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The decomposition of deadwood plays a very important role in the functioning of the forest ecosystem. The present study was conducted with the objectives to: (1) determine the amount of deadwood respiration depending on species and degree of decomposition; (2) determine the extent of the impact of decomposing wood on the amount of respiration in surrounding soil; (3) find a relationship between the amount of respiration and the chemical fractional composition of soil organic matter. Our research has shown that respiration of decaying wood samples was 2-3 times lower compared to soil, regardless of the type of wood and the degree of wood decomposition. The conducted analyses confirmed the influence of the species of wood and the degree of decomposition on the respiration rate in wood samples. More decomposed wood (4th and 5th degree of decomposition) releases more CO2 compared to less decomposed wood and the highest CO2 emissions were recorded for aspen and alder wood. Better understanding of the mechanisms and factors affecting CO2 emissions in forest ecosystem can help reduce climate change. [ABSTRACT FROM AUTHOR]

This paper is concerned with time decay rates of the strong solutions of an incompressible the coupled modified Navier-Stokes and Maxwell equations in a half space $ \mathbb{R}^3_+ $. With the use of the spectral decomposition of the Stokes operator and $ L^p-L^q $ estimates developed by Borchers and Miyakawa [2], we study the $ L^2 $-decay rate of strong solutions.

Abstract Environmental DNA (eDNA) analysis methods have been developed to detect organism distribution and abundance/biomass in various environments. eDNA degradation is critical for eDNA evaluation. However, the dynamics and mechanisms of eDNA degradation are largely unknown, especially when considering different eDNA sources, for example, cells and fragmental DNA. We experimentally evaluated the degradation rates of eDNA derived from multiple sources, including fragmental DNA (internal PCR control [IPC]), free cells (from Oncorhynchus kisutch), and resident species. We conducted the experiment with pond and seawater to evaluate the differences between freshwater and marine habitats. We quantified the eDNA copies of free cells, fragmental DNA, and resident species (Cyprinus carpio in the pond and Trachurus japonicus in the sea). We found that eDNA derived from both cells and fragmental DNA decreased exponentially in both the sea and pond samples. The degradation of eDNA from resident species showed similar behavior to the cell‐derived eDNA. We evaluated three degradation models with different assumptions and degradation steps and found that a simple exponential model was effective in most cases. Our findings on cell‐ and fragmental DNA‐derived eDNA provide fundamental information about the eDNA degradation process and can be applied to quantify eDNA behavior in natural environments.

In a Hilbert space, we consider a class of nonlinear fractional equations having the Caputo fractional derivative of the time variable t and the space fractional function of the self-adjoint positive unbounded operator. We consider various cases of global Lipschitz and local Lipschitz source with time-singular coefficient. These sources are generalized of the well–known fractional equations such as the fractional Cahn–Allen equation, the fractional Burger equation, the fractional Cahn–Hilliard equation, the fractional Kuramoto–Sivashinsky equation, etc. Under suitable assumptions, we investigate the existence, uniqueness of maximal solution, and stability of solution of the problems with respect to perturbed fractional orders. We also establish some global existence and prove that the global solution can be approximated by known asymptotic functions as t → ∞ . [ABSTRACT FROM AUTHOR]

A wave equation in a bounded and smooth domain of ℝ n with a delay term in the nonlinear boundary feedback is considered. Under suitable assumptions, global existence and uniform decay rates for the solutions are established. The proof of existence of solutions relies on a construction of suitable approximating problems for which the existence of the unique solution will be established using nonlinear semigroup theory and then passage to the limit gives the existence of solutions to the original problem. The uniform decay rates for the solutions are obtained by proving certain integral inequalities for the energy function and by establishing a comparison theorem which relates the asymptotic behavior of the energy and of the solutions to an appropriate dissipative ordinary differential equation. [ABSTRACT FROM AUTHOR]

We designed two mutants of photoprotein Mnemiopsin 2 (Mn2) including M52I and V144I, where the mutations were applied in the EF-hand loops I and III. Far-UV CD measurements demonstrated that the stability of the helices in the wild-type (WT) protein is greater compared with the mutants. Heat-induced denaturation experiments in the apo-form of photoproteins showed that WT Mn2 has higher value of the enthalpy change for the unfolding process, indicating that it has more stabilizing interaction compared with mutants. According to the activity measurement data, both mutants, particularly V144I have lower initial intensity as well as slower decay rate as compared with the WT photoprotein. Importantly, it was found that V144I variant shows 25 nm of red shift in the characteristic wavelengths as compared with the WT photoprotein. This finding can be considered as an advantage for in vivo application of photoprotein for imaging purposes. It concluded that this position on loop III of Mn2 is a hotspot point for characteristic wavelength determination. However, further research on this mutant is needed for making stable variants of Mn2 with novel optical features. [ABSTRACT FROM AUTHOR]

