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Hymenolepis diminuta is a tapeworm commonly found worldwide in small rodents such as rats with occasional reports in other definitive hosts such as primates including chimpanzees and humans. It has not been reported in African green monkey (AGM, Chlorocebus sabaeus), and the parasite's molecular phenotype and phylogeny remain primitively sketchy. The aims of the current study were to determine if H. diminuta infected AGMs, to molecularly characterize H. diminuta and to review its infection in non-human primates. Feces of AGMs were examined visually for adult helminths and microscopically for eggs using centrifugation flotation. Total DNA extracted from eggs was amplified by PCR followed by DNA sequencing of targeted sequences of nuclear rRNA + internal transcribed spacers (ITS) and mitochondrial cox1. Phylogenetic analyses were performed. The DNA sequences of both nuclear rRNA + ITS and mitochondrial cox1 showed more than 98% and 99% identity to the known sequences respectively. Hymenolepis diminuta has been reported in various non-human primates with the highest prevalence of 38.5% in the white-headed capuchin monkey. The study presented here confirms that this tapeworm is capable of infecting various species of non-human primates with the first report of infections in AGM. Phylogenetic analyses of rRNA + ITS and mitochondrial cox1 demonstrated three separated clades I, II and III with the newly described AGM1 isolate belonging to the clade I. Whether these differences are at species level remains to be confirmed. [ABSTRACT FROM AUTHOR]

Background: Human pediculosis is caused by hematophagous lice, which are transmitted between individuals via direct and/or indirect contact. Despite the public health importance of louse infestation, information concerning the global burden of pediculosis and the epidemiological landscape of louse-borne diseases is limited. The aim of this review was to summarize the biology, epidemiology, diagnosis, and control of lice infestation in humans. We also discussed the latest advances in molecular taxonomy and molecular genetics of lice. Methods: We searched five electronic bibliographic databases (PubMed, ScienceDirect, CNKI, VIP Chinese Journal Database, and Wanfang Data) and followed a standard approach for conducting scoping reviews to identify studies on various aspects of human lice. Relevant information reported in the identified studies were collated, categorized, and summarized. Results: A total of 282 studies were eligible for the final review. Human pediculosis remains a public health issue affecting millions of people worldwide. Emerging evidence suggests that head lice and body lice should be considered conspecific, with different genotypes and ecotypes. Phylogenetic analysis based on mitochondrial (mt) cytb gene sequences identified six distinct clades of lice worldwide. In addition to the direct effect on human health, lice can serve as vectors of disease-causing pathogens. The use of insecticides plays a crucial role in the treatment and prevention of louse infestation. Genome sequencing has advanced our knowledge of the genetic structure and evolutionary biology of human lice. Conclusions: Human pediculosis is a public health problem affecting millions of people worldwide, particularly in developing countries. More progress can be made if emphasis is placed on the use of emerging omics technologies to elucidate the mechanisms that underpin the physiological, ecological, and evolutionary aspects of lice. [ABSTRACT FROM AUTHOR]

Background: Toxoplasma gondii is an obligate parasite of all warm-blooded animals around the globe. Once infecting a cell, it manipulates the host’s DNA damage response that is yet to be elucidated. The objectives of the present study were three-fold: (i) to assess DNA damages in T. gondii-infected cells in vitro; (ii) to ascertain causes of DNA damage in T. gondii-infected cells; and (iii) to investigate activation of DNA damage responses during T. gondii infection. Methods: HeLa, Vero and HEK293 cells were infected with T. gondii at a multiplicity of infection (MOI) of 10:1. Infected cells were analyzed for a biomarker of DNA double-strand breaks (DSBs) γH2AX at 10 h, 20 h or 30 h post-infection using both western blot and immunofluorescence assay. Reactive oxygen species (ROS) levels were measured using 2′,7′-dichlorodihydrofluorescein diacetate (H2DCFDA), and ROS-induced DNA damage was inhibited by a ROS inhibitor N-acetylcysteine (NAC). Lastly, DNA damage responses were evaluated by detecting the active form of ataxia telangiectasia mutated/checkpoint kinase 2 (ATM/CHK2) by western blot. Results: γH2AX levels in the infected HeLa cells were significantly increased over time during T. gondii infection compared to uninfected cells. NAC treatment greatly reduced ROS and concomitantly diminished γH2AX in host cells. The phosphorylated ATM/CHK2 were elevated in T. gondii-infected cells. Conclusions: Toxoplasma gondii infection triggered DNA DSBs with ROS as a major player in host cells in vitro. It also activated DNA damage response pathway ATM/CHK2. Toxoplasma gondii manages to keep a balance between survival and apoptosis of its host cells for the benefit of its own survival. [ABSTRACT FROM AUTHOR]

• Acoustic cavitation behavior in microchannel was systematically investigated. • The critical microchannel size to eliminate confinement effect was obtained. • Acoustic cavitation was promoted in liquid with low viscosity and tension. • An operation guideline for ultrasound-assisted nitration process was established. Experimental studies on acoustic cavitation and ultrasound-assisted nitration reaction were systematically investigated in two laboratory-built ultrasonic microreactors by tuning the microchannel dimension, solvent properties and temperature. Under ultrasound irradiation, acoustic cavitation microbubbles were generated and underwent violent oscillation in microchannel. With the decrease of channel size, acoustic cavitation was largely confined, and channel size 1 × 1 mm2 was recognized as the critical size to eliminate the confinement effect. Acoustic cavitation was also highly dependent on the properties of sonicated liquids. The onset of surface wave oscillation on gas bubble was obviously promoted with decreasing solvent viscosity and surface tension. Additionally, ultrasound-assisted nitration process of toluene was studied in a temperature-controlled ultrasonic microreactor. The effects of channel size as well as liquid properties on ultrasound intensification agreed well with the finding in cavitation research. Under ultrasound power 50 W, toluene conversion was enhanced by 9.9%–36.3% utilizing 50 vol.% ethylene glycol aqueous solution as ultrasound propagation medium, exhibiting ultrasound applicability on intensifying fast reaction processes in microreactors. [ABSTRACT FROM AUTHOR]

• The effect of liquid viscosity (0.89–45.6 mPa·s) on Taylor flow is investigated. • Higher viscosity leads to more stable instantaneous flow rate during formation stage. • The film thickness at short planes are much larger than predicted in literature. • A distinct bubble shape with sharpened rear cap is observed. • A correlation representing the effect of recirculation on pressure drop is proposed. Characteristics of gas-liquid Taylor flow with different liquid viscosities are investigated in a rectangular microchannel, aiming at providing knowledge and aid in the design of processes involving viscous fluid, such as polymers and ionic liquids. The effect of liquid viscosity on the bubble formation dynamic, film thickness, bubble velocity, and pressure drop is investigated. The results reveal a specific viscous effect compared to those in square or circular channels. For the same capillary number, both the liquid film thickness at the corners and at the short planes are much larger than in square channels. New correlations are proposed for predicting the film thickness in the rectangular channel. The bubble shape sheared by the liquid phase is also distinct from literature observations that a smaller radius occurs at the rear cap. For the conditions studied (0.00065 < Ca < 0.0525), increasing the viscosity leads to an increase in the instantaneous flow rate, and also an later shift from filling stage to squeezing stage. As the bubble formation is driven by both squeezing pressure and shearing force, the bubble/slug length is affected by both capillary number and flow rate ratio. The recirculation inside liquid slugs is found to play an important role in the pressure drop, which can be well described by an empirical correlation including dimensionless liquid slug length and capillary number. [ABSTRACT FROM AUTHOR]

