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Weed management in California water-seeded rice (Oryza sativa L.) is challenging due to herbicide-resistant weeds. Research on additional herbicide options is necessary to control herbicide-resistant weeds. Pendimethalin is a dinitroaniline herbicide commonly used in dry-seeded rice; however, it is not registered in water-seeded rice. This study was conducted to determine the pendimethalin fate in water-seeded rice after application at 1-, 3-, and 5-leaf stage rice. Ultra-high performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) was utilized to quantify pendimethalin and degradants in the water, soil and rice seedling tissue at 1, 5, and 14 days after treatment. Over 50% of recovered pendimethalin was observed in the rice tissue and over 25% in the soil and least observed in the water at all application timings and sampling dates. Three pendimethalin degradants were observed at low concentrations: p36 [1-(1-ethylpropyl)-5,6-dimethyl-7-nitro-1H-benximidazole], p44 [4-[(1-ethylpropyl) amino]-2-methyl-3,5-ditrobenzoic acid] and p48 [4,5-dimethyl-3-nitro-N2-(pentan-3-yl) benzene-1,2-diamine]. The degradant p36 was observed in all samples and most abundant in the soil. The degradants p36 and p44 increased in concentration in the water by 14 days after treatment. The degradants p44 and p48 were at low concentrations or below the lowest level of quantification in water, soil, and tissue samples. The pendimethalin parent molecule remained intact and was not readily metabolized in rice tissue. The crown region and shoots of the rice seedlings demonstrated greater pendimethalin concentrations compared to the roots at all rice stages; however, pendimethalin concentrations remained similar across the three sample timings. Rice root and shoot reduction was 16 and 13%, respectively, after the 1-leaf stage application averaged over sample timings, and 6 and 4% after the 5-leaf stage application. The results suggest the rice stage at the application timing is an important factor for pendimethalin tolerance; therefore, encouraging early root development can be beneficial for pendimethalin tolerance in water-seeded rice.
The classical theory of the interaction of light with the electron clouds of atoms and molecules will be discussed in this chapter. The discussion will begin with the interaction of a steady electric field with a collection of point charges, leading to the development of terms describing the electric dipole and quadrupole moments. The classical Lorentz model is then introduced to describe interaction of an oscillating electric field with the electron cloud of an atom, and the concepts of absorption and emission are introduced. The propagation of a light wave through a medium with electric dipoles is then discussed. Finally, the classical theory of radiation from an oscillating dipole is discussed.
Laser absorption spectroscopy is widely used for sensitive and quantitative detection of trace species. In this chapter, the density-matrix approach is used to introduce laser absorption spectroscopy. Spectroscopic quantities that characterize the absorption process are defined, and the relationships among these quantities are discussed. Broadening processes for spectral line shapes are also discussed, and the Doppler, Voigt, and Galatry profiles are introduced. The chapter concludes with a detailed example calculation featuring NO absorption.
For the engineer or scientist using spectroscopic laser diagnostics to investigate gas-phase media or plasmas, this book is an excellent resource for gaining a deeper understanding of the physics of radiative transitions. While a background in quantum mechanics is beneficial, the book presents a comprehensive review of the relevant aspects, extensively covering atomic and molecular structure alongside radiative transitions. The author employs effective Hamiltonians and Hund's case (a) basis wavefunctions to develop the energy level structure of diatomic molecules. These techniques also form the basis for treating radiative transitions in diatomic molecules. Recent advancements in quantum chemistry, enabling readers to calculate absolute single-photon and Raman transition strengths, are also presented. Illustrated with detailed example calculations of molecular structure and transition rates, this self-contained reference for spectroscopic data analysis will appeal to professionals in mechanical, aerospace, and chemical engineering, and in applied physics and chemistry.
This study intends to provide a comprehensive review of the basic concepts, types, applications, and experimental studies of frequency selective rasorber (FSR) presented in the literature. Analyzing the characteristics of FSR became crucial for future adaptability when taking into consideration of immense development in RADAR, military, stealth, and electromagnetic interference applications. The rasorber was initially conceived as a radome for antennas and it was developed expeditiously in recent years. This survey is focused on evaluating the unit cell design (2D, 2.5D, and 3D), equivalent circuit model, polarization characteristics, fractional bandwidth, insertion loss, absorptivity, bandwidth enhancement for absorption, transmission, and their applications based on the FSR. Various techniques like exploiting lumped elements, magnetic materials, lumped components, dual/triple layer structures, varactor diodes, PIN diodes, and distributed elements (slots and stubs) are used to improve the novelty and performance of the FSR that are discussed in the works of literature. At last, these techniques, bandwidth, structures, and performances are compared based on their relative positions to feature the benefits and limitations.
