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STUDY DESIGN: Narrative review. OBJECTIVE: To provide an overview of the evaluation and diagnosis of degenerative cervical myelopathy (DCM). SUMMARY OF BACKGROUND DATA: DCM describes several etiologies of degenerative, nontraumatic spinal cord impairment. Early diagnosis and intervention can decrease neurological decline. METHODS: An extensive literature review was conducted. RESULTS: The incidence and prevalence of DCM are increasing worldwide. Asymptomatic spinal cord compression can progress to cervical myelopathy. Static and dynamic factors contribute to spinal cord compression. Patients frequently present with decreased manual dexterity, gait instability, and neck pain. On physical exam, patients frequently present with upper motor neuron signs, a Lhermitte sign, a failed Romberg test, global proprioceptive dysfunction, and decreased pain sensation. Anatomic variation may complicate physical exam interpretation. The modified Japanese Orthopaedic Association Scale and Nurick Classification, based on functional impairment, provide diagnostic utility. Magnetic Resonance Imaging imaging is useful in narrowing the differential diagnosis, evaluating the severity of neurological impairment, and predicting disease progression. CONCLUSIONS: Understanding the pathophysiology of DCM and the diagnostic utility of the signs and symptoms of DCM is critical. The decision for anterior cervical discectomy and fusion (ACDF), laminoplasty, or combined ACDF and posterior cervical fusion is individualized for each patient.
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Compresión de la Médula Espinal , Enfermedades de la Médula Espinal , Humanos , Enfermedades de la Médula Espinal/diagnóstico por imagen , Enfermedades de la Médula Espinal/cirugía , Cuello , Dolor de CuelloRESUMEN
Spexin (SPX) and galanin (GAL) are two neuropeptides widely expressed in the central nervous system as well as within peripheral tissues in humans and other species. SPX and GAL mediate their biological actions through binding and activation of galanin receptors (GALR), namely GALR1, GALR2 and GLAR3. GAL appears to trigger all three galanin receptors, whereas SPX interacts more specifically with GALR2 and GLAR3. Whilst the biological effects of GAL have been well-described over the years, in-depth knowledge of physiological action profile of SPX is still in its preliminary stages. However, it is recognised that both peptides play a significant role in modulating overall energy homeostasis, suggesting possible therapeutically exploitable benefits in diseases such as obesity and type 2 diabetes mellitus. Accordingly, although both peptides activate GALR's, it appears GAL may be more useful for the treatment of eating disorders such as anorexia and bulimia, whereas SPX may find therapeutic application for obesity and obesity-driven forms of diabetes. This short narrative review aims to provide an up-to-date account of SPX and GAL biology together with putative approaches on exploiting these peptides for the treatment of metabolic disorders.
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Diabetes Mellitus Tipo 2 , Hormonas Peptídicas , Humanos , Galanina/uso terapéutico , Galanina/farmacología , Receptores de Galanina , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Hormonas Peptídicas/metabolismo , Receptor de Galanina Tipo 2/metabolismo , Obesidad/tratamiento farmacológicoRESUMEN
The Plasma Environment, Radiation, Structure, and Evolution of the Uranian System (PERSEUS) mission concept defines the feasibility and potential scope of a dedicated, standalone Heliophysics orbiter mission to study multiple space physics science objectives at Uranus. Uranus's complex and dynamic magnetosphere presents a unique laboratory to study magnetospheric physics as well as its coupling to the solar wind and the planet's atmosphere, satellites, and rings. From the planet's tilted and offset, rapidly-rotating non-dipolar magnetic field to its seasonally-extreme interactions with the solar wind to its unexpectedly intense electron radiation belts, Uranus hosts a range of outstanding and compelling mysteries relevant to the space physics community. While the exploration of planets other than Earth has largely fallen within the purview of NASA's Planetary Science Division, many targets, like Uranus, also hold immense scientific value and interest to NASA's Heliophysics Division. Exploring and understanding Uranus's magnetosphere is critical to make fundamental gains in magnetospheric physics and the understanding of potential exoplanetary systems and to test the validity of our knowledge of magnetospheric dynamics, moon-magnetosphere interactions, magnetosphere-ionosphere coupling, and solar wind-planetary coupling. The PERSEUS mission concept study, currently at Concept Maturity Level (CML) 4, comprises a feasible payload that provides closure to a range of space physics science objectives in a reliable and mature spacecraft and mission design architecture. The mission is able to close using only a single Mod-1 Next-Generation Radioisotope Thermoelectric Generator (NG-RTG) by leveraging a concept of operations that relies of a significant hibernation mode for a large portion of its 22-day orbit.
