Centrifugal Sedimentation Method Research Articles

Gastrointestinal parasite infections and associated factors in fighting bulls over 7 years of monitoring in Southern Thailand.

Indigenous beef cattle engaged in bullfighting in Southern Thailand represent a distinctive and valuable breed. Gastrointestinal (GI) parasites, which are recognized as important pathogens, have a negative impact on the overall health and physical performance of these fighting bulls. This study aimed to estimate the prevalence of GI parasitic infections and identify factors associated with these infections in a fighting bull population in Southern Thailand. Fecal samples (n = 4,244) from fighting bulls were submitted to the Laboratory and Diagnostic Centre of the Teaching Animal Hospital, Faculty of Veterinary Science, Rajamangala University of Technology Srivijaya. We examined the samples using simple flotation and centrifugal sedimentation methods. Individual animal profiles and demographic data were collected. The overall prevalence of GI parasitic infections was 93.2%. Nine GI parasites were identified as Paramphistome spp. [PP]. being the most prevalent (93.2%), and the highest annual prevalence occurred in 2019 (97.9%). The infection rates of various parasite species were significantly related to the years of study, geographic area, season, and age group (p < 0.05). The prevalence of parasitic infection was higher on the west coast (98.6%) than on the east coast (98.0%). PP, Eurytrema spp., Strongyles spp., and Buxtonella spp. infections differed significantly among the seven provinces of Southern Thailand (p < 0.05). The prevalence of GI parasitic infections was higher during the rainy season (98.5%) than during the summer (97.7%). Bulls aged 7.0-7.9 years and 8.0-8.9 years had the highest parasite infection rate (99.2%) compared with those aged 8.0-8.9. GI parasitic infections continue to be a significant health concern among fighting bulls in Southern Thailand. Regular epidemiological investigations are crucial for developing effective preventive programs and control strategies and providing basic knowledge for bull farmers.

Laser scattering centrifugal liquid sedimentation method for the accurate quantitative analysis of mass-based size distributions of colloidal silica.

This paper proposes a laser scattering centrifugal liquid sedimentation (LS-CLS) method for the accurate quantitative analysis of the mass-based size distributions of colloidal silica. The optics comprised a laser diode light source and multi-pixel photon-counting detector for detecting scattered light intensity. The unique optics can only detect the light scattered by a sample through the interception of irradiated light. The developed centrifugal liquid sedimentation (CLS) method comprised a light-emitting diode and silicon photodiode detector for detecting transmittance light attenuation. The CLS apparatus could not accurately measure quantitative volume- or mass-based size distribution of poly-dispersed suspensions, such as colloidal silica, because the detecting signal includes both transmitted and scattered light. The LS-CLS method exhibited improved quantitative performance. Moreover, the LS-CLS system allowed the injection of samples with concentrations higher than that permitted by other particle size distribution measurement systems with particle size classification units using size-exclusion chromatography or centrifugal field-flow fractionation. The proposed LS-CLS method achieved an accurate quantitative analysis of the mass-based size distribution using both centrifugal classification and laser scattering optics. In particular, the system could measure the mass-based size distribution of approximately 20mgmL-1 poly-dispersed colloidal silica samples, such as in a mixture of the four mono-dispersed colloidal silica, with high resolution and precision, thereby demonstrating high quantitative performance. The measured size distributions were compared with those observed through transmission electron microscopy. The proposed system can be used in practical setups to achieve a reasonable degree of consistency for determining particle size distribution in industrial applications.

CNF Dispersion Evaluation by Particle Size Distribution Measurement Using High Resolution Disc Centrifugal Sedimentation Method

CNFは一般的に湿式条件下で機械的処理によって微細化され，物性制御や有効活用する上で分散性の評価，とりわけ粒子径分布評価は重要である。粒子径分布計測には様々な原理，手法があるが幅広い分布を持つ粒子や異形粒子の測定は困難であり正確な分布が得られない課題がある。解繊の過程において様々な粒子径が同時に存在していることが多いCNFの評価においては，分解能の高い計測法が必要となる。ディスク遠心沈降方式粒子径分布測定法は，多くの計測法で用いられるフィッティングアルゴリズムを用いずに直接的に粒子を観測しており，さらに一旦各サイズごとに分級してから粒子を検出する方式のため分解能が非常に高い方式である。このディスク遠心沈降方式粒子径分布測定法を用いて処理回数の異なる6種類のCNF試料の粒子径分布の測定を行った。処理回数の少ない試料では，数十nmから数µmにかけて3つのピークをもつ分布が得られた。処理回数の増加につれて数µmのピークは消失し，数百nmのピークの減少が見られると同時に数十nmのピークは増加した。再現性もおおむね良好であった。ディスク遠心沈降方式粒子径分布測定法を用いることでCNFの物性制御や有効活用への利用が期待できる。

