Hasil untuk "Aquaculture. Fisheries. Angling"

Juzheng Wang, Jianlong Du, Yueru Li et al.

Fatma H.A. Mustafa, Seham A.H. Hassan, Ola A. Ashary et al.

The shrimp aquaculture industry faces challenges that hinder production, including pathogens and infections from bacteria-causing diseases. The present study aimed to examine the impact of dietary synthesized chitosan stabilized selenium nanoparticles (CSSeNPs) on the growth performance of gut microbiota and immune-associated genes for shrimp L. vannamei aquaculture. The experiments were accomplished for 12 weeks in triplicate fiberglass circular tanks (200 L). A 300 shrimp post-larvae (PL) weighing an average of 0.14 ± 0.001 g was utilized. Four experimental groups were assigned to 12 tanks. Each tank contained 25 PL. Each group fed with one of the following diets: control (C), commercial diet without CSSeNPs (Control; T1), 25 mg/kg CSSeNPs (T2), 35 mg/kg CSSeNPs (T3), and 45 mg/kg CSSeNPs (T4). The specific growth rate (SGR) and feed conversion ratio (FCR) showed improvement (P ≤ 0.05) in the T2 and T3 groups compared to the control group. The relative expression of all examined genes LPS/b-glucan binding protein, glutathione peroxidase and superoxide dismutase (L-GBP, GPX, and SOD) were increased (P < 0.05) at T3. CSSeNPs demonstrated anti-fish pathogen efficacy against Gram-positive and Gram-negative bacteria. The Enterococcus faecalis bacterium displayed the highest vulnerability to inhibition. In contrast, Escherichia coli exhibited the lowest level of susceptibility. Moreover, a quantitative assessment of the prebiotic-like effect of CSSeNPs on shrimp gut showed increased lactic acid bacteria. Also, no Vibrio sp., Salmonella sp., Shigella sp., or Pseudomonas sp. were detected in the T3 group feed on 35 mg/Kg CSSeNPs. This work provides a new safe additive that is eco-friendly for the shrimp diet and improves growth, immunity, and disease control.

Guoqi ZHANG, Di MENG, Bin XIA et al.

Plastic products are widely used in human daily life, while facilitating human life, plastics have also produced many negative effects due to the lack of effective recovery measures, plastic pollution has become an important environmental issue of global concern. Marine plastics can be degraded into smaller microplastics (MPs) through various ways under the influence of environmental factors. They can be ingested by marine organisms mixed with food sources, and then accumulated in the body, causing serious negative effects on marine lifes and marine ecology. Recently, it has been proved that the Changshan Islands sediments contain a certain amount of MPs, the content reached 133.14 to 499.82 n/kg. Changshan Islands is one of the eight major islands in China. It is located at the confluence of the Yellow Sea and the Bohai Sea, and has a unique geographical location. The fish community between the islands is rich in species, especially in many migratory species, and high in species diversity. The seasonal change of fish species composition and dominant species is obvious. It has been proved MPs can cause a certain degree of harm to marine organisms. Therefore, the distribution of MPs in organisms in the Changshan Islands sea area deserves to be studied. In this study, the MPs in the gastrointestinal tracts and muscles of wild fish were digested and separated after collecting them from the marine culture zone of Changshan Islands. The results showed that MPs were detected existing in the gastrointestinal tracts of all fish, but not in muscle tissues. The reason may be that MPs are too large to be endocytosed by intestinal epithelial cells, and thus can not participate in the blood circulation of fish. The abundance of MPs in the gastrointestinal tracts of seven species of marine wild fish ranged from 0.19 to 3.79 items/individual. The abundance of MPs in Coilia nasus is the highest among all fish, this phenomenon may be related to the living environment and predation habits of C. nasus, which living in the bottom of the sea. The MPs in sediments will undergo a cyclic process of suspension, sedimentation and resuspension under the flow of seawater, thus greatly increasing the exposure and intake risk of MPs by bottom organisms, such as C. nasus. The shape of MPs was dominated by the fiber, and the color was mostly transparent, which size is mainly less than 300 μm. The reason may be that the individual size of fish collected in this survey is small, and larger-sized MPs cannot enter into the gastrointestinal tract of fish through feeding. Large plastics in the environment are broken under the photooxidation, wave action, physical wear and alternating freeze-thaw. The different shapes of MPs detected in this study may be derived from the decomposition of these large plastics. Fibers are the predominant form of MPs encountered in global wildlife studies. It could also be because fibrous MPs are the most abundant in the marine environment. Additionally, MPs Fibers can be bended or intertwined with food, possibly due to long-term accumulation for the slower fibers excretion, increasing the chance of being ingested by organisms. The types of polymers detected were cellophane, cellulose and polyethylene, among which cellophane had the highest content. Cellophane is an organic cellulose-based polymer that has been used in food packaging and cigarette packaging. It is also used as a release agent in the manufacture of glass fiber and rubber products, or as a coating in combination with synthetic polymers. There was no obvious toxic effect on cellulose and cellulite. The polymer hazard index (PHI) is an important criterion for risk assessment of MPs, and is based primarily on the percentage content of a given polymer and the polymer's hazard fraction for ecological and health risk assessment. The potential risk of MPs to humans can be estimated by the polymer hazard index. The higher the polymer hazard index, the higher the ecological risk in the sea area. The toxicity coefficient of polyethylene is 10, the toxicity grade is grade II, the hazard index is low, and it belongs to the low risk polymer. Moreover, people usually discard the gastrointestinal tract of fish before eating, thus the MPs in the fishes of Changshan Islands, and the safety factor of fish products in Changshan Islands is higher. In this study, through the collection of wild fish in Changshan Islands, the MPs in gastrointestinal tract and muscle tissue were extracted, and the abundance and type of MPs were analyzed. The pollution status of MPs in fish in the adjacent waters of Changshan Islands was clarified, which provided basic data for exploring the impact of MPs on the ecological environment safety of Changshan Islands ecosystem. Further research on the distribution of MPs in other wild organisms, such as shellfish, and in other economically viable locations should be considered, which can provide a scientific basis for the analysis of MP pollution levels and the formulation of prevention and control strategies in the marine environment.