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Introduction: Perilunate dislocations and perilunate fracture-dislocations (PLFD) are relatively uncommon injuries, comprising <10% of wrist injuries. Perilunate injuries are often complicated by median neuropathy reported in 23-45% of cases, whereas there are very few reported cases of associated ulnar neuropathy. Combined greater arc and inferior arc injuries are also rare. We report an unusual PLFD pattern with associated inferior arc injury and acute ulnar nerve compression. Case Report: A 34-year-old male sustained a wrist injury after a motorcycle collision. Computed tomography scan revealed a trans-scaphoid, transcapitate, perilunate fracture-dislocation, and a distal radius lunate facet volar rim fracture with radiocarpal subluxation. Examination revealed acute ulnar neuropathy without median neuropathy. He underwent urgent nerve decompression and closed reduction, followed by open reduction internal fixation the next day. He recovered without complication. Conclusion: This case emphasizes the importance of a thorough neurovascular examination to rule out less commonly seen neuropathies. With up to 25% of perilunate injuries misdiagnosed, surgeons should have a low threshold for advanced imaging in high-energy injuries.
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The commonly used consumer product of an ultrasonic humidifier (e.g., cool mist humidifier) emits fine particles containing metals from tap water used to fill the humidifier. The objectives are: 1) predict emitted indoor air inhalable metal concentrations produced by an ultrasonic humidifier filled with tap-water containing As, Cd, Cr, Cu, Mn, and Pb in 33 m3 or 72 m3 rooms with varying air exchange rates; 2) calculate daily ingestion and 8-h inhalation average daily dose (ADD) and hazard quotient (HQ) for adults and children (aged 0.25-6 yr); and 3) quantify deposition in respiratory tract via multi-path particle dosimetry (MPPD) model. Mass concentrations of indoor air metals increase proportionally with aqueous metal concentrations in fill water, and are inversely related to ventilation. Inhalation-ADDs are 2 magnitudes lower than ingestion-ADDs, using identical water quality for ingestion and fill-water. However, in the 33 m3, low 0.2/h ventilated room, inhalation-HQs are >1 for children and adults, except for Pb. HQ inhalation risks exceed ingestion risks at drinking water regulated levels for As, Cd, Cr, and Mn. MPPD shows greater dose deposits in lungs of children than adults, and 3 times greater deposited doses in a 33 m3 vs 72 m3 room. Rethinking health effects of drinking water and consumer products to broaden consideration of multiple exposure routes is needed.
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Contaminación del Aire Interior , Agua Potable , Metales Pesados , Niño , Adulto , Humanos , Contaminación del Aire Interior/análisis , Humidificadores , Calidad del Agua , Cadmio , Ultrasonido , Plomo , Medición de Riesgo , Monitoreo del Ambiente , Metales Pesados/análisisRESUMEN
This systematic review investigates the emissions from ultrasonic humidifiers (e.g., cool mist humidifiers) within indoor air environments, namely soluble and insoluble metals and minerals as well as microorganisms and one organic chemical biocide. Relationships between ultrasonic humidifier fill water quality and the emissions in indoor air are studied, and associated potential adverse health outcomes are discussed. Literature from January 1, 1980, to February 1, 2022, was searched from online databases of PubMed, Web of Science, and Scopus to produce 27 articles. The results revealed clear positive proportional relationships of the concentration of microorganisms and soluble metals/minerals between fill water qualities and emitted airborne particles, for both microbial (n = 9) and inorganic (n = 15) constituents. When evaluating emissions and the consequent health outcomes, ventilation rates of specific exposure scenarios affect the concentrations of emitted particles. Thus, well-ventilated rooms may alleviate inhalation risks when the fill water in ultrasonic humidifiers contains microorganisms and soluble metals/minerals. Case reports (n = 3) possibly due to the inhalation of particles from ultrasonic humidifier include hypersensitivity pneumonitis in adults and a 6-month infant; the young infant exhibited nonreversible mild obstructive ventilator defect. In summary, related literature indicated correlation between fill water quality of ultrasonic humidifier and emitted particles in air quality, and inhalation of the emitted particles may cause undesirable health outcomes of impaired respiratory functions in adults and children.