Detection of cardiac troponin I (cTnI) plays a critical role in diagnosing acute myocardial infarction (AMI). In this report, a new kind of spherical AuPt@Fe x O y core@shell nanoparticles (termed as AuPt@Fe x O y NPs) were one-pot synthesized by a redox interaction-engaged strategy (RIES) without the addition of any surfactants or reducing agents. The as-synthesized AuPt@Fe x O y NPs not only retain the plasmonic activity of gold nanoparticles (AuNPs), but also possess excellent catalytic activities of platinum nanoparticles (PtNPs) and Fe x O y nanoclusters. The features of AuPt@Fe x O y NPs enable greatly enhance the colorimetric detection sensitivity of lateral flow immunoassay (LFIA) through integrating AuPt@Fe x O y NPs labeling procedure and catalyzing oxidation of chromogenic substrate 3,3',5,5'-tetramethylbenzidine (TMB) signal amplification strategy. The as-developed colorimetric LFIA (termed as AuPt@Fe x O y -LFIA) exhibits the limit of detection (LOD) as 26.0 pg mL−1 cTnI under the TMB signal amplification mode. In particular, the detection results of cTnI in 40 clinical seral samples by AuPt@Fe x O y -LFIA are correlated well with those of cTnI in the same samples by commercial enzyme-linked immunosorbent assay (ELISA) detection kit (R2 = 0.97, slope = 1), demonstrating the highly reliable analytical performance and good application prospect of AuPt@Fe x O y -LFIA. [Display omitted] [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Olefin/paraffin separation processes with AgNO 3 solutions are investigated. • The evolution of absorption fraction and k L a along microchannel was investigated. • The evolution of bubble size along channel length was investigated. • The effect of ultrasound was investigated, achieving significant intensification. Abstract Ultrasound is an effective method to intensify gas-liquid processes as the oscillation energy is easily focused at the gas-liquid interface, which can induce strong interface oscillation and acoustic streaming. The combination of ultrasound and microreactor provides ideal control over the ultrasound field, making the energy efficiently utilized. In this study, characteristics of chemical absorption of C 2 H 4 from the mixture of C 2 H 6 /C 2 H 4 into AgNO 3 solutions under Taylor flow are investigated in a high-power ultrasonic microreactor. The effect of ultrasound on the bubble size reduction, absorption and mass transfer coefficient is presented and discussed. It is demonstrated that very large mass transfer coefficient with k L a and k L in the range of 7–42 s−1 and 0.00169–0.0225 m s−1 respectively are obtained, presenting significant intensification compared to absorption without ultrasound in the same reactor. [ABSTRACT FROM AUTHOR]

Microreaction technology is an important technology for process intensification and high efficient chemical synthesis. The use of ionic liquids (ILs) as novel reaction media is another rapidly developing orientation for process intensification considering their strong dissolubility, low vapor pressure and adaptable physicochemical properties. The combination of the two technologies has been emerging fast in various applications, due to the ability to intensify the utility of ILs in microreactors. This review presents a summary of the recent progress on the transport and reaction processes with ILs in microreactors. A typical characteristic of ILs is their higher viscosity, so the effects of fluid viscosity on the hydrodynamics and mass transfer are highlighted. In addition, new correlations considering both shear and inertial forces are proposed to predict the flow regime transitions in a wide range of fluid viscosity. With respect to mass transfer, the unit cell model for Taylor flow is modified to represent the effect of viscosity on flow topology inside droplets/slugs. [ABSTRACT FROM AUTHOR]

The synergistic effects of gas agitation and ultrasound on mass transfer between immiscible liquids were investigated in an in-house made ultrasonic microreactor. With the introduction of inert gas (N 2 ), a three-phase slug flow with slug bubbles either dispersed in continuous aqueous phase or encapsulated in oil plugs was observed. Under ultrasound irradiation, slug bubbles underwent surface wave oscillation and induced agitation in microchannel. In addition, microbubbles were generated by acoustic cavitation, oscillating intensely and resulting in the formation of O/W emulsion. Bubble oscillation (i.e., slug bubbles and microbubbles) as well as emulsification promoted liquid-liquid mass transfer significantly. Extraction of vanillin from aqueous solution to toluene was employed to demonstrate the mass transfer enhancement. Compared with silent operation, both mass transfer coefficient and extraction efficiency were largely improved by the combined use of gas agitation and ultrasound. With gas flow velocity being 0.005–0.083 m/s at fixed ultrasound power of 30 W, the overall mass transfer coefficients ranged from 0.047 s −1 to 0.429 s −1 , which was 2.33–17.20 times larger than the corresponding liquid-liquid two-phase process without ultrasound irradiation. [ABSTRACT FROM AUTHOR]

• The mixing of antisolvent process was intensified by combining power ultrasound and microreactor. • Transient cavitation become easier to initiate in antisolvent process compared to pure liquids. • Two distinct cavitation patterns of bubbles group were observed, bubble array and bubble cluster. • Mixing under the cluster pattern was significantly better than that under the array pattern. • The prepared mini-emulsion exhibited good performance in droplet size, size distribution and stability. An approach combining power ultrasound and microchannel was proposed to promote the mixing of miscible fluid in antisolvent processes. Cavitation microbubbles evolved and oscillated during ultrasound actuation, with antisolvent processes facilitating easier initiation of transient cavitation compared to pure liquids. Interaction among microbubbles led to two distinct group patterns, bubble array and bubble cluster, which greatly impacted mixing. Both patterns could increase mixing efficiency by at least one order of magnitude compared to microfluidic devices and previously-studied ultrasonic microreactors in the literature. Mixing time under the array pattern ranged from 100 to 250 ms, while that under the cluster pattern ranged from 50 to 200 ms. The approach produced high-quality mini-emulsion with unimodal size in the range of 180–290 nm for a model system (acetone-soybean oil–water). [ABSTRACT FROM AUTHOR]

Abstract: The heat transfer performance and energy consumption of CO2 desorption from rich N‐methyldiethanolamine (MDEA) solution were determined experimentally in a straight microchannel reactor. Nucleate boiling was found to be the dominant heat transfer mechanism in this experiment. The heat transfer coefficients were strongly dependent on the heat flux. The solution flow rate was the most influential factor on the heat flux, followed by desorption temperature, MDEA concentration, and CO2 loading. In addition, an empirical correlation was proposed to predict the experimental heat transfer coefficients. [ABSTRACT FROM AUTHOR]

The present work focuses on the hydrodynamics variation and mass transfer characteristics of Taylor flow along long serpentine microchannels with a square cross-section. The volumetric mass transfer coefficient ( k L a ) is regarded as the transient change value to characterize the gas-liquid mass transfer process of CO 2 in water. All experimental data of Taylor bubble are obtained from 1000 continuously captured images. An online high-speed imaging method and the unit cell model are adopted in this study. The effects of gas and liquid flow rates, together with microchannel geometry are investigated on Taylor bubble characteristics in terms of length, velocity and the mass transfer performance. Taylor bubble length shrinks and subsequently plateaus out along the flow direction from the T-junction, resulting in the decrease in Taylor bubble velocity. k L a in a unit cell gradually decreases along the serpentine microchannel, and increases as the channel cross-sectional area decreases. As the gas flow rate increases under a given liquid flow rate, a critical point is found for the evolution of k L a and k L (that is the liquid phase mass transfer coefficient). The results indicate that the contribution of the circulation in the liquid slug to k L is dominant before the critical point compared to the leakage flow in the liquid film. All these findings in this work give important information to understand the dynamic change in gas-liquid Taylor flow mass transfer within microchannels. They will serve as basis for designing and optimizing gas-liquid multiphase microreactors in the future. [ABSTRACT FROM AUTHOR]

