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We determine the spreading speed of an epidemic model with nonlocal diffusion and free boundary. The model is evolved from a degenerate reaction-diffusion model of Capasso and Maddalena (J Math Biol 13:173–184, 1981), and was studied in Zhao et al. (Commun Pure Appl Anal 19:4599–4620, 2020) recently, where it was shown that as time goes to infinity, the population of the infective agents either vanishes or spreads successfully. In this paper, we show that when spreading is successful, the asymptotic spreading speed is finite or infinite depending on whether a threshold condition is satisfied by the kernel function governing the spatial dispersal of the agents. The proof relies on a rather complete understanding of the associated semi-wave problem and traveling wave problem. For free boundary models, the case of infinite spreading speed, also known as accelerated spreading, is only recently shown to happen in Du et al. (J Math Pure Appl 154:30–66, 2021) for a single species Fisher-KPP model; this paper is the first to show that it happens to a very different two species model with free boundary. This suggests that accelerated spreading is a rather common phenomenon for free boundary problems with nonlocal diffusion. In contrast, for the corresponding models with local diffusion, the spreading can only proceed with finite speed. [ABSTRACT FROM AUTHOR]

This paper is concerned with the propagation phenomena for a nonlocal dispersal Lotka–Volterra competition model with shifting habitats. It is assumed that the growth rate of each species is nondecreasing along the x-axis, positive near ∞ and nonpositive near - ∞ , and shifting rightward with a speed c > 0 . In the case where both species coexist near ∞ , we established three types of forced waves connecting the origin, respectively to the coexistence state with any forced speed c; to itself with forced speed c > c ∗ (∞) ; and to a semi-trivial steady state with forced speed c > c ¯ (∞) , where c ∗ (∞) and c ¯ (∞) are two positive numbers. In the case where one species is competitively stronger near ∞ , we also obtain the existence and nonexistence of forced waves connecting the origin to the semi-trivial steady state. Our results show the existence of multiple types of forced waves with the same forced speed. The mathematical proofs involve integral equations and Schauder's fixed point theorem, and heavily rely on the construction of various upper-lower solutions, which adds new techniques to deal with the "shifting environments" problem. [ABSTRACT FROM AUTHOR]

Objectives: The study aimed to explore the association of sarcopenia and vitamin D deficiency with glucocorticoid-induced osteoporosis (GIOP) in Chinese patients with rheumatoid arthritis (RA). Method: Skeletal muscle mass, serum 25(OH)D levels, and bone mineral density (BMD) were assessed. Results: The prevalence of OP, sarcopenia, and vitamin D deficiency in RA patients was significantly higher than in controls (all P < 0.001). The percentage of GC use was 56.9%, and the prevalence of GIOP was 38.1% in 480 RA patients. The prevalence of OP in RA patients without sarcopenia was lower than that in RA patients with sarcopenia (P < 0.05). In RA patients with and without GC, the prevalence of OP in patients without sarcopenia was significantly lower than that in patients with sarcopenia (P < 0.001 and P < 0.05). Female sex (OR = 54.737; 95% CI: 7.103–421.809; P < 0.0001), age (OR = 1.078; 95% CI: 1.048–1.110; P < 0.0001), sarcopenia, and vitamin D deficiency (OR = 2.250; 95% CI: 1.246–64.065; P = 0.007) were risk factors for GIOP in RA patients. Conclusions: GIOP is associated with sarcopenia and vitamin D deficiency and is widespread among Chinese patients with RA. Key points ·Percentage of using GC and the prevalence of OP were all high in Chinese patients with RA. ·GIOP was widely existed in Chinese RA patients, which was associated with sarcoprnia and vitamin D deficiency. [ABSTRACT FROM AUTHOR]

This paper is concerned with the spatial propagation of bistable nonlocal dispersal equations in exterior domains. We first obtain the existence and uniqueness of an entire solution which behaves like a planar traveling wave front for large negative time. Then, when the entire solution comes to the interior domain, the profile of the front will be disturbed. However, the disturbance is local in space for finite time, which means the disturbance disappears as its location is far away from the interior domain. Furthermore, we prove that the solution can gradually recover its planar wave profile uniformly in space and continue to propagate in the same direction for large positive time provided that the interior domain is compact and convex. Our work generalizes the local (Laplace) diffusion results obtained by Berestycki et al. (2009) to the nonlocal dispersal setting by using new known Liouville results and Lipschitz continuity of entire solutions due to Li et al. (2010). [ABSTRACT FROM AUTHOR]

Background: Currently, there is no generally approved surgical treatment for patients with primary angle-closure glaucoma (PACG) and co-existing cataracts. The aim of this systematic review and meta-analysis was to compare the efficacy and safety of phacoemulsification and phacotrabeculectomy in PACG patients with cataract. Methods: Diverse databases were searched, including PubMed, MEDLINE, EMBASE, Cochrane Library, Chinese Journal Full-text Database (CNKI), Wanfang database, and China Science and Technology Journal Database, for randomized controlled trials (RCTs) on phacoemulsification and phacotrabeculectomy for the treatment of PACG published up to 30 June 2021. ReviewManager (RevMan) version 5.4 software was used for the meta-analysis, and the effective quantity of measurement data was measured by the mean difference (MD) and 95% confidence interval (CI). The effect of counting data was measured by odds ratio (OR). Results: Our search of the databases identified 14 RCTs that satisfied the search criteria. Meta-analysis of these 14 RCTs showed that at the 1 month postoperative follow-up, intraocular pressure (IOP) of patients in the phacoemulsification group was higher than that of patients in the phacotrabeculectomy group (MD 2.04, 95% CI 1.42–2.65; P < 0.00001). However, the postoperative IOP was not significantly different between the two groups at the 3, 6, and 12 months postoperative follow-ups (P = 0.52, P = 0.51, and P = 0.05, respectively). More medications for IOP reduction were required by patients in the phacoemulsification group compared with those in the phacotrabeculectomy group at 3 months postoperation (MD 0.76, 95% CI 0.33–1.18; P = 0.0005), 6 months postoperation (MD 0.66, 95% CI 0.15–1.18; P = 0.01), and 12 months postoperation (MD 0.76, 95% CI 0.22–1.30; P = 0.006). Patients in the phacoemulsification group obtained better best corrected visual acuity (BCVA) than those in the phacotrabeculectomy group (MD − 0.17, 95% CI − 0.34 to − 0.01; P = 0.04) at 3 months postoperation, but there was no significant difference in BCVA between the two groups at 6 and 12 months postoperation (P = 0.33 and P = 0.56, respectively). The deepened anterior chamber was more obvious in patients in the phacoemulsification group versus those in the phacotrabeculectomy group (MD 0.61, 95% CI 0.03–1.18; P = 0.04). Patients in the phacoemulsification group experienced fewer postoperative complications than those in the phacotrabeculectomy group (OR 0.27, 95% CI 0.17–0.42; P < 0.00001). Conclusion: Our results provide evidence that phacotrabeculectomy has advantages over phacoemulsification for the treatment of PACG in terms of better IOP and reduced medication need during the early stage post surgery. However, in terms of the complication risk, phacoemulsification is the more secure treatment option. [ABSTRACT FROM AUTHOR]