Barra Muzaffar Widayat, Delianis Pringgenies, Wilis Ari Setyati

This study aims to explore biosynthetic gene clusters and antibacterial activity in mangrove sediment bacteria at Tirang Beach, Semarang, Central Java. Research methods include isolating bacteria from seagrass sediments, antibacterial testing against S. aureus and E. coli bacteria, identifying bacteria using the DNA method, and testing the presence of biosynthetic gene clusters. The results showed that the mangrove sediment bacterial isolate with the isolate code B.26.ST.3.4 had the highest antibacterial activity with a value of 28.05 ± 0.9192 against the pathogen E. coli and 23.45 ± 10.2530 against the pathogen S. aureus. Apart from that, there are two other isolates that also have antibacterial activity. Based on bacterial DNA identification, mangrove sediment bacteria that have potential as antibacterials are Bacillus velezensis (B.9.ST.1.4), Bacillus subtilis (B.13.ST.2.2), and Bacillus amyloliquefaciens (B.26.ST.3.4). These three isolates have the NRPS gene, and isolate B.9.ST.1.4 also has the PKS-II gene, while isolate B.26.ST.3.4 has the PKS-I gene. This discovery provides a deeper understanding of the antibacterial potential of mangrove sediment bacteria at Tirang Beach, Semarang. This information can be used to develop natural antibiotics that are more effective and have the potential to fight bacterial infections that are increasingly resistant to conventional antibiotics. The conclusion is that bacteria have potential as antibacterials from mangrove sediment bacteria at Tirang Beach, Semarang through isolation and identification of bacteria. Isolate B.26.ST.3.4 has the highest antibacterial activity against E. coli and S. aureus pathogens. Apart from that, Bacillus velezensis, Bacillus subtilis, and Bacillus amyloliquefaciens also have antibacterial potential. The NRPS gene was found in all three isolates, while isolate B.9.ST.1.4 also had the PKS-II gene and isolate B.26.ST.3.4 had the PKS-I gene. This discovery can provide a deeper understanding of the natural antibiotic potential of mangrove sediment bacteria and can be the basis for further development in the pharmaceutical field.     Penelitian ini bertujuan untuk mengeksplorasi klaster gen biosintesis dan aktivitas antibakteri pada bakteri sedimen mangrove di Pantai Tirang, Semarang, Jawa Tengah. Metode penelitian meliputi isolasi bakteri dari sedimen lamun, uji antibakteri terhadap bakteri S. aureus dan E. coli, identifikasi bakteri dengan metode DNA, dan uji keberadaan klaster gen biosintesis. Hasil penelitian menunjukkan bahwa isolat bakteri sedimen mangrove dengan kode isolat B.26.ST.3.4 memiliki aktivitas antibakteri tertinggi dengan nilai 28,05±0,9192 terhadap patogen E. coli dan 23,45±10,2530 terhadap patogen S. aureus. Selain itu, terdapat dua isolat lain yang juga memiliki aktivitas antibakteri Berdasarkan identifikasi bakteri DNA, bakteri sedimen mangrove yang potensial sebagai antibakteri adalah Bacillus velezensis (B.9.ST.1.4), Bacillus subtilis (B.13.ST.2.2), dan Bacillus amyloliquefaciens (B.26.ST.3.4). Ketiga isolat ini memiliki gen NRPS, dan isolat B.9.ST.1.4 juga memiliki gen PKS-II, sedangkan isolat B.26.ST.3.4 memiliki gen PKS-I. Penemuan ini memberikan pemahaman yang lebih dalam tentang potensi antibakteri dari bakteri sedimen mangrove di Pantai Tirang Semarang. Informasi ini dapat digunakan untuk mengembangkan antibiotik alami yang lebih efektif dan memiliki potensi dalam melawan infeksi bakteri yang semakin resisten terhadap antibiotik konvensional. Kesimpulan bahwa bakteri potensi sebagai antibakteri dari bakteri sedimen mangrove di Pantai Tirang, Semarang melalui isolasi dan identifikasi bakteri. Isolat B.26.ST.3.4 memiliki aktivitas antibakteri tertinggi terhadap patogen E. coli dan S. aureus. Selain itu, Bacillus velezensis, Bacillus subtilis, dan Bacillus amyloliquefaciens juga memiliki potensi sebagai antibakteri. Gen NRPS ditemukan pada ketiga isolat tersebut, sedangkan isolat B.9.ST.1.4 juga memiliki gen PKS-II dan isolat B.26.ST.3.4 memiliki gen PKS-I. Penemuan ini dapat memberikan pemahaman yang lebih dalam tentang potensi antibiotik alami dari bakteri sedimen mangrove dan dapat menjadi dasar untuk pengembangan lebih lanjut dalam bidang farmasi.