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Contaminación del Aire Interior , Humidificadores , Lactante , Niño , Humanos , Ultrasonido , Aerosoles , MineralesRESUMEN
Electronic health records (EHRs) have provided physicians with a systematic framework for collecting patient data, organizing notes from the healthcare team, and managing the daily workflow in the modern era of healthcare. Despite these advantages, EHRs have proven to be problematic for clinicians. The burdensome regulations requiring increased documentation with the EHR paradigm have led to inefficiencies from data-entry requirements forcing physicians to spend an inordinate amount of time on it, affecting the time available for direct patient care as well as leading to professional burnout. As a result, new modalities such as speech recognition, medical scribes, pre-made EHR templates, and digital scribes [a form of artificial intelligence (AI) based on ambient speech recognition] are increasingly being used to reduce charting time and increase the time available for patient care. The purpose of our review is to provide an up-to-date review of the literature on these modalities including their benefits and shortcomings, to help physicians and other medical professionals choose the best methods to document their patient-care encounters efficiently and effectively.
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Preterm birth affects more than 10% of all births worldwide. Such infants are much more prone to Growth Faltering (GF), an issue that has been unsolved despite the implementation of numerous interventions aimed at optimizing preterm infant nutrition. To improve the ability for early prediction of GF risk for preterm infants we collected a comprehensive, large, and unique clinical and microbiome dataset from 3 different sites in the US and the UK. We use and extend machine learning methods for GF prediction from clinical data. We next extend graphical models to integrate time series clinical and microbiome data. A model that integrates clinical and microbiome data improves on the ability to predict GF when compared to models using clinical data only. Information on a small subset of the taxa is enough to help improve model accuracy and to predict interventions that can improve outcome. We show that a hierarchical classifier that only uses a subset of the taxa for a subset of the infants is both the most accurate and cost-effective method for GF prediction. Further analysis of the best classifiers enables the prediction of interventions that can improve outcome.
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Microbiota , Nacimiento Prematuro , Humanos , Lactante , Recién Nacido , Recien Nacido Prematuro , Aprendizaje AutomáticoRESUMEN
A complex dataset with 140 sampling events was generated using triple quadrupole gas chromatography-mass spectrometer to track the occurrence of 95 odorants in raw and finished water from 98 drinking water treatment plants in 31 cities across China. Data analysis identified more than 70 odorants with concentrations ranging from not detected to thousands of ng/L. In raw water, Pearson correlation analysis determined that thioethers, non-oxygen benzene-containing compounds, and pyrazines were classes of chemicals that co-occurred, and geosmin and p(m)-cresol, as well as cyclohexanone and benzaldehyde, also co-occurred, indicating similar natural or industrial sources. Based on classification and regression tree analysis, total dissolved organic carbon and geographical location were identified as major factors affecting the occurrence of thioethers. Indoles, phenols, and thioethers were well-removed through conventional and advanced treatment processes, while some aldehydes could be generated. For other odorants, higher removal was achieved by ozonation-biological activated carbon (39.3%) compared to the conventional treatment process (14.5%). To our knowledge, this is the first study to systematically identify the major odorants in raw water and determine suitable treatment strategies to control their occurrence by applying data analytics and statistical methods to the complex dataset. These provide informative reference for odor control and water quality management in drinking water industry.