This paper is devoted to considering entire solutions of the following two-species Lotka–Volterra strong competition system with nonlocal dispersals 0.1 u t = ∫ R k (x - y) u (y , t) d y - u + u 1 - u - a v , x ∈ R , t ∈ R , v t = d ∫ R k (x - y) v (y , t) d y - d v + r v 1 - v - b u , x ∈ R , t ∈ R , where a > 1 , b > 1 , d, and r are positive constants. By constructing appropriate super- and sub-solutions, and with the aid of corresponding comparison principle, we established the existence and related qualitative properties of entire solutions originating from three and four traveling wave solutions. Meanwhile, we considered the non-existence of entire solutions originating from more than seven traveling fronts by introducing the definition of non-extendable (terminated) sequence. Compared to the known works for Lotka–Volterra competition system with classical diffusions, we have to overcome many difficulties due to the appearance of nonlocal dispersal operators in current paper. [ABSTRACT FROM AUTHOR]

In this paper, we focus on the propagation phenomena of a bistable man–environment epidemic model with nonlocal dispersals, where there exists a positive feedback interaction between the concentration of infectious agent and infectious human population. The monostable and bistable traveling wave solutions and three-wave entire solutions are studied. First, by applying and developing the known results for monostable case, we give a summary of the existence and asymptotic behavior of all monostable traveling wave solutions in two different monostable intervals and further find some relationship between them. The existence of bistable traveling wave solutions is obtained by introducing the results about monotone semiflows with weak compactness. Second, we give twelve types of three-wave entire solutions, which contain all possibilities of three-wave entire solutions originating from three traveling wave solutions with different nonzero wave speeds, by constructing new auxiliary functions and super- and sub-solutions for every type. We also show that these entire solutions are globally Lipschitz continuous with respect to spatial variable. In addition, the nonexistence result of entire solutions originating from more than four traveling wave solutions is obtained. [ABSTRACT FROM AUTHOR]

Recent molecular research has revealed the significance of hybridization and reticulate evolution in the evolution of temperate woody bamboos at both intergeneric and intrageneric levels. Although the monophyly of Fargesia s.l. is debated, species of Fargesia s.l. with the spathe-like leaf sheath syndrome form a clade as the Fargesia spathacea complex. A previous study showed varying degrees of genetic diversity and an excess of heterozygotes across the F. spathacea complex, but phylogenetic relationships within this complex remain unclear. Here, we sampled 24 populations and 72 individuals of the F. spathacea complex and three outgroups: Yushania confusa, Fargesia setosa, and Bashania fargesii. Using phylogenomic data, we generated a robust phylogeny and explored the implications of the phylogeny for previous hybridization and introgression hypotheses. The phylogenetic analyses suggested that the 72 individuals were clustered into four major clades consistent with the genetic structure but different from the statistical results of vegetative traits. Our phylogenetic and biographical evidence demonstrate that the species in the F. spathacea complex originated outside the Hengduan Mountains region and spread to heterogeneous mountain habitats in the Daba and Qinling Mountains. In addition, adaptive radiation to cold climates and reticulate evolution may have driven species diversification within the F. spathacea complex, making it difficult to classify at the population level. [ABSTRACT FROM AUTHOR]

In this paper, curved fronts are constructed for spatially periodic bistable reaction-diffusion equations under the a priori assumption that there exist pulsating fronts in every direction. Some sufficient and some necessary conditions of the existence of curved fronts are given. Furthermore, the curved front is proved to be unique and stable. Finally, a curved front with varying interfaces is also constructed. Despite the effect of the spatial heterogeneity, the result shows the existence of curved fronts for spatially periodic bistable reaction-diffusion equations which is known for the homogeneous case. [ABSTRACT FROM AUTHOR]

Aiming at extending the classical strong mathematical morphology operations to quantum image processing field, in this paper, an quantum image edge detection method is designed based on the novel enhanced quantum representation of digital images (NEQR) and multi-directions Gray-scale morphology. Because NEQR is more convenient for gray operation of quantum image. In addition, based on multi-directional feature of image edges, the multi-directional structures are constructed by combining the mathematical morphology. Compared with the existing quantum image edge detection methods, this method can reach a better effect. [ABSTRACT FROM AUTHOR]

In this paper, we lock the focus in effect of P T -symmetric operation on the dynamics of concurrence and the first-order coherence for Heisenberg XY model. We discover the complementarity between concurrence and the first-order coherence. And the complementarity indicates that P T -symmetric operation induces enhancement of coherence at the expense of concurrence loss in Heisenberg XY model. Meanwhile, we find that coherence under P T -symmetric operation can be recovred in a certain range of time dependent parameter, thus we can choose some special P T -symmetric operation to make the coherence maximum. Our analysis yields the result that the quadratic sum of these two resources can be improved via P T -symmetric operation. Both temperature and parameter of P T -symmetric operation will change the magnitude of the increment in the quadratic sum of concurrence and the first-order coherence. [ABSTRACT FROM AUTHOR]

This paper deals with the semilinear elliptic problem - Δ u = λ m (x) u - [ a (x) + ε b (x) ] u p in Ω , B u = 0 on ∂ Ω , where p > 1 , λ > 0 , m , a , b ∈ C (Ω ¯) , with a ⪈ 0 , b ⪈ 0 , Ω is a bounded C 2 domain of R N ( N ≥ 1 ), B is a general classical mixed boundary operator, and ε ≥ 0 . Thus, a(x) and b(x) can vanish on some subdomain of Ω and the weight function m(x) can change sign in Ω . Through this paper we are always considering classical solutions. First, we characterize the existence of positive solutions of this problem in the special case when ε = 0 . Then, we investigate the sharp patterns of the positive solutions when ε ↓ 0 and ε ↑ ∞ . Our study reveals how the existence of sharp profiles is determined by the behavior of b(x). [ABSTRACT FROM AUTHOR]

