Leaf Clover Research Articles

A Comprehensive Overview of the Ulianov Theory

BThis article provides a comprehensive overview of the Ulianov Theory (UT), a pioneering model formulated by Dr. Policarpo Yoshin Ulianov. The UT offers a revolutionary approach to understanding the universe, anchored in mathematical rigor and logical scrutiny. Central to its framework is a redefined conception of time, positing it as a digital and complex variable time dimension and aligning the notion of imaginary time, with six digital spatial dimensions (three normal space dimensions an three spatial wrapped dimensions) named as General Octo-Dimension Universe (GODU), that also can see like four five-dimensions subuniverses separate by walls of space and walls of time, an original idea proposed by Issac Asimov in 1966 to explain a ”four leaf clover universe” beginning for noting, with the antimatter universes going to the negative time direction (travel to the past before the Big Bang). The Ulianov theory present a 12 basic particles model (6 particles and 6 antiparticles, like the quarks) seems as elastic holes in walls of time and space. The connections between it proposes particles properties (mass and electric charge) are familiar within our observable universe. In challenging prevailing scientific paradigms, UT beckons the scientific community to reassess foundational beliefs. The UT is based on only two fundamental forces (gravitational and eletromagnetic), replacing the Nuclear Strong add Week Forces by an Gravitational Contact Force, that becomes in play only wen two masses becomes in contact (with a Planck distance between then). Additionally, the article delves into a novel String Theory model (when photons, protons electrons and neutrons are basically the same length string, but wrapped in distinct ways). The UT also presents the ”Small Bang” hypothesis, suggesting the universe’s genesis from a small and cold space bubble (only a Planck length of diameter), with antimatter micro black hole becomes supermassive antimatter black holes and generating matter and antimatter (in the same proportion), stolen energy by the cosmic inflation field. Within the UT’s purview, seminal equations from classical physics, Einstein’s theories of relativity, and quantum mechanics are eloquently derived.

Growth, Productivity, Yield Components and Seasonality of Different Genotypes of Forage Clover Lotus corniculatus L. under Varied Soil Moisture Contents.

This study aimed to evaluate the response to water deficit of different ecotypes and a variety of Lotus corniculatus on growth, productivity, and yield components, through seasonal times. A randomized block experimental design in a 2 × 5 factorial arrangement with three replicates was used. The first variation factor was soil moisture contents: field capacity (FC) was 26.5% ± 1.5, and water deficit (WD) was 85% of FC (22.5% ± 1.5); the second variation factor was the ecotypes identified with the codes 255301, 255305, 202700 and 226792 and of the variety Estanzuela Ganador. The best responses in plant cover and weight of accumulated fresh biomass were obtained in the ecotype 202700 under WD, with values of 1649.0 cm2 and 583.7 g plant-1, and 1661.2 cm2 and 740.1 g plant-1 in ecotype 255305 under FC. The leaf clover was the main component of yield during the summer and autumn seasons. Ecotype 226792 was tolerant to low temperatures during the winter season with better leaf development. Ecotype 202700 is the best option for forage clover production when water is limited, and ecotype 255305 when water is not resource-limited, but these preliminary conclusions need to be confirmed in field studies.

A “4 leaf clover aortic valve” – not as lucky as it sounds

A “4 leaf clover aortic valve” – not as lucky as it sounds

ANN-based estimation of MEMS diaphragm response: An application for three leaf clover diaphragm based Fabry-Perot interferometer