This paper presents a study on the hydrodynamics and mass transfer performance of absorption of CO 2 into deionized water and DEA solutions in a microreactor under elevated pressures up to 4.0 MPa. It is demonstrated that increasing gas density (system pressure) leads to increased pressure drop. Considering such effect, a modified Lockhart-Martinelli model is developed, showing good prediction over the two-phase pressure drop. For the mass transfer performance, parametric studies by varying system pressure, temperature of feeding fluids, molar ratio of DEA/CO 2 and CO 2 -loaded DEA solutions are presented. Two empirical correlations based on the power consumption are developed for the prediction of mass transfer coefficients in physical and chemical absorptions, respectively. The results suggest significant intensification is achieved in the microreactor. Besides, dramatic increase of CO 2 loading in the rich absorbents is also obtained, which is very attractive for solvent regeneration. The findings in this paper can serve as guidance in the design of processes with high-pressure operations, such as natural gas purification or biogas recovery. [ABSTRACT FROM AUTHOR]

The nitration process of 2-ethylhexanol (2-EH) with mixed acid was studied in different capillary microreactors. The conversion of 2-EH and selectivity to 2-ethylhexyl nitrate (EHN) were investigated by varying reaction temperature, molar ratio of nitrate to 2-EH, residence time and water content in mixed acid. Under optimized conditions, the conversion of 2-EH and selectivity to EHN could be up to 99% in less than 10 seconds, indicating great potential of microreactors in process intensification. Moreover, with an assumption of homogeneous reaction, a kinetic model based on first order kinetics for nitric acid and 2-EH was proposed to determine both the apparent and intrinsic reaction kinetics. By taking into account the activity of solutes that depend on the acidity (M c ), the intrinsic kinetic was obtained, which is independent of the sulfuric acid concentration. The reaction model can well predict the conversion of 2-EH. [ABSTRACT FROM AUTHOR]

CO 2 desorption from N -methyldiethanolamine (MDEA) rich solutions was investigated experimentally in a highly efficient microchannel reactor. The effects of various parameters including MDEA concentration, desorption temperature, solution flow rate and CO 2 loading on the CO 2 desorption rate were studied. It was found that the CO 2 desorption rate was most sensitive to the desorption temperature. The CO 2 desorption almost reached equilibrium when the solution residence time was about 7 s, indicating the advantages of using microchannel reactors for rapid CO 2 desorption. The value of k L a was in the range of 0.36–2.68 s −1 in the experiments, which is comparable to that of absorption in microchannels and much larger than in conventional equipment. For the design of micro-desorbers, empirical correlations were proposed to predict the mass transfer coefficient with good prediction performance. [ABSTRACT FROM AUTHOR]

• Evolution process of oscillation of cavitation bubble with ultrasound was analyzed. • Acoustic cavitation was promoted at low frequency in low surface tension liquid. • A semi-experimental equation was proposed to predict the cavitation mode. • The mass transfer behavior was compared with other reactors using a power law model. • An operation guideline for ultrasound-assisted extraction process was established. Experimental studies on acoustic cavitation and ultrasound-assisted extraction process were systematically investigated in the laboratory-built ultrasonic microreactors. The cavitation evolution process of microbubble after ultrasound exposure was first analyzed, finding that surface tension plays a vital role on bubble oscillation. The effects of fluid property as well as ultrasound frequency on cavitation activity were then investigated, and a discriminating criterion was established on the basis of experimental data, which can well predict the bubble cavitation mode. In addition to acoustic cavitation, the effects of varying parameters, e.g., ultrasound frequency, input mode, on ultrasound-assisted extraction process were also investigated, the result of which, correlates well with the cavitation research from a meso-scale perspective. It was found that the overall mass transfer coefficients are solely related to the specific energy dissipation rate under all circumstances. At specific energy dissipation rate 3–675 W/kg, the overall mass transfer coefficients were measured to be 0.01–0.24 s−1, being comparable to that of reciprocating plate column and far high than the passive microreactor. [ABSTRACT FROM AUTHOR]

Flow and mass transfer of gas-liquid slug flow under elevated pressures up to 3.0 MPa in a microchannel are investigated with CO 2 -water system. The results show that the ratio of the initial bubble length to the unit cell length is linear with the injection gas volume fraction under each pressure condition, but the slope decreases with an increase in the system pressure. The mass transfer coefficients are calculated with a unit cell model based on the dissolution rate of gas bubbles. Increasing pressure leads to larger mass transfer coefficients, as well as higher amount of gas absorption during the bubble formation. But the fraction of gas absorption during the bubble formation stage is only about 1.5~4.0% of feeding gas. For the bubble dissolution in the main channel, the dissolution rates at different flow rates differ very little for short contact distances from the T-junction, whereas the balance limitation of dissolution at large contact distances only depends on the amount of liquid in a unit cell. [ABSTRACT FROM AUTHOR]

The combination of ultrasound and microreactor is an emerging and promising area, but the report of designing high-power ultrasonic microreactor (USMR) is still limited. This work presents a robust, high-power and highly efficient USMR by directly coupling a microreactor plate with a Langevin-type transducer. The USMR is designed as a longitudinal half wavelength resonator, for which the antinode plane of the highest sound intensity is located at the microreactor. According to one dimension design theory, numerical simulation and impedance analysis, a USMR with a maximum power of 100 W and a resonance frequency of 20 kHz was built. The strong and uniform sound field in the USMR was then applied to intensify gas–liquid mass transfer of slug flow in a microfluidic channel. Non-inertial cavitation with multiple surface wave oscillation was excited on the slug bubbles, enhancing the overall mass transfer coefficient by 3.3–5.7 times. [ABSTRACT FROM AUTHOR]

Abstract: Physical absorption of CO2 bubbles under slug flow has been studied in a T-junction microchannel. Based on the absorption rate of gas bubbles, an online photographic method is proposed to determine the mass transfer coefficients. Validity of this method is verified by evaluating bubble expansion due to pressure drop and by comparing the results with literature. The effect of fluid properties on the mass transfer has also been studied with ethanol solutions, which shows that mass transfer coefficient increases with the increase of ethanol concentration. The amount of gas absorbed during the bubble formation process has been measured to be about 2–10% of the inlet gas phase, and is found to linearly scale with the maximum mass transfer rate. For each fluid system, the initial dissolution rates of bubbles differ very little for short contact distance, whereas, the final amount of dissolution only depends on the residence time. [Copyright &y& Elsevier]

The development of highly efficient processes for the cycloaddition of CO2 with epoxides to produce five-membered cyclic carbonates is a very attractive topic. In this work, the cycloaddition of propylene oxide (PO) and CO2 to give propylene carbonate (PC) is studied in a microreactor using a HETBAB ionic liquid catalyst. The microreactor performance is evaluated by studying the effects of different operating conditions, including reaction temperature, operating pressure, residence time, molar ratio of CO2/PO, and the catalyst concentration in PO. The process characteristics of the reaction concerning the gas–liquid mass transfer and the intrinsic kinetics perspectives are discussed. The results show that the residence time can be dramatically reduced from several hours in a conventional stirred reactor to about 10 s in a microreactor. The yield of PC at 3.5 MPa can reach 99.8% at a residence time of 14 s. The turnover frequency (TOF) value varies in the range of 3000 to 14 000 h−1 compared to 60 h−1 in the conventional stirred reactor. The space time yield (STY) or the overall reaction rate ranges from 650 to 4500 gprod. (gcat. h)−1, which is much larger than the value [ca. 19 gprod. (gcat. h)−1] for the conventional stirred reactor. To some extent, the present study has also demonstrated the concept of ‘Novel Process Windows’. [ABSTRACT FROM AUTHOR]

