Miracle-dz/UniFAR-FTUs huggingface dataset:
The fractionation/concentration of aquatic humic substances by the sequential membrane system and their characterization with mass spectrometry

The sequential membrane system and electrospray ionization mass spectrometry are investigated on their usefulness for characterizing aquatic humic substances. In this research, the Suwannee River Fulvic Acid (SRFA) was used for the investigation. For the mass spectrometry, the optimum analytical conditions were determined. Two indices (i.e., the total ion intensity and the averaged molecular weight) obtained from the spectrum were found relevant for evaluating the physical characteristics of aquatic humic substances. The repetitious peaks at a discrete of 14 Da in the lower m/z range of the acquired spectrum suggested that the SRFA has the –CH2– based structure in its lower molecular weight region. For the sequential membrane system, the optimum operating conditions were determined. The SRFA could be fractionated and concentrated by this system. The significant difference of the averaged molecular weight among the concentrated fractions from the different size membranes indicated thatthis system is useful for the fractionation and concentration of the aquatic humic substances.
PYROLYSIS OF WASTE POLYSTYRENE IN HEAVY OIL

Abstract Waste plastics are an environmental problem because of recycling limitations and their resistance to natural decomposition. This research investigates the thermal degradation (pyrolysis) of waste polystyrene in heavy oil as a tertiary recycling method. Kinetic parameters for pyrolysis were obtained, and distillate products from the reaction were characterized by gas chromatography/mass spectroscopy. Four types of heavy oil were used to find which would be most suitable in this process. Complete pyrolysis of polystyrene occurred at temperatures lower than those reported in the literature.
A comparison of various commonly used correlation functions for describing total scattering

Total scattering, an increasingly important crystallographic research area, is defined theoretically in terms of correlation functions. Different researchers use different definitions for these functions, frequently leading to confusion in the literature. Here, a consistent set of equations for total-scattering correlation functions are developed and explicitly compared with other, often encountered, definitions. It is hoped that this will lead to increased transparency for newcomers to the field of total scattering.
Diffusion measurements by single-molecule spot-size analysis

We present a method to obtain diffusion coefficients from single-molecule images in video microscopy experiments. This method is based on the size of the single-molecule spot and delivers even for short trajectories a maximum number of data points and a higher statistical accuracy than does the common mean square displacement analysis. It is thus possible to obtain a diffusion coefficient from a single snapshot and to follow slow changes in single-molecule mobility in diffusion constant trajectories. Random walk simulations of single-molecule spots are used to validate the method.
Dynamic Force Spectroscopy and Biomolecular Recognition

Molecular recognition, also known as biorecognition, is the heart of all biological interactions. Originating from protein stretching experiments, dynamic force spectroscopy (DFS) allows for the extraction of detailed information on the unbinding process of biomolecular complexes. It is becoming progressively more important in biochemical studies and is finding wider applications in areas such as biophysics and polymer science. In six chapters, Dynamic Force Spectroscopy and Biomolecular Recognition covers the most recent ideas and advances in the field of DFS applied to biorecognition: Chapter 1: Reviews the basic and novel aspects of biorecognition and discusses the emerging capabilities of single-molecule techniques to disclose kinetic properties and molecular mechanisms usually hidden in bulk measurements Chapter 2: Describes the basic principle of atomic force microsocopy (AFM) and DFS, with particular attention to instrumental and theoretical aspects more strictly related to the study of biomolecules Chapter 3: Overviews the theoretical background in which experimental data taken in nonequilibrum measurements of biomolecular unbinding forces are extrapolated to equilibrium conditions Chapter 4: Reviews the most common and efficient strategies adopted in DFS experiments to immobilize the interacting biomolecules to the AFM tip and to the substrate Chapter 5: Presents and discusses the most representative aspects related to the analysis of DFS data and the challenges of integrating well-defined criteria to calibrate data in automatic routinary procedures Chapter 6: Overviews the most relevant DFS applications to study biorecognition processes, including the biotin/avidin pair, and selected results on various biological complexes, including antigen/antibody, proteins/DNA, and complexes involved in adhesion processes Chapter 7: Summarizes the main results obtained by DFS applied to study biorecognition processes with forthcoming theoretical and experimental advances Although DFS is a widespread, worldwide technique, no books focused on this subject have been available until now. Dynamic Force Spectroscopy and Biomolecular Recognition provides the state of the art of experimental data analysis and theoretical procedures, making it a useful tool for researchers applying DFS to study biorecognition processes.
Mechanisms of Astrocytic Calcium Wave Propagation and In Vitro Hippocampal Cell Death Are Determined By The Magnitude Of Mechanical Injury