We consider the full compressible Navier-Stokes equations with reaction diffusion. A global existence and uniqueness result of the strong solution is established for the Cauchy problem when the initial data is in a neighborhood of a trivially stationary solution. The appearance of the difference between energy gained and energy lost due to the reaction is a new feature for the flow and brings new difficulties. To handle these, we construct a new linearized system in terms of a combination of the solutions. Moreover, some optimal time-decay estimates of the solutions are derived when the initial perturbation is additionally bounded in L1. It is worth noticing that there is no decay loss for the highest-order spatial derivatives of the solution so that the long time behavior for the hyperbolic-parabolic system is exactly the same as that for the heat equation. As a byproduct, the above time-decay estimate at the highest order is also valid for compressible Navier-Stokes equations. The proof is accomplished by virtue of Fourier theory and a new observation for cancellation of a low-medium-frequency quantity. [ABSTRACT FROM AUTHOR]

Photodegradation is a key process impacting the lifetime of oxalate in the atmosphere, but few studies investigated this process in the field due to the complex mixing and sources of oxalate. Oxalate-containing particles were measured via single-particle aerosol mass spectrometry at coastal and suburban sites in Qingdao, a coastal city in North China in the summer of 2016. The mixing state and influence of different ambient conditions on the source and photodegradation of oxalate were investigated. Generally, 6.3% and 12.3% of the total particles (by number) contained oxalate at coastal and suburban sites, respectively. Twelve major types of oxalate-containing particles were identified, and they were classified into three groups. Biomass burning (BB)-related oxalate–K and oxalate–carbonaceous particles were the dominant groups, respectively, accounting for 68.9% and 13.6% at the coastal site and 72.0% and 16.8% at the suburban site. Oxalate–Heavy metals (HM)-related particles represented 14.6% and 9.3% of the oxalate particles at coastal and suburban sites, respectively, which were mainly from industrial emissions (Cu-rich, Fe-rich, Pb-rich), BB (Zn-rich), and residual fuel oil combustion (V-rich). The peak area of oxalate at the coastal site decreased immediately after sunrise, while it increased during the daytime at the suburban site. However, the oxalate peak area of Fe-rich particles at both sites decreased after sunrise, indicating that iron plays an important role in oxalate degradation in both environments. The decay rates (k) of Fe-rich and BB-Fe particles at the coastal site (−0.978 and −0.859 h−1, respectively), were greater than those at the suburban site (−0.512 and −0.178 h−1, respectively), owing to the high-water content of particles and fewer oxalate precursors. The estimated k values of oxalate peak area for different ambient conditions were in the same order of magnitude, which can help establish or validate the future atmospheric models. [ABSTRACT FROM AUTHOR]

In this paper, we consider a viscoelastic Bresse-type system subjects to nonlinear damping, nonlinear time delay term, a finite memory and with homogeneous Dirichlet-Neumann-Neumann boundary conditions. Under a condition between the weight of delay term in the feedback and the weight of the term without delay, we prove, in case of equal speeds of wave propagation, new decay results that generalise and improve the recent results in the literature. [ABSTRACT FROM AUTHOR]

Aims: Changes caused by single herbivore species grazing to soil and plant interfaces can significantly affect the leaf litter decomposition rates within ecosystems. However, we intended to study how grazing by multiple herbivore species regulate the litter decomposition process and associated soil or plant properties in Leymus chinensis dominant meadow steppe. Methods: Two consecutive randomized field experiments were conducted between May 2017 and May 2019: 1) a grazing experiment with four (control or no, sheep, cattle, and mixed (sheep + cattle)) grazing treatments to explore the effects of moderate grazing on soil properties and L. chinensis litter quality and 2) the litter decomposition experiment to evaluate the decay rate in grazed or non-grazed litter by using litter bag technique. Results: Litter decay rate was the highest in mixed grazed litter as compared to litter grazed by individual herbivore species. Both herbivore grazing and incubation time affected decay rate of L. chinensis litter by modifying soil moisture and nitrogen (N) content, as well as, litter N and lignin contents. Plant litter quality has been displayed to be a dominant regulator of litter decay rate than soil physical or chemical properties in mixed grazed litter. Conclusions: Livestock diversification benefited litter decomposition indirectly by modifying plant litter quality with time. Therefore, herbivore assemblages should be given more importance in future research on litter decomposition process to mediate nutrient cycling in grassland. [ABSTRACT FROM AUTHOR]

A system of three semilinear wave equations with strong external forces in $ \mathbb{R}^n $ is considered. We use weighted phase spaces, where the problem is well defined, to compensate the lack of Poincare's inequality. Using the Faedo-Galerkin method and some energy estimates, we prove the existence of global solution. By imposing a new appropriate conditions, which are not used in the literature, with the help of some special estimates and generalized Poincaré's inequality, we obtain an unusual decay rate for the energy function. It is a generalization of similar results in [16,29,31]. The work is relevant in the sense that the problem is more complex than what can be found in the literature.