Microplastic pollution has become a global environmental challenge, with significant impacts on ecosystems and human health. Microbes have emerged as a promising tool in the combating against microplastic contamination. However, the complex relationship between microbes and microplastics presents both opportunities and challenges, leading to a nuanced understanding of their applications in degradation. This paper provides critical insights into the multifaceted roles of different microorganisms in microplastic degradation. It begins by highlighting the ‘good’ aspects, where several strains of microorganisms show the potential to break down microplastics through enzymatic activities and the formation of biofilms. Conversely, the ‘bad’ aspects of microbial involvement in microplastic degradation are examined. Microorganisms can facilitate the transport and bioaccumulation of microplastics in various ecosystems, potentially exacerbating their harmful effects. The ‘ugly’ side of microplastic degradation includes the production of harmful byproducts during microbial breakdown, raising concerns about secondary pollution and toxicity. The concept of plastisphere is discussed in this context, focusing on the phototrophs, photoheterotrophs and heterotrophs. Novel technologies involving microbial degradation of microplastics are also explained. The work emphasises the need for a comprehensive and balanced approach regarding the application of microorganisms in microplastic degradation and remediation.
The frequency, v, for O-D stretching in D2O films between the superimposed layers of different micas and montmorillonites was measured at several film thicknesses and temperatures of 2° and 25°C by infrared spectroscopy. The molar absorptivity, ε, for O-D stretching in HDO films between the montmorillonite layers was also measured at different film thicknesses and 25°C. It was found that v is related to mw/mm, the mass ratio of D2O to mica or montmorillonite, by the equation v = v0 exp β/(mwmm where v0 is the O-D stretching frequency in pure D2O and ß is a constant. Since mw/mm is proportional to a, the area under the absorption peak, mw/mm can be replaced by a in this equation. It was also found that ε decreased dramatically as the thickness of the water film between the montmorillonite layers decreased. These results were interpreted to mean that the structure of the interlayer water is perturbed by the interlayer cations and/or silicate surfaces.
Eurasian watermilfoil (Myriophyllum spicatum L.) is an invasive aquatic plant that can hybridize with the native northern watermilfoil (M. sibiricum Kom.). These milfoil hybrids (M. spicatum × M. sibiricum) are becoming more prevalent in many lakes where the invasive and the native milfoil co-occur. Hybrid plants are more vigorous than either parent with a faster growth rate and lower sensitivity to some herbicides. The aquatic herbicides endothall and 2,4-D provide two effective modes of action for management of the hybrids. For more than a decade, these two herbicides have been used in combination as an effective control option and a resistance management strategy. How this combination impacts herbicide movement and efficacy is unknown. Therefore, the objective of this research was to determine the activity of endothall and 2,4-D combined compared with activity applied alone. Absorption and translocation of endothall, 2,4-D, and the combination was determined in hybrid plants over a 96-h time course. Endothall accumulation was not impacted when these herbicides were applied in combination; however, 2,4-D accumulation increased by 80%, relative to when 2,4-D was applied alone. Endothall translocation from shoots to roots decreased by almost 50% when applied in combination with 2,4-D (alone = 16.7% ± 2.6%; combination = 9.2% ± 1.2%). Shoot-to-root translocation of 2,4-D also decreased when the two herbicides were applied in combination (24.8% ± 2.6% when applied alone to only 3.93% ± 0.4% when in the presence of endothall). This research demonstrates that combining herbicides can significantly impact herbicide activity in plants. Future research is needed to determine whether this reduced translocation negatively impacts operational effectiveness when these herbicides are applied in combination.
Virtually all of the energy at the surface of the Earth comes to us from the Sun. This is the energy that, in combination with the greenhouse gases in the atmosphere, maintains our current surface temperature in the range where liquid water is present. In this chapter we will examine solar radiant energy, and its most important interactions with the various constituents of the Earth’s atmosphere. Most of it reaches the lower troposphere, some to be absorbed by water vapour, and some to be scattered by clouds, molecules, or aerosols. The rest (roughly half) reaches the ground. Human activity has the power to alter these inflows, in a number of ways. We devote one section to the potentially disastrous Nuclear Winter scenario, and another to the potentially useful idea, known as Geoengineering, of reflecting some of the incoming sunlight in order to re-balance the Earth’s energy budget.