We study the processes K K ¯ → ϕ , π D → D ∗ , π D ¯ → D ¯ ∗ , and the production of ψ (3770) , ψ (4040) , ψ (4160) , and ψ (4415) mesons in collisions of charmed mesons or charmed strange mesons. The process of 2-to-1 meson–meson scattering involves a quark and an antiquark from the two initial mesons annihilating into a gluon and subsequently the gluon being absorbed by the spectator quark or antiquark. Transition amplitudes for the scattering process derive from the transition potential in conjunction with mesonic quark–antiquark wave functions and the relative-motion wave function of the two initial mesons. We derive these transition amplitudes in the partial wave expansion of the relative-motion wave function of the two initial mesons so that parity and total-angular-momentum conservation are maintained. We calculate flavor and spin matrix elements in accordance with the transition potential and unpolarized cross sections for the reactions using the transition amplitudes. Cross sections for the production of ψ (4040) , ψ (4160) , and ψ (4415) relate to nodes in their radial wave functions. We suggest the production of ψ (4040) , ψ (4160) , and ψ (4415) as probes of hadronic matter that results from the quark–gluon plasma created in ultrarelativistic heavy-ion collisions. [ABSTRACT FROM AUTHOR]

The sandy soil leaks water and fertilizer, and the ecological degradation is serious. The structural characteristics of soft rock and sandy soil are complementary, and the improvement of sandy soil by adding soft rock is of great significance to improve soil fertility, restore biodiversity, and maintain sustainable development of the Mu Us sandy land region. In this study, total organic carbon (TOC), particulate organic carbon (POC), dissolved organic carbon (DOC), easily oxidized organic carbon (ROC), microbial biomass carbon (SMBC), bacterial community structure and crop yield were examined using soft rock:sand volume ratios of 0:1 (CK), 1:5 (C1), 1:2 (C2) and 1:1 (C3). Our results indicated that, compared with the CK treatment, TOC (9.66–22.34%), POC (85.65–120.41%) and ROC (114.12–192.31%) noticeably increased in C1, C2 and C3 treatments; SMBC in treatment C3 increased by 42.77%. The three dominant bacteria in the soil (Proteobacteria, Actinobacteria and Chloroflexi), as well as Proteobacteria abundance, greatly declined in the treatments with the addition of soft rock. Pseudarthrobacter was the dominant Genus in all treatments, having an abundance between 11.83 and 19.33%. Bacterial diversity, richness and evenness indices all recorded an increase under the treatments. POC, TOC and SMBC recorded the most significant effects on the bacterial community structure. The largest increases in wheat and corn yields were recorded in the C2 treatment (16.05% and 16.30%), followed by the C1 treatment (8.28% and 8.20%, respectively). Our findings indicate that a soft rock:sand ratio between 1:5 and 1:2 recorded the most improvement in the sandy soil environment. [ABSTRACT FROM AUTHOR]

We mainly consider the stability and reconstruction of convolution random sampling in multiply generated shift-invariant subspaces V p (Φ) = ∑ k ∈ Z d c (k) T Φ (· - k) : (c (k)) k ∈ Z d ∈ (ℓ p (Z d)) r of L p (R d) , 1 < p < ∞ , where Φ = (ϕ 1 , ϕ 2 , … , ϕ r) T with ϕ i ∈ L p (R d) and c = (c 1 , c 2 , … , c r) T with c i ∈ ℓ p (Z d) , i = 1 , 2 , … , r . The sampling set { x j } j ∈ N is randomly chosen with a general probability distribution over a bounded cube C K and the samples are the form of convolution { f ∗ ψ (x j) } j ∈ N of the signal f. Under some proper conditions for the generator Φ , convolution function ψ and probability density function ρ , we first approximate V p (Φ) by a finite dimensional subspace V N p (Φ) = ∑ i = 1 r ∑ | k | ≤ N c i (k) ϕ i (· - k) : c i ∈ ℓ p ([ - N , N ] d). Then we show that the sampling stability holds with high probability for all functions in certain compact subsets V K p (Φ) = f ∈ V p (Φ) : ∫ C K | f ∗ ψ (x) | p d x ≥ (1 - δ) ∫ R d | f ∗ ψ (x) | p d x of V p (Φ) when the sampling size is large enough. Finally, we prove that the stability is related to the properties of the random matrix generated by { ϕ i ∗ ψ } 1 ≤ i ≤ r and give a reconstruction algorithm for the convolution random sampling of functions in V N p (Φ) . [ABSTRACT FROM AUTHOR]

Objectives: To estimate the safety and effectiveness of emergent transjugular intrahepatic portosystemic shunt (TIPS) creation for acute variceal bleeding (AVB) in cirrhotic patients with hepatocellular carcinoma (HCC). Materials and methods: Data of thirty-three patients with AVB and HCC undergoing emergent TIPS creation from January 2016 to January 2022 were enrolled and were retrospectively analyzed. The primary outcomes were the safety of emergent TIPS creation, the bleeding control rate, and the rebleeding rate. The secondary outcomes included overall survival (OS), liver function, overt hepatic encephalopathy (HE), and shunt dysfunction. Results: Emergent TIPS creation was technically successful in 33 patients (100%) and one (3.0%) patient suffered a major procedure-related adverse event. The control rate of bleeding (within 5 days) was 100%. During a median follow-up period of 26.3 months, rebleeding occurred in 6 (18.2%) patients. The median OS was 20.0 months. The 6-week and 1-year survival rates were 87% and 65%, respectively. Laboratory tests showed no significant impairment of liver function following TIPS creation. The incidences of overt HE and shunt dysfunction were 24.2% and 6.1%, respectively. Conclusion: Emergent TIPS creation is feasible and effective for treatment of AVB in cirrhotic patients with HCC. [ABSTRACT FROM AUTHOR]

This paper is devoted to the study of propagation dynamics for a time periodic nonlocal dispersal model with stage structure. In the case where the birth rate function is monotone, we establish the existence of the spreading speed and its coincidence with the minimal wave speed for monotone periodic traveling waves by appealing to the theory developed for monotone semiflows. In the case where the birth rate function is non-monotone, we first obtain the spreading properties by the squeezing technique combined with some known results for the monotone case, and then investigate the existence of periodic traveling waves by using the asymptotic fixed point theorem due to the lack of parabolic estimates and compactness. Finally, we apply the general results to the Nicholson's blowflies model for its spatial dynamics. [ABSTRACT FROM AUTHOR]

Hydrogels as drug carriers for delivery of antibiotics are rarely derived from natural molecules and often require complicated synthesis. Puerarin is an herbal natural product that can self-assemble to form pH-sensitive hydrogels without any structural modification. However, Puerarin hydrogels have poor thermostability and weak mechanical strength. In this work, we prepared N-(9-fluorenylmethoxycarbonyl)-l-phenylalanine (Fmoc–Phe–OH) nanofiber-reinforced Puerarin hydrogels with good mechanical and antibacterial properties for suitable drug carriers. The phase transition temperature of Puerarin hydrogels can be increased from 35 to 55 °C by adding only 6 mg/mL of Fmoc–Phe–OH. Rheological study indicated that the presence of Fmoc–Phe–OH not only increased the storage modulus of Puerarin hydrogels by five times, but also did not affect their pH sensitivity. SEM study and pore analysis indicated that Fmoc–Phe–OH nanofibers intertwined with the Puerarin assembly, leading to enhancement of mechanical property of hydrogel. Antibacterial test indicated that the reinforced Puerarin hydrogels have antibacterial property compared with Puerarin hydrogels. Based on these features, a controllable release of loaded model drug (berberine hydrochloride) can be realized from the reinforced Puerarin hydrogels, showing a good synergistic antimicrobial effect on the S. aureus. [ABSTRACT FROM AUTHOR]