The boundary stabilization problem of the Boussinesq KdV–KdV type system is investigated in this paper. An appropriate boundary feedback law consisting of a linear combination of a damping mechanism and a delay term is designed. Then, considering time-varying delay feedback together with a smallness restriction on the length of the spatial domain and the initial data, we show that the problem under consideration is well-posed. The proof combines Kato's approach and the fixed-point argument. Last but not least, we prove that the energy of the linearized KdV–KdV system decays exponentially by employing the Lyapunov method. [ABSTRACT FROM AUTHOR]

This brief considers the generalized exponential stability of impulsive stochastic functional differential equations (ISFDEs). Initially, An extension of Halanay inequality is derived. Subsequently, by employing this generalized Halanay inequality, we establish the generalized exponential stability result for the given systems. [ABSTRACT FROM AUTHOR]

Litterfall, directly and indirectly, affects the soil physicochemical properties, microbial activity, and diversity of soil fauna and flora by adding organic matter and nutrients to the soil. This study explores litterfall dynamics such as litterfall production, litter decomposition rate, and associated nutrient return in three forest types, that is, camphor tree forest (CTF), Masson pine forest (MPF), and camphor tree and Masson pine mixed forest (CMF), in subtropical China. Results showed that CMF had the highest mean annual litterfall production (4.30 ± 0.22 t ha−1), which was significantly higher than that of MPF (3.41 ± 0.25 t ha−1) and CTF (3.26 ± 0.17 t ha−1). Leaf represented the major fraction of litterfall, constituting over 71% of the total litterfall mass in the three forest types. The contribution of branch litter was 16.3, 8.9, and 16.9%, and miscellaneous litter was 12.6, 18.9, and 11.1% in CTF, MPF, and CMF, respectively. The concentration of macronutrients ranked as N > Ca > K > Mg > P in all litter fractions. The total annual macronutrient return to the soil from the litterfall was in order as CTF (74.2 kg ha−1‧yr−1) > CMF (70.7 kg ha−1‧yr−1) > MPF (33.6 kg ha−1‧yr−1). The decomposition rate was higher in leaf litter than in branch litter throughout the three forests. Among the forest types, the leaf and branch decomposition rates were in a pattern: CTF > CMF > MPF. The ratio of C/N in both leaf and branch litters was significantly higher in MPF than in CTF and CMF, while no significant differences in N/P ratio were found in these litters among the three forests. The high N:P ratios in leaf litter (23/30) and the branch (24/32) litter indicated the high N returning and low nutrient returning to the soil. Our results suggested that the broadleaved forests have faster litter decomposition and higher macronutrient returns than conifer forests. Moreover, the litter decomposition rate was mainly associated with litterfall quality and chemical composition. The introduction of broadleaved trees into monoculture coniferous stands could increase litter production nutrients return, and thus, it had advantages in soil nutrients restoration and sustainable forest management.

Abstract In vertebrate population estimation, converting faecal density into animal density requires information on the faecal production rate, decay rate and faecal density. Differences in the above factors for long‐lived species across age classes were not evaluated. We have evaluated these factors associated with the dung count of Asian elephants (Elephas maximus) in the tropical forest of southern India. The defecation rate of elephants was determined in semi‐wild elephants at the Mudumalai elephant camp. The relationship between dung bolus diameter and age was determined to estimate the age of the elephant. The total and age‐specific elephant density based on dung bolus diameter was estimated. A total of 24 transect lines of 2–4 km (125 km) were sampled in the study area. An experiment was conducted to assess the detection probability across the age classes of dung piles. The dung decay rates across age classes and seasons were determined by marking fresh dung piles (n = 1551). The dung‐based age structure assessment and its limitations were evaluated. The mean defecation rate was 13.51 ± 0.51 per day. The defecation rate was significantly lower for the younger age class and increased with the age of elephants. Defecation rates were significantly lower in the wet season than in the dry. The dung bolus diameter positively increased with the age of elephants, and the growth curve can be used to predict the age and age structure of elephant populations. The disparity in the dung production rate results in the lower availability of younger age class (juvenile and calf) dung in the transect for counting, which results in lower dung abundance. The detection probability of dung piles of younger age classes was low (0.58). The survival rates of dung piles of younger age classes were lower and increased with the age of elephants in the wet season. Hence, the demographic assessment of the population based on dung needs to consider age‐specific differences in dung production, decay and detection probability. Although the demographic assessment using dung provides insight into population age structure, it has limitations in predicting age structure for young elephants.