In this study, an artificial neural network (ANN) based model is developed for MEMS diaphragm analysis, which does not require difficult and time-consuming FEM processes. ANN-based estimator is generated for static pressure response (d) and dynamic pressure response (f) analysis of TLC (three leaf clover) diaphragms for Fabry-Perot interferometers as an example. TLC is one of the unsealed MEMS design diaphragms formed by three leaves of equal angles. The diaphragms used to train ANNs are designed with SOLIDWORKS and analyzed with ANSYS. A total of 1680 TLC diaphragms are simulated with eight diaphragm parameters (3 for SiO2 material, 4 for geometry, and 1 for pressure) to create a data pool for ANN’s training, validation, and testing processes. 80% of the data is used for training, 15% for validation, and the remaining for testing. Only four geometric parameters are used as input in the ANN estimator, and the material parameters are added to the model with an analytical multiplier. Thus, network models that estimate d and f values for all kinds of diaphragm materials are proposed, with a material-independently trained ANN structure. The performance of the ANN model is compared with the empirical equation suggested in the literature, and its superiority is demonstrated. In addition, the d and f parameters of TLC diaphragms designed with five different materials (Si, In2Se3, Ag, EPDM, Graphene) are estimated to be very close to the real ones. By using the proposed method, analyses of TLC diaphragms are quickly performed without the need for time-consuming and costly design and analysis programs.

First Description of the Mitogenome and Phylogeny of Culicinae Species from the Amazon Region.

The Culicidae family is distributed worldwide and comprises about 3587 species subdivided into the subfamilies Anophelinae and Culicinae. This is the first description of complete mitochondrial DNA sequences from Aedes fluviatilis, Aedeomyia squamipennis, Coquillettidia nigricans, Psorophora albipes, and Psorophora ferox. The mitogenomes showed an average length of 15,046 pb and 78.02% AT content, comprising 37 functional subunits (13 protein coding genes, 22 tRNAs, and two rRNAs). The most common start codons were ATT/ATG, and TAA was the stop codon for all PCGs. The tRNAs had the typical leaf clover structure, except tRNASer1. Phylogeny was inferred by analyzing the 13 PCGs concatenated nucleotide sequences of 48 mitogenomes. Maximum likelihood and Bayesian inference analysis placed Ps. albipes and Ps. ferox in the Janthinosoma group, like the accepted classification of Psorophora genus. Ae. fluviatilis was placed in the Aedini tribe, but was revealed to be more related to the Haemagogus genus, a result that may have been hampered by the poor sampling of Aedes sequences. Cq. nigricans clustered with Cq. chrysonotum, both related to Mansonia. Ae. squamipennis was placed as the most external lineage of the Culicinae subfamily. The yielded topology supports the concept of monophyly of all groups and ratifies the current taxonomic classification.

Vertex Magic Labeling On V_4 for Cartesian product of two cycles

Let be an abelian group under multiplication. Let . Then the vertex magic labeling on is induced as such that where the product is taken over all edges of incident at is constant. A graph is said to be - magic if it admits a vertex magic labeling on . In this paper, we prove that , , Generalized fish graph, Double cone graph and four Leaf Clover graph are all -magic graphs.

Mitochondrial genome sequencing and phylogeny of Haemagogus albomaculatus, Haemagogus leucocelaenus, Haemagogus spegazzinii, and Haemagogus tropicalis (Diptera: Culicidae)

The genus Haemagogus (Diptera: Culicidae) comprises species of great epidemiological relevance, involved in transmission cycles of the Yellow fever virus and other arboviruses in South America. So far, only Haemagogus janthinomys has complete mitochondrial sequences available. Given the unavailability of information related to aspects of the evolutionary biology and molecular taxonomy of this genus, we report here, the first sequencing of the mitogenomes of Haemagogus albomaculatus, Haemagogus leucocelaenus, Haemagogus spegazzinii, and Haemagogus tropicalis. The mitogenomes showed an average length of 15,038 bp, average AT content of 79.3%, positive AT-skews, negative GC-skews, and comprised 37 functional subunits (13 PCGs, 22 tRNA, and 02 rRNA). The PCGs showed ATN as start codon, TAA as stop codon, and signs of purifying selection. The tRNAs had the typical leaf clover structure, except tRNASer1. Phylogenetic analyzes of Bayesian inference and Maximum Likelihood, based on concatenated sequences from all 13 PCGs, produced identical topologies and strongly supported the monophyletic relationship between the Haemagogus and Conopostegus subgenera, and corroborated with the known taxonomic classification of the evaluated taxa, based on external morphological aspects. The information produced on the mitogenomes of the Haemagogus species evaluated here may be useful in carrying out future taxonomic and evolutionary studies of the genus.