This paper is concerned with a Lotka–Volterra competition system with advection in a periodic habitat ∂ u 1 ∂ t = d 1 (x) ∂ 2 u 1 ∂ x 2 - a 1 (x) ∂ u 1 ∂ x + u 1 b 1 (x) - a 11 (x) u 1 - a 12 (x) u 2 , ∂ u 2 ∂ t = d 2 (x) ∂ 2 u 2 ∂ x 2 - a 2 (x) ∂ u 2 ∂ x + u 2 b 2 (x) - a 21 (x) u 1 - a 22 (x) u 2 , t > 0 , x ∈ R , where d i (·) , a i (·) , b i (·) , a ij (·) (i , j = 1 , 2) are L-periodic functions in C ν (R) for some L > 0 . Under certain assumptions, the system is bistable between two (linearly) stable periodic steady state solutions (0 , u 2 ∗ (x)) and (u 1 ∗ (x) , 0) . We establish the existence of pulsating traveling front (U 1 (x , x + c t) , U 2 (x , x + c t)) connecting (0 , u 2 ∗ (x)) to (u 1 ∗ (x) , 0) . Furthermore, we confirm that the pulsating traveling front is globally asymptotically stable for wave-like initial values. We finally show that such pulsating traveling front is unique (up to translation). The methods involve the sub- and supersolutions, spreading speeds of monostable systems, and the monotone semiflows approach. From the biological point of view, this kind of pulsating traveling front provides a spreading way for two strongly competing species interacting in a heterogeneous habitat. [ABSTRACT FROM AUTHOR]

This paper mainly focuses on the entire solutions of a nonlocal dispersal equation with asymmetric kernel and bistable nonlinearity. Compared with symmetric case, the asymmetry of the dispersal kernel function makes more diverse types of entire solutions since it can affect the sign of the wave speeds and the symmetry of the corresponding nonincreasing and nondecreasing traveling waves. We divide the bistable case into two monostable cases by restricting the range of the variable, and obtain some merging-front entire solutions which behave as the coupling of monostable and bistable waves. Before this, we characterize the classification of the wave speeds so that the entire solutions can be constructed more clearly. Especially, we investigate the influence of the asymmetry of the kernel on the minimal and maximal wave speeds. [ABSTRACT FROM AUTHOR]

This paper is concerned with the spatial dynamics of a nonlocal dispersal population model in a shifting environment where the favorable region is shrinking. It is shown that the species becomes extinct in the habitat if the speed of the shifting habitat edge c>c∗(∞), while the species persists and spreads along the shifting habitat at an asymptotic speed c∗(∞) if c, where c∗(∞) is determined by the nonlocal dispersal kernel, diffusion rate and the maximum linearized growth rate. Moreover, we demonstrate that for any given speed of the shifting habitat edge, the model system admits a nondecreasing traveling wave with the wave speed at which the habitat is shifting, which indicates that the extinction wave phenomenon does happen in such a shifting environment. [ABSTRACT FROM AUTHOR]

Trichoderma reesei (syn. Hypocrea jecorina) is a filamentous ascomycete. Due to its capability of producing large amounts of lignocellulolytic enzymes and various heterologous proteins, this fungus has been widely used for industrial applications for over 70 years. It is also a model organism for lignocellulosic biomass degradation and metabolic engineering. Recently, we experimentally and computationally demonstrated that Trichoderma reesei exhibits high homology pairing and repeat-induced point (RIP) mutation activities at a premeiotic stage, i.e., between fertilization and karyogamy or premeiotic DNA replication. The discovery of RIP in Trichoderma reesei not only reveals significant impacts of sexual reproduction on evolution and chromosome architecture but also provides intriguing perspectives for industrial strain improvement. This review emphasizes two major points about RIP and RIP-like processes in Pezizomycotina fungi. First, the molecular mechanisms of RIP and RIP-like processes in Trichoderma reesei and other Pezizomycotina fungi are apparently distinct from those originally described in the model fungus Neurospora crassa. Second, orthologs of the rid1 (deficient in RIP-1) DNA methyltransferase gene were shown to be essential for sexual development in at least four Pezizomycotina fungi, including Trichoderma reesei. In contrast, rid1 is dispensable for Neurospora crassa sexual development. We suggest that the rid1-like gene products and/or their DNA methyltransferase activities play critical roles in promoting fungal sexual development. The Neurospora crassa rid1 gene might have lost this evolutionarily conserved function. [ABSTRACT FROM AUTHOR]

This paper is concerned with time periodic traveling curved fronts for periodic Lotka-Volterra competition system with diffusion in two dimensional spatial space where $$\Delta $$ denotes $$\frac{\partial ^{2}}{\partial x^{2} }+ \frac{\partial ^{2}}{\partial y^{2} }$$ , $$x,y\in {\mathbb {R}}$$ and $$d>0$$ is a constant, the functions $$r_i(t),a_i(t)$$ and $$b_i(t)$$ are T-periodic and Hölder continuous. Under suitable assumptions that the corresponding kinetic system admits two stable periodic solutions ( p( t), 0) and (0, q( t)), the existence, uniqueness and stability of one-dimensional traveling wave solution $$\left( \Phi _{1}(x+ct,t),\Phi _{2}(x+ct,t)\right) $$ connecting two periodic solutions ( p( t), 0) and (0, q( t)) have been established by Bao and Wang ( J Differ Equ 255:2402-2435, 2013) recently. In this paper we continue to investigate two-dimensional traveling wave solutions of the above system under the same assumptions. First, we establish the asymptotic behaviors of one-dimensional traveling wave solutions of the system at infinity. Using these asymptotic behaviors, we then construct appropriate super- and subsolutions and prove the existence and non-existence of two-dimensional time periodic traveling curved fronts. Finally, we show that the time periodic traveling curved front is asymptotically stable. [ABSTRACT FROM AUTHOR]

This paper is concerned with the spreading (persistence) and vanishing (extinction) of a disease which is characterized by a diffusive SIRS model with a bilinear incidence rate and free boundary. Through discussing the dynamics of a free boundary problem of an SIRS model, the spreading of a disease is described. We get the sufficient conditions which ensure the disease spreading or vanishing. In addition, the estimate of the expanding speed is also given when the free boundaries extend to the whole $$\mathbb {R}$$ . [ABSTRACT FROM AUTHOR]