Blood and urinary parasites and associated risk factors in a rural community in Abia State, Nigeria

The environment, climate, social behaviour, and economic factors make developing countries vulnerable to parasitic infections. A cross-sectional study was conducted (Dec 2017-May 2018) to determine the prevalence of blood and urine parasites in Obizi, Amakama-Olokoro, a rural community in Umuahia South LGA, Abia State. Blood and urine samples were collected from 284 respondents. Sample analyses were done using Rapid Diagnostic Test (RDT) kits and microscopy for blood and centrifugal sedimentation method for urine. Socio-demographic data and risk factors were collected with structured questionnaires. Statistical analysis was done using the Pearson’s Chi-square, with the PAST Statistical package. The results showed an overall blood parasitic prevalence of 32.4%. Plasmodium falciparum recorded the highest prevalence of 28.17% by RDT and 30.6% by microscopy. Trypanosoma brucei gambiense occurred as a mixed infection (1.8%). Schistosoma haematobium had a prevalence of 3.9%. Socio-demographic data showed there were more females (67.3%); more persons in the age group 61-70 years (31.0%) and more farmers (38.0%) in the studied population. More females were infected with Plasmodium falciparum (34.6%) while more males were infected with Schistosoma haematobium (8.6%) P. falciparum occurred in all the age groups. S. haematobium occurred only in three age groups with the highest prevalence found in the age group (11-20) years (26.9%). Malaria infection was higher in those who did not use ITNs (37.1%). Some reasons given for the non-usage of ITNs were high cost/non-availability and discomfort. Farming activities and swimming have been recognized as risk factors to the acquisition of Trypanosoma brucei gambiense and Schistosoma haematobium, respectively. Plasmodium falciparum, Trypanosoma brucei gambiense and Schistosoma haematobium still pose a serious health threat to the community. Eliminating vector breeding sites, the use of ITNs and changes in social behaviours will help reduce blood and urinary parasites and ensure a healthier and economically viable community.

Haemoparasites and Polyparasitism of Intestinal Helminths among Cattle Slaughtered in Selected Abattoirs in Abeokuta, Ogun State.

Background: Haemoparasites and intestinal helminths are significant constraints to livestock production resulting in substantial economic loss, and some helminth parasites of cattle are of serious public health concern. This study investigated the prevalence of haemoparasites and polyparasitism of intestinal helminths amongst cattle slaughtered in two major abattoirs of Abeokuta metropolis and their implications for public health. Methods: Blood and faecal samples were randomly collected from 256 cattle less than two and greater than two years of age. Blood samples were screened for Packed Cell Volume (PCV) using the haematocrit centrifuge technique and parasites were detected by microscopy using a wet mount, buffy coat and stained thin smear. Helminth eggs and oocysts were detected using centrifugal sedimentation and centrifugal faecal flotation method. Results: Results showed prevalence for Trypanosoma spp., Babesia spp., Anaplasma spp. and Theileria spp. to be 8.3%, 27.34%, 20.7% and 0.39%, respectively. For intestinal parasites, the prevalence for Strongyle eggs is 73.82%, Neoascaris vitulorum 0.8%, Fasciola spp. 10.15%, Moniezia spp. 4.3%, Eimeria oocyst 35.94% and Cryptosporidium oocyst was 1.17%. The total prevalence of coinfection of haemoparasite and intestinal helminths was 42.6%. Breed-specific prevalence for co-infection of haemoparasites and intestinal parasites showed 55.96%, 37.6% and 6.4% for White Fulani, Red Bororo and Sokoto Gudali, respectively which was statistically insignificant (p &gt; 0.05). With regards to sex, females had a higher prevalence of 92 (84.4%) of coinfection of haemoparasites and intestinal helminths than males 17 (15.6%), which was statistically significant (p&lt;0.05). Conclusion: This study revealed a high prevalence of haemoparasites and intestinal parasites in cattle slaughtered in Abeokuta, Nigeria. Therefore, the study recommends strict compliance with meat inspection at abattoirs and the need for immediate operationalisation and implementation of a sustainable Preventive One Health intervention to mitigate against the outbreak of zoonoses in Abeokuta.