Abstract: The main purpose of this mini-review is to provide information on opportunistic human infections caused by Tritrichomonas spp. Rare cases of human trichomoniasis, including fatal meningoencephalitis and peritonitis, have been reported exclusively in immunosuppressed or immunocompromised individuals, suggesting the protozoa are human opportunistic pathogens. These infections are readily diagnosed by the characteristic morphology of the protozoa. Species identification is augmented by testing with molecular methods, such as PCR and DNA sequencing. Risk factors for infection and treatment are also discussed. [Copyright &y& Elsevier]

Sucking lice are obligate ectoparasites of mammalian hosts, causing serious public health problems and economic losses worldwide. It is well known that sucking lice have fragmented mitochondrial (mt) genomes, but many remain undetermined. To better understand patterns of mt genome fragmentation in the sucking lice, we sequenced the mt genome of the buffalo louse Haematopinus tuberculatus using next-generation sequencing (NGS). The mt genome of H. tuberculatus has ten circular minichromosomes containing a total of 37 genes. Each minichromosome is 2.9–5.0 kb long and carries one to eight genes plus one large non-coding region. The number of mt minichromosomes of H. tuberculatus (ten) is different from those of congeneric species (horse louse H. asini, domestic pig louse H. suis and wild pig louse H. apri) and other sucking lice. Two events (gene translocation and merger of mt minichromosome) are observed in Haematopinus. Compared to other studies, our phylogeny generated from mt genome datasets showed a different topology, suggesting that inclusion of data other than mt genomes would be required to resolve phylogeny of sucking lice. To our knowledge, this is the first report of a ten mt minichromosomes genome in sucking lice, which opens a new outlook into unexplored mt genome fragmentation patterns in sucking lice. [ABSTRACT FROM AUTHOR]

Abstract: Infections of domesticated dogs by a worldwide parasitic nematode Filaroides osleri (Oslerus osleri) lead to verminous tracheobronchitis that are often misdiagnosed clinically as kennel cough, due to infection with the bacterium Bordetella bronchiseptica. Diagnosis of two canine cases in Wyoming, USA prompted a search of the literature of canid infections in North America. Infections of domestic dogs are reported in nine US states and four Canadian provinces. Dogs of multiple breeds and both sexes were infected. Most were two years old or younger at diagnosis. Anthelmintic treatments were effective in relieving clinical symptoms, as well as causing resolution of tracheobronchial nodules. Other canid species, including coyotes (Canis latrans) and wolves (Canis lupus), have been infected across North America with a prevalence of 23% and 4%, respectively. Infection with F. osleri should be included in the differential diagnosis of infectious tracheobronchitis of dogs. It can be confirmed most readily by endoscopic detection of distinctive submucosal parasite-filled nodules, combined with histological examination of endoscopic biopsies. [Copyright &y& Elsevier]

Abstract: The Leishmania spp. protozoa have an abundant surface metalloprotease called MSP (major surface protease), which in Leishmania chagasi is encoded by three distinct gene classes (MSPS, MSPL, MSPC). Although MSP has been characterized primarily in extracellular promastigotes, it also facilitates survival of intracellular amastigotes. Promastigotes express MSPS, MSPL, and two forms of MSPC RNAs, whereas amastigotes express only MSPL RNA and one MSPC transcript. We confirmed the presence of MSPC protein in both promastigotes and amastigotes by liquid chromatography–tandem mass spectrometry (LC–MS/MS). More than 10 MSP isoforms were visualized in both amastigotes and promastigotes using two-dimensional immunoblots, but amastigote MSPs migrated at a more acidic pI. Promastigote MSPs were N-glycosylated, whereas most amastigote MSPs were not. Immuno-electron microscopy showed that two-thirds of the promastigote MSP is distributed along the cell surface. In contrast, most amastigote MSP localized at the flagellar pocket, the major site of leishmania endocytosis/exocytosis. Biochemical analyses indicated that most amastigote MSP is soluble in the cytosol, vesicles or organelles, whereas most promastigote MSP is membrane-associated and GPI anchored. Activity gels and immunoblots confirmed the presence of a novel proteolytically active amastigote MSP of higher Mr than the promastigote MSPs. Furthermore, promastigote MSP is shed extracellularly whereas MSP is not shed from axenic amastigotes. We conclude that amastigotes and promastigotes both express multiple MSP isoforms, but these MSPs differ biochemically and localize differently in the two parasite stages. We hypothesize that MSP plays different roles in the extracellular versus intracellular forms of Leishmania spp. [Copyright &y& Elsevier]

Abstract: Homogenous metacyclic promastigotes of Leishmania chagasi were isolated by buoyant density from in vitro heterogeneous cultures and used for biochemical characterization of isoforms of the major surface protease (MSP). Compared to stationary phase promastigotes, metacyclic cells had three times more MSP, produced 3-fold higher parasite loads in a mouse model in vivo, and were more resistant to complement-mediated lysis in vitro. These metacyclic L. chagasi expressed both the virulence-associated 59-kDa, and the constitutively expressed 63-kDa, isoforms of MSP. [Copyright &y& Elsevier]

Abstract: Trypanosomatid protozoa lack consensus promoters for RNA polymerase (RNAP) II. However, the artificial insertion of the T7 promoter (PT7) and the tetracycline repressor into Trypanosoma brucei cell lines expressing T7RNAP allows PT7-driven gene expression to be tetracycline-inducible. These cell lines provide a molecular tool to address protein function by several recombinant approaches. We describe here the development of an analogous Leishmania chagasi cell line bearing the genes for exogenous T7RNAP and the tetracycline repressor inserted in the multi-gene α-tubulin locus. A plasmid construct with PT7 and the tetracycline operator upstream of a reporter gene, when introduced into this cell line as episomal plasmids or chromosomal insertion into the non-coding strand of an 18SrRNA gene, resulted in tetracycline-inducible expression of the reporter as much as 16- and 150-fold, respectively. The reporter was under a much tighter control when chromosomally inserted than extra-chromosomally born. Furthermore, PT7 augmented the reporter’s expression 2-fold more in comparison to PT7-less constructs. This cell line is the first Leishmania spp. that allows the exogenous T7RNAP-driven gene expression to be tetracycline-inducible; and may provide a useful tool for addressing protein function by manipulating expression levels of Leishmania endogenous genes. [Copyright &y& Elsevier]

Abstract: Major surface protease (MSP) facilitates Leishmania promastigote evasion of complement-mediated lysis in the mammalian host and enhances host macrophage phagocytosis of the promastigotes. We previously showed that the steady-state abundance of MSP protein increases 14-fold during in vitro cultivation of L. chagasi promastigotes from logarithmic to stationary phase, despite the fact that the total amount of MSP mRNA does not increase. Furthermore, 10 major MSP isoforms are differentially expressed in different promastigote growth phases, and attenuation of parasites by long-term in vitro cultivation influences MSP isoform expression. Herein, we report that although about two-thirds of newly synthesized MSP becomes surface localized, the rest of the MSP does not reach the promastigote surface. This internal MSP is stable without detectable decrease in abundance up to 6 days after biosynthesis. Furthermore, surface-localized MSP is released at different rates from logarithmic and stationary phase virulent Leishmania promastigotes. These data are consistent with the hypothesis that the major mechanism regulating MSP abundance is the rate of loss of surface-localized MSP from the promastigote surface, and that internally localized MSP is very stable. [Copyright &y& Elsevier]