The reduction of hexavalent chromium species in aqueous solutions by interaction with Fe(II)-bearing solid surfaces was studied using a 0.96 × l0−3 M Cr(VI) solution and iron-rich clays with different Fe(II)/Fe(III) ratios, layer charge, and exchange properties, i.e., chlorite, corrensite, and montmorillonite. Experimental studies demonstrated that Fe(II)-bearing phyllosilicates reduce aqueous Cr(VI) ions at acidic pH. Chlorite and corrensite, owing to the high Fe(II)/Fe(III) ratio, are electrochemically reactive, as rapid Cr(VI) reduction indicated. In contrast, montmorillonite showed minimum to nil reactivity towards Cr(VI). Furthermore, corrensite, which is high in both Fe(II)/Fe(III) ratio and exchange capacity, adsorbs the greatest amount of chromium.
X-ray absorption spectroscopy at Al, Mg, Fe, and Cr K-edges was used to investigate the adsorbed chromium species. The montmorillonite sample, unaffected by treatment with Cr(VI) solution, displays no change at any investigated edge. Edge shape and energy also do not change for the Mg and Al spectra in corrensite, and changes are minor in chlorite. By contrast, the Fe K-edge changes both in chlorite and corrensite, and indicates an increase of Fe(III) in treated samples at the expense of pre-existing Fe(II). Cr K-edge spectra show that chlorite and corrensite sorb Cr(III), which implies its reduction from Cr(VI) in the interacting solution.
This chapter examines two related heads of power: the immigration power in section 51(xxvii) and the aliens power in section 51(xix) of the Australian Constitution. Immigration is concerned with the act of a non-Australian entering into Australia and the process of an immigrant becoming absorbed into the Australian community so that they are no longer an immigrant. Whether a person is an immigrant is largely a question of fact. By contrast, alienage is a legal status. Within the limits of the concept of ‘alien’, Parliament has power to determine who is and is not an alien. The contemporary position is that an alien is anyone who is a non-citizen. The aliens power includes the power to take away citizenship so as to turn a citizen into an alien. The case law shows that all immigrants are aliens but that not all aliens are immigrants. Both heads of power can be used to regulate the conduct of individuals, including providing for their deportation. Because the meaning of the concepts involved is clearer, Parliament nowadays tends to rely on the aliens power to support legislation dealing with migration and related policy areas.
Clay minerals, such as layered double hydroxide (LDH) and montmorillonite (MMT), have attracted a great deal of attention for biological applications. Along with the rapid development of nanotechnology, public concern about the potential toxicity of nanoparticles is growing. In the present work, cytotoxicity of LDH and MMT was assessed in terms of inhibition of cell proliferation, generation of oxidative stress, and induction of inflammation response. Moreover, the biokinetics of LDH and MMT were evaluated; biokinetics provides information about in vivo absorption, distribution, and excretion kinetics. The results demonstrated that both LDH and MMT inhibited cell proliferation at relatively large concentrations and after long exposure time compared to other inorganic nanoparticles, although they generated reactive oxygen species (ROS). LDH induced pro-inflammatory cytokines in a size-dependent manner. Biokinetic study revealed that, after single-dose oral administration to mice, both LDH and MMT had extremely slow oral rates of absorption and did not accumulate in any specific organ. All the results suggest great potential of clay minerals for biological application at safe levels.
Psilocybin Therapy (PT) is being increasingly studied as a psychiatric intervention. Personality relates to mental health and can be used to probe the nature of PT's therapeutic action.
Methods
In a phase 2, double-blind, randomized, active comparator controlled trial involving patients with moderate-to-severe major depressive disorder, we compared psilocybin with escitalopram, over a core 6-week trial period. Five-Factor model personality domains, Big Five Aspect Scale Openness aspects, Absorption, and Impulsivity were measured at Baseline, Week 6, and Month 6 follow-up.
Results
PT was associated with decreases in neuroticism (B = −0.63), introversion (B = −0.38), disagreeableness (B = −0.47), impulsivity (B = −0.40), and increases in absorption (B = 0.32), conscientiousness (B = 0.30), and openness (B = 0.23) at week 6, with neuroticism (B = −0.47) and disagreeableness (B = −0.41) remaining decreased at month 6. Escitalopram Treatment (ET) was associated with decreases in neuroticism (B = −0.38), disagreeableness (B = −0.26), impulsivity (B = −0.35), and increases in openness (B = 0.28) at week 6, with neuroticism (B = −0.46) remaining decreased at month 6. No significant between-condition differences were observed.
