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Early detection of infected asymptomatic plants could prevent the dissemination of tomato bacterial canker throughout the crop and, thus, reduce associated economic losses. Reflectance spectroscopy has been proposed for the detection of diseases in plants, mainly caused by foliar fungal pathogens. In contrast, bacterial canker is a vascular disease that does not produce visible foliar symptoms until it is too late to avoid contagion to other plants. The effects of the disease on the conductivity of the xylem have an impact on the water content of the leaves; initially, a subtle effect that cannot be assessed with the naked eye but can be evaluated by reflectance spectroscopy. The objective of this work was to identify indices, based on the reflectance spectral signature of the plants, for the detection of tomato plants affected by bacterial canker prior to the appearance of symptoms. To verify that the proposed methodology is applicable to a broad range of tomato genotypes, two experiments were carried out with different tomato cultivars grown in pots and another on the ground in a greenhouse. Plants were inoculated with the pathogenic bacteria and the reflectance spectrum of the apical leaflet of two leaves per plant were obtained before symptoms expression; several spectral indices were calculated from the reflectance spectra. Three indices, of the shortwave-infrared zone, allowed the detection of bacterial canker inoculated plants in a fast and non-destructive way, up to one week before symptoms were visible: Normalized Difference Water Index (NDWI), Simple Ratio of Water Index (SRWI) and Water Index 1 180 (WI1180). Our research demonstrates, for the first time, the usefulness of spectral indices sensitive to water content for the identification of diseased plants. These indices arise as a promising tool for the early detection of vascular plant diseases, that could be integrated into sustainable management plans.

Albizia, a diverse tree genus, occupies monsoonal warm, humid rain forests in tropical and subtropical regions. We recovered a well-preserved compound fossil leaf and two fossil fruits of Albizia (Fabaceae) from the latest Neogene (Rajdanda Formation: Pliocene) sediments of Jharkhand of Chotanagpur Plateau, eastern India. On the basis of the architectural features of the fossil leaf, a new species is established as A. mahuadanrensis Hazra, Hazra and Khan, n. sp., characterised by a bipinnate, compound leaf having a rachis bearing opposite, asymmetrically ovate to sub-rhomboid leaflets, pulvinus on leaflet petiolule and brochiodromous secondary veins. Based on both morphological and anatomical characters of the fossil fruits, A. palaeoprocera Hazra, Hazra and Khan, n. sp. is erected, characterised by flattened to broadly linear shaped, wingless fruits; ovate-elliptic shaped seed chambers having ellipsoidal seeds in one series; irregularly polygonal to rectangular epidermal cells with oblique end walls and randomly oriented, scattered, paracytic stomata. Analysis of Albizia fossil occurrences indicates that the legume taxon was common in Neogene forests of India and elsewhere. The present-day distribution of the closely affiliated modern species of the fossil taxa indicates a warm and humid tropical environment during the time of deposition. We also review the biogeographic history of Albizia in India and other Asian countries.

A 69-year-old man with mediastinal radiation history underwent balloon valvuloplasty before transcatheter aortic valve replacement, which caused aortic leaflet rupture leading to unstable severe aortic regurgitation and subsequent left main ostial obstruction. A balloon-expanding valve was implanted to capture the ruptured leaflet and a left main stent was placed. (Level of Difficulty: Advanced.), Central Illustration

Background Tricuspid valve regurgitation (TR) is a risk factor for morbidity and mortality in children with hypoplastic left heart syndrome (HLHS). Surgical tricuspid valve (TV) repair is common, but durable repair remains challenging. The aim of this study was to examine mechanisms of TR requiring surgery, features associated with unsuccessful repair, and TV changes after surgical repair. Methods Thirty-six patients with HLHS requiring TV repair (TVR) and 36 matched control subjects with HLHS were assessed using two-dimensional and three-dimensional echocardiography. Using three-dimensional echocardiography, TV coordinates from the annulus, leaflet, and ventricle were used to measure annular, leaflet, prolapse, and tethering values and anterior papillary muscle angle. TR grade and ventricular size, function, and shape were assessed using two-dimensional echocardiography. Results Patients requiring TVR had greater total leaflet prolapse, larger TV annular and leaflet areas, and flatter annuli, with no difference in tethering, coaptation index, or anterior papillary muscle angle. In patients with HLHS, successful TVR at follow-up (58%) was associated with preoperative total leaflet prolapse (especially posterior). Unsuccessful repair was associated with preoperative tethering of the septal leaflet. TVR in patients with HLHS caused a reduction of total annular and leaflet size and reduced prolapse and tethering of the posterior leaflet but did not affect anterior leaflet prolapse or septal leaflet tethering. Conclusions Features associated with TVR include a flattened and dilated TV annulus with leaflet prolapse. The additional presence of a tethered septal leaflet before TVR is associated with significant postoperative TR. Current surgical techniques, predominantly posterior annuloplasty and commissuroplasty, adequately address annular size and posterior leaflet pathology, but not septal leaflet tethering. Individualized and innovative surgical techniques are vital to improve surgical repair success.

Sciodaphyllum montanum Idárraga, Jiménez-Mont. & Lowry and S. undulatum Jiménez-Mont., Idárraga & Lowry (Araliaceae) from the northern region of the Central and Western Cordilleras of the Andes in Colombia are described and illustrated. Sciodaphyllum montanum differs from other members of the genus mainly by a bulging disc up to 1.1 mm in height and a 3- to 4-carpellate ovary, and S. undulatum is distinguished by its undulate leaflet margin and the conspicuous scarlike amorphous lenticel 4.9–11 mm in diameter located abaxially on the base of the petiole. Notes are provided on possible taxonomic affinities of each species, as well as on their ecology and geographic distribution. Extinction risk assessments are given following the IUCN Red List categories and criteria, which indicate that both S. montanum and S. undulatum are Near Threatened (NT).

We propose a simple mechanism for the self-replication of protocells. Our main hypothesis is that the amphiphilic molecules composing the membrane bilayer are synthesized inside the protocell through exothermic chemical reactions. The slow increase of the inner temperature forces the hottest molecules to move from the inner leaflet to the outer leaflet of the bilayer. Because of this outward translocation flow, the outer leaflet grows faster than the inner leaflet. This differential growth increases the mean curvature and amplifies any local shrinking of the protocell until it splits in two. The proposed model, based on mere laws of physics, is a step in the study of the origin of life, as well as a clue for a better understanding of cell proliferation in cancer.

