitative variation in expression profiles of the 50 QA-responsive genes. QA-responsive genes include genes with products in 8 mutually connected metabolic pathways with 7 of them one step removed from the tricarboxylic (TCA) Cycle and with 7 of them one step removed from glycolysis: (1) starch and sucrose metabolism; (2) glycolysis/glucanogenesis; (3) TCA Cycle; (4) butanoate metabolism; (5) pyruvate metabolism; (6) aromatic amino acid and QA metabolism; (7) valine, leucine, and isoleucine degradation; and (8) transport of sugars and amino acids. Gene products both in aromatic amino acid and QA metabolism and transport show an immediate response to shift to QA, while genes with products in the remaining 7 metabolic modules generally show a delayed response to shift to QA. The additional QA-responsive cutinase transcription factor-1ß (NCU03643) is found to have a delayed response to shift to QA. The series of microarray experiments are used to expand the previously identified genetic network describing the qa gene cluster to include all 50 QA-responsive genes including the second transcription factor (NCU03643). These studies illustrate new methodologies from systems biology to guide model-driven discoveries about a core metabolic network involving carbon and amino acid metabolism in N. crassa.


Asunto(s)
Genes Fúngicos/genética , Familia de Multigenes/genética , Neurospora crassa/genética , Ácido Quínico/metabolismo , Biología de Sistemas , Sitios de Unión , Biología Computacional , Perfilación de la Expresión Génica , Regulación Fúngica de la Expresión Génica/efectos de los fármacos , Redes Reguladoras de Genes/genética , Cinética , Análisis de los Mínimos Cuadrados , Modelos Genéticos , Neurospora crassa/efectos de los fármacos , Análisis de Secuencia por Matrices de Oligonucleótidos , Ácido Quínico/farmacología , ARN Mensajero/genética , ARN Mensajero/metabolismo
7.
Brain Pathol ; 18(4): 571-82, 2008 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-18782169

RESUMEN

This article will discuss the subject of inflicted or abusive head injury in infants and young children. Inflicted neurotrauma is a very common injury and a frequent problem in attempting to distinguish between inflicted and accidental injury. Inflicted head injury occurs usually in the home in the presence of the individual who has inflicted the injury outside the view of unbiased witnesses. Distinguishing between inflicted and accidental injury may be dependent upon the pathological findings and consideration of the circumstances surrounding the injury. The most common finding in an inflicted head injury is the presence of subdural hemorrhage. Subdural hemorrhage may occur in a variety of distributions and appearances. The natural history of subdural bleeding and the anatomy of the "subdural" will be considered. The anatomy of the dura and its attachment to the skull and to the arachnoid determines how subdural bleeding evolves into the cleaved dural border cell layer and as well as how bridging veins are torn and anatomically where bleeding will occur. Different biomechanical mechanisms result in different distributions of subdural blood and these differences will be discussed.


Asunto(s)
Lesiones Encefálicas/patología , Violencia Doméstica , Traumatismos Cerrados de la Cabeza/patología , Hematoma Subdural/patología , Encéfalo/irrigación sanguínea , Encéfalo/patología , Encéfalo/fisiopatología , Lesiones Encefálicas/etiología , Lesiones Encefálicas/fisiopatología , Venas Cerebrales/lesiones , Venas Cerebrales/patología , Venas Cerebrales/fisiopatología , Diagnóstico Diferencial , Lesión Axonal Difusa/etiología , Lesión Axonal Difusa/patología , Lesión Axonal Difusa/fisiopatología , Duramadre/irrigación sanguínea , Duramadre/lesiones , Duramadre/patología , Femenino , Traumatismos Cerrados de la Cabeza/etiología , Traumatismos Cerrados de la Cabeza/fisiopatología , Hematoma Subdural/etiología , Hematoma Subdural/fisiopatología , Humanos , Lactante , Masculino
8.
Brain Pathol ; 18(4): 583-9, 2008 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-18782170

RESUMEN

This article will discuss accidental head injuries in infants and young children. The first category of injury is the crushing head injury. Static forces applied slowly to the head result in multiple fractures of the skull and contusions and lacerations of the brain resulting from the bone fragments striking the brain. This article will discuss the subject of short falls in young children and the resulting head injuries. Because falls are frequent events in early life, many cases have been collected and many papers written on the subject. Study of these cases is informative about the injuries likely to occur in these falls. Most often, only a minor contact injury such as scalp bruise or laceration results. In a 2 to 3% of falls, a simple linear skull fracture occurs and the majority of these are uneventful in terms of neurological deficit or intracranial bleeding. In about 1% of the fractures, an epidural or subdural hemorrhage occurs. Each of these forms of contact hemorrhages will be discussed and illustrated. While these are relatively rare injuries, it is essential that they can be identified as consistent with an accidental mechanism so that an erroneous diagnosis of inflicted injury is not made.