Fazeel Mohammed, Paul Gabbadon, Tahmina Ajmal et al.

Abstract In recirculating aquaculture systems (RAS), understanding the relationship between feed load and its impact on water quality and overall shrimp health is important. This study utilised an indoor marine RAS for the intensive culture of Pacific white shrimp Litopenaeus vannamei. The shrimp were stocked into the grow‐out system at an average body weight of 0.25 g and a stocking density of 347 shrimp/m3. Water quality parameters of temperature, salinity, total dissolved solids, pH, and dissolved oxygen (DO) were measured twice daily. Total ammonia nitrogen (TAN), nitrite and nitrate were measured once weekly or when needed. Sampling was conducted to calculate the daily feed ratio based on the total estimated biomass. Mortality was recorded as a means of evaluating the overall shrimp health. The data obtained were analysed using Pearson correlation (r) analysis and multi‐linear regression with a significant difference accepted p < 0.05. Correlation (r) established relationships among the water quality parameters, feed load and mortality. The TAN level of 24.20 mg/L was recorded when the feed load increased by 81.2% resulting in the mortality of 40% of shrimp. A negative correlation between TAN and DO resulted in a synergistic effect causing a massive consumption of DO in the water, reducing its availability to the shrimp and leading to a drastic change in the shrimp's behaviour. Overfeeding can lead to an accumulation of uneaten feed and waste, causing ammonia spikes and oxygen depletion in the water. Monitoring and adjusting feed rates accordingly can help maintain optimal water conditions for shrimp growth and health. Therefore, it is essential to use appropriate feed rates in recirculating systems because feed load can influence water quality parameters that can be detrimental to shrimp culture.

Shubha Vij, Yeng Sheng Lee, Kathiresan Purushothaman et al.

Singapore’s aquaculture sector is critical to achieving the nation’s ‘30 by 30’ food security goal, which aims to produce 30% of its nutritional needs locally by 2030. However, the sector faces several significant challenges. Limited land and water resources, high operational costs, disease outbreaks, reliance on imported seedstock, and environmental impact are among the key issues. Additionally, the industry struggles with a shortage of skilled manpower and high dependency on foreign labour. This study explores these challenges in detail and suggests potential solutions to enhance the sustainability and productivity of Singapore’s aquaculture. Innovative farming techniques such as recirculating aquaculture systems (RASs) and vertical farming, advanced water quality management, and the adoption of renewable energy sources are recommended to address space and cost constraints. Developing local breeding facilities, enhancing education and training programs, and adopting sustainable practices are also crucial. The establishment of a national hatchery and increased investment in research and development (R&D) are essential for long-term growth. By implementing these strategies, Singapore can overcome the challenges in its aquaculture sector and ensure a sustainable future for local food production.