OBJECTIVES We have previously shown in experimental settings that a leaflet foldoplasty device reduces redundant leaflet area to re-establish mitral valve (MV) coaptation. The current study investigates the in vivo device retention and functional durability following foldoplasty. METHODS The prototype is of superelastic nitinol formed into a 3-dimensional shape. It is unfolded to engage a specified area of leaflet tissue and then folded to exclude this tissue from the coaptation surface. Design modifications were made and tested in benchtop studies to determine the optimal design for durable retention within the leaflet. To evaluate in vivo performance, posterior leaflet chordae were severed in Yorkshire pigs to produce complete posterior leaflet prolapse and severe mitral regurgitation. Design modifications were then used for MV repair. Five animals that underwent repair using the optimal design were observed for 2 weeks postoperative to evaluate the functional result and implant retention. RESULTS Device position and orientation were maintained at 2 weeks while preserving the functional MV repair in all 5 animals. Coaptation height was 5.5 ± 1.5 mm, which was not significantly different from a baseline of 4.9 ± 0.8 mm. The degree of leaflet excursion was 41.0 ± 16.0 compared to a baseline of 58.7 ± 27.5. CONCLUSIONS Device foldoplasty is a new concept for MV repair based on the reduction of redundant leaflet tissue area. This study demonstrates the feasibility of safe maintenance of this repair without early dislodgement or embolization.

— A new species of the genus Senna from the Atlantic Forest of Paraíba State, Brazil, is described and illustrated based on a field collection, traditional taxonomic methodologies, and the analysis of Senna collections at RB and the main herbaria in northeastern Brazil. Morphologically, Senna pluribracteata is related to a group of four species of Senna sect. Chamaefistula ser. Bacillares: S. macranthera, S. pinheiroi, S. rizzinii, and S. rugosa, although S. pluribracteata has a set of distinctive anatomical characters that differentiate it: two extrafloral nectaries between leaflets in the rachis; large and conspicuous elliptic bracts 7.0‐9.0 mm long along the inflorescence peduncle; the epidermis on the abaxial surface is conspicuously and compactly papillose; the rounded leaflet margins have palisade parenchyma near the apex; the mesophyll is dorsiventral with a single layer of palisade parenchyma, with isodiametric cells occupying approximately 60% of that structure; the petiole has a somewhat pentagonal shape and is planar adaxially; the rachis is obdeltoid and planar adaxially. Morphological and leaf anatomical descriptions, and a key to identifying the seven species of Senna ser. Bacillares found in Paraíba State are provided. The morphological and anatomical affinities of S. pluribracteata and its allied taxa are discussed.

This paper is an investigation into how the anatomy changes within a leaflet and between the leaflets of a single leaf blade of Butia. Four species of Butia were studied: Butia paraguayensis, B. eriospatha, B. yatay and B. odorata. Changes in the anatomical characters are important because some have been used in keys to help separate the species. Recently, anatomical mid-rib characters were used in a key to separate species of Butia. We found that characters, such as abaxially projected or rounded mid-rib fibrous ring or number and arrangement of accessory bundles, do change within a single leaflet or between the leaflets of a single leaf blade. Growing conditions and leaf developmental maturity are also important factors that influence leaflet anatomy and may cause one to be misled in an identification key based on anatomical characters. We re-emphasize the importance of always sampling from the same part of the leaf, to have a broader sampling, be attentive to the environmental condition and health of the plant from which you are sampling and to consider population differences.

Small leaflets make mitral valve repair procedures challenging. Our double-leaflet technique creates a new autologous pericardial leaflet attached to the papillary muscle, annuloplasty ring, and neighboring scallops above the small or tethered posterior leaflet. This simple additional technique provides deep coaptation after mitral valve repair for both degenerative and functional mitral regurgitation with the small or tethered posterior leaflet.

Angiosperm leaves show extensive shape diversity and are broadly divided into two forms; simple leaves with intact lamina and compound leaves with lamina dissected into leaflets. The mechanistic basis of margin dissection and leaflet initiation has been inferred primarily by analysing compound-leaf architecture, and thus whether the intact lamina of simple leaves has the potential to initiate leaflets upon endogenous gene inactivation remains unclear. Here, we show that the CINCINNATA-like TEOSINTE BRANCHED1, CYCLOIDEA, PROLIFERATING CELL FACTORS (CIN-TCP) transcription factors activate the class II KNOTTED1-LIKE (KNOX-II) genes and the CIN-TCP and KNOX-II proteins together redundantly suppress leaflet initiation in simple leaves. Simultaneous downregulation of CIN-TCP and KNOX-II in Arabidopsis leads to the reactivation of the stemness genes KNOX-I and CUPSHAPED COTYLEDON (CUC) and triggers ectopic organogenesis, eventually converting the simple lamina to a super-compound form that appears to initiate leaflets indefinitely. Thus, a conserved developmental mechanism promotes simple leaf architecture in which CIN-TCP-KNOX-II forms a strong differentiation module that suppresses the KNOX-I-CUC network and leaflet initiation.

Obesity is excessive body fat condition due to differences in energy consumption and expenditure. In Indonesia, the prevalence of obese women >18 years old is 32.9%. Interventions are performed with control eating and increased physical activity through an educational approach. A Leaflet is a print media containing some information, while my weight loss diet application is used by people that want to lose weight. Therefore, this study aims to determine the effect of nutritional education with leaflet and my weight loss diet application on nutritional status changes in obesity. True experimental design was used with pre-post test on female students divided into two groups in Universitas Brawijaya (n= 44) and selected by purposive sampling. Also, Independent-Samples T-Test and Mann Whitney analysis were conducted. The results showed a body mass index decrease in both media and no significant change related to BMI (p = 0.733). However, the decrease was more shown on the leaflet, where the body fat percentage had a significant change (p = 0.000). Hence, intervention using the leaflet is more effective on nutritional status changes related with BMI and body fat percentage in obese students.

Background Bicuspid aortic valves (BAV) and related aortopathy remain an intriguing topic. Not all BAVs get diseased and around 40% would develop aortic dilatation in their lifetime. If haemodynamic theory is to be believed, then leaflet fusion pattern should have an impact. This study sought to compare the association of aortic morphologies and rate of growth in a set of 102 BAV acropathies operated at a single centre, based on the fusion patterns. Methods Data on aortic valve replacements over a 10-year period was analysed from a prospectively maintained database. Of the 198 BAV undergoing surgery, 102 had aortic dilatation above 40 mm on echocardiogram. These underwent computed tomography (CT) aortograms and were followed up as a part of a database. The impact of leaflet fusion patterns on aortic dilatation pattern and rate was analysed. Results Of the 102, two patients had type 0 pathology and one had left-noncoronary (LN) leaflet fusion. Seventy-four (74) had type 1A or left-right (RL) fusion and 25 had type 1B right-noncoronary (RN) fusion. RL fusion had more males, were taller, bigger and had more proportion of aortic stenosis (AS). Aortic diameters, angles and growth rates at root, ascending/descending aorta and arch were not different. Regression analyses for size or growth did not show any significant impact of fusion pattern. Conclusions Left-right fusion pattern comprised three-quarters of BAV in this cohort and these patients were bigger, taller and had a greater proportion of males with increased rate of aortic stenosis. Despite these differences, there was no significant impact of fusion pattern on aortic size or rate of growth.

