Pickup (critical) velocity of particles

This work presents experimental results on pickup velocity (critical velocity) measurements for a variety of particulate solids. The present experiments together with previously published experiments of a number of researchers encompass about 100 measurements of 24 materials for a wide range of particle sizes, shapes and densities. Based on the experimental results, three zones are defined by establishing simple relationships between the Reynolds and Archimedes numbers. The empirical relationships were further modified by taking into account the pipe diameter and particle shape (sphericity). The three-zone model was shown to reasonably correlate to Geldart's classification groups.     

Resisting tempting foods and smoking behavior: Implications from a self-control theory perspective.

Objective: Individuals may desire to diet or restrain from eating certain foods while attempting to quit smoking out of concern for weight gain. However, previous research and clinical tobacco treatment guidelines suggest that concurrent dieting may undermine attempts to quit smoking. The current study applied the self-control strength model, which posits that self-regulation relies on a limited strength that is consumed with use, to test whether resisting tempting sweets would lead to a greater likelihood of subsequent smoking. Design: Participants were 101 cigarette smokers randomly assigned to resist eating either from a tempting plate of sweets or from a plate of less tempting vegetables. All participants were then given a 10-min recess. Main Outcome Measures: Whether participants smoked during the break, measured with a breath carbon monoxide sample, served as the primary dependent variable. Results: As predicted, participants who resisted sweets were more likely to smoke during the break (53.2%) than those who resisted vegetables (34.0%), χ2(1, N = 101) = 3.65 p     

Maternal N-Acetyl-Cysteine Prevents Neonatal Hypoxia-Induced Brain Injury in a Rat Model

Perinatal hypoxia is a major cause of infant brain damage, lifelong neurological disability, and infant mortality. N-Acetyl-Cysteine (NAC) is a powerful antioxidant that acts directly as a scavenger of free radicals. We hypothesized that maternal-antenatal and offspring-postnatal NAC can protect offspring brains from hypoxic brain damage.Sixty six newborn rats were randomized into four study groups. Group 1: Control (CON) received no hypoxic intervention. Group 2: Hypoxia (HYP)-received hypoxia protocol. Group 3: Hypoxia-NAC (HYP-NAC). received hypoxia protocol and treated with NAC following each hypoxia episode. Group 4: NAC Hypoxia (NAC-HYP) treated with NAC during pregnancy, pups subject to hypoxia protocol. Each group was evaluated for: neurological function (Righting reflex), serum proinflammatory IL-6 protein levels (ELISA), brain protein levels: NF-κB p65, neuronal nitric oxide synthase (nNOS), TNF-α, and IL-6 (Western blot) and neuronal apoptosis (histology evaluation with TUNEL stain). Hypoxia significantly increased pups brain protein levels compared to controls. NAC administration to dams or offspring demonstrated lower brain NF-κB p65, nNOS, TNF-α and IL-6 protein levels compared to hypoxia alone. Hypoxia significantly increased brain apoptosis as evidenced by higher grade of brain TUNEL reaction. NAC administration to dams or offspring significantly reduce this effect. Hypoxia induced acute sensorimotor dysfunction. NAC treatment to dams significantly attenuated hypoxia-induced acute sensorimotor dysfunction. Prophylactic NAC treatment of dams during pregnancy confers long-term protection to offspring with hypoxia associated brain injury, measured by several pathways of injury and correlated markers with pathology and behavior. This implies we may consider prophylactic NAC treatment for patients at risk for hypoxia during labor.     