Winged beans accumulate abundant field heat following harvest, and their shelf life is shortened if precooling is not performed promptly. In the present study, top-suction forced-air precooling (FC) was employed to rapidly remove field heat from pods, and its effects on winged bean pod storage quality and shelf life were assessed. After postharvest FC to remove field heat from winged bean pods, the mean 1/2 precooling time was 5.8 min and 7/8 precooling time was 14.7 min, which was 9.6 times and 11.7 times faster than room cooling (RC), respectively. Moreover, after FC was applied to remove field heat, the weight loss rate at 7/8 precooling time was 0.92%, significantly lower than that after RC was applied (1.98%). FC could delay decay, and the decay rate was only 18% on day 14 storage, which was lower than 52% of RC. During 12 °C and 85% relative humidity (RH) storage, the shelf life of winged bean pods in the FC group was 14.8 days, which was significantly longer than that of the pods in the RC group (10.6 days). In conclusion, FC is an effective precooling method to rapidly remove field heat postharvest and maintain the storage quality of winged beans.

Plasmonic nanostructures offer an enticing prospect in many applications, ranging from lasing to biosensing, due to their unrivaled light concentration beyond the diffraction limit. However, this promise is substantially undercut by the intrinsically high losses in metals. Here, an experimental ultra‐high‐Q plasmon resonance with a linewidth down to 2 nm (Q‐factor ≈ 350) and a resonance intensity of 51% in an ultrasmooth gold nanogroove array is reported. Such an experimental ultranarrow resonance arises from two key factors. First, a geometrical‐induced coupling between the Fabry–Pérot and Wood's anomaly modes significantly suppresses the groove array's radiative damping. Second, an ultrasmooth gold surface fabricated by template stripping minimizes its surface scattering and grain boundary scattering. Benefiting from this ultranarrow resonance, a figure of merit (FOM) of 284 and an FOM* of 617 in refraction index (RI) sensing under normally incident detection are demonstrated, the former of which is the record FOM in all reported broad‐RI‐range plasmonic RI sensors. The array is further demonstrated as a surface thickness sensor for detecting mercaptocarboxylic acids with the surface sensitivity of 0.18 nm/CH2, which suggests that the array is a promising platform for thickness detection of surface analytes and label‐free biomedical sensing. [ABSTRACT FROM AUTHOR]

In this paper, we study the temporal decay properties of weak solutions to the inhomogeneous incompressible Navier–Stokes equations in R n , n = 2 , 3 . The optimal L 2 - decay rate is established, which coincides with that for the classical homogeneous Navier–Stokes system. Additionally the viscosity coefficient is assumed to Lipschitz continuously depend on density without smallness condition, which is a weaker assumption. The initial data u 0 is only required to be in L p (R n) ∩ L 2 (R n) , 1 ≤ p < 2 . [ABSTRACT FROM AUTHOR]

Abstract Aqueous environmental DNA (eDNA) analysis has been applied to the monitoring of various ecosystems and taxa, and the characteristics of aqueous eDNA have been previously studied. In contrast, although sedimentary eDNA has been used to restore past information, the characteristics of sedimentary eDNA are not well understood. In this study, we compared the properties of sedimentary and aqueous eDNA of macro‐organisms. First, to clarify the preservation ability of sediments, we compared the difference in decay rates between aqueous and sedimentary eDNA using samples collected from a biotope (an artificial pond prepared with concrete). Next, to clarify the biological information retained in sedimentary eDNA both qualitatively and quantitatively, we compared eDNA concentrations between sediment and water samples collected simultaneously from a lake, and the fish species detected by eDNA metabarcoding were also compared. The results demonstrated the following: (a) the decay rate (decreased eDNA copy number divided by the initial eDNA copy number per unit time) of sedimentary eDNA (0.00033 ± 0.000049 [mean ± SE]/hr) was lower than that of aqueous eDNA (0.01863 ± 0.0011/hr); (b) sedimentary eDNA concentration of the mitochondrial marker of three fish species was higher than aqueous eDNA concentration for the same sample weight (12.5–1,456.9 times); and (c) the species composition obtained by metabarcoding was not significantly different between sediment and water; however, considering the lower decay rate of sedimentary eDNA, using both sample types may provide more comprehensive information of species distribution. Thus, sedimentary eDNA analysis will expand future biomonitoring and ecological studies by providing a difference in timescale.