The feeding habits of Wiseana (Lepidoptera: Hepialidae) species on a traditional Māori food crop

ABSTRACTFor Māori the kūmara symbolises the extensive voyages from the ancestral home of Hawaiki to Aotearoa New Zealand and the ingenuity needed to adapt growing practices for a tropical crop to the climate of New Zealand. From the thirteenth century, kūmara cultivation occurred along the coastlines in the warmer regions of New Zealand where its associated pests were controlled by traditional methods. In 1952, an observation was made indicating that Wiseana, an endemic genera of ghost moths, possibly fed on kūmara. The current study investigates the feeding habits and preferences of laboratory-reared Wiseana copularis and W. cervinata larvae for kūmara through no-choice and choice test bioassays. Kūmara tuber provided the largest mean weight gain for the two Wiseana species with a 122% increase by week 6 compared to white clover foliage. The mean weight gain of larvae fed with kūmara leaf, kūmara stem or white clover were not significantly different. All kūmara and white clover options were equally selected by larvae within the two-choice tests, therefore there was no differential preference for the kūmara plant material. This data indicates that the polyphagous herbivore larvae of Wiseana spp. may have fed on kūmara in traditional kūmara gardens, supporting the early published record. Further research is needed to determine if Wiseana larvae are affecting kūmara production today.Ki te Māori ko te kūmara e hua ai ngā hekenga maha ā ngā tīpuna mai i a Hawaiki ki Aotearoa, me ā rātou mōhiotanga ki te whakatipu i te kūmara ki te āhuarangi mātoke o Aotearoa. Nō te rautau tekau mā toru i whakatipu ai ngā kumara ki ngā takutai o Aotearoa ā, i āraia atu ngā mate, ngā kīrearea mā te whakaritenga tūturu. I te tau 1952 nō te tirohanga mai o te porina (Wiseana) kainga pea e te pūrehurehu taketake i ngā kūmara. Ko te rangahau o naianei ko ngā whiringa me ngā hiahia o te kai ā ngā torongū porina i whakatipu ai i roto i te taiwhanga pūtaiao ki roto i te whakamātau kore-kōwhiri, te whakamātau kōwhiri rānei. Ko te kōpura i whakaputa ai i te taumaha nui ake i te 122% i te taumaha o te korowa i te wiki tuaono. Kāhore he taumaha tino rerekē mō te whā me te kakau o te tipu ki te korowa. Kei roto i te kōwhiri whakamatau, ko ngā kūmara katoa me ngā korowa i kōwhiringia ōritengia ai e te huhu, nā reira kaore kau he mea rerekē mo te hiahiatanga o te tipu kūmara. I te mutunga, ē whakaatu ana te raraunga nei, kainga pea e te kaitipu huhu i ngā kūmara o ngā māra tūturu, hei tautoko hoki tēnei i ngā tuhinga o mua. Ma te rangahau anō ka kitengia mehemea ka pāngatia tonutia e te huhu (Wiseana) i te whakanaonga o ngā kūmara o naianei.

Válvula aórtica cuadricúspide, un hallazgo poco frecuente

The quadricuspid aortic valve has a low incidence. Some studies say that this incidence is about 0,008% of general population. It is like to find a four leaf clover and phisically both are similar. Is it not weird?