It has been estimated that traumatic brain injury (TBI) costs the U.S. economy over $60 billion a year, with over 5.3 million people suffering some level of long term effects. Despite these figures, no effective pharmacological treatment has been successfully developed to help patients recover from TBI. A more complete understanding of both the immediate cellular reactions to injury and the longer-term responses may present new strategies for reducing damage and promoting repair. In this dissertation we first examine the ability for astrocytes to modulate the mechanisms of calcium wave propagation in response to increasing degrees of injury. As injury magnitude increases, the complexity of the calcium wave that is transmitted to surrounding uninjured regions also increases. At very mild levels of stretch calcium waves are primarily transmitted through extracellular ATP. As the level of stretch increases, gap junction communication and metabotropic glutamate receptor activation can be detected. The interaction between these three signaling pathways may transmit information about the severity of injury to surrounding astrocytes and may mediate immediate cellular responses. We also observe that the mechanical properties of cultured astrocytes are altered 24 hours after injury. Rapid stretch induces a decrease in the apparent Young’s modulus on nonnuclear regions of astrocytes, indicating that the cells are softer and more compliant. This change is associated with an upregulation of GFAP, which is a common marker for reactive gliosis. Finally, we investigate the interaction between glutamatergic and purinergic signaling in mediating cell death in hippocampal slices 24 hours following mechanical injury. Within the CA3 region of the hippocampus there is a significant increase in cell death after stretch-injury that can be attenuated by inhibiting the activity of the glutamatergic N-methyl D-aspartate (NMDA) receptors. Alternatively, blocking the activity of P2Y1 receptors is effective in limiting cell death. Our studies suggest that there is a high probability that P2Y1 receptor activity on astrocytes is responsible for inducing the over-excitation of extrasynaptic NMDA receptors, which is responsible for a major component of the observed cell death. Further studies into this pathway may lead to new approaches for pharmacological therapies after TBI. Degree Type Dissertation Degree Name Doctor of Philosophy (PhD) Graduate Group Bioengineering First Advisor David F. Meaney This dissertation is available at ScholarlyCommons: http://repository.upenn. edu/edissertations/172
Investigation of the Range of Carbon and Hydrogen Isotopes Within a Global Set of Gasolines

This study examined the range of carbon and hydrogen isotopes within a global set of gasolines to investigate the potential and limitations of isotopic analysis within environmental assessments of gasoline-contaminated sites. Bulk carbon and hydrogen isotope signatures within gasolines from the study had a range greater than 8‰ and 85‰, respectively. The combination of both isotopes produced a highly discriminating two-dimensional (2D) isotope fingerprint, highlighting the potential of 2D fingerprinting to differentiate gasoline sources. Compound-specific carbon isotope analysis was also completed to investigate its application as a method for risk-based management and environmental forensics.
Softening of wood polymers induced by moisture studied by dynamic FTIR spectroscopy

The softening of the wood polymers is very important in the utilization of wood fiber products. To better to understand how the hemicelluloses interact with the other wood polymers in the fiber ultrastructure and contribute to the mechanical properties of the wood, their softening inside the cell wall of pulp fibers was studied by dynamic FTIR spectroscopy under humid conditions. The two hemicelluloses of spruce, glucomannan and xylan, exhibited different softening behaviors indicating a different organization of the two hemicelluloses inside the cell wall. Lignin in mechanical pulp showed a more viscoelastic behavior already under dry conditions than the polysaccharides of the cell wall. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 94: 2032–2040, 2004
AMMONIUM ON POTASSIUM INTERACTION IN SWEET PEPPER