We explored multiple experimental treatments for regenerating tissue-cultured shoots of tetraploid Robinia pseudoacacia L., and assessed the most suitable combination of treatments for the development of a highly efficient regeneration system. Leaflets of tissue-cultured shoots were used as explants to study the effects of four different treatments on leaf regeneration capacity. Treatments included leaflet position on donor leaves, light conditions during culturing, the orientation of leaves on the growth medium, and the number of cut wounds per leaf. After determining an appropriate stem explant culture period, we assessed the influence of four treatments on regenerative capacity. The 35-d-old leaf explants produced the largest amount of callus tissue, while the highest average callus growth index was observed on the leaves cultured for an additional 30 d. Each leaf produced an average of five adventitious buds. The greatest numbers of buds and callus tissues were observed in the leaves collected from the uppermost position on the shoot, treated with six cut wounds per leaf, and grown under illuminated conditions.

Measuring biomass and leaf area using non-destructive methods is of great interest to avoid plant degradation. These data are necessary for biomass allocation and estimation of carbon distribution in trees using functional and structural growth models such as GREENLAB. Organ biomass and leaf area are important parameters in plant physiology and production. They are used in structural and functional plant models to simulate tree architecture but are difficult to determine rapidly. Using stem length and internode diameter and leaf length and width to estimate them is a rapid, non-destructive field approach. We used the method on Khaya senegalensis, Pterocarpus erinaceus and Parkia biglobosa in Cote d'Ivoire. Internodes and leaves of the three species were sampled in 2019 and 2020 on three categories of axis in the architecture of individuals of different ages to maximize size variability. All statistical relationships found in the linear, logarithmic, polynomial and power models used to estimate the dry biomass of organs and leaf area were significant in all three species (P = 0.0001). The best models were obtained with the logarithmic transformation of the data. Three equation (linear, power and polynomial) were sufficient to estimate internode dry biomass (IDM), leaf dry biomass (LDM) and leaf area (LA) from the dimensions of the internodes (Volume: VL) and leaves (rachis length: RCL, number of primary leaflets: NLt, length: LLtL and width: LLtW of the largest primary leaflet in Khaya senegalensis and Pterocarpus erinaceus, then number of secondary leaflets: NSeLt, length: LSeLtL and width: LSeLtW of the largest secondary leaflet in Parkia biglobosa). In the field, the scientist will therefore make a choice according to his convenience among these proposed models. The best relationships between the measured organ dimensions and estimated parameters were defined by the following equations: IDM = 0.45*VL + 0.02, LDM = 1.07*NLt*LLtL*LLtW-2.74 and LA = 0.83*NLt*LLtL*LLtW or LA = 0.08*[NLt*LLtL*LLtW]2 + 1.13*[NLt*LLtL*LLtW]-0.27 for Khaya senegalensis; IDM = 1.15*VL0.26, LDM = 0.71*RCL*LLtL*LLtW-1.64 and LA = 0.74*NLt*LtL*LtW + 0.15 or LA = 0.03*[NLt*LLtL*LLtW]2 + 0.65*[NLt*LLtL*LLtW] + 0.23 for Pterocarpus erinaceus then IDM = 1.45*VL0.39, LDM = 0.23*[NSeLt*LSeLtL*LSeLtW*NLt]2–0.4*[NSeLt*LSeLtL*LSeLtW*NLt]-0.11 and LA = 1.81*[NSeLt*LSeLtL*LSeLtW*NLt]0.65 for Parkia biglobosa. This method can be applied to estimate the organ biomass and leaf area of species of the same family as the target species in an agroforestry system.

Objective Bioprosthetic heart valves (BHVs) are commonly used in surgical and percutaneous valve replacement. The durability of percutaneous valve replacement is unknown, but surgical valves have been shown to require reintervention after 10 to 15 years. Further, smaller-diameter surgical BHVs generally experience higher rates of prosthesis–patient mismatch, which leads to higher rates of failure. Bioprosthetic aortic valves can flutter in systole, and fluttering is associated with fatigue and failure in flexible structures. The determinants of flutter in BHVs have not been well characterized, despite their potential to influence durability. Methods We use an experimental pulse duplicator and a computational fluid-structure interaction model of this system to study the role of device geometry on BHV dynamics. The experimental system mimics physiological conditions, and the computational model enables precise control of leaflet biomechanics and flow conditions to isolate the effects of variations in BHV geometry on leaflet dynamics. Results Both experimental and computational models demonstrate that smaller-diameter BHVs yield markedly higher leaflet fluttering frequencies across a range of conditions. The computational model also predicts that fluttering frequency is directly related to leaflet thickness. A scaling model is introduced that rationalizes these findings. Conclusions We systematically characterize the influence of BHV diameter and leaflet thickness on fluttering dynamics. Although this study does not determine how flutter influences device durability, increased flutter in smaller-diameter BHVs may explain how prosthesis–patient mismatch could induce BHV leaflet fatigue and failure. Ultimately, understanding the effects of device geometry on leaflet kinematics may lead to more durable valve replacements.

Cowpea bruchid is a major constraint to cowpea production. Easy identification of resistant/tolerant accessions to bruchid infestation has been a major challenge in bruchid resistant breeding programmes. Hence, the study was aimed to evaluate variations in some morphological characters between some bruchid resistant/tolerant and susceptible cowpea accessions, correlating them with their bruchid tolerance status in the hope of identifying a pointer character(s) that can facilitate easy identification of bruchid tolerant among cowpea germplasm. Sixty accessions were collected and evaluated for bruchid tolerance. Accessions were then grouped into bruchid susceptible and bruchid tolerant. These accessions were planted in Randomized Complete Block Design with ten replicates. Morphological differences between groups were evaluated accordingly. Of the sixty accessions evaluated, fifty-two were susceptible while eight were bruchid tolerant. No qualitative differences were observed between bruchid susceptible and tolerant groups, however significant differences were observed in quantitative characters which include terminal leaflet length, terminal leaflet/width ratio, leaf petiole length, terminal leaflet petiole length (TLPL), leaf petiole length, pod length (PDL), pod width, total number of pods per plant, seed length (SDL), seed width (SDW), seed thickness (SDTK) and 100 seed weight (100SDW). Bruchid tolerance was significantly positively correlated with seed characters which include, SDL (r = 0.798, p < 0.01); SDW (r = 0.798, p < 0.01); SDTK (r = 0.758, p < 0.01);100SDW (0.830, p < 0.01) and significantly negatively correlated with TLPL and PDL (p < 0.05). These characters can provide easy identification of bruchid tolerant among cowpea germplasm, hence requires further investigations. Keywords: Cowpea, Vigna unguiculata, Bruchid, Callosobruchus maculatus, Morphology