Effect of different clear corneal incision sites on surgery efficacy and anterior segment parameters in patients undergoing phacoemulsification

To determine the safe distance range of clear corneal incision (CCI) from the corneal limbus and how different CCI sites affect surgery efficacy and anterior segment parameters in patients undergoing phacoemulsification. This retrospective case-control study was conducted in 44 patients (44 eyes) undergoing phacoemulsification and IOL implantation. The patients were divided into two groups with CCI distances ranging from 1 mm to 1.5 mm (group A, n= 22) and from 0.5 mm to 1.0 mm (group B, n= 22). The visual acuity, surgically induced astigmatism (SIA), corneal aberration, and anterior segment parameters were analyzed. Compared with the preoperative data, all the patients showed significant improvements in the postoperative uncorrected visual acuity (UCVA), best corrected visual acuity (BCVA), anterior chamber depth (ACD), and anterior chamber angle (ACA) after the surgery (P < 0.05). No significant differences were found between the two groups in postoperative UCVA, BCVA, SIA, total corneal aberration RMS, lower- and higher-order aberration RMS, spherical aberration (Z40), horizontal three leaf clover (Z33), vertical three leaf clover(Z3-3), horizontal coma(Z31), vertical coma(Z3-1), ACD, ACA, anterior chamber volume, or central corneal thickness (P>0.05). Phacoemulsification is an effective therapy for cataract with a CCI distance range either of 1-1.5 mm or 0.5-1.0 mm. These two CCI distance ranges produce no significant differences in the visual quality following phacoemulsification, indicating that a CCI distance range of 0.5-1.5 mm can be safe for phacoemulsification.

A novel approach based on simulation of tunable MEMS diaphragm for extrinsic Fabry–Perot sensors

A new tunable structure with a Three Leaf Clover (TLC) geometry has been proposed for use in diaphragm-based acoustic pressure sensors. The sensitivity and frequency response of this new structure, which will be an alternative to conventional circular diaphragms, was accomplished using Finite Element Method (FEM) and numerical analysis techniques. As a result of the analysis, sensitivity and frequency response approaches were obtained for the tunable-TLC structure. These approaches provide researchers to design diaphragms more convenient. Conventional circular diaphragms can be easily converted to TLC diaphragms by means of micro-electromechanical systems (MEMS) thus can be tuned up to 5 times for sensitivity and up to 1/3 times the fundamental frequency without altering the thickness and radius of the diaphragm. Obtained approach expressions were compared with FEM results for practical design purposes in a wide range of tunable parameters, and the average errors were below 2.5% for the sensitivity and below 0.5% for the fundamental frequency response, respectively.

Rylene annulated phthalocyanine: a fully conjugated block for the construction of a supramolecular two-dimensional framework.

A rylene annulated phthalocyanine (ZnPcPDI4) was designed and synthesized. Single-crystal X-ray diffraction analyses unambiguously confirmed the giant molecule quasi-planar "four leaf clover" skeleton with a 27 Å diameter and a two-dimensional cage-like supramolecular structure. The fully conjugated characteristics endowed it with significant Q-band red-shifts to the near-infrared region of 785 nm, and a largely degenerated LUMO level.

NUMERICAL AND MECHANICAL ANALYSES OF A 3D-PRINTED TITANIUM TRABECULAR DENTAL IMPLANT

The main focus of this paper is to investigate and describe a novel biomaterial structure. The trabecular structure has only recently been recognized as a viable alternative for prostheses and implants and seems to have very promising biocompatibility and mechanical properties. The 3D printing technique was used to create test specimens. These specimens were then tested by nanoindentation and tensile and compression tests. A numerical model was created and curve-fitted to represent the mechanical behavior of the trabecular structure. A significant reduction in the values of Young’s modulus <em>E</em> was observed. The values of <em>E</em> for conventional implant materials are approximately 110–120GPa and the trabecular structure reached a value just below 1GPa. The next effort will be to apply the model onto a real implant. It is the “four leaf clover” implant variant by authors F. Denk Jr., A. Jíra and F. Denk Sr.