The paper deals with global existence and blow-up results for a class of fourth-order wave equations with nonlinear damping term and superlinear source term with the coefficient depends on space and time variable. In the case the weak solution is global, we give information on the decay rate of the solution. In the case the weak solution blows up in finite time, estimate the lower bound and upper bound of the lifespan of the blow-up solution, and also estimate the blow-up rate. Finally, if our problem contains an external vertical load term, a sufficient condition is also established to obtain the global existence and general decay rate of weak solutions. [ABSTRACT FROM AUTHOR]

The decomposition of coarse woody debris (CWD) affects the energy flow and nutrient cycling in forest ecosystems. Previous studies on CWD have focused on the input, decomposition, reserve dynamics, and CWD functions, but coarse woody debris decomposition is complex and the results from different regions vary considerably. It is not clear which factors affect decay rate (k), especially at different decomposition stages. In this study, a single-exponential decay model was used to analyze the characteristics of CWD decomposition in Larix gmelinii forests over the 33 years following a fire in the Greater Khingan Mountains. The results show that the decay rate of coarse woody debris was positively correlated to decay class. The average decomposition rate was 0.019, and 41 years and 176 years are needed for a 50% and 95% mass loss, respectively. CWD nutrient content, density, and water content could explain the variance in the decay rate (~ 42%) of the decay factors such as amount of leaching, degree of fragmentation, respiration of the debris, and biotransformation, and varied significantly between different decay classes. Using the space–time substitution method, this study arranged the coarse woody debris of different mortality times to form a 33 year chronosequence which revealed the decomposition process. It was concluded that the decay rate was mainly explained by structural component of the debris and its nitrogen and water contents. This paper quantifies the indicators affecting CWD decay to explain the decomposition process. [ABSTRACT FROM AUTHOR]

Copyright of Shipin Kexue/ Food Science is the property of Food Science Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

We consider the Cauchy problem of a third order in time nonlinear equation known as the Jordan–Moore–Gibson–Thompson (JMGT) equation arising in acoustics as an alternative model to the well-known Kuznetsov equation. We show a local existence result in appropriate function spaces, and, using the energy method together with a bootstrap argument, we prove a global existence result for small data, without using the linear decay. Finally, polynomial decay rates in time for a norm related to the solution will be obtained. [ABSTRACT FROM AUTHOR]

This paper investigates the design problem of the proportional-plus-derivative state feedback fuzzy controller for the Takagi–Sugeno fuzzy singular systems, which considering the influence of internal perturbations and external noises. To solve the perturbation problem in the control system simply and concisely, the benefit of employing a robust control approach is proposed. Considering the perturbed Takagi–Sugeno fuzzy singular systems with external noises, the Lyapunov stability theory is chosen to derive the stability conditions with passivity constraints. To bring better transient performance for the controlled systems, the decay rate constraint is also adopted. These sufficient stability conditions can be effectively transferred into the linear matrix inequality problem. Finally, an example is used to verify the proposed robust fuzzy controller design method's applicability and effectivity. [ABSTRACT FROM AUTHOR]

Abstract This paper deals with a class of Petrovsky system with nonlinear damping w t t + Δ B 2 w − k 2 Δ B w t + a w t | w t | m − 2 = b w | w | p − 2 $$\begin{aligned} w_{tt}+\Delta _{\mathbb{B}}^{2}w-k_{2} \Delta _{\mathbb{B}}w_{t}+aw_{t} \vert w_{t} \vert ^{m-2}=bw \vert w \vert ^{p-2} \end{aligned}$$ on a manifold with conical singularity, where Δ B $\Delta _{\mathbb{B}}$ is a Fuchsian-type Laplace operator with totally characteristic degeneracy on the boundary x 1 = 0 $x_{1}=0$ . We first prove the global existence of solutions under conditions without relation between m and p, and establish an exponential decay rate. Furthermore, we obtain a finite time blow-up result for local solutions with low initial energy E ( 0 ) < d $E(0)< d$ .

Background: Most of the countries are affected with the pandemic outbreak of the coronavirus infection. Understanding the severity and distribution in various regions will help in planning the controlling measures. Objectives: The objective was to assess the distribution and growth rate of COVID-19 infection in Tamil Nadu, India. Methods: The data on the number of infections of COVID-19 have been obtained from the media reports released by the Government of Tamil Nadu. The data contain information on the incidence of the disease for the first 41 days of the outbreak started on March 7, 2020. Log-linear model has been used to estimate the progression of the COVID-19 infection in Tamil Nadu. Separate models were employed to model the growth rate and decay rate of the disease. Spatial Poisson regression was used to identify the high-risk areas in the state. Results: The models estimated the doubling time for the number of cases in growth phase as 3.96 (95% confidence interval [CI]: 2.70, 9.42) days and halving time in the decay phase as 12.08 (95% CI: 6.79, 54.78) days. The estimated median reproduction numbers were 1.88 (min = 1.09, max = 2.51) and 0.76 (min = 0.56, max = 0.99) in the growth and decay phases, respectively. The spatial Poisson regression identified 11 districts as high risk. Conclusion: The results indicate that the outbreak is showing decay in the number of infections of the disease which highlights the effectiveness of controlling measures.