Electrochemical reduction of nitrate using Fe cathode and Ti/TiO nanotube array anode in dual-chamber cell was investigated. The performance of different cathodes for nitrate removal were in the order of Fe>Al>Cu>Ni. The nitrate removal in dual-chamber cell (99.8%) was much higher than that in single-chamber cell (84.3%) with Fe cathode in 2.5 h. In dual-chamber cell, the highest nitrate removal was obtained at the current density of 15 mA/cm. The nitrate reduction followed first-order kinetics. With increasing initial nitrate concentration, the reduction rate constant slightly decreased from 2.2 h (100.0 mg/L) to 0.9 h (1000.0 mg/L), of which a remarkable nitrate removal of 88.3% could still be achieved with 1000.0 mg/L nitrate. In the presence of 0.5 g/L NaCl, simultaneous reduction of nitrate and oxidation of by-products of ammonia and nitrite were achieved in dual-chamber cell with Fe cathode, of which the nitrate removal rate was 94.3% and no by-products were detected in the solution. Graphical Abstract: [ABSTRACT FROM AUTHOR]

The CRISPR-Cas (CRISPR together with CRISPR-associated proteins) modules are the adaptive immune system, acting as an adaptive and heritable immune system in bacteria and archaea. CRISPR-based immunity acts by integrating short virus sequences in the cell's CRISPR locus, allowing the cell to remember, recognize, and clear infections. In this study, the homology of CRISPRs sequence in BIMs (bacteriophage-insensitive mutants) of Streptococcus thermophilus St-I were analyzed. Secondary structures of the repeats and the PAMs (protospacer-associated motif) of each CRISPR locus were also predicted. Results showed that CRISPR1 has 27 repeat-spacer units, 5 of them had duplicates; CRISPR2 has one repeat-spacer unit; CRISPR3 has 28 repeat-spacer units. Only BIM1 had a new spacer acquisition in CRISPR3, while BIM2 and BIM3 had no new spacers' insertion, thus indicating that while most CRISPR1 were more active than CRISPR3, new spacer acquisition occurred just in CRSPR3 in some situations. These findings will help establish the foundation for the study of CRSPR-Cas systems in lactic acid bacteria. [ABSTRACT FROM AUTHOR]

Correction to: Arch Rational Mech Anal https://doi.org/10.1007/s00205-021-01711-x In this article the affiliation "School of Mathematics and Statistics, Lanzhou University, Lanzhou, China" for Author Zhi-Cheng Wang was missing. Furthermore, in the footnote of the first page of this article the grant number relating to the National Natural Science Foundation of China given for Zhi-Cheng Wang was incorrectly given as 11371179 and should have been 12071193. The original article can be found online at https://doi.org/10.1007/s00205-021-01711-x. [Extracted from the article]

In the present work, we report for the first time the formation of a dominant Dillamore orientation in a multilayered high-purity aluminum (99.99 %) subjected to an ultra-high von Mises strain of 11.2 by accumulative roll bonding (ARB). This multilayered aluminum with an average layer thickness of 180 nm was produced from an original aluminum sheet thickness of 100 μm. Microstructure and texture evolutions during ARB processes were investigated in detail and the formation of a dominant orientation is explained. The grain boundary spacing was observed to reduce with increasing number of ARB cycles. However, after 8 ARB cycles, the average grain boundary spacing was measured to be larger than the theoretical layer thickness. Also, a single and strong Cu orientation formed after an intermediate number (8-12) of ARB cycles, which rotated to a dominant Dillamore orientation with further ARB cycles. This is rationalized on the basis of three mechanisms: First, a homogeneous deformation causing lamella structure formation; second, the enhanced dynamic recovery of this pure aluminum through the movement of Y-type triple junction boundaries, resulting in grain coarsening; and third, the coarsening process eliminating the original few and small Brass and S lamellae and simultaneously enhancing the Cu and Dillamore orientations. [ABSTRACT FROM AUTHOR]

We previously reported that SIRT1, an NAD-dependent deacetylase belonging to the class III histone deacetylases, enhances hepatitis virus B (HBV) replication by targeting the transcription factor AP-1. However, the potential antiviral effects of nicotinamide, a SIRT1 inhibitor, have not yet been explored. In this study, we show that nicotinamide exhibits potent anti-HBV activity with little cytotoxicity. Nicotinamide suppressed both HBV DNA replicative intermediates and 3.5-kb mRNA expression. Moreover, nicotinamide treatment also suppressed core protein expression and the secretion of the hepatitis B surface antigen (HBsAg) and the hepatitis B e antigen (HBeAg) in HBV-expressing cell models. Importantly, nicotinamide treatment suppressed serum HBV DNA, HBsAg and HBeAg levels and liver HBV DNA in HBV-transgenic mice. Furthermore, using a dual-luciferase reporter assay, it was found that nicotinamide exhibited a marked inhibitory effect on the HBV core, SpI, SpII and X promoters, accompanied by decreased expression of the transcription factors AP-1, C/EBPα and PPARα. Therefore, nicotinamide suppresses HBV replication in vitro and in vivo by diminishing HBV promoter activity. This study highlights the potential application of nicotinamide in HBV therapy. [ABSTRACT FROM AUTHOR]

This paper deals with entire solutions of a nonlocal dispersal epidemic model. Unlike local (random) dispersal problems, a nonlocal dispersal operator is not compact and the solutions of nonlocal dispersal system studied here lack regularity in suitable spaces, which affects the uniform convergence of the solution sequences and the technique details in constructing the entire solutions. In the monostable case, some new types of entire solutions are constructed by combining leftward and rightward traveling fronts with different speeds and a spatially independent solution. In the bistable case, the existence of many different entire solutions with merging fronts are proved by constructing different sub- and super-solutions. Various qualitative features of the entire solutions are also investigated. A key idea is to characterize the asymptotic behaviors of the traveling wave solutions at infinite in terms of appropriate sub- and super-solutions. Finally, we also obtain the smoothness of the entire solutions in space, i.e., the solutions established in our paper are global Lipschitz continuous in space. [ABSTRACT FROM AUTHOR]

A susceptible-infected-susceptible almost periodic reaction-diffusion epidemic model is studied by means of establishing the theories and properties of the basic reproduction ratio $${R_{0}}$$ . Particularly, the asymptotic behaviors of $${R_{0}}$$ with respect to the diffusion rate $${D_{I}}$$ of the infected individuals are obtained. Furthermore, the uniform persistence, extinction and global attractivity are presented in terms of $${R_{0}}$$ . Our results indicate that the interaction of spatial heterogeneity and temporal almost periodicity tends to enhance the persistence of the disease. [ABSTRACT FROM AUTHOR]