Influence of phacoemulsification combined with limbal relaxing incisions for preoperative astigmatism on corneal high-order aberrations

Background phacoemulsification combined with limbal relaxing incision (LRI) is reported to be effective for the management of coexisting cataract astigmatism, but the influence of after phacoemulsification with LRI on corneal high-order aberration is still rarely reported. Objective This study was to evaluate the effect of cataract surgery with LRI for preoperative astigmatism or on corneal high-order aberration. Methods A self-controlled serial cases observational study was designed.A total of 35 cataractous eyes of 35 patients with astigmatism ≥1.0 D before cataract surgery were enrolled in Tianjin Medical University Eye Hospital from August 2014 to April 2015 under the informed consent of patients.LRIs were performed on the eyes during the phacoemulsification and IOL implantation.The uncorrected visual acuity (UCVA), BCVA and optometry were recorded before operation and 1 day, 1 week, 1 month, 3 months after operation.Pentacam was employed to measure the maximal and minimal diopters, astigmatism and high-order aberrations within 3 mm of the anterior corneal surface at above-mentioned time points.All the results were compared among different time points.The optometry outcomes and the anterior corneal surface astigmatism change were analyzed using vector analysis method. Results The UCVA was 0.34±0.22, 0.38±0.25, 0.43±0.27, 0.42±0.28 in 1 day, 1 week, 1 month and 3 months after operation, which was significantly higher than 0.08±0.09 before operation; and the BCVA was 0.54±0.27, 0.64±0.29, 0.67±0.29, 0.71±0.32 in 1 day, 1 week, 1 month and 3 months after operation, showing a significant increase in comparison with 0.22±0.51 before operation(F=54.457, P=0.000; F=62.653, P=0.000). The refractive cylindrical error and corneal astigmatism were significantly decreased after operation in comparison with before operation(F=31.061, P=0.000; F=113.043, P=0.000). High order aberrations (HOA) at postoperative 1 day, 1 week, 1 month, 3 months were all higher than those in preoperation (F=11.189, P=0.000) under the 4 mm pupil diameter.Compared with preoperation, the vertical coma, secondary vertical coma and three leaf clover were significantly increased(all at P 0.05) under the 6 mm pupil diameter. Conclusions Phacoemulsification combined with LRI can reduce the corneal astigmatism effectively and steadily, and the increase of corneal aberrations does not affect visual acuity. Key words: Cataract/surgery; Cataract/complication; Astigmatism/surgery; High order aberration; Limbal relaxing incision

Complete mitochondrial genome sequence of <i>Daphnia magna</i> (Crustacea: Cladocera) from Huaihe in China