Peter J. Mohr, Eric Shirley, William D. Phillips et al.

We examine implications of angles having their own dimension, in the same sense as do lengths, masses, {\it etc.} The conventional practice in scientific applications involving trigonometric or exponential functions of angles is to assume that the argument is the numerical part of the angle when expressed in units of radians. It is also assumed that the functions are the corresponding radian-based versions. These (usually unstated) assumptions generally allow one to treat angles as if they had no dimension and no units, an approach that sometimes leads to serious difficulties. Here we consider arbitrary units for angles and the corresponding generalizations of the trigonometric and exponential functions. Such generalizations make the functions complete, that is, independent of any particular choice of unit for angles. They also provide a consistent framework for including angle units in computer algebra programs.

Sergiy Koshkin

A horn angle between a circle and its tangent is considered in Euclid's Elements, and Euclid remarks that it is smaller than any acute rectilinear angle. Already in antiquity, Proclus wondered whether it is possible to bisect horn angles. We will give a construction of a bisector which was within the means of ancient geometers since the time of Archimedes and Apollonius. We will also compare it to the conformal bisection method introduced in modern times.

Nur Hikmah Mazroatum Maslahah, Max Rudolf Muskananfola, Pujiono Wahyu Purnomo

Perairan Teluk Awur merupakan perairan dengan karakteristik gelombang yang tidak begitu besar dan daerah yang landai dengan substrat dasar berupa pasir dan pecahan karang, sehingga lokasi tersebut banyak ditemukan keanekaragaman sumber daya laut, diantaranya adalah makroalga. Penelitian ini bertujuan untuk mengetahui keanekaragaman jenis makroalga dan kandungan klorofil makroalga hijau dominan serta faktor fisika kimia yang mempengaruhi kandungan klorofil makroalga. Metode yang digunakan penelitian ini adalah metode studi kasus yang dianalisis secara deskriptif dan analisis statistik uji One Way ANOVA dan Principal Component Analysis. Pengambilan sampel menggunakan teknik sampling secara purposive random sampling. Kandungan klorofil diukur dengan menggunakan Spektrofotometer UV-Vis dengan panjang gelombang 645 dan 663 nm. Makroalga yang ditemukan di Perairan Teluk Awur, Jepara yaitu spesies Caulerpa racemosa, Halimeda opuntia, Halimeda macroloba, Sargassum polycystum, Padina australis dan Halymenia durvillaei. Hasil kandungan klorofil a, klorofil b, dan klorofil total berturut-turut dari makroalga hijau dominan spesies Caulerpa racemosa, Halimeda opuntia dan Halimeda macroloba berkisar antara 1,311-9,299 mg/L, 2,080-12,409 mg/L, dan 3,390-20,167 mg/L. Indeks keanekaragaman tergolong rendah (0-0,820), indeks keseragaman  sedang (0-0,458) dan indeks dominansi pada kategori tinggi (0-1). Hasil uji analisis statistik dengan One Way ANOVA bahwa tidak terdapat perbedaan signifikan antara jenis kandungan klorofil makroalga dengan jenis makroalga di Teluk awur, sedangkan hasil uji dengan metode PCA bahwa faktor yang paling berpengaruh terhadap kandungan klorofil diantaranya adalah variabel pH, DO, kecerahan, kecepatan arus, nitrat, dan fosfat, sedangkan faktor yang berpengaruh kecil terhadap kandungan klorofil a, klorofil b, dan klorofil total makroalga diantaranya adalah variabel suhu, intensitas cahaya, salinitas, dan kedalaman perairan.

Sajeenuth Srithongthum, Hsein-Loong Au, Thumronk Amornsakun et al.