Cuttage propagation involves adventitious root formation induced by auxin. In our previous study, Larix kaempferi BABY BOOM 1 (LkBBM1), which is known to regulate adventitious root formation, was affected by auxin. However, the relationship between LkBBM1 and auxin remains unclear. Auxin response factors (ARFs) are a class of important transcription factors in the auxin signaling pathway and modulate the expression of early auxin-responsive genes by binding to auxin response elements. In the present study, we identified 14 L. kaempferi ARFs (LkARFs), and found LkARF7 and LkARF19 bound to LkBBM1 promoter and enhanced its transcription using yeast one-hybrid, ChIP-qPCR, and dual-luciferase assays. In addition, the treatment with naphthalene acetic acid promoted the expression of LkARF7 and LkARF19. We also found that overexpression of these two genes in poplar promoted adventitious root formation. Furthermore, LkARF19 interacted with the DEAD-box ATP-dependent RNA helicase 53-like protein to form a heterodimer to regulate adventitious root formation. Altogether, our results reveal an additional regulatory mechanism underlying the control of adventitious root formation by auxin. Overexpression of the transcription factors LkARF7 and LkARF19 promote adventitious root (AR) formation in a heterologous poplar model by positively regulating LkBBM1, providing further insight into the mechanisms of AR development. [ABSTRACT FROM AUTHOR]

This paper is concerned with the nonlinear stability of traveling wavefronts for a single species population model with nonlocal dispersal and age structure. By using the weighted energy method together with the comparison principle, we prove that the traveling wavefront is exponentially stable, when the initial perturbation around the wavefronts decays exponentially at –∞, but it can be arbitrarily large in other locations. In particular, our result implies that the time delay is harmless for stability of traveling wavefronts of the model. [ABSTRACT FROM AUTHOR]

We obtain the exact orders of the complexity of the integration of functions from Besov classes B B p , θ Ω on the unit sphere of d-dimensional Euclidean space in the deterministic and randomized settings. The corresponding optimal quadrature rules have been constructed in both settings. Our results show that Monte Carlo algorithm can provide a faster convergence rate than that of the deterministic one. Quantitatively, the improvement amounts to the factors N - 1 / 2 for 2 ≤ p ≤ ∞ and N - 1 + 1 / p for 1 < p < 2 , where N is the number of function evaluations involved into the computational process. [ABSTRACT FROM AUTHOR]

In this paper, we first study the existence of transition fronts (generalized traveling fronts) for reaction-diffusion equations with the spatially heterogeneous bistable nonlinearity. By constructing sub-solution and super-solution we then show that transition fronts are globally exponentially stable for the solutions of the Cauchy problem. Furthermore, we prove that transition fronts are unique up to translation in time by using the monotonicity in time and the exponential decay of such transition fronts. [ABSTRACT FROM AUTHOR]

Flow characteristics in the near wake of two identical side-by-side circular cylinders located close to a fully developed turbulent boundary layer are investigated experimentally using the particle image velocimetry (PIV) and the pressure sensor. The Reynolds number based on the cylinder diameter ( D) is 1,696, the boundary layer thickness is 6.6 D, the cylinder center-to-center spacing ( T) is varied from T/ D = 1 to 1.906, and the gap spacing between the lower cylinder and the wall ( G) is varied from G/ D = 0 to 1.811. To study the effects of changing the gap ratios of T/ D and G/ D on the wake flow, various wake characteristics such as averaged streamlines, Reynolds stress and vorticity contours as well as other key flow features including the length scales and the Strouhal number are investigated for different ratios of T/ D and G/ D. According to these wake characteristics, five basic flow patterns have been identified. [ABSTRACT FROM AUTHOR]

This paper is concerned with a two-species predator-prey reaction-diffusion system with Beddington-DeAngelis functional response and subject to homogeneous Neumann boundary conditions. By linearizing the system at the positive constant steady-state solution and analyzing the associated characteristic equation in detail, the asymptotic stability of the positive constant steady-state solution and the existence of local Hopf bifurcations are investigated. Also, it is shown that the appearance of the diffusion and homogeneous Neumann boundary conditions can lead to the appearance of codimension two Bagdanov-Takens bifurcation. Moreover, by applying the normal form theory and the center manifold reduction for partial differential equations (PDEs), the explicit algorithm determining the direction of Hopf bifurcations and the stability of bifurcating periodic solutions is given. Finally, numerical simulations supporting the theoretical analysis are also included. [ABSTRACT FROM AUTHOR]

This paper is concerned with the spreading speeds and traveling wave solutions of discrete time recursion systems, which describe the spatial propagation mode of two competitive invaders. We first establish the existence of traveling wave solutions when the wave speed is larger than a given threshold. Furthermore, we prove that the threshold is the spreading speed of one species while the spreading speed of the other species is distinctly slower compared to the case when the interspecific competition disappears. Our results also show that the interspecific competition does affect the spread of both species so that the eventual population densities at the coexistence domain are lower than the case when the competition vanishes. [ABSTRACT FROM AUTHOR]

Understanding processes underlying spatial distribution of tree species is fundamental to studying species coexistence and diversity. This study modeled point patterns of tree distribution, expressed by Cartesian coordinates of individual trees within a mapped forest stand, for the purpose of identifying processes that may generate spatial patterns of tree communities. We used four primary point pattern processes (homogeneous Poisson process, inhomogeneous Poisson process, homogeneous Thomas process, and inhomogeneous Thomas process) to model tree distribution in two stem-mapped forests in Taiwan, Republic of China. These four models simulate spatial processes of habitat association and seed dispersal, allowing us to evaluate the potential contribution of habitat heterogeneity and dispersal limitation to the formation of spatial patterns of tree species. The results showed that the inhomogeneous Thomas process was the best fit model and described most of the species studied, suggesting that spatial patterns of tree species might be formed by the joint effects of habitat associations and dispersal limitation. The homogeneous Thomas process that models the effect of dispersal limitation was the second best model. We also found that the best fit models could be predicted by species attributes, including species abundance and dispersal mode. The significant traits, however, differed between the two study plots and demonstrated site-specific patterns. This study indicated that the interactive operation of niche-based (habitat heterogeneity) and neutral-based (dispersal limitation) may be important in generating spatial patterns of tree species in forest communities. [ABSTRACT FROM AUTHOR]

To illustrate the interface of pharmacogenetics and therapeutic drug monitoring and to estimate target blood level for imatinib in the treatment of chronic myelogenous leukemia A literature review to provide the evidence and necessary data to support the case for the interface, and quantitative analysis of the data to estimate the target blood level for imatinib using receiver operating curve (ROC; signal detection theory) analysis. One study estimated the optimum target level of imatinib in chronic myelogenous leukaemia as 1002 ng/mL (1.70 µM) through ROC analysis. Using individual-patient level data reported in another study and the same methodology, we estimated the target level as 0.95 µM. This is consistent with the results of other observational studies where dose–response was not the primary research objective. The available evidence suggests considerable inter-individual variability in dose–blood level response. In addition to the pharmacogenetics of metabolic enzymes and transporters, genetic mutations in genes participating in the signalling pathways may also account for the wide inter-individual variability in dose–blood level and dose–clinical response relationships. A single-dose regimen for all pharmacogenetically eligible patients is not the optimum strategy for prescribing imatinib to patients with chronic myelogenous leukaemia. We suggest that therapeutic drug monitoring aimed at ensuring a trough target level of 1 µM would reduce the incidence of pseudo-resistance and hence personalize treatment and optimise response to imatinib. Persistent resistance can then be probed further for other causes. [ABSTRACT FROM AUTHOR]