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Agua Potable , Contaminantes Químicos del Agua , Purificación del Agua , Ciencia de los Datos , Materia Orgánica Disuelta , Odorantes/análisis , Contaminantes Químicos del Agua/análisisRESUMEN
The essential trace element manganese (Mn) can cause neurotoxicity with inhalation acknowledged as a more severe health and cognition threat than ingestion. METHODS: Over a range of aqueous Mn concentrations present in tap water, this research characterizes exposures and risks for adults and 0.25, 1, 2.5, and 6 yr old children who ingest the water and inhale respirable particles produced by a room-sized ultrasonic humidifier filled with the same water. Aqueous Mn concentrations evaluated included 50 µg/L USEPA esthetic guideline, 80 µg/L WHO infant guideline, and 120 µg/L Canadian regulatory level. Airborne-particle-bound Mn concentrations were generated for water filling an ultrasonic humidifier under four realistic room conditions (33 m3 small or 72 m3 large) with varying ventilation rates from 0.2/h -1.5/h. Average daily doses (ADD) and reference intake doses were calculated for ingestion and 8-h inhalation of humidified air. Hazard quotients (HQ) compared the intake doses and reference doses. Multi-path particle dosimetry (MPPD) model quantified the particle deposition and deposited dose in children's and adults' respiratory tracts. RESULTS: At only 11 µg/L Mn, the resulting humidified air Mn exceeds USEPA's reference concentration of 0.05 µg/m3 Mn in small room with low, energy-efficient ventilation. Inhalation ADD are 2 magnitudes lower than ingestion ADD for identical water Mn concentrations and daily exposure frequency. Even so, ingestion HQs are approximately 0.2 but inhalation risk is significant (HQ>1) for children and adults when breathing Mn-humidified air under most small room conditions at 50, 80 or 120 µg/L Mn. MPPD model indicates inhaled Mn deposits in head and pulmonary regions, with greater Mn dose deposits in children than adults. CONCLUSION: Inhalation of Mn-particles produced from ultrasonic humidifiers can pose greater risks than ingestion at the same water concentration, especially for children. Aqueous Mn concentration and room size influence risks. Limiting manganese exposures and setting regulations requires consideration of both ingestion and inhalation of water.
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Humidificadores , Manganeso , Adulto , Canadá , Niño , Ingestión de Alimentos , Humanos , Lactante , Exposición por Inhalación/análisis , Ultrasonido , AguaRESUMEN
Room-sized ultrasonic humidifiers are exposure pathways to aerosolized metals, with dose positively associated with increased concentrations of metals in fill water. This study innovatively quantifies water ingestion along with inhalation doses from humidifiers for 10-1000 µg/L dissolved lead (Pb) in tap water. The subsequent indoor air Pb concentrations, average daily doses, and inhalation deposited respiratory fractions were predicted under four room scenarios for 3-mo, 12-mo, 28-mo, and 6-yr children and adults. Elevated blood Pb levels (BLLs) in children were modeled using USEPA's Integrated Exposure Uptake Biokinetic (IEUBK) model. Indoor air Pb exceeds the USEPA ambient air standard of 0.15 µg/m3 when humidifier fill water contains 33 µg/L Pb in the small room of 33.5 m3 and 0.2 h-1 air exchange rate (AER). For this room, ~40-46% inhaled Pb-containing humidifier particles deposit in children's respiratory tracts; inhaling humidifier particles from ≥500 µg/L Pb water results in >1 µg/dL BLL in 2-7 yr children. For adults, ~23% of particles deposit in the respiratory tract; 8-h inhalation exposure with ≥17 µg/L Pb water exceeds the California EPA reproductive toxicity guideline of 0.5 µg/day. Larger rooms and higher AER decrease Pb inhalation exposure under the same water Pb concentration.