Soil microbes can influence plant competitive outcomes by stabilizing plant community dynamics or mediating plant competitive hierarchies. Which effect dominates depends on whether microbial effects can extend beyond the focal conditioning individual. While it is well known that microbial effects can extend to other individuals through space, we lack an explicit theoretical understanding of the factors that regulate their spread to other individuals in subsequent generations. Here, we examine how the commonly assumed stabilizing effects of host-specific pathogens in fact depend on two factors that allow microbial effects to be cross-generational—which plant demographic vital rate is influenced by microbes and the conditioning and decay rates of soil microbial communities. With a novel patch occupancy model that incorporates the transition of soil states following plant colonization and mortality, we show that host-specific pathogens enable plant coexistence when they suppress conspecific plant colonization of empty patches but contribute to competitive hierarchies when they modify only the mortality and fecundity of the conditioning plant individual. In a series of model extensions, we further demonstrate that these latter microbial effects can still promote coexistence, but only when microbial communities decay slowly following plant death, thereby allowing microbial effects to be cross-generational. Our study calls for further empirical work quantifying the demographic rates most affected by soil microbes as well as the timescales of conditioning and decay. [ABSTRACT FROM AUTHOR]

The present study aims to understand microbial succession and dynamics of dry matter, carbon and nitrogen during the decomposition of leaf litters of Tephrosia candida (Roxb.) DC. and Oryza sativa L. in two fallow lands (FL) of 3 years (FL-3) and 8 years (FL-8) following shifting cultivation in Mizoram. A total of 64 microorganisms were isolated from two leaf litters by seri al dilution method, out of which 13 microbes were identified as decomposers as they exhibited a positive response towards the enzyme activity. Among these 13 microorganisms, 4 (SKT 02, SKT 05, SKT 09 and SKT 020) were bacteria (Streptobacillus sp. and Bacillus sp.), 5 (SKT 033, SKT 034, SKT 035, SKT 040 and SKT045) were fungi (Microsporum sp., Rhizopus sp. and Aspergillus sp.) and 4 (SKT 030, SKT 052, SKT 053 and SKT 060) were actinomycetes (Streptomycetes sp.). T. candida leaf litter possessed low initial Carbon/Nitrogen (8.77) and Lignin/Nitrogen ratio (2.29) and considered a high-quality resource exhibiting higher decomposition rate. Mass loss of carbon and nitrogen (~ 40-80%) was maximum during the initial two months, which slowed down in the later period of decomposition. It was concluded that the number of bacteria, fungi and actinomycetes regulate organic matter and nutrient dynamics in the soil through various enzymatic actions on high- and low-quality litters. The combination of O. sativa and T. candida litter is recommended to manage soil fertility in shifting cultivation of Mizoram, Northeast India. [ABSTRACT FROM AUTHOR]

In this article, the asymptotic behavior of the solution to the following one dimensional Schrödinger equations with white noise dispersionis studied. Here the equation is written in the { Stratonovich} formulation, and is a standard real valued Brownian motion. After establishing the global well-posedness, theoretical proof and numerical investigations are provided showing that, for a deterministic small enough initial data in , the expectation of the norm of the solutions decay to zero at as goes to , as soon as. [ABSTRACT FROM AUTHOR]

Copyright of Food Research & Development is the property of Food Research & Development Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In this paper, we establish general decay estimates of the solution for the Cauchy problem of a Moore–Gibson–Thompson equation with a viscoelastic term using the energy method in the Fourier space. We first discuss the well-posedness. Then we establish our main result and present two illustrative examples by the end. [ABSTRACT FROM AUTHOR]

In this paper, we propose a simple cohesive framework to find an optimal directed control network topology with minimum number of links while a prescribed decay rate is satisfied in the transient response of a distributed control system. In order to guarantee the system’s decay rate to be faster than a prespecified value, a constraint on the dominant eigenvalue of the system is required to be considered. This results in a nonconvex optimization problem as eigenvalue of a parametric nonsymmetric matrix is a nonconvex, nonsmooth, and even non-Lipschitz function. Here, we present a convex equivalent optimization problem whose minimizer also solves this eigenvalue optimization problem. This optimization problem proposes a state-feedback matrix which results in a decay rate faster than a given value while input signal costs are considered. The equivalent optimization problem in combination with sparsity-promoting optimal control constitutes a combinatorial optimization problem. Using alternating direction method of multipliers, the problem is decomposed into a chain of analytically solvable subproblems which are differentiable and separable. The proposed optimization framework includes relative preference between the topology of the control network and the decay rate of the system. The simulation results show the effectiveness of the proposed framework. [ABSTRACT FROM AUTHOR]