Asunto(s)
Accidentes , Lesiones Encefálicas/patología , Fracturas Craneales/patología , Accidentes por Caídas , Accidentes de Tránsito , Factores de Edad , Lesiones Encefálicas/etiología , Lesiones Encefálicas/fisiopatología , Preescolar , Femenino , Hematoma Epidural Craneal/etiología , Hematoma Epidural Craneal/patología , Hematoma Epidural Craneal/fisiopatología , Hematoma Intracraneal Subdural/etiología , Hematoma Intracraneal Subdural/patología , Hematoma Intracraneal Subdural/fisiopatología , Humanos , Lactante , Recién Nacido , Masculino , Cráneo/lesiones , Cráneo/patología , Fracturas Craneales/complicaciones , Fracturas Craneales/etiología
9.
Bioinformation ; 1(10): 390-5, 2007 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-17597928

RESUMEN

The products of five structural genes and two regulatory genes of the qa gene cluster of Neurospora crassa control the metabolism of quinic acid (QA) as a carbon source. A detailed genetic network model of this metabolic process has been reported. This investigation is designed to expand the current model of the QA reaction network. The ensemble method of network identification was used to model RNA profiling data on the qa gene cluster. Through microarray and cluster analysis, genome-wide identification of RNA transcripts associated with quinic acid metabolism in N. crassa is described and suggests a connection to other metabolic circuits. More than 100 genes whose products include carbon metabolism, protein degradation and modification, amino acid metabolism and ribosome synthesis appear to be connected to quinic acid metabolism. The core of the qa gene cluster network is validated with respect to RNA profiling data obtained from microarrays.

10.
Leg Med (Tokyo) ; 9(2): 83-7, 2007 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-17276126

RESUMEN

Abusive head injuries are among the most common causes of serious and lethal injuries in children. These injuries may result from impact or shaking or a combination of these mechanisms. These mechanisms cause the child's head to undergo acceleration-deceleration movements which may create inertial movement of the brain within the cranial compartment. Differential movement between the brain and skull may result in subdural and subarachnoid hemorrhages and traumatic diffuse axonal injury. This paper will discuss the unique anatomical and developmental features of the immature brain, skull, and neck which render young children particularly vulnerable to shearing injuries, the pathology of those injuries, and the mechanisms of these injuries.


Asunto(s)
Maltrato a los Niños/diagnóstico , Traumatismos Craneocerebrales/patología , Niño , Traumatismos Craneocerebrales/diagnóstico , Lesión Axonal Difusa , Humanos , Lactante , Hemorragia Retiniana/etiología , Hemorragia Retiniana/patología , Síndrome del Bebé Sacudido/diagnóstico , Síndrome del Bebé Sacudido/patología , Hemorragia Subaracnoidea Traumática
11.
J AAPOS ; 8(6): 521-7, 2004 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-15616498

RESUMEN

OBJECTIVE: We sought to describe the unique characteristics of children diagnosed with shaken baby syndrome (SBS) despite the absence of intracranial hemorrhage on cranial computerized tomography (CT) on hospital admission. METHODS: Using an international e-mail-based listserv for professionals with an interest in child abuse, we identified and reviewed the charts of children hospitalized in different medical centers who were diagnosed with SBS although CT disclosed no signs of intracranial bleeding. Children with normal imaging were not included. RESULTS: Eight cases were identified. All children had cerebral edema in CT, which was severe on 7/8 cases (88%). All of these children had extensive retinal hemorrhage. The prognosis was poor; 5/8 infants died (63% mortality), and the rest had permanent neurologic damage. CONCLUSION: The diagnosis of SBS can be established even when CT at presentation does not demonstrate intracranial hemorrhage. We hypothesize that rapidly developing cerebral edema may cause increased intracranial pressure and tamponade that prevents the accumulation of intracranial blood. The prognosis in these cases is grave.


Asunto(s)
Hemorragias Intracraneales/diagnóstico por imagen , Síndrome del Bebé Sacudido/diagnóstico por imagen , Tomografía Computarizada por Rayos X , Edema Encefálico/diagnóstico por imagen , Preescolar , Resultado Fatal , Femenino , Humanos , Lactante , Masculino , Pronóstico , Hemorragia Retiniana/diagnóstico
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