Conclusions
Personality changes across both conditions were in a direction consistent with improved mental health. With the possible exception of trait absorption, there were no compelling between-condition differences warranting conclusions regarding a selective action of PT (v. ET) on personality; however, post-ET changes in personality were significantly moderated by pre-trial positive expectancy for escitalopram, whereas expectancy did not moderate response to PT.
Menaquinone-7 (MK-7), a multipotent vitamin K2, possesses a wide range of biological activities, a precise curative effect and excellent safety. A simple and rapid LC-APCI-MS/MS method for the determination of MK-7 in human plasma with single liquid–liquid extraction (LLE) extraction and 4·5-min analysis time has been developed and validated. Four per cent bovine serum albumin (BSA) was used as surrogate matrix for standard curves and endogenous baseline subtraction. This method was reproducible and reliable and was used to analyse of MK-7 in human plasma. The endogenous circadian rhythm and bioavailability of MK-7 were investigated in two randomised single-dose, open, one-way clinical trials (Study I and Study II). A total of five healthy male subjects were enrolled in Study I and 12 healthy male subjects in Study II. Single-dose (1 mg) of MK-7 was given to each subject under fasting condition, and all eligible subjects were given a restricting VK2 diet for 4 d prior to drug administration and during the trial. The experiment results of Study I demonstrated that endogenous MK-7 has no circadian rhythm in individuals. Both studies showed MK-7 are absorbed with peak plasma concentrations at about 6 h after intake and has a very long half-life time.
We consider a one-dimensional superprocess with a supercritical local branching mechanism $\psi$, where particles move as a Brownian motion with drift $-\rho$ and are killed when they reach the origin. It is known that the process survives with positive probability if and only if $\rho<\sqrt{2\alpha}$, where $\alpha=-\psi'(0)$. When $\rho<\sqrt{2 \alpha}$, Kyprianou et al. [18] proved that $\lim_{t\to \infty}R_t/t =\sqrt{2\alpha}-\rho$ almost surely on the survival set, where $R_t$ is the rightmost position of the support at time t. Motivated by this work, we investigate its large deviation, in other words, the convergence rate of $\mathbb{P}_{\delta_x} (R_t >\gamma t+\theta)$ as $t \to \infty$, where $\gamma >\sqrt{2 \alpha} -\rho$, $\theta \ge 0$. As a by-product, a related Yaglom-type conditional limit theorem is obtained. Analogous results for branching Brownian motion can be found in Harris et al. [13].
An overview of optical scattering in the atmosphere includes the sizes and concentration of scatterers, the mathematical formalism of scattering, and definitions of the lidar scattering and extinction coefficients. The Rayleigh, Mie, and geometric scattering regimes are defined by the scattering parameter, and implications of Rayleigh scattering on lidar measurements are elucidated for both signals and background. Molecules store energy in translational, rotational, and vibrational motions, and atoms store energy in electronic excitations. These energy storage mechanisms cause the lidar observables of Doppler shifts, molecular and Raman spectra, and atomic spectra, which, along with Rayleigh scattering, enable lidar measurements of temperatures and winds; water vapor and trace gas concentrations; and aerosol extinction coefficients at altitudes from the surface up to the mesosphere and lower thermosphere. The lidar techniques that exploit all these phenomena operate over a range of wavelengths from the long wave infrared to the ultraviolet and the reasons for the differing wavelengths of the various techniques are explained with a graphic that summarizes the chapter.
The rates of dietary protein digestion and absorption can be significantly increased or decreased by food processing treatments such as heating, gelling and enzymatic hydrolysis, with subsequent metabolic impacts, e.g. on muscle synthesis and glucose homeostasis.
This review examines in vivo evidence that industrial and domestic food processing modify the kinetics of amino acid release and absorption following a protein-rich meal. It focuses on studies that used compositionally-matched test meals processed in different ways.
Food processing at extremely high temperature at alkaline pH and/or in the presence of reducing sugars can modify amino acid sidechains, leading to loss of bioavailability. Some protein-rich food ingredients are deliberately aggregated, gelled or hydrolysed during manufacture. Hydrolysis accelerates protein digestion/absorption and increases splanchnic utilisation. Aggregation and gelation may slow or accelerate proteolysis in the gut, depending on the aggregate/gel microstructure.
