Development of a test method to measure in-use emissions from stationary and portable diesel sources

A cost-effective, accurate and easy-to-use in-field test method was developed that would allow regulatory bodies, such as the California Air Resources Board (CARB) to determine in-use compliance with emission standards for newly manufactured portable and stationary engines. As emissions measured during an engine-dynamometer test do not faithfully reflect real-world emissions, a test method that functions like an Inspection and Maintenance (I/M) type test method was developed. Only concentration measurements of pollutants such as oxides of nitrogen (NO x) and carbon dioxide (CO2) are required to determine compliance using this compliance factor, F approach. Hence, errors introduced due to engine work output measurement and exhaust flow rate measurement are avoided.;A compliance factor F, defined as the ratio of in-use concentrations NOx and CO2 to the manufacturer reported brake specific emissions of NOx and CO2 was developed and its application is illustrated in multiple ISO 8178 tests on mechanically and electronically controlled engines. Raw exhaust emissions were measured using a Mobile Emission Measurement System (MEMS) and a Method 5 system, and correlated with the constant volume sampling (CVS) measurements that were performed in accordance with the regulatory requirements. It was determined that the front-half of the Method 5 particulate matter (PM) measurement methodology is in good agreement with the CVS system. Further, a modified Method 5 sampling train comprising of a multi-hole sampling probe that spans the diameter of the exhaust stack, and a sample transfer tube maintained at ambient temperature could be a likely configuration for measuring PM from stationary and portable diesel engines operating in the field

Nondestructive evaluation of FRP composite members using infrared thermography

The objective of this research is to establish infrared thermography as an effective tool for nondestructive evaluation of structural members made of fiber reinforced polymer (FRP) composite materials. The applicability of this method for the detection of subsurface anomalies such as voids, cracks, debonding, and delaminations in concrete bridge decks and pavements and in some configurations of FRP decks has been studied earlier by other researchers. These earlier studies have yielded reasonably satisfactory results though further refinement of the methodology and improvements in the image processing techniques were recommended.;To enhance the effectiveness of the infrared thermography technique, it is important to improve and quantify the contrast in the thermal images. This enables the thermographer to arrive at better conclusions including quantitative estimation of the defect depth. Different methods for analysis of digital infrared images suggested by various researchers were reviewed in this study and recommendations were made for evaluating their applicability for mass-produced FRP composite structural components.;Infrared thermography tests were conducted in the laboratory on various FRP specimens with built-in delaminations. The results showed that the infrared technique can be developed for long term monitoring of FRP structural components. As a part of this research, a field trip was also conducted for detecting the presence of delaminations/debondings in FRP wrapped reinforced concrete bridge columns using infrared thermography. In the field tests, it was possible to detect the locations of delaminations/debondings. These results were in agreement with the tapping test results

Cutaneous Squamous Cell Carcinoma of the Head and Neck

Cutaneous squamous cell carcinoma of the head and neck is an epidemic that reaches all parts of the world. Making the diagnosis relies on the acumen of the clinician and pathologist. Various pathologic subtypes exist and differ in histology and prognosis. High-risk tumors need aggressive treatment and vigilant surveillance to monitor for recurrence. Large tumors, deep tissue invasion, perineural involvement, recurrence, location in high-risk areas, and immunosuppression are implicated in worsening prognosis. Surgery is the mainstay of treatment with adjuvant radiation therapy as needed for aggressive tumors; however, other modalities are potentially useful for low-risk lesions. The use of Mohs surgery has become increasingly useful and has shown high success rates. Involvement of parotid and neck lymph nodes significantly affects outcomes and the physician should be comfortable with management of this complex disease. This paper examines the diagnosis, pathology, clinical course, and treatment options for cutaneous squamous cell carcinoma of the head and neck

Maternal Immune Activation Causes Behavioral Impairments and Altered Cerebellar Cytokine and Synaptic Protein Expression

Emerging epidemiology studies indicate that maternal immune activation (MIA) resulting from inflammatory stimuli such as viral or bacterial infections during pregnancy serves as a risk factor for multiple neurodevelopmental disorders including autism spectrum disorders and schizophrenia. Although alterations in the cortex and hippocampus of MIA offspring have been described, less evidence exists on the impact on the cerebellum. Here, we report altered expression of cytokines and chemokines in the cerebellum of MIA offspring, including increase in the neuroinflammatory cytokine TNFα and its receptor TNFR1. We also report reduced expression of the synaptic organizing proteins cerebellin-1 and GluRδ2. These synaptic protein alterations are associated with a deficit in the ability of cerebellar neurons to form synapses and an increased number of dendritic spines that are not in contact with a presynaptic terminal. These impairments are likely contributing to the behavioral deficits in the MIA exposed offspring

Methamphetamine and Inflammatory Cytokines Increase Neuronal Na+/K+-ATPase Isoform 3: Relevance for HIV Associated Neurocognitive Disorders