Evaluation of fecal smear methods for research on Cryptosporidium spp. oocysts in the feces of dairy calves

The objective of this study is to compare the direct fecal smear (DFS) and centrifugal sedimentation (CS) methods in the detection of Cryptosporidium spp. oocysts in fecal samples of dairy calves. One hundred and fourteen fecal samples were collected from calves aged up to six months from 10 dairy farms located in Palotina and Francisco Alves, Paraná, Brazil. The microscopic analysis revealed the presence of Cryptosporidium spp. oocysts in 51.75% (59/114) of the samples in both methods. In CS, 48.25% (55/114) of the samples were positive, while in DFS slides, only 6.14% (7/114) were positive. Only 4 samples were positive exclusively in DFS. To ensure that there were no false-negative results in the microscopic analysis, the 55 samples that were negative in both DFS and CS were selected for molecular analysis using the nested PCR (nPCR). Of these 55 samples, 24% (13/55) were positive and forwarded for sequencing part of the genome, which made it possible to identify C. parvum, C. bovis and C. ryanae. Besides the characterization of the Cryptosporidium species, it was possible to identify bacteria of the genus Acinetobacter interfering directly in the analyzed samples. The microscopic analysis also revealed higher sensitivity when CS was used to make the fecal smears. However, some samples that were negative in this technique had positive PCR results. Thus, molecular analysis is indicated to confirm cases of Cryptosporidium spp. Further studies are necessary to prove the specificities of the used primers since the results obtained in nPCR were positive for the protozoan but, when genetic sequencing was performed, Acinetobacter spp. was identified.

Using Disposable Membrane Cell Collector to Enrich Lung Adenocarcinoma Cells in Bloody Pleural Effusion for Anaplastic Lymphoma Kinase Fusion Gene Detection

Purpose: For anaplastic lymphoma kinase (ALK) gene detection, the centrifugal sedimentation method (CSM) and cell block method (CBM) are commonly used to process samples of bloody pleural effusions (BPEs). However, in practice, the impurity content in the processed samples often affects the results and even leads to the detection failure. The purpose of this study was to establish a cell enrichment method (CEM) by using a disposable membrane cell collector to remove blood and inflammatory cells and enrich lung adenocarcinoma cells in BPE for more efficient RNA extraction and ALK gene detection. Materials and Methods: CEM proposed in this study and the traditional CSM and CBM were used to treat BPE samples collected from 37 lung adenocarcinoma patients. A DeNovix DS-11 ultraviolet spectrophotometer was used to measure the concentration and purity of extracted RNA. Amplification refractory mutation systems (ARMS) and ABI 7500 fluorescence qPCR were used to detect ALK gene. Through statistical analysis, the CEM was compared with the CSM and CBM in RNA concentration, purity, and ALK gene detection results. Results: The concentration of RNA extracted by using the CEM was significantly higher than that extracted by using the CBM and CSM (p < 0.001). The purity of RNA extracted by using the CEM was significantly higher than that by the other 2 methods (p = 0.011, p = 0.005). ALK gene testing with PCR was successful in all the samples using the CEM, but 2 cases by the CSM and 1 case by the CBM failed. Conclusions: Using the disposable membrane cell collector to process BPE of lung adenocarcinoma patients for RNA extraction and ALK gene detection is more effective and successful compared with the traditional methods, and it is suggested to be further applied and popularized in clinical practice.

Validation of a Homogeneous Incremental Centrifugal Liquid Sedimentation Method for Size Analysis of Silica (Nano)particles

Silica nanoparticles display many unique physicochemical properties that make them desirable for use in a wide variety of consumer products and composite materials. Accurately measuring the size of these nanoparticles is important for achieving the desired nanoscale functionality of the final product and for regulatory compliances. This study covers the validation of a centrifugal liquid sedimentation method for accurate measurement of the Stokes diameter of silica particles with a near-spherical shape and dimensions in the nanometer and sub-nanometer scale range. The validated method provided unbiased results in the range of 50 nm to 200 nm, with a lower limit of detection of ≤20 nm. The relative standard uncertainties for precision, quantified in terms of repeatability and day-to-day variation, ranged from 0.2% to 1.0% and from <0.1% to 0.5%, respectively. The standard uncertainty for trueness was assessed at 4.6%. Within its working range, the method was found robust with respect to the type of cuvette, light factor, operator, and for defining the meniscus of the sample suspension. Finally, a relative expanded measurement uncertainty of 10% confirmed the satisfactory performance of the method.