利用Long-PCR及普通PCR技术,结合引物步移法测序,经拼接、组装后获得中国淮河大型溞(Daphnia magna)线粒体基因组全序列,并对其基因组成、结构特点等进行初步分析. 大型溞线粒体基因组全长为14948 bp, A、T、G、C各碱基含量分别为32.37%、34.73%、15.58%、17.31%,表现出明显的AT偏倚. 13个蛋白质编码基因、22个tRNA基因、2个rRNA基因和1个D-loop区(控制区)的排列方式与典型的节肢动物线粒体基因组的排列方式略有不同. 除COI基因以CTG、ATP8基因以GTG、ND3基因以ATC以及ND6基因以ATT为起始密码子以外,其余9个蛋白质编码基因均以ATG作为起始密码子;9个蛋白质编码基因具有典型的完全终止子TAG或TAA,COI、COII、ND4和ND5等基因采用不完全终止密码子T. 基因组包含9个基因间隔区,共81 bp,长度1~62 bp;13个基因重叠区,共77 bp,重叠碱基数在1~27 bp之间,最大重叠在16S rRNA和tRNA^Val基因之间. 在预测的22个tRNA基因的二级结构中,发现只有tRNA^Ser1基因未能形成完整的二级结构,其他21个基因均可形成典型的三叶草结构. 16S rRNA和12S rRNA基因长度分别为1373 bp和752 bp,D-loop区全长289 bp. 本研究结果为探讨大型溞在溞属中的系统学地位及其与其他种间的系统发生关系等问题提供了数据资源.;The complete sequence of mitochondrial genome of Daphnia magna was determined using long PCR, normal PCR and primers walking approaches. The results showed that the entire mitochondrial genome of Daphnia magna is 14948 bp in size, in which the content of A, T, G, C is 32.37%, 34.73%, 15.58%, 17.31%, respectively. The mitochondrial genome organization and gene order of Daphnia magna were consistent with that of Arthropod, which contains 13 protein-coding genes (PCGs), 22 tRNA genes, 2 ribosomal RNA genes (large and small ribosomal RNAs), and a control region. Except for COI gene using CTG, ATP8 with GTG, and ND3 with ATC, and ND6 with ATT as the initiation codon, and other 9 PCGs of the mtDNA in Daphnia magna started with the typical ATG codon. TAG and TAA were used in 9 PCGs as usual termination codons, except for COI, COII,ND4 and ND5 genes with incomplete termination codon (T). There are 9 intergenic spacer sequencer totaling 81 bp (1-62 bp for each sequence) and 13 overlapping sequences totaling 77 bp (1-27 bp for each sequence), scattered throughout the genome, respectively, and the largest overlap (27 bp) region is located between 16S rRNA and tRNA^Val genes. The secondary structures of 22 tRNAs were predicted and it was found that tRNA^Ser1 failed to form a complete secondary structure, others have typical leaf clover secondary structures. The length of 16S rRNA, 12S rRNA and D-loop were 1373 bp, 752 bp and 289 bp, respectively. The results of this study provide some useful molecular data to clarify the systematical status of Daphnia, as well as its phylogenetic relationships with other species.

Combining garden therapy and supported employment - a method for preparing women on long-term sick leave for working life.

Women are overrepresented among the group people suffering from long-term illness. In addition to their illness, suffering long-term sick leave leads to economical restraints as well social distress. There are gaps in our understanding of the challenges these women face. There is also lack of knowledge about how these challenges can be effectively addressed in rehabilitation. This deficiency is problematic from an ethical, justice and a caring perspective. In this study, changes in health-related quality of life (HRQoL) among women on long-term sick leave were investigated during and after participating in a rehabilitation programme combining two validated methods, Garden Therapy and Supported Employment (SE). The study also discusses difficulties in realising research related to vulnerable under-privileged people. From a population of 329 women who had reported their interest to participate, 245 were randomised to the programme. Of these 144 accepted participation in the research project and of these 123 women accepted to answer the SF-36 questionnaire. The participants were between 21 and 62years with poor physical and mental health. They had received public financial support from <1year to >10years. The SF-36 measurement was carried out at baseline, after completion of Garden Therapy and after completion of SE. The results are based on data of respondents who participated at all the three occasions (n=52). When comparing HRQoL baseline with the following occasions, the participants' General Health (GH), Vitality (VT), Social Functioning (SF) and mental health had improved significantly. The Four Leaf Clover (FLC) programme could be an appropriate method for reducing socially induced suffering. However, to conduct intervention studies where vulnerable persons are involved, it is off vital importance to consider whether the participants have the strength to complete the intervention.

Semi fractal three leaf clover-shaped CPW antenna for triple band operation

This article presents a unique and compact coplanar waveguide CPW antenna that exhibits triband operation with circular polarization. The single antenna was designed to operate simultaneously in the following bands: WiMAX 3.3-3.6 GHz, wireless local area network WLAN 5.15-5.825 GHz, ITS 5.795-6.400 GHz, and ITU-R 7.725-8.5 GHz. The realization of the triband antenna was achieved by using two semi fractal ring patches resembling the shape of a three leaf clover, and by introducing a pair of symmetrical L-shaped slits in its ground plane. The antenna's physical parameters were investigated to fully understand their affect on the antenna's performance. The salient parameters obtained from this analysis enabled the optimization of the antenna's overall characteristics. The design concept was confirmed by fabricating the antenna prototype and measuring its characteristics. The proposed antenna has dimensions of 20 × 20 × 1 mm3. Measured results show the antenna exhibits circular polarization in WiMAX and ITU-R bands, and linear polarization in the WLAN band. The antenna radiates omnidirectionally in the H-plane, and approximately bidirectionally in the E-plane. In addition, the antenna presents stable gain over the triband. © 2014 Wiley Periodicals, Inc. Int J RF and Microwave CAE 25:413-418, 2015.