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Humidificadores , Plomo , Adulto , Niño , Ingestión de Alimentos , Humanos , Ultrasonido , AguaRESUMEN
Salmonella, Shiga toxin-producing Escherichia coli (STEC), and Listeria monocytogenes have been isolated from low water activity foods (LWAF), where they may survive for extended periods. The ready-to-eat nature of many LWAF, such as dried fruits and nuts, warrants effective post-harvest thermal treatment for the reduction of pathogens such as low-temperature, saturated steam, also known as vacuum-assisted steam pasteurization. The objective of this study was to determine reductions of Salmonella, STEC, L. monocytogenes, and a possible surrogate (Pediococcus acidilactici) on dried apricot halves, whole macadamia nuts, and raisins after treatment with vacuum-assisted steam at three temperatures (62 °C, 72 °C, or 82 °C) and multiple time intervals. Bacterial inactivation was variable between commodities, with higher temperatures and longer times necessary to achieve comparable reductions of pathogens on apricot halves and macadamia nuts compared to raisins. Reductions of the tested pathogens were comparable; therefore, one species was not more resistant than the others. Pathogens were reduced by 5-log CFU/g on apricot halves after 20 min at 72 °C and after 5 min at 82 °C. Longer treatment times were necessary to achieve reductions of each pathogen on macadamia nuts. Pathogens were reduced by nearly 5 log CFU/g on macadamia nuts after 38 min at 72 °C (4.6-6.5 log CFU/g) and after 12 min at 82 °C (4.9-5.7 log CFU/g). Reductions of pathogens on raisins were achieved at lower temperatures than necessary for the other foods. A 5-log reduction for each of the pathogens (CFU/g) on raisins occurred after 20 min at 62 °C and after 5 min at 72 °C. Overall, the reductions of the pathogens exceeded those of P. acidilactici on both the dried fruits and macadamia nuts. Statistically significant differences, indicating greater confidence as a conservative surrogate, were observed at lower treatment temperatures. Inactivation kinetics were modeled for each pathogen on each food type and temperature. Bacterial survival was best described by the Weibull model for raisins and macadamia nuts, while the Gompertz model best described reductions on apricot halves according to Akaike information criterion (AIC) and root-mean-square error (RMSE) evaluations. Water activity and moisture content were increased due to the treatments, which could be addressed through implementation of drying steps. Thermal inactivation kinetic models and 5-log reduction parameters can help food processors design and evaluate similar vacuum-assisted steam interventions to comply with FSMA regulations and preventive control plans. However, results or model predictions should not be extrapolated to assume the safety of other types of foods.
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Bacterias/aislamiento & purificación , Macadamia/microbiología , Pasteurización/métodos , Prunus armeniaca/microbiología , Vitis/microbiología , Bacterias/crecimiento & desarrollo , Microbiología de Alimentos , Calor , Listeria monocytogenes/aislamiento & purificación , Nueces , Pediococcus acidilactici/aislamiento & purificación , Salmonella/aislamiento & purificación , Escherichia coli Shiga-Toxigénica/aislamiento & purificación , Vapor , VacioRESUMEN
Fine particulates and aerosols emitted by commonly used, room-sized ultrasonic humidifiers may pose adverse health effects to children and adults. The literature documents adverse effects for children exposed to minerals emitted from humidifiers. This study performs novel and comprehensive characterization of bivariate particle size and element concentrations of emitted airborne aerosols and particles from ultrasonic humidifiers filled with tap water, including size distribution from 0.014 to 10 µm by scanning mobility particle sizer and AeroTrak; corresponding metal and elemental concentrations as a function of particle size by inductively coupled plasma mass spectrometer; and calculations of deposition fraction in human lungs for age-specific groups using the multi-path particle dosimetry model (MPPD). Deposition fraction is the ratio of mass deposited to total mass inhaled. When filled with tap water, water evaporated from emitted aerosols to form submicron particles that became essentially "dried tap water" with median size 146 nm and mean concentration of 211 µg-total elements/m3-air including 35 µg-calcium/m3-air in a room of 33.5 m3 and air exchange rate at â¼0.8 hr-1. Approximately 90% of emitted particles deposited in human lungs were <1 µm as shown by MPPD model. The smaller particles contained little water and higher concentration of minerals, while larger particles of >1 µm consisted of lower elemental concentrations and more water due to low evaporation. Deposition fraction in pulmonary region was â¼2-fold higher, and deposited particulate mass was 3.5-fold higher for children than adults, indicating greater inhalation exposure to children compared to adults. Modeled data of total particles mass per body weight (BW) that will deposit in adult and child lungs after 8-h humidifier exposure were respectively 2.8 µg/kg-BW and 9.8 µg/kg-BW, where calcium contributes 0.4 µg/kg-BW and 1.6 µg/kg-BW. This comprehensive study of bivariate inorganic chemical composition as a function of particle size expanded, quantified, and modeled exposure for children and adults to aerosolized calcium and other inorganic constituents in water.