Detection and Identification of Toxocara Canis in Infected Dogs Using PCR.

SummaryFaecal samples were collected from 224 dogs (47 villages) in Ankara. Toxocara spp. eggs were diagnosed in faeces using centrifugal flotation and sedimentation methods. A total of 21 dogs (9.38 %) were positive for Toxocara spp. eggs. In this study, we used the PCR technique that, in combination with DNA sequencing, allows the detection and identification of T.canis eggs in faeces of infected dogs. For this purpose, the ATPase subunit-6 gene (mtDNA) was selected as a target for the amplification T. canis. The primers were used to amplify 217 bp region. Amongst 21 coproscopically detected Toxocara isolates from dogs, 5 (23.8 %) samples were PCR-positive for T. canis, and the remaining 16 samples were PCR-negative. Results indicate that PCR can detect Toxocara canis DNA in faeces of infected dogs, but efficacy was low when compare to sedimentation/flotation. PCR is additional test for diagnosing of this infection. But, the difficulties of identification based on PCR in faecal examinations need to be investigated further.

Optimization of linalool-loaded solid lipid nanoparticles using experimental factorial design and long-term stability studies with a new centrifugal sedimentation method

Linalool (C10H18O), also known as 3, 7-dimethyl-1, 6-octadien-3-ol, is the most common acyclic monoterpene tertiary alcohol present in essential oils of several aromatic plant species. Previous studies indicate that linalool is a valuable compound with a wide range of therapeutic properties. The promising therapeutic effects of linalool are however limited by its poor water solubility and volatility. Recently, the encapsulation of linalool in drug delivery systems, such as solid lipid nanoparticles (SLN) and nanostructured lipid carriers (NLC) has demonstrated to overcome linalool physicochemical limitations. The present study aimed the production and optimization of linalool encapsulation in SLN applying the experimental full factorial design. The estimation of the long-term stability of the produced linalool-loaded SLN was carried out using a new centrifugal sedimentation method, LUMiSizer®. SLN dispersions were produced by the hot high pressure homogenization (HPH) method. The influence of the independent variables, surfactant and lipid concentrations on linalool-loaded SLN particle size, polydispersity index (PI) and zeta potential (ZP) was evaluated by a 22 factorial design composed of 2 variables which were set at 2-levels each. For each of the three dependent variables, analysis of the variance (ANOVA) was performed using a 95% confidence interval. The concentration of surfactant, as well as, the interaction between the different concentrations of lipid and surfactant, hada statistically significant effect on the particle size and PI. Experimental factorial design has been successfully employed to develop an optimal SLN dispersion, requiring a minimum of performed experiments. Based on the obtained results, the optimal linalool-loaded SLN dispersion was composed of 1% (w/v) linalool 2% (w/v) of solid lipid and 5% (w/v) of surfactant. Furthermore, the stability analysis revealed that the produced linalool-loaded SLN dispersions have limited storage stability which can be easily overcome through the assembly of a polymeric coating on the SLN surface. LUMiSizer® has been successfully used in the kinetic analysis of linalool-SLN during accelerated storage time.

Gastrointestinal parasites of Asian elephants (Elephas maximus L. 1798) in south Wayanad forest division, Kerala, India.

Microscopic-coprological examination of Asian Elephant (Elephas maximus L., 1798) dung piles (n = 55) in South Wayanad Forest Division from March to August, 2017 revealed 74.5% prevalence of parasites in elephants. Ancylostoma sp. Anoplocephala sp., Strongyle type egg and Strongyloides sp. were the major parasites recorded. Strongyloides sp. and Strongyle type egg were observed more frequently (58.1%). Ancylostoma sp. and Anoplocephala sp. were constituted 1.8% each; mixed parasitic species infections were recorded. The frequency distribution of parasitic load in elephants showed skewed distribution of propagules. Centrifugal sedimentation and floatation methods of fecal examination of outer and inner regions of dung did not show significant difference in number of propagules. The highest number of parasitic propagules was recorded in floatation method. The number of propagules varied among dung samples of different herds collected from different localities. There were no relation between the parasitic load and age of elephants. The mean density of parasite eggs was higher in solitary animals (214.3 ± 155.4 epg) than herd elephants (147.78 ± 111.1 epg). Though parasitic load was higher in solitary males, based on the occurrence of parasites using logistic regression it was found that females had 1.83 times higher occurrence for parasitic infection than males. Both length and width of parasite egg size classes were used to classify into different taxonomic groups using discriminate function analysis. Three distinct size clusters were identified. Nematode and Cestode eggs were classified correctly with 95.7% accuracy. Since, the egg size was similar in nematode group separation into genus was difficult. Further, inclusion of stages of development of egg and larvae enable better separation.