Methamphetamine (METH) abuse in conjunction with human immunodeficiency virus (HIV) exacerbates neuropathogenesis and accelerates neurocognitive impairments in the central nervous system (CNS), collectively termed HIV Associated Neurocognitive Disorders (HAND). Since both HIV and METH have been implicated in altering the synaptic architecture, this study focused on investigating alterations in synaptic proteins. Employing a quantitative proteomics approach on synaptosomes isolated from the caudate nucleus from two groups of rhesus monkeys chronically infected with simian immunodeficiency virus (SIV) differing by one regimen, METH treatment, we identified the neuron specific Na+/K+-ATPase alpha 1 isoform 3 (ATP1A3) to be up regulated after METH treatment, and validated its up regulation by METH in vitro. Further studies on signaling mechanisms revealed that the activation of ATP1A3 involves the extracellular regulated kinase (ERK) pathway. Given its function in maintaining ionic gradients and emerging role as a signaling molecule, changes in ATP1A3 yields insights into the mechanisms associated with HAND and interactions with drugs of abuse

Moya Moya Disease: Presenting With Changing Neurological Signs

A 4 yrs old female child was admitted with left hemiparesis and unconsciousness and a short history of neurological impairment, changing neurological signs with progress of the disease and most of relevant laboratory investigations being normal, child underwent MRI and MRA which revealed features of Moya moya disease

Investigation of indentation size effects in elastomers

Indentation tests were performed on polydimethylsiloxane and natural rubber as two highly elastic materials at the micronanometer indentation depths to investigate the underlying depth dependent deformation of polymers at such length scales. It was observed that the deformation mechanisms at these small length scales are significantly different when compared with the mechanisms at macroscopic length scales. For both polymers, experimental results exhibited strong size effects with a very strong increase in the universal hardness for small indentation depths which cannot be predicted by the classical local continuum elasticity theory. These strong size effects were analyzed by a depth dependent hardness model (motivated by Frank energy type mechanisms incorporating rotation gradients) where good agreement was achieved between the experiments and the theoretical hardness model. Compared to other polymers in the glassy state, however, the indentation size effect in the elastomers was much stronger. The chains of polymers in the elastomers and other polymers in rubbery state have increased mobility to rotate resulting in a more pronounced rotation gradient part in the total deformation energy density of the polymer. According to this rationale, the indentation size effects should be significantly stronger in rubbers and other polymers in rubbery state, when compared with glassy polymers

Therapeutic Potential of Suvorexant on Intergenerational Maternal Oxycodone Exposure

Background: Maternal opioid misuse is a rising public health concern. Our lab previously published findings that in-utero oxycodone exposure (IUO) has detrimental impacts that persist to the F2 generation, including abnormal genetic expression, increased anxiety, and a difference in phenotypic measurements. The estimated cost of hospital admissions for infants suffering from Neonatal Abstinence Syndrome was $316 million in 2012 and is still rising. This figure does not take into account long-term costs, nor does it consider lasting effects on the F2 generation. Thus, it is critical to find a way to mitigate the negative impacts of IUO. Suvorexant (suvo) is a dual hypocretin receptor antagonist that is FDA-approved for the treatment of insomnia. The hypocretin system is involved in the regulation of the sleep/wake cycle, feeding behavior, and notably, addiction. Our previous findings showed that Hcrtr1 is upregulated in both F1 and F2 IUO offspring. This project will test the therapeutic potential of suvorexant to attenuate the impacts of IUO. Hypothesis: The administration of suvorexant on F1 animals that have been subjected to IUO will result in the alleviation of developmental impairments in the F2 generation. Methods: Female Sprague Dawley rats in the F0 generation were orally gavaged with 15mg/kg oxycodone or equal volumes of saline. Dosing was maintained from mating until weaning at post-natal day 21 (P21). F1 animals were given ascending doses of suvorexant (3mg/kg P3-P6, 10mg/kg P7-P10, 30mg/kg P11-P21) or an equal volume of DMSO through subcutaneous injection. At P60, 2 females from each condition were mated with naïve breeders. Phenotypic measurements of the F2 generation including weight, head size circumference, and body length were taken at P3 and P14. At P21, 6-8 animals were sacrificed, and organs were collected. Social preference/novelty tests were conducted at P28 and P45. The next phase of this study will consist of molecular assays, imaging, and further behavior testing including an oxycodone self-administration study. Results: Our preliminary results showed that F2 IUO-Suvo animals exhibited significant differences in body weight, body length, and head size circumference at P7 and P14 compared to the control. Furthermore, in the social preference test, the IUO-Suvo animals had significantly more entries into both the toy and naïve chambers at P45, as well as significantly more contacts with both the toy and naïve animal at P28. Conclusions: Administering suvorexant in the F1 generation may mitigate physical and behavioral deficits in the F2 generation caused by intergenerational IUO.https://digitalcommons.unmc.edu/chri_forum/1066/thumbnail.jp