A field traial allowed in completely randomized design with three replications were conducted in the research farm of the agricultural research station of Etay Al-Baroud (old land) and the research farm of the Faculty of Agriculture, Damanhur University, in El-Bostan region, El-Beheira Governorate (newly reclaimed lands) during 2018 and 2019 seasons to evaluate the performance of twelve new genotypes of soybean compared with the three commercial varieties Giza 111, Giza 22 and Crawford. The resistance of genotypes to cotton leaf worm was estimated in the laboratory by raising a fourth instar larvae of cotton leaf worm and leaving them for feeding on the middle leaflet of the third upper trifoliate leaf of the plant for 24 hours, after that the areas that the insect fed on were measured as a percentage of the total area of the leaf (leaf area consumed). The resistance to cotton leaf worm in the field was estimated by vision according to the Smith and Brim 1979 method (defoliation %). The results confirmed that mean square due to genotypes, locations and genotypes x location were highly significant for all studied traits except the locations mean square for number of hairs under binocular field area and branches number /plant in the first season and genotypes x location mean square of number of hairs under binocular field area, branches number /plant, maturity date and 100-seed weight in both seasons as well as number of pods/plant in the second season. All tested genotypes significantly differ in their performances in all studied traits across the two locations and the four genotypes Line 3, Line 105, Line 127 and Line 129 seemed to excellent genotypes for yield and resistance to cotton leaf worm across the two locations. The consumed leaf area caused by cotton leaf worm and oil percentage negatively associated with pubescence density while seed yield positively associated with pubescence density. Seed yield and oil percentage negatively associated with the defoliation value. In general, it can be said that the four soybean genotypes, Line 3, Line 105, Line 127 and Line 129 are promising genotypes that could be sowing in newly reclaimed lands to expand soybean cultivation in Egypt.

This study was conducted during 2017 and 2018 seasons on Barhee date palm cv. (Phoenix dactylifera L.) at the age of 18 years, grown in three regions of Upper Egypt i.e Matana, Luxor Governorate; Kom- Ombo and Toshka, Aswan Governorate to evaluate its vegetative properties as well as physical properties and determination chemical composition of fruits. The obtained results revealed that, there were significant differences between the vegetative characteristics of date palm Barhee cv. because of different weather conditions of locations conducted study. The palms grown in Matana region recorded the largest values of the palm girth, number of leaves, length of the leaf and leaflet, leaflet area, spines number and area, while the lowest values of these parameters were obtained the palms grown in Toshka region. There are significant differences between the yield components because of growing Barhee in the three regions of Upper Egypt. There were significant differences of both physical and chemical fruits properties harvested from different regions of study. Barhee in Kom-Omboregion recorded the largest values of fruit length, fruit shape index, fruit weight, specific gravity of fruit, weight and percentage of flesh in the two study seasons. The highest values of TSS percentages, total and reducing sugars, Nitrogen, Phosphorus and Potassium content and lowest tannins content. The highest values of non-reducing sugars, the highest moisture content, and the lowest acidity were obtained in the case of Barhee in Toshka region. Generally, the productivity and quality of Barhee palm could be arranged discerningly as follows: Kom-Ombo, Matana and Toshka.

Previous research has reported that many high-school and undergraduate students have difficulty explaining the relationship between polarity and electronegativity even though they may be familiar with the concept of polarity. This study aims to address these misconceptions using a leaflet and assess its effectiveness using questionnaires and concept testing. A simple, colorful printable leaflet was produced and distributed to students in Indonesia. The Leaflet on Electronegativity (LoEN) provided students with an overview of the theoretical basis of the concepts and guidance on applying these principles. The leaflet format is cheap and easy to mass-produce, which is an important factor given the limited access to other types of appropriate learning resources in Indonesia. The leaflet formed the basis of a classroom discussion activity. Visualization is known to play an important role in constructing students' conceptual understanding, so the leaflet made extensive use of diagrams to explain relevant concepts. The leaflet was printed in full color to make it visually appealing and facilitate student learning. Students were tested before and after learning with the LoEN. A Paired-sample t-test using SPSS is used to compare the pretest and posttest scores to measure the effectivity of the LoEN.A statistically significant improvement in scores (p = 0.000) was achieved, which indicates that using the LoEN in the classroom helps students understand the topic. Also, students' positive responses signify that the LoEN provides an engaging way to learn the concepts.

The present study evaluates the development of visible injury related to phytotoxic ozone dose (PODy) in native tropical species Astronium graveolens Jacq. (Anacardiaceae) and validates the symptoms using structural markers attributed to oxidative burst and hypersensitive responses. Increasing POD0 was associated with increasing O3 visible injury using different metrics as the incidence (INC = number of injured plants/total number of plants × 100), severity (SF = number of injured leaves/total number of leaves on injured plant × 100), and severity leaflet (SFL = number of injured leaflets/total number leaflets injured plant × 100). The effective dose (ED), which represents the POD0 dose responsible for inducing 20 (ED20), 50 (ED50), or 80% (ED80) of visible injury, were used to demonstrate that for this species, the response is similar even when the plants are exposed to diverse climate environments. Further investigation of the INC and SF index may help in long-term forest monitoring sites dedicated to O3 assessment in forests, while the SFL index seems to be an excellent indicator to be used in the short term to investigate the effects of O3.

Objective In chronic aortic insufficiency (AI), the method and degree of annular downsizing required to achieve durable coaptation in aortic valve repair (AVr) remains poorly defined. This study evaluated the relationship between leaflet size and annular diameter to predict adequate annular sizing in remodeling AVr. Methods Under regulatory supervision, 74 patients with chronic tri-leaflet AI underwent AVr using ring annuloplasty and leaflet reconstruction. Fifty-four (73%) had ascending aortic ( n = 25) and/or root ( n = 29) aneurysms, and aortic grafts were sized 5 to 7 mm larger than the rings. Intraoperatively, leaflet free-edge length (FEL) was measured with special ball sizers positioned in the coronary sinus, and “normal” annular diameter was predicted from the validated formula: Required “normal” diameter = FEL/1.5. “Normal” annular diameters predicted from FEL were compared with pathologic diameters measured intraoperatively with Hegar dilators, and both were correlated with gender, age, and BSA. Results Average age was 62.1 ± 13.3 years (mean ± SD), 73% (54/74) were male, and 96% (71/74) had moderate-to-severe AI. All patients had annular dilatation, with a pathologic diameter 26.6 ± 2.3 mm before repair, and a predicted “normal” diameter of 21.7 ± 1.7 mm ( P < 0.001). Both predicted and pathologic annular diameters were larger in men ( P < 0.001), but no relationship existed with age. BSA correlated with both predicted and pathologic diameters, although variability was large. Conclusions Based on a simple validated method to predict “normal” annular diameter, all patients with chronic AI have some degree of annular dilatation. This finding implies that most AVr should include annuloplasty, with adequate and precise annular reduction based on leaflet size.