Milk, beef and eggs are heat processed prior to consumption to eliminate pathogens and improve palatability. The temperature and time of heating affect protein digestion and absorption rates, and effects are sometimes non-linear. In light of a dietary transition away from animal proteins, more research is needed on how food processing affects digestion and absorption of non-animal proteins.
Food processing modifies the microstructure of protein-rich foods, and thereby alters protein digestion and absorption kinetics in the stomach and small intestine. Exploiting this principle to optimise metabolic outcomes requires more human clinical trials in which amino acid absorption rates are measured and food microstructure is explicitly considered, measured and manipulated.
Hydrilla [Hydrilla verticillata (L. f.) Royle] is often called the “perfect aquatic weed,” as it has numerous physiological adaptations that make it highly aggressive and competitive. Hydrilla verticillata has historically been managed effectively using fluridone; however, the overreliance on this single mechanism of action (MOA) resulted in evolved fluridone resistance in the late 1990s. Where fluridone-resistant H. verticillata populations evolved, endothall became widely used for H. verticillata control. In 2018, florpyrauxifen-benzyl, a highly active auxin-mimic herbicide, was registered for H. verticillata control, and its use has increased since its introduction. Endothall and florpyrauxifen-benzyl provide two effective MOAs for H. verticillata management, and combining these two MOAs would be an effective strategy to delay further resistance evolution. The objective of this research was to determine whether combining endothall and florpyrauxifen-benzyl would significantly impact the behavior of either herbicide in dioecious (DHV) or monoecious (MHV) H. verticillata compared with their behavior when applied alone. Endothall and florpyrauxifen-benzyl absorption and accumulation alone and in combination were measured over a 192-h time course. Translocation patterns were also determined. Herbicide accumulation in MHV and DHV was not impacted when these herbicides were applied in combination. Endothall translocation from shoots to roots in DHV was not impacted (alone = 18.7 ± 1.4%; combination = 23.2 ± 2.2%); however, endothall shoot-to-root translocation in MHV was reduced from 16.2 ± 1.3% applied alone to 2.2 ± 0.1% when applied in combination with florpyrauxifen-benzyl. Florpyrauxifen-benzyl shoot-to-root translocation was reduced in both MHV and DHV when applied in combination with endothall. Florpyrauxifen-benzyl translocation was reduced by 16- and 6-fold in DHV and MHV, respectively. These data do not suggest that there would be operational impacts from endothall and florpyrauxifen-benzyl mixtures. Still, there appear to be changes in herbicide behavior, primarily shoot-to-root translocation, when these two herbicides are applied in combination.
In those moments, or seconds, or hours, when focus on our creative work overrides input from the outside world, we are in the altered state of a creative trance. Shaped by individual experiences, social circumstances, and cultural traditions, the creative trance is multifaceted and psychologically significant. Taking numerous forms throughout the sciences, arts, sports, and self-transformation, it can change the world. At age sixteen, Albert Einstein’s visualization of riding on a light beam became a basis for his theory of special relativity. It can also be the inner deliberations of both Mozart and Shostakovich, who composed finished music in their minds. Cross-culturally, meditation and sleep are central to a creative trance. The Native North American Chippewa weave dream images into their beadwork and banners. In addition to the trance of creation, there is an audience creative trance of reception that ranges from pleasant enjoyment to the overwhelming response of the Stendhal syndrome.
Children's imagination was traditionally seen as a wayward, desire-driven faculty that is eventually constrained by rationality. A more recent, Romantic view claims that young children's fertile imagination is increasingly dulled by schooling. Contrary to both perspectives, this Element argues that, paradoxically, children's imagination draws much inspiration from reality. Hence, when they engage in pretend play, envision the future, or conjure up counterfactual possibilities, children rarely generate fantastical possibilities. Their reality-guided imagination enables children to plan ahead and to engage in informative thought experiments. Nevertheless, when adults present children with less reality-based possibilities – via biblical narratives or the endorsement of special beings – children are receptive. Indeed, such imaginary possibilities can infuse their otherwise commonsensical appraisal of reality. Finally, like adults, young children enjoy being absorbed into a make-believe, fictional world but faced with real-world problems calling for creativity, they often need guidance, given their limited knowledge of prior solutions.