Highlight Research • The reproductive characteristics of L. hoevenii were examined • The potentially smallest maturity sizes of female and male L. hoevenii were 350 g and 180 g, respectively • The fecundity of a 1,000 g L. hoevenii can be more than 100,000 eggs • L. hoevenii was determined as a multiple spawner Abstract Sultan fish (Leptobarbus hoevenii) is a high value freshwater fish, cultured in some Southeast Asian countries, including Malaysia and Thailand. However, information on its reproductive characteristics is very scarce. This study examined the gonadosomatic index (GSI), fecundity, egg diameter, and determined whether L. hoevenii is a single- or multiple-spawner. Twenty male and female pond-farmed L. hoevenii broodstock were obtained to measure their total length (TL), body weight (BW) and gonad weight to calculate the GSI. Ten females were randomly sampled from the 20 to determine their fecundity. A total of 1,500 eggs were sampled from each female. The egg diameter was measured then its frequency distribution was analyzed to detect the number of egg class group, and to determine whether L. hoevenii is a single- or multiple spawner. The female L. hoevenii examined were 32.2-47.1 cm and 350-1,200 g, while the males were 30.7-45.8 cm and 180-970 g in TL and BW, respectively. All female specimens contained gonads. The potentially smallest mature samples were recorded at 350 g (female) and 180 g (male). GSI for the female and male L. hoevenii were 1.81-12.28 % and 1.03-5.09 %, respectively. The fecundity was 35,467 -128,067 eggs, while the highest fecundity was observed in a 1,000 g fish. The observed egg diameter ranged from 500 to 1,855 μm. Two to five groups of egg class were detected, indicating that L. hoevenii is a multiple spawner.

Paul Quincey

The specialised uses of solid angles mean that they are quite unfamiliar quantities. This article, apart from making solid angles a little more familiar, brings out several topics of general interest, such as how units are interrelated and how equations depend on the choice of units. Although the steradian is commonly used as the unit for solid angle, another unit, the square degree, is used in astronomy, and a unit introduced here, the solid degree (with 360 solid degrees in a hemisphere) could be used with benefits that are similar to those of the degree when it is used as the unit for plane angle. The article, which is suitable for students at A-level and introductory undergraduate level, also shows how solid angles can provide a gentle introduction to crystal structure, spherical trigonometry and non-Euclidean geometry.

Pedro J. Freitas

We prove that the golden angle (an angle that divides the circle in the golden ratio) is not constructible using straightedge and compass.

Victor Pacheco-Peña, Nader Engheta

Controlling amplitude, phase and polarization of electromagnetic waves is key for a full manipulation of wave-matter interactions. The Brewster angle is one of the important features in this context. Here, we exploit metamaterial concepts with a time-modulated permittivity to propose the temporal equivalent of the spatial Brewster angle, a concept we call temporal Brewster angle. We consider temporal boundaries (as the temporal equivalent of the spatial boundaries between two media) by rapidly changing the permittivity of the medium, where a wave travels, from isotropic to an anisotropic permittivity tensor. It is theoretically shown that when the incidence angle coincides with that of the temporal Brewster angle a forward (temporal transmission) wave is produced while the backward (temporal reflection) is eliminated. We provide a closed-form analytical expression of the temporal Brewster angle and demonstrate its performance both theoretically and numerically. Our findings may provide a fresh view on how to control electromagnetic wave propagation and wave-matter interactions in real time using temporal metamaterials.

A. Schäpers, J. Sonntag, L. Valerius et al.

Van der Waals layered materials with well-defined twist angles between the crystal lattices of individual layers have attracted increasing attention due to the emergence of unexpected material properties. As many properties critically depend on the exact twist angle and its spatial homogeneity, there is a need for a fast and non-invasive characterization technique of the local twist angle, to be applied preferably right after stacking. We demonstrate that confocal Raman spectroscopy can be utilized to spatially map the twist angle in stacked bilayer graphene for angles between 6.5° and 8° when using a green excitation laser. The twist angles can directly be extracted from the moiré superlattice-activated Raman scattering process of the transverse acoustic (TA) phonon mode. Furthermore, we show that the width of the TA Raman peak contains valuable information on spatial twist angle variations on length scales below the laser spot size of ~ 500 nm.

Chao Chen, Di Zhao, Sei Zhen Khong

In this paper, we introduce an angle notion called the singular angle for nonlinear systems from an input-output perspective. The proposed system singular angle, based on the angle between $L_2$-signals, describes an upper bound for the ''rotating effect'' from system input to output signals. It quantifies passivity and serves as a counterpart to system $L_2$-gain. It also provides an alternative to a recently defined notion of system phase which adopts complexification of real-valued signals via the Hilbert transform. A nonlinear small angle theorem is established for feedback stability analysis, which involves a comparison of the loop system angle with $π$. The theorem generalizes the classical passivity theorem via a tradeoff between the singular angles of open-loop systems.

William Evans, Ellen Gethner, Jack Spalding-Jamieson et al.