A new method for assessment of the sludge disintegration degree with the use of differential centrifugal sedimentation

ABSTRACTA novel method for assessing the disintegration degree (DD) of waste activated sludge (WAS) with the use of differential centrifugal sedimentation method (DCS) was shown herein. The method was validated for a WAS sample at four levels of disintegration in the range of 14.4–82.6% corresponding to the median particle size range of 8.5–1.6 µm. From the several sludge disintegration methods used (i.e. microwave, alkalization, ultrasounds and peroxydisulfate activated by ultrasounds), the activated peroxydisulfate disintegration resulted in the greatest DD 83% and the smallest median particle size of WAS. Particle size distribution of pretreated sludge, measured by DCS, was in a negative correlation with the DD, determined from soluble chemical oxygen demand (SCOD; determination coefficient of 0.995). Based on the obtained results, it may be concluded that the DCS analysis can approximate the WAS disintegration degree.

Occurrences of gastrointestinal parasites in fecal samples from domestic dogs in São Paulo, SP, Brazil.

Occurrences of gastrointestinal parasites were assessed in fecal samples from 3,099 dogs in the metropolitan region of São Paulo, SP, that were treated at the Veterinary Hospital of the University of São Paulo Veterinary School. The samples were analyzed using the flotation and centrifugal sedimentation methods. The results were compared with those from previous studies (at different times). The frequency of each parasite was correlated with the dogs' ages, breeds and gender, as well as the occurrences of diarrhea and the use of anthelmintics, by means of the chi-square or Fisher exact test. Partitioned chi-square tests were used to compare occurrences of each parasite and the times analyzed. Out of the total number of samples, 20.5% were positive and 16.1% (102/635) of these presented more than one genus of parasites. Ancylostoma spp. (7.1%) and Giardia spp. (5.5%) were the most frequent helminths and protozoa, respectively. Ancylostoma spp. was associated (p<0.05) with age (over one year), mixed breeds, sex (male) and no use of anthelmintics. Dogs under one year and mixed breeds were associated with occurrences of Toxocara canis; and younger dogs with Giardia spp., Cryptosporidium spp. and Cystoisospora spp. Giardia spp. were also associated with dogs with a defined breed (p<0.05). All the parasites analyzed presented lower incidence in the last period analyzed than in the previous periods.

Concordance between the zinc sulphate flotation and centrifugal sedimentation methods for the diagnosis of intestinal parasites

The diagnosis of intestinal parasitic infections depends on the parasite load, the specific gravity density of the parasite eggs, oocysts or cysts, and the density and viscosity of flotation or sedimentation medium where faeces are processed. To evaluate the concordance between zinc sulphate flotation and centrifugal sedimentation in the recovery of parasites in faecal samples of children. Faecal samples of 330 children from day care centers were evaluated by zinc sulphate flotation and centrifugal sedimentation techniques. The frequencies of detection of parasites by each method were determined and the agreement between the diagnostic techniques was evaluated using the kappa index, with 95% confidence intervals. The faecal flotation in zinc sulphate diagnosed significantly more cases of Trichuris trichiura infection when compared to centrifugal sedimentation (39/330; 11.8% vs. 13/330; 3.9%, p<0.001), with low diagnostic concordance between methods (kappa=0.264; 95% CI: 0.102-0.427). Moreover, all positive samples for Enterobius vermicularis eggs (n=5) and Strongyloides stercoralis larvae (n=3) were diagnosed only by zinc sulphate. No statistical differences were observed between methods for protozoa identification. The results showed that centrifugal flotation in zinc sulphate solution was significantly more likely to detect light helminths eggs such as those of T. trichiura and E. vermicularis in faeces than the centrifugal sedimentation process.