In this study, we use for the first time the electropenetrography (EPG) technique to characterize and describe the feeding activities of Collaria scenica (Stål) adults and their respective waveforms on wheat, Triticum aestivum L. plants. It comprised of four waveforms, two related to non-feeding (Np and R) and two with feeding activities (CR and I). The Np wave represents the insect resting or walking on the plant surface (75% of the recording time). R wave was associated to sensory evaluation of leaf surface with the tip of the labium (labial dabbing activity-ca. 1% of the recording time). Feeding activities were of relative short duration; cell rupture waveform (CR-ca. 49 min-ca. 15% of the recording time) was highly irregular due to constant movement of the stylets internally in the plant tissue. The waveform I (ca. 28 min-ca. 9% of the recording time) showed stereotypical and repetitive pattern and represents ingestion of the cell contents previously degraded via cell-rupturing activities. The damage caused by C. scenica in wheat leaflets is a result of cell-rupturing activities, generated by action of digestive enzymes plus mechanical action of serrated mandibular stylets. This results in whitish streaks, dots, or spots on the leaflet of wheat plants which cause significant damage and eventually plants' death.

In most legumes, two typical features found in leaves are diverse compound forms and the pulvinus-driven nyctinastic movement. Many genes have been identified for leaf-shape determination, but the underlying nature of leaf movement as well as its association with the compound form remains largely unknown. Using forward-genetic screening and whole-genome resequencing, we found that two allelic mutants of Medicago truncatula with unclosed leaflets at night were impaired in MtDWFARF4A (MtDWF4A), a gene encoding a cytochrome P450 protein orthologous to Arabidopsis DWARF4. The mtdwf4a mutant also had a mild brassinosteroid (BR)-deficient phenotype bearing pulvini without significant deficiency in organ identity. Both mtdwf4a and dwf4 could be fully rescued by MtDWF4A, and mtdwf4a could close their leaflets at night after the application of exogenous 24-epi-BL. Surgical experiments and genetic analysis of double mutants revealed that the failure to exhibit leaf movement in mtdwf4a is a consequence of the physical obstruction of the overlapping leaflet laminae, suggesting a proper geometry of leaflets is important for their movement in M. truncatula. These observations provide a novel insight into the nyctinastic movement of compound leaves, shedding light on the importance of open space for organ movements in plants.

The production of superhydrophobic coatings inspired by the surface of plant leaves is a challenging goal. Such coatings hold a bright technological future in niche markets of the aeronautical, space, naval, building, automobile, and biomedical sectors. This work is focused on the adaxial (top) and abaxial (bottom) surfaces of the leaflet of the Ceratonia silique L. (carob), a high-commercial-value Mediterranean tree cultivated in many regions of the world. The adaxial and abaxial surfaces feature hydrophobic and superhydrophobic behaviors, respectively. Their chemical composition is very simple: monopalmitin ester and palmitic acid are protuberant in the epicuticular and intracuticular wax layers of the adaxial surface, respectively, whereas 1-octacosanol dominates in the abaxial wax layers. In both surfaces, epicuticular wax is organized along a randomly oriented and intricate network of nanometer-thick and micrometer-long plates, whose density and degree of interconnection are significantly higher in the abaxial surface. The measured tilting angles for the abaxial surface (12-70°) reveal unusual variable density and water adhesion of the nanostructured plate-based texture. Optical measurements demonstrate that light reflectance/absorbance of the glaucous abaxial surface is significantly higher/lower than that of the nonglaucous adaxial surface. In both surfaces, diffuse reflectance is dominant, and the absorbance is weakly dependent on the light incidence angle. We show that the highly dense nanostructured platelike texture of the epicuticular abaxial layer of the C. siliqua leaflet works as a sophisticated light and water management system: it reflects solar radiation diffusely to lower the surface temperature, and it has superhydrophobic character to keep the surface dry. Such attributes enable efficient gas exchange (photosynthesis and respiration), transpiration, and evaporation. To mimic for the first time the abaxial surface, a templation approach was adopted using poly(dimethylsiloxane) (PDMS)/poly(methylphenylsiloxane) (PMPS) positive/negative replicas and a soft polymer/siloxane negative replica produced by the sol-gel process. Because high topographical variations of the biotemplate and wax adhesion to the biohybrid film affected the replication quality, the reproduction of the wax texture via the synthesis of 1-octacosanol-grafted siloxane-based hybrid materials is proposed as a suitable route to duplicate the abaxial surface with high fidelity. The natural chemical/physical strategy adopted by the C. siliqua leaflet to face the harsh Mediterranean climate is a powerful source of bioinspiration for the development of diffuse reflecting and superhydrophobic material systems with foreseen applications as dual-functional antiglare and water-repelling coatings.

Bignonieae is the largest tribe of Bignoniaceae, with 21 genera and 393 species of lianas and shrubs that are 1–3-foliolate with the terminal leaflet modified as tendrils. We examined the micromorphologies of the epidermis from the leaflet blade of 13 species of Bignonieae belonging to Amphilophium, Anemopaegma, Bignonia, Cuspidaria, Dolichandra, Fridericia, Pyrostegia, Tanaecium, and Xylophragma, from Pico do Jabre, Paraíba, Brazil. These are lianas except for Tanaecium parviflorum (shrub). We sought to identify the epidermal leaflet parameters to support their taxonomy, subject to great similarities between their vegetative characters, mainly in species of the same genus and related genera. Analyses were performed using light and scanning electron microscopy, and showed five types of epicuticular waxes, four cuticle types, three epidermal cell anticlinal wall types, and nonglandular and glandular trichomes. Hypostomatic leaves showed 10 different types of stomata, with stomatal indices from 6.21% (Bignonia ramentacea) to 23.52% (Tanaecium parviflorum), and stomatal densities from 76 stomata/mm2 (Pyrostegia venusta) to 752.9 stomata/mm2 (T. parviflorum). The presence of raphides in Amphilophium crucigerum and styloids in Fridericia pubescens constitute the first records for these genera. Epidermal micromorphology provided a set of distinctive characters with which to separate these species, representing an additional tool to support their taxonomies, as well as that of tribe Bignonieae.