Consider a graph with a rotation system, namely, for every vertex, a circular ordering of the incident edges. Given such a graph, an angle cover maps every vertex to a pair of consecutive edges in the ordering -- an angle -- such that each edge participates in at least one such pair. We show that any graph of maximum degree 4 admits an angle cover, give a poly-time algorithm for deciding if a graph with no degree-3 vertices has an angle-cover, and prove that, given a graph of maximum degree 5, it is NP-hard to decide whether it admits an angle cover. We also consider extensions of the angle cover problem where every vertex selects a fixed number $a>1$ of angles or where an angle consists of more than two consecutive edges. We show an application of angle covers to the problem of deciding if the 2-blowup of a planar graph has isomorphic thickness 2.

Yixing Fu, E. J. König, J. H. Wilson et al.

Breakthroughs in two-dimensional van der Waals heterostructures have revealed that twisting creates a moiré pattern that quenches the kinetic energy of electrons, allowing for exotic many-body states. We show that cold-atomic, trapped ion, and metamaterial systems can emulate the effects of a twist in many models from one to three dimensions. Further, we demonstrate at larger angles (and argue at smaller angles) that by considering incommensurate effects, the magic-angle effect becomes a single-particle quantum phase transition (including in a model for twisted bilayer graphene in the chiral limit). We call these models "magic-angle semimetals." Each contains nodes in the band structure and an incommensurate modulation. At magic-angle criticality, we report a nonanalytic density of states, flat bands, multifractal wave functions that Anderson delocalize in momentum space, and an essentially divergent effective interaction scale. As a particular example, we discuss how to observe this effect in an ultracold Fermi gas.

Zeév Rudnick, Ezra Waxman

Fermat showed that every prime p = 1 mod 4 is a sum of two squares: $p = a^2 + b^2$. To any of the 8 possible representations (a,b) we associate an angle whose tangent is the ratio b/a. In 1919 Hecke showed that these angles are uniformly distributed as p varies, and in the 1950's Kubilius proved uniform distribution in somewhat short arcs. We study fine scale statistics of these angles, in particular the variance of the number of such angles in a short arc. We present a conjecture for this variance, motivated both by a random matrix model, and by a function field analogue of this problem, for which we prove an asymptotic form for the corresponding variance.

Ana Mansourkiaei, Pargol Ghavam Mostafavi, Seyed Mohammad Reza Fatemi et al.

Abstract Narrow-barred Spanish mackerel, Scomberomorus commerson, is an epipelagic and migratory species of family Scombridae which have a significant role in terms of ecology and fishery. 100 samples were collected from the Persian Gulf, Oman Sea and Arabian Sea. Part of their dorsal fins was snipped and transferred to micro-tubes containing ethanol; then, DNAs were extracted and HRM-Real Time PCR was performed to designate representative specimens for sequencing. Phylogenetic relationships of S. commerson from Persian Gulf, Oman Sea and Arabian Sea were investigated using sequence data of mitochondrial DNA D-loop region. None clustered Neighbor Joining tree indicated the proximity amid S. commerson in four sites. As numbers demonstrated in sequence analyses of mitochondrial DNA D-Loop region a sublimely high degree of genetic similarity among S. commerson from the Persian Gulf and Oman Sea were perceived, thereafter, having one stock structure of S. commerson in four regions were proved, and this approximation can be merely justified by their migration process along the coasts of Oman Sea and Persian Gulf. Therefore, the assessment of distribution patterns of 20 haplotypes in the constructed phylogenetic tree using mtDNA D-Loop sequences ascertained that no significant clustering according to the sampling sites was concluded.

Ciro Semprebon, Glen McHale, Halim Kusumaatmaja

We theoretically investigate the apparent contact angle and contact angle hysteresis of a droplet placed on a liquid infused surface. We show that the apparent contact angle is not uniquely defined by material parameters, but also has a strong dependence on the relative size between the droplet and its surrounding wetting ridge formed by the infusing liquid. We derive a closed form expression for the contact angle in the limit of vanishing wetting ridge, and compute the correction for small but finite ridge, which corresponds to an effective line tension term. We also predict contact angle hysteresis on liquid infused surfaces generated by the pinning of the contact lines by the surface corrugations. Our analytical expressions for both the apparent contact angle and contact angle hysteresis can be interpreted as `weighted sums' between the contact angles of the infusing liquid relative to the droplet and surrounding gas phases, where the weighting coefficients are given by ratios of the fluid surface tensions.