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Drinking water supplied by private wells is a national concern that would benefit from improved outreach and support to ensure safe drinking water quality. In North Carolina (NC), local health departments (LHDs) have private well programs that enforce statewide well construction standards, offer water testing services, and provide well water outreach and assistance. Programs were evaluated to determine their capacity and capability for well water outreach and assistance and identify differences among programs. All LHDs reported overseeing the construction of new wells as required by law. However, services provided to existing well users were offered infrequently and/or inconsistently offered. Lack of uniformity was observed in the number of LHD staff and their assigned responsibilities; the costs and availability of well water testing; and the comfort of LHD staff communicating with well owners. While the total number of staff was lower in LHDs in rural counties, the number of outreach activities and services offered was typically not related to the number of well users served. Variations in structure and capacity of well programs at LHDs have created unequal access to services and information for well users in NC. This research underscores the need to examine infrastructure that supports the well water community on a national scale.
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Pozos de Agua , Agua , Humanos , North Carolina , Factores Socioeconómicos , Calidad del AguaRESUMEN
Ultrasonic humidifiers provide indoor relief to symptoms caused by dry air and produce aerosols containing both water and minerals that are present in the water that fills the humidifier. This study investigated the spatial distributions, concentrations, and metal and mineral composition of aerosols emitted when an ultrasonic humidifier was filled with deionized water (DI), low mineral tap water (LL), high total dissolved solids (TDS)/high hardness water (HH), and high TDS/low hardness water (HL). Aerosol/particle sizes and counts were obtained at six horizontal distances in both the plume and near floor for each water quality. Results are that water quality significantly affects particle size distributions which become uniform after 0.9 m from the humidifier outlet, and are independent of vertical distance from the humidifier. The mean count median diameters were 64 nm for DI, 129 nm for LL, 234 nm for HH, and 260 nm for HL; the particle counts and total mineral solids concentrations were 2,194 #/cm3 (16 µg/m3) for DI, 21,070 #/cm3 (113 µg/m3) for LL, 38,353 #/cm3 (438 µg/m3) for HH, and 43,880 #/cm3 (521 µg/m3) for HL. The µg/m3 values for LL, HH, and HL exceeded PM2.5 ambient air standards. Model predictions are that the deposition mass in the human respiratory system from inhaling particles emitted from HH and HL water exceed 135 µg for a 1 to 3-month old child and 600 µg for an adult over an 8-hr period. Mineral water quality significantly affects the distribution and concentration of emitted and inhaled indoor air particles. Consumers may unknowingly be degrading their indoor air quality when using tap water of acceptable drinking water quality as humidifier fill water.