Nitrogen (N) metabolism in plants requires adequate potassium (K) content in the cytoplasm. However, the influence of NH4 + in the nutrient solution on plant uptake of K is controversial. To identify the effect of N form on K uptake in sweet pepper (Capsicum annum L. cv. Hazera 1195) two hydroponic experiments containing three K concentrations (0.5, 2.5, and 5.0 mM) combined with four NH4 + −N to NO3 − −N mM ratios (0:6, 0.9:5.1, 1.8:4.2, or 3:3) at a constant total of 6 mM N were conducted during the spring-summer and autumn-winter seasons. Early fruit yield was affected by K concentration but not by N form. Replacing 0.9–1.8 mM (15–30%) of NO3 − −N by NH4 + −N increased total fruit yield, especially when only 0.5 mM K was supplied. No significant interaction of NH4 + −N and K concentration on early and total fruit yield was found in either season. The uptake rate of NH4 + −N was related to its concentration and was independent of K concentration in the culture solution. The uptake rate of K was reduced as the NH4 + −N concentration increased above 1 mM. Compared to sole NO3 − −N supply, adding 0.9–1.8 mM NH4 + −N significantly increased the plant leaf phosphorus (P) and N content, but did not affect the leaf K content in the high yielding spring-summer season. It is concluded that 0.9–1.8 mM NH4 + −N (15–30% of total N) in the nutrient solution could increase both the total fruit yield and fertilizer K use efficiency in sweet pepper.
Anthocyanin-derived Pigments in Graciano, Tempranillo, and Cabernet Sauvignon Wines Produced in Spain

The anthocyanin profile of young wines made from Vitis vinifera cv. Graciano was determined by liquid chromatography/electrospray ionization-mass spectrometry (LC/ESI-MS) and compared with that of Vitis vinifera cv. Tempranillo and cv. Cabernet Sauvignon. Thirty-four anthocyanins and anthocyanin-derived pigments, including pyruvic acid, 4-vinylphenol, and vinylflavanol, plus direct and acetaldehyde-mediated condensation products, were found by direct analysis. Of particular interest was the presence of the cis isomer of malvidin-3-(699- p -coumaroylglucoside), reported here in wine for the first time. Anthocyanins in Graciano wines were characterized by a high level of peonidins and equal distribution between acetyl and cinnamoyl glucosides in comparison with Tempranillo and Cabernet Sauvignon wines. The occurrence of anthocyanin-derived pigments in the different wines appeared to be related to the concentration of the corresponding anthocyanin precursors.
Prolonged leaching of mineral forest soils with dilute HCl solutions: the solubility of Al and soil organic matter

Long‐term acidification has been shown to result in a considerable decrease in the amount of organically bound soil Al and in a gradual decrease in the solubility of Al. We examined the solubility of soil organic matter (SOM) and Al in four acid mineral soils (one Arenosol Ah, two Podzol Bh, and one Podzol Bs) as they were leached sequentially using a solution containing 0.001 m HCl and 0.01 m KCl. The acid leaching resulted in relative decreases in Al that were 2–6 times greater than for organic C. The organic C and Al dissolved by the acid leaching originated mainly in the pyrophosphate‐extractable fraction of the elements. Protonation seems to be a major mechanism in stabilizing the residual SOM, as indicated by small changes in effective cation exchange capacity with the degree of acid leaching. In the samples of Podzol Bh and Arenosol Ah soils the solubility of Al (defined as log10{Al3+} + 1.5pH) in equilibrium suspensions (0.01 m KCl) was closely related to the ratio of pyrophosphate‐extractable Al to pyrophosphate‐extractable organic C. The Podzol Bs sample probably contained a small amount of a surface‐reactive Al(OH)3 phase, which rapidly became depleted by the acid leaching.
Soil water drying and recharge rates as affected by tillage under continuous barley and barley-canola cropping systems in northwestern Canada

In areas of the northwestern Canadian Prairies, barley and canola are grown in a short growing season with high rainfall variability. Excessively dry soil in conventional tillage (CT) in dry periods and excessively wet soil in no-tillage (NT) in wet periods could cause a significant decrease in crop production by influencing the availability of soil water. The effects of CT, NT and NT with a 7.5-cm residue-free strip on the planting rows (NTR) on soil water drying (–dW/dt) and recharge (dW/dt) rates were studied in 1992 and 1993 during wet and dry periods to evaluate the impact of NTR, NT and CT systems on soil moisture condition. The soils, Donnelly silt loam and Donnelly sandy loam (both Gray Luvisol) were selected and soil water content by depth was measured by time domain reflectometry. Water retained at 6 matric potentials from –5 to –160 kPa were observed. In the field study, –dW/dt was significantly greater in CT than in NT in the silt loam for the 0- to 30-cm layer during the first 34 d after plan.
On the link between foam coarsening and surface rheology: why hydrophobins are so different