The major surface protease (MSP or GP63) of the Leishmania spp. protozoa facilitates parasite evasion of complement-mediated killing, phagocytosis by macrophages, and intracellular survival in macrophage phagolysosomes. Immunoblots of several Leishmania species have shown there are distinct MSP isoforms, but the biochemical bases for these differences are unknown. Northern blots show that transcripts of the three tandem gene classes encoding Leishmania chagasi MSP (MSPS, MSPL, MSPC) are differentially expressed during parasite growth in vitro. Cell-associated MSPs increase in abundance during growth, correlating directly with parasite virulence. We examined whether distinct products of these >18 MSP genes are either differentially expressed or differentially processed during parasite growth. Two-dimensional gel electrophoresis and immunoblots delineated more than 10 MSP isoforms in stationary phase L. chagasi, distributed between pIs of 5.2–6.1 and masses of 58–63 kDa. Post-translational modifications including N-glycosylation, GPI anchor addition and phosphorylation did not account for all differences among the isoforms. MALDI-TOF mass spectrometry demonstrated that at least some L. chagasi MSPs were the products of different MSP genes. One isoform was not available for surface biotinylation, suggesting it could be located internally. Parasites in logarithmic growth expressed only four MSP isoforms, and an attenuated strain of L. chagasi (L5) did not express one of the MSP classes (MSPS). These data demonstrate that the products of individual MSP genes are differentially expressed during Leishmania development. We hypothesize they may play different roles during parasite migration through its two hosts. [Copyright &y& Elsevier]

Leishmania sp. are digenetic protozoa that cause an estimated 1.5–2 million new cases of leishmaniasis per year worldwide. Among the molecular factors that contribute to Leishmania sp. virulence and pathogenesis is the major surface protease, alternately called MSP, GP63, leishmanolysin, EC3.4.24.36, and PSP, which is the most abundant surface protein of leishmania promastigotes. Recent studies using gene knockout, antisense RNA and overexpression mutants have demonstrated a role for MSP in resistance of promastigotes to complement-mediated lysis and either a direct or indirect role in receptor-mediated uptake of leishmania. The MSP gene clusters in different Leishmania sp. include multiple distinct MSPs that tend to fall into three classes, which can be distinguished by their sequences and by their differential expression in parasite life stages. Regulated expression of MSP class gene products during the parasite life cycle occurs at several levels involving both mRNA and protein metabolism. In this review we summarize advances in MSP research over the past decade, including organization of the gene families, crystal structure of the protein, regulation of mRNA and protein expression, biosynthesis and possible functions. The MSPs exquisitely demonstrate the multiple levels of post-transcriptional gene regulation that occur in Leishmania sp. and other trypanosomatid protozoa. [Copyright &y& Elsevier]

The intestine of Haemonchus contortus is hypersensitive to the effects of the anthelmintic fenbendazole (FBZ). The effects are postulated to stem from disruption of microtubules and interference with apical secretory vesicle transport, followed by release of digestive enzymes into the intestinal cell cytoplasm. Here, FBZ caused marker proteins for both apical (pepsinogen-like protease, PEP-1) and basal (cystatin-like protein) protein compartments to became homogeneously distributed in the cytoplasm of H. contortus intestinal cells. The observations with PEP-1 support the hypothesis that release of hydrolytic enzymes into the intestinal cell cytoplasm contributes to the mechanism of benzimidazole efficacy. A benzimidazole resistant isolate of H. contortus expressed type 1 and 2 intestinal β-tubulin transcripts that would encode predominately tyr200 and phe200 variants, respectively. This isolate was resistant to the known intestinal cell alterations induced by FBZ treatment in the susceptible isolate, including inhibition of apical vesicle transport. These results implicate type 1 β-tubulin in mediating apical vesicle transport in intestinal cells and suggest that the tyr200 variant is a determinant of FBZ resistance in intestinal cells. In contrast, the basal protein compartment demonstrated sensitivity to FBZ treatment in these otherwise “resistant” worms. Hence, distinct FBZ-sensitive components appear to be involved in distributing intestinal proteins into the described apical and basal compartments of normal worms. [Copyright &y& Elsevier]

The protozoan Leishmania chagasi expresses a surface metalloprotease, GP63, whose abundance increases 14-fold as parasites grow from logarithmic to stationary phase. L. chagasi GP63 is encoded by three classes of MSP genes that are differentially expressed during parasite growth. Using metabolic labeling and immunoprecipitation, we found L. chagasi GP63 first appeared as a 66-kDa band that was replaced by a 63-kDa protein. This pattern also occurred in transfected L. donovani harboring detectable products of only one MSP gene, suggesting a precursor–product relationship. The half-life of GP63 increased from 29 h in logarithmic phase to >72 h in stationary phase promastigotes. GP63 loss from the cell was complemented by the appearance of a 63-kDa GP63 in extracellular medium in both membrane-associated and -free forms. Calculations suggested that the long and lengthening T1/2 of cell-associated GP63 accounts in part for its progressive accumulation in the cell during promastigote growth. The current findings add yet another level of complexity to post-transcriptionally regulated expression of an abundant surface molecule in a trypanosomatid protozoan. [Copyright &y& Elsevier]

• The emulsification mechanism behind high-speed shearing was uncovered. • The effect of ultrasound and high-speed shearing on emulsification was studied. • The effect of recycling flow on reducing emulsion size was investigated. • A novel hybrid frequency strategy was proposed to produce nano-emulsion. The study first investigated the effects of individual ultrasound and high-speed shearing on emulsification, both obtaining emulsions with average sizes of approximately 1 μm. Subsequently, a combined strategy to utilize shearing instrument producing coarse emulsion for ultrasonic microreactor was proposed. Immiscible liquids were drawn into the stirring chamber by rotating paddles, where they underwent strong shearing and thorough mixing. The pre-mixed liquids were introduced into microchannel and subjected to further processing by oscillating cavitation bubbles. Through optimization of experimental parameters such as residence time and recycle ratio, the average emulsion size was significantly reduced to 522 nm. Finally, a dual-frequency strategy using ultrasound frequencies of 20 and 40 kHz consecutively further reduced the emulsion size to 307 nm. In comparison with conventional sonoreactors and high-pressure homogenizers, this dual-frequency approach demonstrated superior emulsification performance with less surfactant addition and energy input, indicating its high applicability on continuous emulsification process with proper design and optimization. [Display omitted] [ABSTRACT FROM AUTHOR]

• Clogging of microchannel was investigated with NaCl salting-out process. • The respective anti-clogging effect of ultrasound and segmented flow was compared. • A novel strategy utilizing ultrasound-driven slug dredge microchannel was proposed. • Three oscillating slug-induced dredging modes was proposed. • An efficient aspirin recrystallization process was realized. A novel anti-clogging strategy by combining ultrasound and segmented flow was proposed and successfully applied to continuous crystallization process. The individual anti-clogging effect of ultrasound and segmented flow was first investigated, finding that both strategies only slow down the fouling process, but not capable of breaking the clogged solid sediment. As for the combining strategy, segmented slug/bubble was driven to oscillate intensely with ultrasound and dredge the fouled microchannel through three different mechanisms. Not only the long-term operation of microreactor system was guaranteed, but also the necessary energy input was reduced by 1–2 orders of magnitude compared to individual ultrasound. Finally, the ultrasound-driven oscillating slug/bubble was utilized for recrystallization of aspirin. Under E v 0.54–2.60 J/mL, a product yield of 53 %-72 % (equilibrium yield 72 %) was obtained with aspirin average size in the range of 7.84–32.01 μm. The synergistic strategy can be well generalized to various crystallization process once properly designed. [ABSTRACT FROM AUTHOR]