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Contaminantes Atmosféricos , Contaminación del Aire Interior , Adulto , Contaminantes Atmosféricos/análisis , Contaminación del Aire Interior/análisis , Niño , Monitoreo del Ambiente , Humanos , Humidificadores , Lactante , Tamaño de la Partícula , Material Particulado , Ultrasonido , Agua , Calidad del AguaRESUMEN
To characterize human emotions, researchers have increasingly utilized Automatic Facial Expression Analysis (AFEA), which automates the Facial Action Coding System (FACS) and translates the facial muscular positioning into the basic universal emotions. There is broad interest in the application of FACS for assessing consumer expressions as an indication of emotions to consumer product-stimuli. However, the translation of FACS to characterization of emotions is elusive in the literature. The aim of this systematic review is to give an overview of how FACS has been used to investigate human emotional behavior to consumer product-based stimuli. The search was limited to studies published in English after 1978, conducted on humans, using FACS or its action units to investigate affect, where emotional response is elicited by consumer product-based stimuli evoking at least one of the five senses. The search resulted in an initial total of 1,935 records, of which 55 studies were extracted and categorized based on the outcomes of interest including (i) method of FACS implementation; (ii) purpose of study; (iii) consumer product-based stimuli used; and (iv) measures of affect validation. Most studies implemented FACS manually (73%) to develop products and/or software (20%) and used consumer product-based stimuli that had known and/or defined capacity to evoke a particular affective response, such as films and/or movie clips (20%); minimal attention was paid to consumer products with low levels of emotional competence or with unknown affective impact. The vast majority of studies (53%) did not validate FACS-determined affect and, of the validation measures that were used, most tended to be discontinuous in nature and only captured affect as it holistically related to an experience. This review illuminated some inconsistencies in how FACS is carried out as well as how emotional response is inferred from facial muscle activation. This may prompt researchers to consider measuring the total consumer experience by employing a variety of methodologies in addition to FACS and its emotion-based interpretation guide. Such strategies may better conceptualize consumers' experience with products of low, unknown, and/or undefined capacity to evoke an affective response such as product prototypes, line extensions, etc.
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The presence of earthy-musty odors in drinking water is a major concern for water suppliers and consumers worldwide. While geosmin and 2-methylisoborneol are the most studied earthy-musty odor-causing compounds, pyrazine and its alkyl and methoxy compounds possess similar odors and are widely distributed in nature, foods, and beverages. In this study, odor characteristics of pyrazines and their presence in natural and treated waters were determined. Pyrazine, 2,6-dimethyl-pyrazine (DMP), 2,3,5-trimethyl-pyrazine (TrMP), 2-ethyl-5(6)-methyl-pyrazine (EMP), 2,3,5,6-tetramethyl-pyrazine (TeMP), 2-isobutyl-3-methoxy-pyrazine (IBMP) and 2-isopropyl-3-methoxy-pyrazine (IPMP) were measured in source and finished drinking water across China. 2-Methoxy-3,5-dimethyl-pyrazine (MDMP), IBMP, and IPMP were investigated in rivers in Virginia, USA. The results showed that "musty" and "sweet" were the most common descriptors for pyrazine, DMP, MDMP, TrMP, and TeMP. While IBMP and IPMP were never detected in 140 source or drinking water samples from across China, pyrazine, DMP, MDMP, TrMP, and TeMP occurred throughout with concentrations of n.d.-62.2 ng/L-aq in source water and n.d.-39.6 ng/L-aq in finished water. IBMP, IPMP, and MDMP were present in two Virginia rivers; MDMP occurred in 18% of the samples with concentrations of n.d.-4.4 ng/L, many of which were above the aqueous odor threshold of 0.043 ng/L MDMP. The removal efficiencies through conventional water treatment were poor, ranging from negative removals to â¼10%. Advanced oxidation water treatment could only remove EMP and TrMP. The widespread presence of earthy-musty-sweet pyrazines in source and drinking waters on two continents, their poor removal during water treatment, and ng/L odor threshold concentrations confirm their potential to be T&O issues for consumers.
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Agua Potable , Contaminantes Químicos del Agua/análisis , China , Comportamiento del Consumidor , Odorantes/análisis , Pirazinas/análisis , VirginiaRESUMEN
Ultrasonic humidifier use is a potential source of human exposure to inhalable particulates. This research evaluated the behavior of insoluble iron oxide and aluminum oxide particles in water used to fill room-sized ultrasonic humidifiers. Solutions of 10â¯mg/L Fe, as iron oxide particles, or 5â¯mg/L Al, as aluminum oxide suspension, were added into tap water used to fill ultrasonic humidifiers. The humidifiers were operated for 14â¯h; samples were obtained over time and monitored for soluble and particulate Fe and Al, as well as particle sizes in the humidifier reservoir and emitted in aerosols. Denser, settleable particles of approximately 1.5⯵m diameter of iron or aluminum oxides accumulated at the bottom of the humidifier reservoir. Smaller, suspended metal oxide particles of 0.22-0.57⯵m diameter were emitted as aerosols from the humidifier. Soluble anions and cations in tap water were also present in the aerosols emitted from humidifiers. The results indicate that a typical 1.6â¯MHz ultrasonic humidifier can emit 0.22-0.57⯵m particles and dissolved minerals from fill water into breathable air.