Water remediation by micelle-clay system: case study for tetracycline and sulfonamide antibiotics

Removal of tetracycline and sulfonamide antibiotics from water by micelles pre-adsorbed on montmorillonite was studied. Micelles of benzyldimethylhexadecylammonium (BDMHDA) were used. Batch experiments demonstrated that the micelle-clay complexes (1% w/w) removed 96-99.9% of antibiotics from their water solutions containing from 5 to 50 mg/L of pharmaceuticals. Column filters (25 cm) made of a mixture of quartz sand and BDMHDA micelle-clay complex at 100:1 w/w ratio removed 94-99.9% of above pharmaceuticals from initial solutions containing 10mg/L and 89% of sulfamethizole from an initial solution containing 10 microg/L of this antibiotic. These filters were also very efficient in the removal of antibiotics in the presence of dissolved soil organic matter removing 89-99% of tetracycline and sulfamethizol from initial solutions containing 10 mg/L of antibiotic in the presence of 8 mg/L of humic acid, or 9 mg/L of fulvic acid. These data indicate that micelle-clay complexes are very efficient for water purification from tetracycline and sulfonamide antibiotics.     

Changes in psychiatric patients' thoughts about quitting smoking during a smoke-free hospitalization.

Though exempted from national bans of tobacco smoking in hospitals, some psychiatric facilities have voluntarily gone 100% smoke free with little reported difficulty in clinical management. The impact of smoking restrictions on psychiatric patients' thoughts about quitting smoking, however, is not known. This study investigates changes in thoughts about quitting smoking for patients hospitalized in a smoke-free psychiatric inpatient facility. Participants were 100 smokers recruited from a university-based adult inpatient psychiatry unit. The present study focused on participants' reported desire to quit smoking, their expectancy of success and anticipated difficulty with quitting, and their smoking abstinence goal. Assessments were conducted at hospital intake and shortly before hospital discharge. Follow-up assessments were conducted by phone at 1 week, 1 month, and 3 months post-hospitalization to measure smoking behavior. Although no cessation treatment was provided in this observational study, from admission to discharge, participants reported an increased expectancy of success with quitting and a decreased expectancy of difficulty with staying quit. They also were more likely to endorse a smoking-related goal. Psychiatric diagnosis was not related to thoughts about abstinence. Furthermore, participants' thoughts about abstinence at discharge were significantly related to their subsequent smoking behavior. Hospitalization in a smoke-free environment is associated with increases in patients' expectancies about quitting and staying smoke free.     

Atrazine removal from water by polycation-clay composites: Effect of dissolved organic matter and comparison to activated carbon

Atrazine removal from water by two polycations pre-adsorbed on montmorillonite was studied. Batch experiments demonstrated that the most suitable composite poly (4-vinylpyridine-co-styrene)-montmorillonite (PVP-co-S90%-mont.) removed 90-99% of atrazine (0.5-28 ppm) within 20-40 min at 0.367% w/w. Calculations employing Langmuir's equation could simulate and predict the kinetics and final extents of atrazine adsorption. Column filter experiments (columns 20 × 1.6 cm) which included 2 g of the PVP-co-S90%-mont. composite mixed with excess sand removed 93-96% of atrazine (800 ppb) for the first 800 pore volumes, whereas the same amount of granular activated carbon (GAC) removed 83-75%. In the presence of dissolved organic matter (DOM; 3.7 ppm) the efficiency of the GAC filter to remove atrazine decreased significantly (68-52% removal), whereas the corresponding efficiency of the PVP-co-S90%-mont. filter was only slightly influenced by DOM. At lower atrazine concentration (7 ppb) the PVP-co-S90%-mont. filter reduced even after 3000 pore volumes the emerging atrazine concentration below 3 ppb (USEPA standard). In the case of the GAC filter the emerging atrazine concentration was between 2.4 and 5.3 μg/L even for the first 100 pore volumes. Thus, the PVP-co-S90%-mont. composite is a new efficient material for the removal of atrazine from water.     

Forcing a cis-Product by Matrix Imprinting: Heck Reaction Catalyzed by Palladium Acetate Entrapped within cis-Imprinted Sol-Gel Derived Silicates

While the Heck coupling of aryl bromides with styrenes by palladium acetate entrapped within octylated silica sol-gel forms almost entirely trans-stilbenes, the catalysis by the palladium compound within the cis-pre-imprinted support gives stilbenes that are substantially enriched by cis-oriented isomers. Although the ceramic support is completely freed from the imprint prior to the coupling process, cis-stilbenes are formed with similar selectivities upon recycling of the catalyst systems for at least four consecutive runs.     