This article examines the establishment of private periodical press of the Taurida Governorate in the late XIX century. The object of this research is the first private newspaper – “Crimean Leaflet”. The author explores the socioeconomic processes and censorship conditions, which affected the emergence of the Crimean private periodicals. An overview is given to the historiography and sources used in this work. The first part of the article studies the sociopolitical and cultural-historical prerequisites for the emergence of mass media in the governorate. The second part examines the process of opening and operation of the newspaper, its outline, biography of the publisher, as well as composition of the editorial board. The third part reveals the subject matter of the published materials and the peculiarities of interaction of the newspaper with the provincial administration and censorship authorities. The author also analyzes the reasons why the newspaper was shut down. In conclusion, the author reviews the role of the newspaper in formation of private provincial press, and its impact upon public relations in the Taurida Governorate. The scientific novelty consists in introduction into the scientific discourse of previously unstudied archival materials, as the historiography virtually had no records on the newspaper and the personality of the publisher. This work contributes to studying the development of private press in the Taurida Governorate, as well as reveals certain details of state policy with regards to provincial press in the late XIX century.

Enlargement of the mitral valve (MV) has gained attention as a compensatory mechanism for functional mitral regurgitation (FMR). We aimed to determine if MV leaflet area is associated with MV coaptation-zone area and identify the clinical factors associated with MV leaflet size and coaptation-zone area in patients with normal left ventricle (LV) systolic function and size using real-time 3D echocardiography (RT3DE).We performed RT3DE in 135 patients with normal LV size and ejection fraction. MV leaflet and coaptation-zone areas were measured using custom 3D software. The clinical factors associated with MV leaflet and coaptation-zone areas were evaluated using univariate and multivariate linear regression analyses.There was a significant relationship between MV leaflet and coaptation-zone areas (r = 0.499, P < 0.001). MV leaflet area was strongly associated with body surface area (BSA) (r = 0.905, P < 0.001) rather than LV size and age. MV leaflet area/BSA was independently associated with male gender (P = 0.002), lower diastolic blood pressure (P = 0.042), and LV end-diastolic volume (LVEDV) index (P = 0.048); MV coaptation-zone area/BSA was independently associated with lower LVEDV index (P = 0.01).In patients with normal LV systolic function and size, MV leaflet size has a significant impact on competent MV coaptation. MV leaflet area might be intrinsically determined by body size rather than age and LV size, and the MV leaflet area/BSA is relatively constant. On the other hand, some clinical factors might also influence MV leaflet and coaptation-zone area.

A study was carried out on biophysical characters of coconut and oil palm located in different villages of West and East Godavari districts to see their effect on infestation of rugose spiraling whitefly, Aleurodicus rugioperculatus Martin. The biophysical leaf characters viz ., leaflet colour, number of leaflets/leaf, leaflet length (cm), leaflet width (cm), leaflet thickness (mm) and trichomes/cm2, etc ., were studied. It was observed that among all the biophysical characters only two characters viz ., length of the leaflet in both coconut (0.923) and oil palm (0.952) exhibited significant positive correlation with pest infestation and thickness of the leaflet in coconut (−0.870) and oil palm (−0.892) showed significant negative correlation whereas leaflet width in case of oil palm (0.978) was found significantly positively correlated with the rugose whitefly infestation.

The transbilayer distribution of cholesterol (CHL) in complex asymmetric lipid membranes remains controversial, with contrasting investigations suggesting that there is more CHL either in the exoplasmic, outer leaflet (OL) or the cytoplasmic, inner leaflet (IL) depending on cell type or model, membrane composition, and method of investigation. Here, we launch systematic coarse-grained molecular dynamics simulations to investigate the impact of the sphingomyelin (SM) acyl chain length upon CHL distribution in asymmetric lipid membrane mixtures which account for the variation of the most abundant headgroups and acyl chain unsaturation in the two membrane leaflets. We find that there is always more CHL in the OL, but longer chain SM depletes more CHL from the IL than short chain SM in simple membrane mixtures containing SM and 16 : 0, 18 : 1 phospholipids. The difference between longer and shorter chain SM is neutralised in a more complex asymmetric membrane, where there are more saturated tails in the outer leaflet. We propose that interdigitation of long-chain SM into the opposing IL pushes cytoplasmic CHL towards the OL, but higher chain saturation of the outer leaflet compensates for the effect of SM chain length. This journal is

The variability in leaf form in nature is immense. Leaf patterning occurs by differential growth, taking place during a limited window of morphogenetic activity at the leaf marginal meristem. While many regulators have been implicated in the designation of the morphogenetic window and in leaf patterning, how these effectors interact to generate a particular form is still not well understood. We investigated the interaction among different effectors of tomato (Solanum lycopersicum) compound-leaf development, using genetic and molecular analyses. Mutations in the tomato auxin response factor SlARF5/SlMP, which normally promotes leaflet formation, suppressed the increased leaf complexity of mutants with extended morphogenetic window. Impaired activity of the NAC/CUC transcription factor GOBLET (GOB), which specifies leaflet boundaries, also reduced leaf complexity in these backgrounds. Analysis of genetic interactions showed that the patterning factors SlMP, GOB and the MYB transcription factor LYRATE (LYR) coordinately regulate leaf patterning by modulating in parallel different aspects of leaflet formation and shaping. This work places an array of developmental regulators in a morphogenetic context. It reveals how organ-level differentiation rate and local growth are coordinated to sculpture an organ. These concepts are applicable to the coordination of pattering and differentiation in other species and developmental processes.

In this work, we describe Dialium heterophyllum, a new species for the largest genus in the diverse and morphologically unique legume subfamily Dialioideae. Dialium, with 32 species, has its highest diversity in tropical Africa and Asia, with four species accepted until now in the Neotropics. The fifth species described here reinforces the idea that a large portion of the Neotropical diversity, notably in the Amazon, is still unknown. Dialium heterophyllum is restricted to the south of the Amazon Basin in Brazil and Bolivia, areas under intense anthropic pressure in recent years. Due to its floral morphology, the species appears to be closely related to the other Neotropical species of the genus, differing by its reduced leaf rachis with unifoliolate to trifoliolate leaves, generally opposed to sub-opposed leaflets, the terminal leaflet much longer than the lateral ones (when present) and than the leaf rachis. We provide illustrations, distribution maps, a conservation risk assessment and an identification key.

Cayratia s. l. is not a monophyletic genus and is now divided into four genera worldwide, with three genera (Cayratia s. s., Causonis and Pseudocayratia) occurring in China. Recent morphological and molecular analyses of the Cayratia-like species from Zhejiang, East China, revealed three new species. Causonis wentsiana sp. nov. differs from C. japonica in having multicellular-pilose branchlets, leaves, peduncles and petals, petals long-corniculate at the apex. Causonis montana sp. nov. differs from C. japonica in having thick, papery leaf blades, central leaflet with lateral veins 9–12 pairs, margin 12–22-toothed on each side, and seeds acutely rugate both adaxially and abaxially. Pseudocayratia orientalisinensis sp. nov. differs from P. speciosa in having non-branched stems, papery leaf blades with central leaflet broadly obovate-elliptic, broadly elliptic or rhombic-elliptic and short-acuminate to acute apices.