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Humidificadores , Ultrasonido , Aerosoles , Aluminio , Óxido de Aluminio , Humanos , HierroRESUMEN
Various antimicrobial interventions are applied sequentially in the beef processing industry to reduce microbial load on beef products by using intensive inputs (e.g., chemicals, energy), high strength wastewater, and potentially result in meat discoloration. This study serves as the first analysis to jointly evaluate environmental and economic assessment with its microbial load reduction of proposed antimicrobial systems in the U.S. beef processing industry to identify relatively sustainable systems that minimize environmental and economic impacts while providing microbial safe meat. Specifically, forty potential sequential antimicrobial systems were proposed and evaluated from three perspectives: microbial load reduction, environmental, and economic impacts, by meta-analysis, life cycle assessment, and operational cost analysis orderly. The results show that the antimicrobial systems applying steam pasteurization during the main intervention offer high microbial load reduction (>4.2â¯logâ¯CFU/cm2 reduction from a hypothetical initial contamination at 5.0â¯logâ¯CFU/cm2). Human health impact (31.0 to 65.6%) and ecosystem toxicity (3.6 to 12.5%), eutrophication (11.9 to 15.5%) and global warming (6.4 to 22.2%) are the main contributors to the overall environmental single score among the forty antimicrobial systems. Antimicrobial chemicals (up to 82.8%), wastewater treatment (up to 12.7%), and natural gas (up to 10.7%) are the three major drivers of operational cost for sanitizing 1000â¯kg hot standard carcass weight (HSCW). Devalued (discolored) meat due to contact with heat from steam pasteurization or hot water wash has a considerable increase in economic ($4.5/1000 HSCW) and environmental (especially at farm stage) impacts. Certain antimicrobial systems (e.g., water wash followed by steam pasteurization) were found to be more promising with satisfactory effectiveness, better environmental and cost performance under uncertainty (1000 Monte Carlo simulations). Results from this study can guide the U.S. beef processing industry to advance sustainability while protecting human health from foodborne illness.
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Manipulación de Alimentos/métodos , Microbiología de Alimentos , Carne Roja , Mataderos , Animales , Antiinfecciosos , Bovinos , Seguridad de Productos para el Consumidor , Manipulación de Alimentos/estadística & datos numéricos , Enfermedades Transmitidas por los Alimentos , HumanosRESUMEN
Benzene, toluene, ethylbenzene, and xylenes (BTEX) are hazardous air pollutants commonly found in outdoor air. Several studies have explored the potential of vegetation to mitigate BTEX in outdoor air, but they are limited to a northern temperate climate and their results lack consensus. To investigate this subject in a subtropical climate, we deployed passive air samplers for two weeks in parks and outside nearby residences at four locations: three in an urban area and one in a rural area in Alabama, USA. All BTEX concentrations were below health-based guidelines and were comparable to those found in several other studies in populated settings. Concentrations of TEX, but not benzene, were 3-39% lower in parks than at nearby residences, and the differences were significant. Site type (park vs. residential) was a significant predictor of TEX concentrations, while distance to the nearest major road was a significant predictor of BTX concentrations. In and around two of the parks, toluene : benzene ratios fell outside the range expected for vehicular emissions (p < 0.01), suggesting that there were additional, industrial sources of benzene near these two locations. The ratio of m-,p-xylene : ethylbenzene was high at all locations except one residential area, indicating that BTEX were freshly emitted. Concentrations of individual BTEX compounds were highly correlated with each other in most cases, except for locations that may have been impacted by nearby industrial sources of benzene. Results of this study suggest that parks can help reduce exposure to TEX by a modest amount in some situations.