Measurement of cement’s particle size distribution by the buoyancy weighing-bar method

One of the important characteristics of cement quality is particle size distribution. There are several simple methods to measure the particle size distribution of cement based on the Stokes diameter, like Andreasen pipette method, sedimentation balance method, centrifugal sedimentation method, etc. A major disadvantages of these methods are they are time consuming process and require special skills. Particle size distribution also can be analyzed by using a different principle through microscopy, laser diffraction/scattering methods and Coulter counter method. Even these methods produce highly accurate results within a shorter time, however, the equipments are expensive. In the present study, it has developed a new method to overcome the problem. The method is the buoyancy weighing-bar method. This method is a simple and cost-effective. The principle of the buoyancy weighing-bar method that the density change in a suspension due to particle migration is measured by weighing buoyancy against a weighing–bar hung in the suspension, and the particle size distribution is calculated using the length of the weighing-bar and the time–course change in the the apparent mass of the weighing–bar. This apparatus consists of an analytical balance with a hook for underfloor weighing, and a weighing–bar, which is used to detect the density change in suspension. The result obtained show that the buoyancy weighing–bar method is suitable for measuring the particle size distribution of cement, and the result is comparable to that of determined by settling balance method.

PENENTUAN DISTRIBUSI UKURAN PARTIKEL TEPUNG TERIGU DENGAN MENGGUNAKAN METODE PENGAPUNGAN BATANG (BUOYANCY WEIGHING-BAR METHOD)

Particle size measurement of wheat flour is important in wheat flour industry. There are several methods have been used to measure particle size distribution (PSD) of wheat flour, such as Andreasen pipette method, sedimentation balance method, centrifugal sedimentation method. The disadvantages of these methods are that they are time consuming and require special skills. On the other hand, PSD can be analyzed using a different principle through laser diffraction/scattering methods, and coulter counter method. The laser diffraction/scattering and coulter counter methods produce highly accurate results within a shorter time, but the equipment is extremely expensive. Therefore, a simple and cost-effective new method to determine PSD is in high demand. In this study, we aim to develop a new method to measure the particle size distribution of wheat flour using a buoyancy weighing–bar method. In this method, the density change in a suspension due to particle migration (wheat flour) is measured by weighing buoyancy against a weighing–bar hung in the suspension (etanol/metanol), and the PSD is calculated using the length of the bar and the time–course change in the mass of the bar. This apparatus consists of an analytical balance with a hook for underfloor weighing, and a weighing–bar, which is used to detect the density change in suspension. The result obtained show that the PSD of wheat flour measured by the buoyancy weighing-bar method is comparable to that determined by settling balance method.

Prevalence of Gastrointestinal Parasites in Gaur (Bos gaurus) and Domestic Cattle at Interface Zones of the Nilgiri Hills, Tamil Nadu, India

Little is known about gastrointestinal parasite infections in wild ruminants. Faecal survey of parasitic prevalence plays an important role in wildlife management. The Wildlife interface regions, adjoining regions of forests serve as potential marker zones that serve to intermediate buffer zones that provide the viable ecology for the transit of various parasites between domestic and wild animals sharing the same landscape. Parasitic infections can cause disease and death in wild animals and can become a source of infection for domestic animals. Epidemiological studies are important to know about the status and transmission of these diseases. Parasitic diseases are best controlled by preventing the contact and parasite transmission between wild and domestic animals and by manipulating the factors involved in the disease transmission. The aim of this paper was to find out the prevalence of gastrointestinal parasites in gaur (bos gaurus) and domestic cattle at interface zones of the nilgiri hills. Qualitative examination of faecal samples from wild gaur (n=30) sharing ecosystem with domestic cattle (n=20) in the Nilgiri hills was done by Centrifugal sedimentation method and Floatation method. The prevalence was 63.3% and 80.0% in wild gaur and domestic cattle respectively with overall prevalence of 70.0%. The helminthes observed were trematodes (13.3%) include Fasciola sp. (3.3%), Amphistome sp. (6.7%) and Schistosoma sp. (3.3%), cestodes (20.0%) include Moniezia sp. nematodes (43.3%) include Toxocara sp. (6.7%), Strongyle sp. (23.3%), Oesophagostomum sp. (3.3%), Trichuris sp. (6.7%) and Mecistocirrus sp. (3.3%) and unsporulated Coccidia oocysts (13.3%) in wild gaur. It was concluded that, parasitic prevalence survey is vital in monitoring the impact on the health and maintenance of wild gaur population, and the prevalence of GI parasites recorded in the wild gaur and domestic cattle in the study areas shows the need to design and implement a control policy of helminth parasites in the Nilgiri hills.