The aim of this research was to determine to blue melilot yield and quality properties sown at different rates of 5, 10, 15, 20, 25, 30, 35 1 and 40 on November 4, 2015, on November 7, 2016 and on October 30, 2017. Investigated properties showed significantly differences. The lowest number of branches per plant (1.47), main stem diameter (3.20 mm) and leaflet width (1.44 cm) values were measured from blue melilot genotype 'BG-4' with 40 kg ha-1 seeding rate. The maximum main stem diameter (4.96-5.04 mm) and leaflet length (4.50-4.88 cm) were found from 5 to 15 kg ha-1 seeding rates. Highest plant height (84.48 cm), number of branches per plant (4.27), leaf length (7.12 cm), main stem diameter (4.41 mm), leaf/stem ratio (0.82), leaflet length (4.38 cm) and width (2.22 cm) were observed for BG-3 blue melilot genotype compared to other genotypes. Increasing seed rates resulted with an increase in crude protein, fresh fodder and dry matter yields. However, increasing seed rates caused decrease in crude fiber, neutral detergent fiber, acid detergent fiber and acid detergent lignin contents. The K, Ca, P and Mg contents of blue melilot genotypes ranging from 2.40-2.55 %, 1.48-1.56 %, 0.60-0.68 % and 0.40-0.45 %, respectively. According to results, blue melilot can be sown at a seeding rate of 30 kg ha-1 similar regions.

Cell membranes are fluidic, and the fluidic properties give unique biological functions to the membranes. Here, we review the application of fluorescence lifetime correlation analyses to elucidate ...

The LAM1 transcription factor regulates expansion of primary leaflets in the compound leaves of tomato, and also affects floral organ development, fruit size, and initiation of secondary leaflets., Plant-specific WOX family transcription factors play important roles ranging from embryogenesis to lateral organ development. The WOX1 transcription factors, which belong to the modern clade of the WOX family, are known to regulate outgrowth of the leaf blade specifically in the mediolateral axis; however, the role of WOX1 in compound leaf development remains unknown. Phylogenetic analysis of the whole WOX family in tomato (Solanum lycopersicum) indicates that there are 10 members that represent the modern, intermediate, and ancient clades. Using phylogenetic analysis and a reverse genetic approach, in this study we identified SlLAM1 in the modern clade and examined its function and tissue-specific expression pattern. We found that knocking out SlLAM1 via CRISPR/Cas9-mediated genome editing led to narrow leaves and a reduced number of secondary leaflets. Overexpression of tomato SlLAM1 could rescue the defects of the tobacco lam1 mutant. Anatomical and transcriptomic analyses demonstrated that floral organ development, fruit size, secondary leaflet initiation, and leaf complexity were altered due to loss-of-function of SlLAM1. These findings demonstrate that tomato SlLAM1 plays an important role in the regulation of secondary leaflet initiation, in addition to its conserved function in blade expansion.

Two pot experiments were carried out at the Experimental Farm of the Agricultural Botany Department, Faculty of Agriculture, Al-Azhar University (Assiut branch), Assiut, Egypt, during two successive seasons of 2018 and 2019. The main aim of this study was to find out the effect of both of foliar application with some growth promoters (using nanotechnology) i.e., zinc, iron, copper oxide nanoparticles at 50, 100 and 150 mgl-1 of each and silica nanoparticles at 20, 40 and 60 mgl-1 as well as salinity stress level of irrigation water at 9000 mgl-1 individually and their interactions on growth, biochemical and anatomical characteristics of Moringa oliefera L. plant. The results showed that individually salinity stress level of irrigation water at 9000 mgl-1 decreased all studied vegetative growth parameters of moringa plant i.e., plant height (cm), stem diameter (cm), leaves number plant-1, leaf area plant-1 as well as root, stem and leaves dry weights plant-1 compared with the control. The same trend was obtained in photosynthetic pigments content (total chlorophyll) as well as the studied anatomical characteristics of root section (i.e., root diameter of V.C and length of xylem arch), stem section (i.e., stem diameter, O of V.C, length of V.B in the stem) and Leaf blade section (i.e., upper epidermis thickness, lower epidermis thickness and mesophyll tissue for leaflet) at 50 days of Moringa oliefera leaves compared with unstressed plant. On other hand, salinity stress level at 9000 mgl-1 resulted in increasing antioxidant activity as well as total phenolic contents at 60 days of Moringa oliefera leaves compared with unstressed plant. Data also indicated that the individually foliar application treatments with Zinc, Iron, Copper oxide nanoparticles at 50, 100, 150 of each and Silica at 20, 40, 60 mgl-1 nanoparticles increased studied vegetative growth as well as anatomical characteristics, chemical compositions, photosynthetic pigments (total chlorophyll), antioxidants activity and total phenolic contents of moringa plant compared with the control treatment. In this respect, Silica nanoparticles at 60 mgl-1 followed by zinc and iron oxide at 150 mgl-1 nanoparticles of each were the most effective treatments, respectively. Finally , Based on these results, it could be concluded that the foliar application with nanoparticles gave the highest Valois of morphological, chemical compositions and anatomical characteristics its that reduce the harmful effects of salinity stress of Moringa oliefera L. plant specially at silica 60 mgl-1,. Data recorded that this results using it under the same field conditions (Assiut governorate, Egypt).

Leaflet escape from mechanical heart valves is a rare but potentially fatal complication of prosthetic valve replacement. Historically, the incompetent valve is replaced emergently and the escaped leaflet is subsequently retrieved from its settlement in a distal vessel. If it is not retrieved, the fragment can increase the risk of infection, thrombosis, and migration. We report a case of a mechanical aortic valve leaflet that embolized during valve reoperation and caused occlusive aortic disease found 2 years later. This case emphasizes the importance of locating leaflet fragments after they are noticed missing.

Background: Flour albus causes discomfort so that it requires increased behavior in preventing fluorine albus. The behavior of preventing vaginal discharge in fertile age women is still a health problem that needs attention. The Health Promotion Model theory emphasizes the active role of fertile age women in regulating healthy living behavior which aims as the prevention of a disease including fluorine albus or vaginal discharge, one of which is health education through leaflet media (Rachmadianti, 2019). Purpose: to determine the effectiveness of the use of leaflet media on the prevention behavior of pathological leucorrhoea in fertile aged women at the Polindes, Kedaton Village, Kapas District, Bojonegoro Regency. Methods: The research design used in this study was a pre-experimental design with one group pretest-posttest design. The sample in this study were some of the women of fertile age at the Polindes Village of Kedaton, Kapas District, Bojonegoro Regency as many as 39. The data analysis technique used in this study was the Mc Nemar test statistic. Results: more than some respondents had positive behavior, namely as many as 20 (51.3%) before being given leaflet media, and more than some respondents had positive behavior, namely as many as 31 (79.5%) after being given leaflet media. The results of calculations by SPSS with the Mc Nemar test showed that the significance value obtained to analyze the effectiveness of leaflet media on pathological vaginal discharge prevention behavior in women of childbearing age was 0.003. With a significance level of 5%, 0.003