We report on the growth of NiSi film on Si(001) substrate with an orientation of NiSi[200]//Si[001]. Polarized Raman spectroscopy was used to assign the symmetry of the NiSi Raman peaks. Raman peaks at 213 cm−1, 295 cm−1, and 367 cm−1 are assigned to be A g symmetry and peaks at 196 cm−1, and 254 cm−1 are B3 g symmetry. [ABSTRACT FROM AUTHOR]

Based upon comparisons between published experimental data and simulated results on the vertical sand flux distribution in the saltation layer, Shao’s similarity saltation model has been greatly improved by correcting the average vertical particle lift-off velocity and using a more suitable universal roughness length. By the improved model, the vertical sand flux profile over the bare, dry and loose uniform sandy surface, which is quite representative of real desert surfaces, can be reproduced very well. Meanwhile, the surface transport rate and the characteristic and average saltation heights have been simulated and analyzed in detail, disclosing their relationships with friction velocity, particle size and roughness length, and the possible underlying mechanisms. Besides, the average particle lift-off velocity and the average mean vertical aerodynamic action upon the ascending particle, which determine the saltation process, are explicitly expressed by parameters involved in the similarity model, and their relationships with friction velocity, particle size and roughness length are also described concisely. The corrected average particle lift-off velocity makes it possible to investigate the characteristic particle trajectory, whose initial velocity equals the average lift-off velocity, so as to estimate the average particle against surface impacting velocity and the average aerodynamic action upon the saltation process. [ABSTRACT FROM AUTHOR]

Abstract Purpose  To assess in vivo macrophage targeting potential of PEG-fMLF nanocarriers and to investigate their biodistribution, peritoneal macrophage uptake, and pharmacokinetics. Methods  Multiple copies of fMLF were conjugated to purchased and novel (branched, peptide-based) PEG nanocarriers. Peritoneal macrophage uptake was evaluated in mice 4 hours after IP administration of fluorescence-labeled PEG-fMLF nanocarriers. Pharmacokinetics and biodistribution were determined in rats after IV administration of tritiated PEG-fMLF nanocarriers. Results  Attachment of one, two, or four fMLF copies increased uptake in macrophages by 3.8-, 11.3-, and 23.6-fold compared to PEG without fMLF. Pharmacokinetic properties and tissue distribution also differed between nanocarriers with and without fMLF. Attachment of fMLF residues increased the t1/2 of PEG5K by threefold but decreased the t1/2 of PEG20K by 40%. Attachment of fMLF increased accumulation of nanocarriers into macrophages of liver, kidneys and spleen. However, on a molar basis, penetration was equivalent suggesting nanocarrier size and targeting moieties are important determinants. Conclusions  These results demonstrate the feasibility for targeting macrophages, a primary HIV reservoir site. However, these studies also suggest that balancing peripheral tissue penetration (a size-dependent phenomenon) versus target cell uptake specificity remains a challenge to overcome. [ABSTRACT FROM AUTHOR]

Objective: To measure renal blood flow (RBF) and renal function during recovery from experimental septic acute kidney injury (AKI).Design: Controlled experimental study.Subjects: Nine merino ewes.Setting: University physiology laboratory.Intervention: We recorded systemic and renal hemodynamics during a 96-h observation period (control) via implanted transit-time flow probes. We then compared this period with 96[Symbol: see text]h of septic AKI (48 h of Escherichia coli infusion) and subsequent recovery (48 h of observation after stopping E. coli).Measurements and Results: Compared with the control period, E. coli infusion induced hyperdynamic sepsis (increased cardiac output and decreased blood pressure) and septic AKI (serum creatinine 65.4 +/- 8.7 vs. 139.9 +/- 33.0 micromol/l; creatinine clearance 73.8 +/- 12.2 vs. 40.2 +/- 17.2 ml/min; p < 0.05) with a mortality of 22%. RBF increased (278.8 +/- 33.9 vs. 547.9 +/- 124.8 ml/min; p < 0.05) as did renal vascular conductance (RVC). During recovery, we observed a decrease in RVC and RBF with all values returning to control levels. Indices of tubular function [fractional excretion of sodium (FENa) and urea (FEUn) and urinary sodium concentration (UNa)], which had been affected by sepsis, returned to control values after 18 h of recovery, as did serum creatinine.Conclusions: Infusion of E. coli induced a hyperdynamic circulatory state with hyperemic AKI. Recovery was associated with relative renal vasoconstriction and reduction in RBF and RVC back to control levels. Indices of tubular function normalized more rapidly than changes in RBF. [ABSTRACT FROM AUTHOR]

Objective: To compare measurement of cardiac output (CO) by means of the FloTrac CO monitor with the pulmonary artery catheter (PAC).Design: Prospective observational study.Setting: Intensive care unit of a tertiary hospital.Patients: Six post-operative cardiac surgery patients with existing arterial cannulas and PACs.Interventions: Attachment of the FloTrac CO monitor and transducer to an existing arterial cannula. Simultaneous measurements of CO, indexed to body surface area (cardiac index, CI) by the FloTrac CO monitor and by either a bolus thermodilution or continuous CO PAC. Statistical analysis of observations.Measurements and Results: We performed CO measurements in six patients every 1-4 h after cardiac surgery. Comparison of all measurements showed a limited correlation for CI with the two devices (r (2)=0.1218, bias=0.21, 95% limits of agreement -0.81, 1.23). CI measurements obtained with the intermittent bolus PAC had better correlation with the FloTrac CI values (r (2) = 0.2693, bias=-0.0057, 95% limits of agreement -1.2042, 1.1929) than did those obtained with the continuous CO PAC (r (2)=0.0557, bias=0.2436, 95% limits of agreement -0.7350, 1.2222). When analysed according to heart rhythm, CI values measured during atrial pacing showed the best correlation (r (2)=0.377, bias=-0.0244, 95% limits of agreement -0.5226, 0.5714).Conclusions: CO measurements obtained using the FloTrac CO monitor show a limited correlation with those acquired using the PAC, relatively wide limits of agreement but no clear bias. Further evaluation is required before this device can be recommended for use in the clinical setting. [ABSTRACT FROM AUTHOR]