Why are hydrophobins so different? To understand this, here we compare the stability of foams made with hydrophobin HFBII, Quillaja saponin, β-lactoglobulin or β-casein. Our experimental design eliminates the effects of coalescence and creaming, allowing us to study Ostwald ripening primarily. We observe that in HFBII foams, disproportionation is effectively stopped and the air bubbles size remains practically constant over the time of the experiment. We explain this with the large differences in surface rheological properties of the adsorbed layers, which were studied using small and large deformation surface dilational and shear rheology experiments. At low surface coverage we have mapped the system behaviour to the equivalent 2D polymer network having similar dilational modulus vs. surface pressure dependence, allowing us to introduce an equivalent molecular “hardness”. This comparison indicates that even at low surface coverage, HFBII molecules behave as harder entity at the interface, when compared to other systems. We find similar behaviour at high surface coverage, where HFBII layers can form microscopic wrinkles at the interface. At large surface deformation the HFBII dilational modulus increases nearly monotonically, over a much larger range of surface pressures, and much higher moduli are reached compared to the other three systems. These observations correlate well with the observed difference in the foam behaviour.
Effects of AV-E digest and XFE liquid energy on nursery pig performance.

A total of 347 nursery pigs (PIC 1050, initially 11.0 lb) were used in a 44-d trial. Pens of pigs were balanced by initial BW and randomly allotted to 1 of 8 dietary treatments with 9 replications per treatment. Pigs were fed in 3 dietary phases (Phase 1, d 0 to 9; Phase 2, d 9 to 23; and Phase 3, d 23 to 44). The 8 dietary treatments included: (1) control diet containing no specialty protein sources; (2) 7.1% PEP2+ in Phase 1 and no specialty protein sources in Phase 2 or Phase 3; (3) 7.1% PEP2+ and 3.75% spray-dried animal plasma (SDAP) in Phase 1, 3.8% PEP2+ in Phase 2, and no specialty protein sources in Phase 3; (4) 7.1% PEP2+, 3.75% SDAP, and 3% liquid energy in Phase 1; 3.8% PEP2+ and 3% liquid energy in Phase 2; and 3% liquid energy but no specialty protein sources in Phase 3; (5) 7.1% PEP2+, 3.75% SDAP, and 3% choice white grease (CWG) in Phase 1; 3.8% PEP2+ and 3% CWG in Phase 2; and 3% CWG but no specialty protein sources in Phase 3; (6) 12.5% AV-E Digest (AV-E) and 2.5% spray-dried blood cells (SDBC) in Phase 1, 7.5% AV-E in Phase 2, and 2.5% AV-E in Phase 3; (7) 12.5% AV-E, 2.5% SDBC, and 3% liquid energy in Phase 1; 7.5% AV-E and 3% liquid energy in Phase 2; and 2.5% AV-E and 3% liquid energy in Phase 3; and (8) 12.5% AV-E, 2.5% SDBC, and 3% CWG in Phase 1; 7.5% AV-E and 3% CWG in Phase 2; and 2.5% AV-E and 3% CWG in Phase 3.
The Spatial Variation of Liquid Water and Droplet Concentration in Cumuli

Measurements of liquid water content and droplet concentration in cumuli over path lengths of about one metre have been used to investigate the structure of these clouds. The measurements indicate that the cloud process is far from adiabatic, and that a dominating role is played by the admixture of drier air from outside the cloud. They suggest, further, that the main source of this dry air may be the region above the cloud top. DOI: 10.1111/j.2153-3490.1958. tb02024.x
Semen quality of Curimba (Prochilodus lineatus) cryopreserved with vitamins

The present study examined the effect of adding the antioxidants vitamins C and E on the quality of semen cryopreserved of curimba ( Prochilodus lineatus ). Semen samples from nine breeding males were collected for analysis of rate (%) and duration (s) of sperm motility. The sperm pool was diluted into three cryoprotective solutions: Solution A: 5 gr. Beltsville Thawing Solution (BTS) added with 5 mL dimethyl sulfoxide (DMSO) and distilled water to 100 mL; Solution B: Solution A + 0.0001 mg vitamin E; Solution C: Solution A + 0.0001 mg vitamin C. The vitamins C and E were not toxic to the semen of curimba. The sperm motility did not present any significant difference. However, the semen cryopreserved with vitamin C had a longer duration of the motility after thawing. Therefore, the vitamin C is recommended for the cryopreservation of the semen of curimba.
Biodegradation of montmorillonite filled oxo‐biodegradable polyethylene