Background: Fleas (Insecta: Siphonaptera) are obligatory hematophagous ectoparasites of humans and animals and serve as vectors of many disease-causing agents. Despite past and current research efforts on fleas due to their medical and veterinary importance, correct identification and robust phylogenetic analysis of these ectoparasites have often proved challenging. Methods: We decoded the complete mitochondrial (mt) genome of the human flea Pulex irritans and nearly complete mt genome of the dog flea Ctenocephalides canis, and subsequently used this information to reconstruct the phylogeny of fleas among Endopterygota insects. Results: The complete mt genome of P. irritans was 20,337 bp, whereas the clearly sequenced coding region of the C. canis mt genome was 15,609 bp. Both mt genomes were found to contain 37 genes, including 13 protein-coding genes, 22 transfer RNA genes and two ribosomal RNA genes. The coding region of the C. canis mt genome was only 93.5% identical to that of the cat flea C. felis, unequivocally confirming that they are distinct species. Our phylogenomic analyses of the mt genomes showed a sister relationship between the order Siphonaptera and orders Diptera + Mecoptera + Megaloptera + Neuroptera and positively support the hypothesis that the fleas in the order Siphonaptera are monophyletic. Conclusions: Our results demonstrate that the mt genomes of P. irritans and C. canis are different. The phylogenetic tree shows that fleas are monophyletic and strongly support an order-level objective. These mt genomes provide novel molecular markers for studying the taxonomy and phylogeny of fleas in the future. [ABSTRACT FROM AUTHOR]

• The hydrodynamics, mixing and mass transfer of two-phase processes are reviewed. • Bubble/droplet formation mechanism and scaling models are summarized. • The dynamic behavior during formation stage is highlighted. • The circulation topology and mixing inside both droplets and slugs are discussed. • The interfacial mass transfer regimes and simulative models are presented. Microreaction technology is preferential in process intensification and chemical synthesis, especially in multiphase applications. A thorough understanding of the hydrodynamics and mass transfer is the pre-requisite for implementing such applications. This review discusses the recent progress on the flow and mass transfer of two-phase systems in microchannels, in a multi-scale view from local mechanism to global behavior. The flow patterns, the formation of bubbles/droplets, and the manipulation of bubbles/droplets are presented and discussed in detail. The mass transfer aspects include the velocity profile and mixing inside droplets/slugs, as well as the interfacial mass transfer mechanism and simulative models. The aim of the review is to show directly the physical ingredients which determine the transport phenomena, help explain the observed behavior, and guide reactor design. To simplify the physical ingredients, the attention is focused on straight channels while phenomena in other channels (e.g. , meandering channel) are neglected. [ABSTRACT FROM AUTHOR]

• The effect of fluid viscosity on liquid-liquid mass transfer was studied. • Several local transfer patterns were observed at both straight channels and bends. • Ka and K can increase with the increase in μ C at large flow rates. • Three mass transfer regimes were identified and correlated to local transfer patterns. Mass transfer characteristics of liquid-liquid Taylor flow with various fluid pairs are investigated, in order to reveal the viscous effects of the fluids. The concentration pattern in continuous slugs, mass transfer time and mass transfer coefficient are discussed and analyzed. Several different concentration patterns originated from recirculation are observed at both straight channels and curved bends, respectively. It is shown that the mass transfer coefficient (Ka and K) can increase with the increase in the viscosity of the continuous phase at large flow rates, which is explained by the increased contribution of the film at the lateral droplet side and its exchange with the bulk slug. Based on the dominance of different parts (i.e. , film, cap), three mass transfer regimes are distinguished. Correlations for each regime, which covers a wide range of fluid viscosity of 0.89–45.6 mPa·s, are developed to predict the mass transfer coefficient. [ABSTRACT FROM AUTHOR]

• Danckwerts mass transfer model is applied for absorption prediction. • Significant end effect is found in lab-scale experiments. • The effects of various parameters on the reactor volume are investigated. • Increasing the system pressure is very efficient to reduce the microreactor volume. Parametric analysis is presented for CO 2 absorption process using the Danckwerts mass transfer model, which enables an efficient target-oriented design of microreactors. Instead of trial-error evaluation over given reactors, this work provides a quantitative study on the effects of various parameters (i.e., flow rate, reaction rate, system pressure) on the reactor volume. It is found that increasing system pressure can significantly reduce the reactor volume, offsetting the disadvantage of microreactors with limited volume. This work also evaluates the end effect of lab-scale tests that results from the absorption in the connecting tube and the gas-liquid separator. With the theoretical approach, the end effect is shown to increase with the increase of the throughput, which is in accordance with experimental results. The amount of CO 2 absorbed in the end volume can be as large as 23 %∼47 % of the total CO 2 absorbed, indicating a rather serious end effect. [ABSTRACT FROM AUTHOR]

Background: Several Tritrichomonas species have been found in mammalian hosts. Among these trichomonads T. foetus is often found in the urogenital tract of cattle and the gastrointestinal tract of the domestic cat, resulting in sexually transmitted bovine trichomonosis and fecal-orally transmitted feline trichomonosis, respectively. The aims of the current study were to molecularly characterize clinical isolates of T. foetus in cattle populations in Wyoming, South Dakota, and Montana of the United States of America and to phylogenetically analyze Tritrichomonas species of mammalian hosts. Results: DNA sequencing of rRNA genes showed over 99% identity of the newly described isolates to other bovine isolates. Further, T. foetus isolates of various mammalian hosts originated in different geographic regions worldwide were clustered into two well-defined clades by phylogenetic analysis of rRNA and cysteine protease 2 genes. Clade I consisted of isolates originated from cattle, pig, and human whereas clade II contained isolates of cat and dog. Conclusion: It is concluded that all mammalian Tritrichomonas spp. apparently belong to T. foetus. Analysis of more sequences is warranted to support this conclusion. [ABSTRACT FROM AUTHOR]

Parasitic roundworms (nematodes) have lost genes involved in the de novo biosynthesis of haem, but have evolved the capacity to acquire and utilise exogenous haem from host animals. However, very little is known about the processes or mechanisms underlying haem acquisition and utilisation in parasites. Here, we reveal that HRG-1 is a conserved and unique haem transporter in a broad range of parasitic nematodes of socioeconomic importance, which enables haem uptake via intestinal cells, facilitates cellular haem utilisation through the endo-lysosomal system, and exhibits a conspicuous distribution at the basal laminae covering the alimentary tract, muscles and gonads. The broader tissue expression pattern of HRG-1 in Haemonchus contortus (barber's pole worm) compared with its orthologues in the free-living nematode Caenorhabditis elegans indicates critical involvement of this unique haem transporter in haem homeostasis in tissues and organs of the parasitic nematode. RNAi-mediated gene knockdown of hrg-1 resulted in sick and lethal phenotypes of infective larvae of H. contortus, which could only be rescued by supplementation of exogenous haem in the early developmental stage. Notably, the RNAi-treated infective larvae could not establish infection or survive in the mammalian host, suggesting an indispensable role of this haem transporter in the survival of this parasite. This study provides new insights into the haem biology of a parasitic nematode, demonstrates that haem acquisition by HRG-1 is essential for H. contortus survival and infection, and suggests that HRG-1 could be an intervention target candidate in a range of parasitic nematodes. Author summary: Parasitic nematodes cannot synthesise haem de novo and must exploit haem from the environment or host animals. Mechanisms securing haem acquisition and its systemic distribution in these pathogens remain to be elucidated. In the present study, we identify a unique haem transporter HRG-1 in a range of nematodes commonly found in animals, which shows haem binding activity in vitro, haem transporting activity in yeast, and an important role in haem homeostasis in the free-living model organism Caenorhabditis elegans. This transporter distributes in the basal laminae and interacts with a vacuolar ATPase in Haemonchus contortus (a paradigm and model to screen anthelmintic targets), enabling haem transport among tissues in this parasitic nematode. RNAi-mediated gene knockdown of hrg-1 results in decreased viability of the infective larvae of barber's pole worm, which cannot establish infection or survive in the host animal. The uniqueness and essentiality of HRG-1 in this parasitic nematode provide novel insights into the haem uptake and distribution in helminths and a target candidate for the control of nematode infection. [ABSTRACT FROM AUTHOR]