Let $${\Bbb T}$$ be a time scale such that 0, T ∈ $${\Bbb T}$$ . By means of the Schauder fixed point theorem and analysis method, we establish some existence criteria for positive solutions of the m–point boundary value problem on time scales where a ∈ C ld ((0, T), [0,∞)), f ∈ C ld ([0,∞) × [0,∞), [0,∞)), β, γ ∈ [0,∞), ξ i ∈ (0, ρ( T)), b, a i ∈ (0,∞) (for i = 1, . . . , m− 2) are given constants satisfying some suitable hypotheses. We show that this problem has at least one positive solution for sufficiently small b > 0 and no solution for sufficiently large b. Our results are new even for the corresponding differential equation ( $${\Bbb T}$$ = ℝ) and difference equation ( $${\Bbb T}$$ = ℤ). [ABSTRACT FROM AUTHOR]

Objective: To study the effect of resuscitation with normal saline on vital organ blood flow and renal function in sepsis. Design and setting: Randomized controlled cross-over animal study in the animal laboratory of university physiology institute. Subjects: Six merino cross-ewes. Interventions: Chronic implantation of flow probes around aorta, coronary, renal and mesenteric arteries. Intravenous administration of live Escherichia coli. Random allocation to normal saline resuscitation (20 ml/kg over 15 min) or observation (control) for 210 min. Continuous measurement of central haemodynamics, organ blood flow and renal function. Results: Live E. coli induced hyperdynamic sepsis with oliguria (28.3 ± 12.6 to 16.7 ± 11.9 ml/30min) and reduced creatinine clearance (87.9 ± 24.5 to 44.3 ± 34.5ml/min). During this septic state mesenteric, coronary and renal blood flow increased. During the first hour (early effect) after saline resuscitation, central venous pressure, cardiac output, stroke volume, coronary blood flow, mesenteric blood flow, urine output and creatinine clearance increased, but there was no change in renal blood flow. In the following 2 h these increments were significantly attenuated, but urine output and creatinine clearance remained greater than controls; renal blood flow decreased slightly and the fractional excretion of sodium increased significantly. Conclusion: In hyperdynamic sepsis resuscitation with normal saline increases central venous pressure, cardiac output, mesenteric blood flow, urine output, creatinine clearance, and fractional excretion of sodium despite a lack of effect on renal blood flow. These effects, however, are transient. [ABSTRACT FROM AUTHOR]

One of the most difficult tasks in the evaluation of a medicine is whether it causes a particular rare and unusual (idiosyncratic) adverse effect. Such causality assessments are sometimes done by drug de-challenge and re-challenge. When the adverse effect is potentially serious, there is clearly an important decision to be made as to whether the re-challenge is justifiable and hence ethical. The recent controversy about the potential cardiotoxicity of fexofenadine, the fatalities associated with penicillin re-challenge and the fatalities associated with abacavir re-challenge highlight some of the potential serious risks of drug re-challenge. The associated important ethical issues are discussed. In particular, there is the need to ensure respect for the patient and to consider the scientific and social value of the re-challenge. A framework for evaluating and assessing the appropriateness of a particular drug re-challenge is proposed in the light of recent as well as long-standing discussions of drug re-challenge, patient informed consent and the ethics of human experimentation, in general. It is suggested that a drug re-challenge should be approached with the same rigour and standards of documentation as are currently required of clinical trials. Given the potential conflicts of interest inherent with any drug study, it is argued that the safeguards, as may be provided by scrutiny by an ethics committee, are necessary for a drug re-challenge. For the investigator contemplating the conduct of a drug re-challenge we would recommend the following: a careful risk-benefit assessment as part of the decision-making process; careful scientific preparation, including appropriate expert support and emergency back-up facilities, if re-challenge is deemed necessary; the writing of a detailed protocol for independent approval and for safeguarding all concerned; and meticulous record keeping. [ABSTRACT FROM AUTHOR]

Objective: To examine the relative cost effectiveness of topical calcipotriol and short-contact dithranol in the treatment of mild to moderate plaque psoriasis.Design and Setting: This was a modelling study from the perspective of the UK National Health Service as payer.Methods: The interventions were compared using 2 decision-analytic models: one using a short term horizon (12 weeks) and the other using a longer term horizon (up to 1 year). Clinical success of treatment and relapse rates were obtained from the results of randomised controlled trials.Main Outcome Measures and Results: The outcome measure used was the degree of improvement in psoriasis as judged by the patient. In the short term comparison, calcipotriol was the most effective treatment (60.8% success), but it was also the most expensive (96.03 Pounds; 2000 values). The incremental cost per success was 577.50 Pounds using a 12-week course of calcipotriol compared with short-contact dithranol. Over the long term horizon, first-line treatment with calcipotriol still had the highest expected cost per successful treatment (164.91 Pounds), but the incremental cost using this strategy was 38.66 Pounds compared with short-contact dithranol. In terms of cost per successful day's treatment (i.e. the cost for a day in which the patient reported a marked improvement or cleared lesions), the cost of each additional successful day's treatment was 19.93 Pounds when using calcipotriol as first-line treatment rather than short-contact dithranol.Conclusion: The combination of differences in drug acquisition costs and relapse rates can lead to large differences in the comparative cost effectiveness of topical treatments for plaque psoriasis. From the perspective of the prescriber, the results of this analysis suggest that selecting short-contact dithranol as first-line treatment was the most cost-effective strategy. [ABSTRACT FROM AUTHOR]

In recent years, the use of alternative therapies has become widespread. In particular, there has been a resurgence in the public's demand for herbal remedies, despite a lack of high-quality evidence to support the use of many of them. Given the increasing pressures to control healthcare spending in most countries, it is not surprising that attention is being focused on the cost effectiveness of herbal remedies. We address the question of whether there is sufficient information to enable the assessment of the cost effectiveness of herbal remedies. In so doing, we discuss the current state of play with several of the more high-profile alternative herbal remedies [Chinese medicinal herbs for atopic eczema, evening primrose oil, ginkgo biloba, hypericum (St John's wort)] and some which have made the transition from being alternative to being orthodox remedies. We use historical context to discuss, on the one hand, the increasing commodification of herbal remedies and on the other, the trend towards greater regulatory control and licensing of alternative herbal remedies. We argue that unless great care is exercised, these changes are not necessarily in the best interests of patients. In order to identify cost-effective care, we need reliable information about the costs as well as the efficacy and safety of the treatments being assessed. For most alternative therapies, such data are not available. We believe that studies to gather such data are long overdue. Whilst we argue strongly in favour of control of some herbal remedies, we urge caution with the trend towards licensing of all herbal remedies. We argue that the licensing of those herbal remedies with equivocal benefits and few risks, as evidenced by a long history of safe use, increases barriers to entry and increases societal healthcare costs. [ABSTRACT FROM AUTHOR]