Temporal-spatial patterns of intestinal parasites of the Hooded Crane (Grus monacha) wintering in lakes of the middle and lower Yangtze River floodplain

Parasites have adverse effects on the life and survival of many migratory waterbirds, especially birds on the endangered species list. Hooded Cranes are large migratory colonial waterbirds wintering in wetlands, which are prone to parasite infection, thus monitoring the diversity of parasites is important for sound wetland management and protection of this species. From November 2012 to April 2013, we collected 821 fresh faecal samples from the three lakes (Poyang, Caizi and Shengjin Lake) in the lower and middle Yangtze River floodplain, and detected with saturated brine floating and centrifugal sedimentation methods. Parasite eggs were quantified with a modified McMaster’s counting method. In this study, 11 species of parasites were discovered, i.e., two coccidium (Eimeria gruis, E. reichenowi), five nematodes (Capillaria sp., Strongyloides sp., Ascaridia sp., Trichostrongylus sp., Ancylostomatidae), three trematodes (Echinostoma sp., Echinochasmus sp., Fasciolopsis sp.) and one cestode (Hymenolepis sp.). About 57.7% of the faecal samples showed parasitic infection. All species of parasites were found at the three sites except Hymenolepis which was not found at Poyang Lake. While most samples were affected by only one or two species of parasites, infection by Eimeria spp. was the most common (53.1%). From One-Way ANOVA analysis of the three lakes, parasite species richness index (p = 0.656), diversity index (p = 0.598) and evenness index (p = 0.612) showed no significant difference. According to the statistical analysis of our data, there were no significant difference in parasite species richness index (p = 0.678) and evenness index (p = 0.238) between wintering periods, but a strong difference in diversity index (p < 0.05). Our study suggests that in the wintering Hooded Crane populations, parasite diversity is more sensitive to changes in the overwintering periods than to locations. This also indicates that with the limitations of migration distance, the parasites may not form the differentiation in Hooded Crane populations of the three lakes.

Comparison of the effects of different protocols on the particle size distribution of TiO2 dispersions

There is a need to standardize methods associated with the dispersion of nanomaterials in nano(eco)toxicological investigations. The first step toward this goal is to understand the degree of variability that exists in nanomaterial dispersions prepared by using different protocols. Using two case studies, the degree of variability in TiO2 nanomaterial dispersions was assessed by differential centrifugal sedimentation (DCS) methods. Case study 1 addresses the variability that arises from variations within one protocol, investigating the effects of dispersion aging, sonication exposure time, sonication in the presence/absence of an ice bath, material subsampling, particle concentration and having a pre-wetting step. Case study 2 addresses the variability between four different protocols developed through past research activities and projects. The results indicate that there is a large degree of variability (relative standard deviation (RSD) of mean particle diameter=26%) in the dispersion of TiO2 nanomaterials between the four different protocols studied and that several steps in a dispersion protocol are potential sources of variation, with final particle concentration being the most significant. The implication of this study is clear: for the purpose of data comparability, there is a need to provide the exact details of all steps involved in a dispersion protocol.

Acoustic wave in a suspension of magnetic nanoparticle with sodium oleate coating

The ultrasonic propagation in the water-based magnetic fluid with doubled layered surfactant shell was studied. The measurements were carried out both in the presence as well as in the absence of the external magnetic field. The thickness of the surfactant shell was evaluated by comparing the mean size of magnetic grain extracted from magnetization curve with the mean hydrodynamic diameter obtained from differential centrifugal sedimentation method. The thickness of surfactant shell was used to estimate volume fraction of the particle aggregates consisted of magnetite grain and surfactant layer. From the ultrasonic velocity measurements in the absence of the applied magnetic field, the adiabatic compressibility of the particle aggregates was determined. In the external magnetic field, the magnetic fluid studied in this article becomes acoustically anisotropic, i.e., velocity and attenuation of the ultrasonic wave depend on the angle between the wave vector and the direction of the magnetic field. The results of the ultrasonic measurements in the external magnetic field were compared with the hydrodynamic theory of Ovchinnikov and Sokolov (velocity) and with the internal chain dynamics model of Shliomis, Mond and Morozov (attenuation).