Background: The family Capillariidae is a group of thread-like nematodes of 27 genera and over 300 species that infect a great variety of hosts including humans. Among these, some taxa such as the genus Aonchotheca have remained controversial regarding their systematic status for decades. The aim of the current study was to verify Aonchotheca's systemic status and to further determine whether it is a distinct genus from Capillaria using molecular and phylogenetic analyses. Results: We sequenced the mitochondrial (mt) genome and nuclear small subunit (18S) rRNA gene of Aonchotheca putorii, a representative species of the genus, and investigated its systematic status in Trichinellida using maximum likelihood and Bayesian inference. The differences in amino acid sequences of 13 protein-coding genes were 12.69–67.35% among Aonchotheca, Capillaria, Eucoleus, and Pseudocapillaria with cox1 (12.69%) and atp8 (67.35%) as the most and the least conserved gene, respectively, and the difference of two mt rRNAs was 18.61–34.15%. Phylogenetic analyses of the complete mt genome and 18S rRNAs unequivocally showed that Aonchotheca was a distinct genus from Capillaria. Conclusions: Large difference exists among Aonchotheca, Capillaria, Eucoleus, and Pseudocapillarias. Aonchotheca putorii is the first species in the genus Aonchotheca for which a complete mitogenome has been sequenced. These data are useful for phylogenetics, systematics and the evolution of Capillariidae. [ABSTRACT FROM AUTHOR]

The vapor-liquid equilibrium (VLE) of CO2 in a reactive solvent is essential for the proper simulation and design of CO2 absorption processes. This work presents a systematic investigation on CO2 absorption in various aqueous monoethanolamine (MEA) solutions. CO2 solubility in MEA was measured at 298, 313, 333, and 353 K with CO2 partial pressure ranging from 34.5 to 78.0 kPa. A modified Kent-Eisenberg model was developed based on the measured solubility data, showing good predictions over the liquid phase speciation for the CO2-H2O-MEA system. We presented a new analysis based on the first-order difference curve of distribution profiles of the species. Based on the main reactions that occurred, the CO2 absorption process was demonstrated to be divided into four regions with increasing CO2 loading from 0 to 1. Accordingly, kinetic study was proposed to be conducted in the first region, whereas measuring of mass transfer in the first three regions. The findings in this work extend the existing knowledge of CO2 absorption process in terms of speciation and can provide important guidance for further study of the process characteristics using aqueous amine absorbents. [ABSTRACT FROM AUTHOR]

Simple Summary: Toxoplasmosis is one of the most common parasitic zoonoses in the world. It not only threatens human health and safety but also causes considerable losses to the global animal husbandry industry. Swine, as an intermediate host of Toxoplasma gondii, has important economic and public health significance, and the global prevalence of T. gondii in swine varies between 10% and 60%. Therefore, it is important to establish simple, effective, sensitive and specific diagnostic methods for the detection and prevention of T. gondii infection in swine. In the present study, we developed a colloidal gold immunochromatographic strip based on rTgROP14, recombinant protein A and monoclonal antibody TgROP14-5D5 for serological detection of T. gondii in swine populations. This new ICT achieved good specificity and sensitivity and has potential for routine serological detection of T. gondii in swine. Toxoplasma gondii, a worldwide distributed apicomplexan protozoan, can infect almost all warm-blooded animals and may cause toxoplasmosis. In order to provide a point-of-care detection method for T. gondii infection, an immunochromatographic test (ICT) was established. The proposed test uses recombinant T. gondii rhoptry protein 14 (ROP14) conjugated with 20 nm gold particles, recombinant protein A as the detection line and monoclonal antibody TgROP14-5D5 as the control line. The specificity, sensitivity, positive predictive value, negative predictive value and stability of this new ICT were evaluated. rTgROP14 was specifically recognized by positive serum of T. gondii but not negative serum. mAb TgROP14-5D5 showed higher specific recognition of T. gondii antigens and was therefore selected for subsequent colloidal gold strip construction. The new ICT based on TgROP14 exhibited good diagnostic performance with high specificity (86.9%) and sensitivity (90.9%) using IHA as a "reference standard". Among 436 field porcine sera, ICT and IHA detected 134 (30.7%) and 99 (22.7%) positive samples, respectively. The relative agreement was 87.8%. These data indicate that this new ICT based on TgROP14 is a suitable candidate for routine testing of T. gondii in the field. [ABSTRACT FROM AUTHOR]

A microreactor system was developed to investigate the cyclization of pseudoionone (PI) catalyzed by sulfuric acid. The conversion of PI and selectivities of α-ionone and β-ionone were explored under various conditions. The effects of residence time, molar ratio of acid/PI (M-ratio), reaction temperature, and sulfuric acid concentration on the reaction were evaluated. Sulfuric acid concentration was found to play a vital role in the reaction system, which could greatly influence the conversion and selectivities. A high yield of β-ionone and total yield of α-ionone and β-ionone were achieved under optimized conditions. The formation of by-products was determined in detail and the side reactions could be restrained by optimizing the reaction parameters. [ABSTRACT FROM AUTHOR]

[Display omitted] • Multiphase processes containing solid in microchannels stably manipulated. • Hydrodynamics of Pickering emulsion systems in microchannels characterised. • A scaling law of droplets size as a function of Q d / Q c , μ d / μ c and Ca established. In this work, a method based on Pickering emulsion systems (PES) was proposed to manipulate multiphase processes containing solid particles in microchannels without adhesion and/or accumulation. The flow hydrodynamics of PES in a microchannel were systematically characterized. For comparison, a suspension system (SS, ethyl acetate with suspended SiO 2 nanoparticles-water) and a viscous fluid system (VFS, ethyl acetate with methyl-silicone oil–water) were examined. It was found liquid–liquid two-phase characteristics of PES, SS and VFS around T-junction within the main microchannel depended on surface hydrophobicity of stabilizing SiO 2 nanoparticles, amount of SiO 2 particles added, viscosity and flow rate. Four flow patterns were observed under these operating conditions for PES and VFS, where superficial velocity was the key factor affecting the flow patterns transition. Finally, a scaling law of the droplet size was established as a function of Q d / Q c , μ d / μ c and Ca. [ABSTRACT FROM AUTHOR]

• An efficient ultrasonic assisted microreactor for emulsification was developed. • A distinct cavitation pattern with an array of bubble clusters was observed. • The bubble cluster was composed of many fine bubbles in emulsion systems. • A semi-empirical correlation was proposed to predict the emulsion size. • A high energy efficiency of 0.03–2.77% was achieved in the novel device. An ultrasonic assisted microreactor (USMR) for emulsification was designed. Uniform sound distribution in the microchannel and effective temperature control were realized. The oscillation behavior of cavitation bubbles in coarse oil-in-water emulsion was investigated in two other ultrasonic microreactors with similar structure. It was found that bubble clusters composed of many fine bubbles vibrated as a whole, similar to the vibration of single bubbles. It was easier for the bubble clusters to oscillate under the transient oscillation mode, compared to a cavitation bubble. Due to the secondary sound field, it formed a uniform array of bubble clusters in straight channel and stagnant bursting cavitation zones with strong shocking wave in meandering channel. Parametric study on the emulsification performance was also conducted. A semi-empirical correlation was proposed and showed excellent predicting performance over the emulsion size. Due to the controlled sound field and cavitation bubbles of the USMR, the energy efficiency ranged from 0.03 to 2.77%, which was at least one order of magnitude higher than conventional ultrasonic devices that do not directly couple the microchannel and vibrator. [ABSTRACT FROM AUTHOR]