In the present paper we consider the Standard Linear Solid model in R N coupled with the Cattaneo law of heat conduction. We show the well-posedness and asymptotic stability of the problem, giving decay rates for a norm related to the solution. These results are compared with those given for the Fourier problem in (Pellicer and Said-Houari (2020)) and the ones of the problem without heat conduction (see previous work (Appl Math. Optim80 (2019) 447–478)). The main difference is that the Cattaneo system exhibits the well-known regularity-loss phenomenon. The methods used to prove these results are the energy method in the Fourier space and the eigenvalues expansion method. [ABSTRACT FROM AUTHOR]

Forest aboveground biomass (AGB) is imperative in the study of climate change and the carbon cycle in the global terrestrial ecosystem. Developing a credible approach to estimate forest biomass and carbon stocks is essential. Four allometric models were used with two optimization algorithms; Modified Root Mean Square Propagation (Modified RMSProp) and Modified Adaptive Moment Estimation (Modified Adam) were also used to train each model. Convergence was achieved after 1000 iterations of Modified RMSProp and 200 iterations of Modified Adam for all the models. A learning rate of 0.01 and exponential decay rates of 0.9 and 0.999 for the first and second momentum. A loss function of 0.5 Mean Square Error (0.5 MSE) was used and Root Mean Square Error (RMSE) was used to judge the accuracy of the models. The study showed that the optimization algorithms were both able to accurately optimize three of the four allometric models. While Modified Adam was the more efficient optimizer, it had the highest RMSE value 2.3910 and Modified RMSProp had the least RMSE value 0.37381. However, there was no statistically significant difference between the accuracy of the models optimized by both algorithms. [ABSTRACT FROM AUTHOR]

Rural areas of developing countries have various indoor air pollution sources along with solid fuels used for cooking. This study aims to compare five indoor air pollution sources, viz., incense stick, dhoop, mosquito coil, cigarette, and cooking fuel charcoal, with respect to their pollution potential. The monitoring of PM, CO, CO2, NO2, and particulate bound heavy metals was carried out. Dhoop (DH1) was found to be emitting the highest concentration of metal Sb among all the analyzed metals. Dhoop, incense sticks, mosquito coil, and charcoal were found to be having high pollution potential. The first-order decay rate equation indicated that the highest decay rate constant per hour was observed with dhoop (DH1) for PM10 and PM2.5 and with mosquito coil (M1) for CO. The highest half-life of PM10 and PM2.5 was observed for cigarette (CG1) and charcoal (C1) respectively indicating their slow decay in air. The average daily dose values indicated that the age group 6 to < 11 years, 11 to < 16 years, and 31 to < 51 years will be more vulnerable to PM emissions from dhoop (DH1) and incense stick (IS1). The highest hazard index was estimated for incense stick (IS1) and charcoal. Significant carcinogenic risk was observed from cigarette and charcoal. The multiple-path particle dosimetry (MPPD) model was used to estimate the deposition of PM fractions in various regions of the human body. [ABSTRACT FROM AUTHOR]

We consider the asymptotic behavior of a linear model arising in fluid-structure interactions. The system is formed by a heat equation and a wave equation in two distinct domains, which are coupled by atransmission condition along the interface of the domains. By means of the frequency domain approach, we establish some decay rates for the whole system. Our results also showthat the decay of the fluid-structure interaction depends not only on the transmission of the damping from the heat equation to the wave equation, but also on the location of the damping for the wave equation. [ABSTRACT FROM AUTHOR]