Enhanced removal of humic acid from water by micelle-montmorillonite composites: Comparison to granulated activated carbon

Removal of humic acid (HA) from water by octadecyltrimethyl-ammonium (ODTMA) micelle–montmorillonite (MMT) composites and by granulated activated carbon (GAC) was studied in dispersion and by filtration. FTIR measurements emphasized that the ODTMA micelle–clay-mineral composite differs from the ODTMA monomer-clay-mineral one. HA adsorption by GAC in dispersion was moderately reduced from 100% initially to 75% with an increase in HA concentrations. In contrast, the fractions adsorbed by the composite increased monotonically with HA concentrations from very low adsorption up to 80%. This effect was explained by the presence of a small concentration of ODTMA monomers in dispersion, which adsorbed on the negatively charged HA and partially neutralized it, or caused charge reversal, which in turn inhibited HA adsorption by the positively charged composite. This effect was verified by mobility measurements and was found to be more pronounced at low HA concentrations. This trend of increase in HA removal with an increase in HA concentration (3 and 10 ppm) was also observed in filtration (50% and 85% removal, respectively), when employing columns of the composite mixed with sand (to improve flow). Throughout the experiment the removal of high HA concentration (10 ppm) by the composite filter remained ~ 80% whereas, the removal by the GAC filter decreased from an initial 80% removal to a complete recovery of the HA (no removal) after the passage of 20 L (200 pore volumes). Upon applying sand of higher quality in the columns the removal of low HA concentrations was nearly complete by the composite column while the GAC only slightly contributed to its removal (for a passage of 100 L (1000 pore volumes)).     

A simple,straightforward correlative live‐cell‐imaging‐structured‐illumination‐microscopy approach for studying organelle dynamics

Most cellular organelles are highly dynamic and continuously undergo membrane fission and fusion to mediate their function. Documenting organelle dynamics under physiological conditions, therefore, requires high temporal resolution of the recording system. Concurrently, these structures are relatively small and determining their substructural organization is often impossible using conventional microscopy. Structured Illumination Microscopy (SIM) is a super resolution technique providing a two‐fold increase in resolution. Importantly, SIM is versatile because it allows the use of any fluorescent dye or protein and, hence, is highly applicable for cell biology. However, similar to other SR techniques, the applicability of SIM to high‐speed live cell imaging is limited. Here we present an easy, straightforward methodology for coupling of high‐speed live cell recordings, using spinning disk (SD) microscopy, with SIM. Using this simple methodology, we are able to track individual mitochondrial membrane fission and fusion events in real time and to determine the network connectivity and substructural organization of the membrane at high resolution. Applying this methodology to other cellular organelles such as, ER, golgi, and cilia will no doubt contribute to our understanding of membrane dynamics in cells. Microsc. Res. Tech. 78:777–783, 2015. © 2015 Wiley Periodicals, Inc.     

Indirect influence on modality on direct memory for words and their modality: Closed-head-injured and control participants.

Twenty closed-head-injured (CHI) patients and 28 control participants were tested on recall and recognition of words. In addition, memory for modality (i.e., visual vs. auditory) of word presentation was measured directly (i.e., recognition) and indirectly (i.e., by its influence on word and modality recognition). As predicted, the CHI patients were impaired relative to controls on all of the direct memory tasks; that is, word recall, word recognition, and modality judgment. However, the CHI and control groups did not differ significantly on the magnitude of the modality effect (i.e., facilitation due to correspondence of modality in learning and test). The findings are interpreted in the theoretical framework that distinguishes between item (i.e., words) and source (i.e., modality) memory and between direct and indirect measures of memory. (PsycINFO Database Record (c) 2010 APA, all rights reserved)