Oxo-biodegradation of polyethylene has been well studied with different pro-oxidants and it has been shown that pro-oxidants have limited role in the oxidation of polyethylene and do not have any role in microbial growth. However, in few recent studies, montmorillonite clay has been reported to promote the growth of microbes by keeping the pH of the environment at levels conducive to growth. In an attempt to improve the overall oxo-biodegradation of polyethylene, montmorillonite nanoclay has been used in this study along with a prooxidant. Film samples of oxo-biodegradable polyethylene (OPE) and oxo-biodegradable polyethylene nanocomposite (OPENac) were subjected to abiotic oxidation followed by microbial degradation using microorganism Pseudomonas aeruginosa. The progress of degradation was followed by monitoring the chemical changes of the samples using high-temperature gel permeation chromatography (GPC) and infrared spectroscopy (FTIR). The growth of bacteria on the surface of the polymer was monitored using environmental scanning electron microscopy. GPC data and FTIR results have shown that the abiotic oxidation of polyethylene is influenced significantly by the pro-oxidant but not by nanoclay. But, the changes in molecular weight distribution and FTIR spectra for the biodegraded samples indicate that the growth rate of P. aeruginosa on OPENac is significantly greater than that on OPE. It indicates that nanoclay, by providing a favourable environment, helps in the growth of the microorganism and its utilisation of the polymer surface and the bulk of the polymer volume.
Optimising viscosity and energy density of maize porridges for child weaning in developing countries

The energy density of traditional starch-based weaning foods used in many developing countries is a major constraint in ensuring adequate energy and nutrient intake for infants and young children. Viscosity and energy density of weaning foods are inextricably linked but studies investigating the two and their interrelationships are scarce. In this study, the factors influencing the viscosity and energy density of weaning maize porridges were investigated in a 28 fractional factorial experiment. The factors investigated included: flour particle size (coarse or fine), concentration (6 or 8%), cooking time (5 or 10 min), temperature at time of measurement (30 or 40°C), shear speed (256 or 512 rpm), shear time (20 or 60 min) and addition of energy-dense foods; groundnut paste replacing 25% of the maize flour (w/w) and/or pasteurised cow's milk replacing 10% of the water (v/v). The viscosity of the maize porridges was significantly increased by increased concentration and cooking time (P ≤ 0.0001) and use of f.
Produção vegetal e de óleo essencial de boldo pequeno em função de fontes de adubos orgânicos

A aplicacao de fertilizantes orgânicos, em plantas medicinais e aromaticas, normalmente modifica positivamente a producao vegetal e de oleo essencial. Neste contexto, tendo por fim avaliar a resposta de plantas de Plectranthus neochilus Schltr. , cultivadas com diferentes fontes de adubos orgânicos, o presente trabalho estudou a producao de biomassa, teor, rendimento e composicao quimica do oleo essencial. As mudas, apos a aclimatizacao, foram transplantadas para vasos de dez litros, acondicionados em casa de vegetacao. O experimento foi constituido por quatro tratamentos e quatro repeticoes (16 parcelas), sendo cada parcela composta por cinco vasos. Os tratamentos foram: ausencia de adubo orgânico (testemunha); aplicacao de 60 t ha-1 de esterco bovino; 30 t ha-1 de esterco avicola; 60 t ha-1 de composto orgânico. Aos 120 dias de cultivo, as plantas foram colhidas e uma parte das folhas frescas foi destinada a extracao do oleo essencial. O restante do material vegetal foi seco em estufa, ate atingir peso constante, para a determinacao da biomassa seca. As analises quimicas do oleo foram realizadas por cromatografia gasosa (CG-DIC e CG-EM). As fontes de adubo orgânico testadas promoveram diferencas entre os tratamentos em relacao a producao de biomassa, rendimento e composicao do oleo essencial de P. neochilus. A utilizacao de diferentes fertilizantes orgânicos nao modificou o teor de oleo volatil.