Environmental DNA (eDNA) analysis has enabled more sensitive and efficient biological monitoring than traditional methods. However, since the target species is not directly observed, interpretation of results cannot preclude process Type I errors. Specifically, there may be a spatial or temporal gap between the target eDNA and the eDNA source in the sampled area. Moreover, eDNA surveillance lacks the ability to distinguish whether eDNA originated from a living or non-living source. This kind of Type I error is difficult to control for, in part, because the relationship between the state of eDNA (i.e., intracellular or extracellular) and the degradation rate is still unclear. Here, we applied PMA (Propidium monoazide) to eDNA analysis which enabled us to differentiate “intact cells” from “disrupted cells.” PMA is a dye that has a high affinity for double-stranded DNA and forms a covalent bond with double-stranded DNA and inhibits amplification of the bonded DNA molecules by PCR. Since PMA is impermeable to the cell membrane, DNA protected by an intact cell membrane can be selectively detected. In this study, we investigated the workability of PMA on vertebrate eDNA using zebrafish, Danio rerio. Aquarium water was incubated for 1 week to monitor the eDNA degradation process of both intracellular and extracellular eDNA. We developed ten species-specific quantitative PCR assays for D. rerio with different amplification lengths that enabled independent quantification of total eDNA (sum of intracellular and extracellular eDNA, commonly measured in other studies) and intracellular eDNA (DNA in intact cells) and allow for analyses of sequence length-dependent eDNA degradation in combination with PMA. We confirmed that PMA is effective at differentiating “intact” and “disrupted” fish cells. We found that total eDNA and intracellular eDNA have different degradation processes that are dependent on the length of target sequence. For future conservation efforts using eDNA analyses, it is necessary to increase the reliability of the analysis results. The research presented here provides new analysis tools that expand our understanding of the ecology of eDNA, so that more accurate and reliable conclusions can be determined.

Estimates of dead and down woody material (DWM) biomass are important for nutrient cycling, wildlife habitat assessment, fire effects and climate change science. Most methods used to sample woody material initially assess volume then estimates of wood density are used to convert volume to biomass. To assess initial wood density and decomposition rate, this study examined in situ wood density of lodgepole pine logs at the Tenderfoot Creek Experimental Forest (TCEF), central Montana, United States, 1, 11, and 22 years after felling. Mean wood density decreased from 0.39 to 0.27 g cm–3 over 22 years and the single exponential decay rate was k = 0.012 yr–1 1 and 11-years post-felling and 0.022 yr–1 11 and 22 years post-felling. A common 5-category decay classification system was evaluated for estimating wood density by decay class, which identified significant difference in three of four observed classes.

Global climate change is driving the expansion of mangroves into saltmarsh habitat, which may alter the rate and magnitude of organic matter decomposition and nutrient cycling due to differences in the structural complexity, litter quality, and other ecophysiological traits of foundation species. This work quantified and compared aboveground litter decomposition of the range-expanding mangrove, Avicennia germinans, and resident saltmarsh cordgrass, Spartina alterniflora, and decomposition of a standard substrate belowground, in the saltmarsh and saltmarsh-mangrove ecotone habitat along the Atlantic coast of Florida, USA. Plant and soil fractions were tested for natural abundances of δ13C and δ15N stable isotopes to elucidate soil nutrient sources. Although aboveground decomposition rates differed between marsh and mangrove species due to differences in litter quality, decomposition rates did not vary between saltmarsh and ecotonal habitats. Decay rates were higher for A. germinans leaf litter (0.007 ± 0.0003 k day−1) than for S. alterniflora (0.004 ± 0.0003 k day−1) regardless of habitat, which suggests that increasing inputs of A. germinans litter with encroachment may increase nutrient availability through rapid turnover. Furthermore, belowground decomposition was similar between habitats (0.015 ± 0.0008 k day−1), whereas soil δ13C and δ15N stable isotopes differed significantly. Collectively, these results suggest that mangrove encroachment may not modify the environmental factors driving decomposition, but alterations in foundation plant species may ultimately alter nutrient cycling within habitats through shifts in litter quality. [ABSTRACT FROM AUTHOR]

In this paper, we establish the Lp-norm (1 < p ≤ ∞) algebraic decay rate of solutions and higher-order derivative of solutions for 3D generalized Hall-MHD systemprovided that the L¹-norm of initial data is sufficiently small and the parameters α ∈ [ 5 4, 2 ],β ∈ [ 7 4, 2 ] . [ABSTRACT FROM AUTHOR]

In this paper, we consider the standard linear solid model in R N coupled with the Fourier law of heat conduction. First, we give the appropriate functional setting to prove the well-posedness of this model under certain assumptions on the parameters (that is, 0 < τ ≤ β ). Second, using the energy method in the Fourier space, we obtain the optimal decay rate of a norm related to the solution. In particular, we prove that when 0 < τ < β the decay rate is the same as in the Cauchy problem without heat conduction (see Pellicer and Said-Houari in Appl Math Optim 80: 447–478, 2019), and that it does not exhibit the well-known regularity loss phenomenon which is present in some of these models. When τ = β > 0 (that is, when the only dissipation comes through the heat conduction), we still have asymptotic stability, but with a slower decay rate. We also prove the optimality of the previous decay rate for the solution itself by using the eigenvalues expansion method. Finally, we complete the results in Pellicer and Said-Houari (Appl Math Optim 80: 447–478, 2019) by showing how the condition 0 < τ < β is not only sufficient but also necessary for the asymptotic stability of the problem without heat conduction. [ABSTRACT FROM AUTHOR]