OBJECTIVES The Florida-sleeve is a valve-sparing technique that causes minimal interference to leaflet kinematics and aortic root dynamism. The aim of this in vitro study was to evaluate the effects of the Florida-sleeve and Yacoub techniques on aortic leaflet kinematics. METHODS Two groups of 6 whole porcine hearts were treated with either the Florida-sleeve technique or the Yacoub technique and tested in a pulsatile loop. Valve fluid dynamics, coronary flow analysis and valve echocardiograms were performed both before and after the procedures. RESULTS Both procedures showed no difference in rapid valve opening time as compared with their respective baseline values. The Florida-sleeve procedure showed a shorter slow closing time (192 ± 19 ms vs baseline 244 ± 14 ms, P = 0.016) and increased slow closing velocity (−1.5 ± 0.4 cm/s vs baseline −0.8 ± 0.4 cm/s, P = 0.038). In the rapid valve closing phase, the Yacoub procedure showed a trend towards slower closing valve velocity (−16 ± 9 cm/s vs baseline −25 ± 9 cm/s, P = 0.07). The Yacoub procedure showed larger leaflet displacement at the end of the slow valve closing time that was 2.0 ± 0.5 cm vs baseline 1.5 ± 0.3 cm, P = 0.044. When comparing the Florida-sleeve and Yacoub procedures, the former showed statistically significant shorter slow valve closing time (P = 0.017). CONCLUSIONS This study showed that the Florida-sleeve technique alters the slow closing phase of the aortic valve leaflet kinematics when compared with both the normal baseline and Yacoub procedure, while the latter showed a larger leaflet displacement before the rapid closing valve phase.

Tricuspid regurgitation (TR) is an uncommon and underdiagnosed complication of blunt chest trauma. Typical mechanisms include torn chordae, papillary muscle rupture, and radial leaflet tear. We describe an unusual case of traumatic TR due to circumferential avulsion of the anterior tricuspid leaflet from the tricuspid annulus and the crucial role of multimodality imaging in its diagnosis and treatment. (Level of Difficulty: Intermediate.), Graphical abstract

Transcatheter aortic valve replacement devices vary in leaflet material and in the height for which leaflets attach to the stented valve frame. Combinations of these features can influence leaflet dynamics, neo-sinus geometries, and fluid dynamics, thereby reducing or exacerbating the potential for blood flow stasis and leaflet thrombosis. To investigate these interconnected relationships, this study evaluated the effects of transcatheter valve leaflet type [porcine versus bovine pericardium] and the leaflet-stent attachment height (low, mid, and high) on flow stasis and potential for leaflet thrombosis. Transcatheter valve models were manufactured and tested within an aortic simulator under pulsatile left heart hemodynamic conditions. Transvalvular hemodynamics, leaflet kinematics, and flow structures were evaluated by direct measurement, high-speed imaging, and two differing techniques of particle image velocimetry. Transcatheter valves with porcine pericardial leaflets were observed to be less stiff, exhibit a lesser resistance to flow, were associated with reduced regions of neo-sinus flow stasis, and superior sinus washout times. More elevated attachments of the leaflets were associated with less neo-sinus flow stasis. These initial results and observations suggest combinations of leaflet type and stent attachment height may reduce transcatheter aortic valve flow stasis and the potential for leaflet thrombosis.

Valvular pathologies that induce deterioration in the aortic valve are a common cause of heart disease among aging populations. Although there are numerous available technologies to treat valvular conditions and replicate normal aortic function by replacing the diseased valve with a bioprosthetic implant, many of these devices face challenges in terms of long-term durability. One such phenomenon that may exacerbate valve deterioration and induce undesirable hemodynamic effects in the aorta is leaflet flutter, which is characterized by oscillatory motion in the biological tissues. While this behavior has been observed for thinner bioprosthetic valves, the specific underlying mechanics that lead to leaflet flutter have not previously been identified. This work proposes a computational approach to isolate the fundamental mechanics that induce leaflet flutter in thinner biological tissues during the cardiac cycle. The simulations in this work identify reduced flexural stiffness as the primary factor that contributes to increased leaflet flutter in thinner biological tissues, while decreased membrane stiffness and mass of the thinner tissues do not directly induce flutter in these valves. The results of this study provide an improved understanding of the mechanical tissue properties that contribute to flutter and offer significant insights into possible developments in the design of bioprosthetic tissues to account for and reduce the incidence of flutter.

Transcatheter aortic valve (TAV) leaflet thrombosis is a clinical risk with potentially fatal consequences. Studies have identified neo-sinus flow stasis as a cause of leaflet thrombosis. Flow stasis is influenced by the TAV leaflets, which affect the local fluid dynamics in the aortic sinus and neo-sinus. This study evaluated the effects of TAV leaflet features on the neo-sinus flow as a measure of leaflet thrombosis risk. Five TAVs of varied leaflet length and insertion height were tested in a simulator. Hydrodynamics and leaflet kinematics through en-phase imaging were quantified. Velocity fields were assessed using high-speed particle image velocimetry. Regions of flow stasis and particle residence times (PRTs) were quantified. TAVs with shorter leaflet length exhibited larger orifice areas and lower transvalvular pressure gradients. Shorter leaflet length and increased leaflet insertion TAVs additionally exhibited lower neo-sinus PRTs (0.44 ± 0.21 vs 2.83 ± 0.48 cycles, p

Compound leaves are composed of multiple separate blade units termed leaflets. In tomato (Solanum lycopersicum) compound leaves, auxin promotes both leaflet initiation and blade expansion. However, it is unclear how these two developmental processes interact. With highly variable complexity, tomato compound leaves provide an ideal system to address this question. In this study, we obtained and analyzed mutants of the WUSCHEL-RELATED HOMEOBOX (WOX) family gene SlLAM1 from tomato, whose orthologs in tobacco (Nicotiana sylvestris) and other species are indispensable for blade expansion. We show that SlLAM1 is expressed in the middle and marginal domains of leaves, and is required for blade expansion in leaflets. We demonstrate that sllam1 mutants cause a delay of leaflet initiation and slightly alter the arrangement of first-order leaflets, whereas the overall leaflet number is comparable to that of wild-type leaves. Analysis of the genetic interactions between SlLAM1 and key auxin signaling components revealed an epistatic effect of SlLAM1 in determining the final leaf form. Finally, we show that SlLAM1 is also required for floral organ growth and affects the fertility of gametophytes. Our data suggest that SlLAM1 promotes blade expansion in multiple leaf types, and leaflet initiation can be largely uncoupled from blade expansion during compound leaf morphogenesis.