Особенности восстановления архитектоники кости при многооскольчатых переломах проксимального отдела плеча

Questions of treatment of seldom met pathology – multisplintered changes of a head of a humeral bone with shift of an articulate surface to 180º in literature practically don&amp;#180;t reflected. The author’s experience consisted of treatment of 9 patients by such pathology in the period from 1999 to 2011. The endoprosthesis was not applied. The author’s technique of recovery of very tectonics of a bone at reconstruction of a head of a shoulder was developed. This technique consists in osteosynthesis fragments using modular designs of the basic T- and L-shaped plates with reconstructive plate. The developed technique of surgical intervention allows to restore architectonics of the proximal humerus when multisplintered fractures with the turn of the articular surface of the head arm 180. Implementation of operative intervention on the restoration of the architectonics of the bone with a complex multisplintered the turn of using plates, which are collected in the form of a module directly in the operating wound after reposition fragments are technically more doable than osteosynthesis cumbersome implants type «leaf clover» and Pelon&amp;#180;s plate. From 9 patients with difficult multisplintered changes, three patients were operated by the offered technique with use of modular designs. When performing operations surrounding tissues were injured minimum. Duration of operation was reduced from 1,5-2h. at the using bulky plates till, 1h. at the using modular designs. A smaller amount of metal in subacromial space allowed to reduce the severity of collision syndrome.

Harmonic structure of generic Kerr orbits

Generic Kerr orbits exhibit intricate three-dimensional motion. We offer a classification scheme for these intricate orbits in terms of periodic orbits. The crucial insight is that for a given effective angular momentum $L$ and angle of inclination $\ensuremath{\iota}$, there exists a discrete set of orbits that are geometrically $n$-leaf clovers in a precessing orbital plane. When viewed in the full three dimensions, these orbits are periodic in $r\ensuremath{-}\ensuremath{\theta}$. Each $n$-leaf clover is associated with a rational number, $1+{q}_{r\ensuremath{\theta}}={\ensuremath{\omega}}_{\ensuremath{\theta}}/{\ensuremath{\omega}}_{r}$, that measures the degree of perihelion precession in the precessing orbital plane. The rational number ${q}_{r\ensuremath{\theta}}$ varies monotonically with the orbital energy and with the orbital eccentricity. Since any bound orbit can be approximated as near one of these periodic $n$-leaf clovers, this special set offers a skeleton that illuminates the structure of all bound Kerr orbits, in or out of the equatorial plane.

Four leaf clover.

A 69-year-old male was evaluated for complaints of dyspnoea. Transthoracic echocardiography showed a moderate left ventricular systolic function. Although a significant aortic regurgitation was suspected, the valves could not be evaluated properly due to poor image quality. Consequently, transoesophageal echocardiography was performed which revealed a quadricuspid aortic valve (Fig. 1a and b). Only a moderate central aortic regurgitation was observed, valvular replacement was not indicated at the time. The ventricular dysfunction was found to be ischaemic of origin, the patient was treated successfully by percutaneous coronary intervention. Malformation of the semilunar valves is the most common congenital anomaly involving the heart. Bicuspid aortic valve affects the general population in approximately 2%. A quadricuspid aortic valve has an estimated incidence of only 0.008% to 0.043% [1]. It frequently results in progressive aortic regurgitation. In 114 reported cases, 46 patients underwent surgery during follow-up [2]. Therefore, an accurate diagnosis is important.