[Display omitted] • Haemonchus contortus protein Hc -SPI-I8A functions as an inhibitor of blood clotting contributed by the TIL domain. • Hc -SPI-I8 is highly expressed in the parasitic stages and at the hypodermis, intestine and gonads of H. contortus. • Hc -SPI-I8 was in the same clade as the homologues, which could inhibit coagulation by interacting with clotting factors. • Hc -SPI-I8A is most likely disturbing the extrinsic coagulation cascade by interacting with Oa TSP1CP through its TIL domain. • Hc -SPI-I8A might also interfering in the intrinsic coagulation cascade by an unknown mechanism. Haemonchus contortus , a blood-feeding nematode, inhibits blood coagulation at the site of infection to facilitate blood-sucking and digesting for successful parasitism. However, the mechanism underlying anti-coagulation at the host-parasite interface is largely unknown. In the current study, Hc-spi-i8 , which has two greatly different transcripts named Hc-spi-i8a and Hc-spi-i8b , respectively, was described. Hc -SPI-I8A was a serine protease inhibitor containing a trypsin inhibitor-like cysteine rich (TIL) domain, while Hc -SPI-I8B was not. Hc -SPI-I8A/B were primarily expressed in the hypodermis, intestines and gonads in the parasitic stages of H. contortus. Hc -SPI-I8A interacted with Ovis aries TSP1-containing protein (Oa TSP1CP), which was determined by yeast two-hybrid, co-immunoprecipitation (Co-IP), pull down and co-localization experiments. The blood clotting time contributed by the TIL domain was prolonged by Hc -SPI-I8A. Hc -SPI-I8A is most likely interfering in the extrinsic coagulation cascade by interacting with Oa TSP1CP through its TIL domain and intrinsic coagulation cascade by an unknown mechanism. These findings depict a crucial point in the host-parasite interaction during H. contortus colonization, which should contribute to drug discovery and vaccine development in fighting against this important parasite worldwide. [ABSTRACT FROM AUTHOR]

Highlights: [•] Process of CO2 absorption by MEA solutions was analyzed in microchannel reactors. [•] Effects of relevant parameters on the process were evaluated. [•] k 1 for CO2 reaction with MEA was successfully determined under ambient pressure. [•] An Arrhenius-type equation was obtained for k 1 for CO2 absorption in microchannel. [Copyright &y& Elsevier]

• The effects of both μ c and μ d on slug flow are investigated. • The slug flow occurrence is predicted based on composite dimensionless numbers. • For squeezing regime, the droplet scaling law is different from the classical theory. • The film thickness increased more rapidly with Ca D than in gas–liquid slug flow. • Correlations were proposed to reflect the effect of recirculations in both phases on the pressure drop. The hydrodynamics of liquid–liquid slug flow with various fluid systems were investigated, aiming at revealing the viscous effects of both phases. The operation range, droplet formation, film thickness and pressure drop of slug flow were studied and discussed. The results reveal the importance of inertia and viscous forces of both phases in the transition of flow patterns. Accordingly, a universal flow map based on composite terms of Ca c Re c 0.5 and Ca d Re d 0.5 was adopted, which worked well for a wide viscosity range. For droplet formation in the present system, both the squeezing and shearing regimes deviated from the classical ideal models. Under higher capillary number, the film was accumulated at the corners and lateral planes, leading to distinct droplet shapes from literature. For the two-phase pressure drop, new empirical correlations were proposed to describe the recirculation inside both the droplets and slugs. The findings can provide better guidance for optimized reactor design. [ABSTRACT FROM AUTHOR]

Hypobiosis (facultative developmental arrest) is the most important life-cycle adaptation ensuring survival of parasitic nematodes under adverse conditions. Little is known about such survival mechanisms, although ascarosides (ascarylose with fatty acid-derived side chains) have been reported to mediate the formation of dauer larvae in the free-living nematode Caenorhabditis elegans. Here, we investigated the role of a key gene acox-1, in the larval development of Haemonchus contortus, one of the most important parasitic nematodes that employ hypobiosis as a routine survival mechanism. In this parasite, acox-1 encodes three proteins (ACOXs) that all show a fatty acid oxidation activity in vitro and in vivo, and interact with a peroxin PEX-5 in peroxisomes. In particular, a peroxisomal targeting signal type1 (PTS1) sequence is required for ACOX-1 to be recognised by PEX-5. Analyses on developmental transcription and tissue expression show that acox-1 is predominantly expressed in the intestine and hypodermis of H. contortus, particularly in the early larval stages in the environment and the arrested fourth larval stage within host animals. Knockdown of acox-1 and pex-5 in parasitic H. contortus shows that these genes play essential roles in the post-embryonic larval development and likely in the facultative arrest of this species. A comprehensive understanding of these genes and the associated β-oxidation cycle of fatty acids should provide novel insights into the developmental regulation of parasitic nematodes, and into the discovery of novel interventions for species of socioeconomic importance. Author summary: Haemonchus contortus is one of the most pathogenic nematodes causing substantial economic losses worldwide that undergo facultative arrest (diapause) to survive harsh environmental and host conditions. However, the molecular basis (e.g., fatty acid oxidation and dauer pheromone synthesis) underlying such survival mechanisms has not yet been elucidated in parasitic nematodes. Here, we show that an acyl-CoA oxidase ACOX-1 interacts with a peroxin PEX-5 and functions in fatty acid oxidation in peroxisomes. Further, knockdown of ACOX-1 and PEX-5 results in a lethal phenotype of the infective stage and likely developmental parasitic larval stage within host animals. This data demonstrates an essential role of ACOX-1-PEX-5 and potentially ascarosides signalling in the facultative arrested larval development of parasitic nematodes, and suggests possible intervention targets. [ABSTRACT FROM AUTHOR]

[Display omitted] • USMRs with tailored frequencies, sizes, and power outputs were developed. • A comprehensive map of cavitation patterns in USMRs was proposed. • The slug cluster pattern was identified for superior mixing performance. • A mixing model for USMRs operating under slug cluster patterns was developed. • A seamless scale-up strategy for antisolvent precipitation via USMRs was presented. In this study, a seamless scale-up strategy for the antisolvent precipitation process was developed using a series of ultrasonic microreactors (USMRs). The key principle of this scale-up strategy was to maintain a constant mixing time, ensuring consistent nanoparticle (NP) production across different scales. First, lab- and production-scale USMRs were developed, enabling the customization of reactors to varying ultrasound frequencies, channel diameters, and power outputs. Then, the distinct cavitation patterns, including array, slug cluster and cluster, along with their corresponding mixing performances were studied in nine USMRs. By establishing a comprehensive map of cavitation patterns, primary factors affecting the formation of cavitation patterns were identified. Among the three cavitation patterns, the slug cluster pattern demonstrated the best mixing performance, wherein cavitation bubbles effectively occupied the channel and traversed rapidly across the cross-section. To guide the operation of USMRs under the slug cluster pattern, a tailored mixing model was developed. This model, in combination with the relationship between NP size and mixing time, enabled the successful seamless scale-up production of 55 nm PLGA-PEG NPs, with a required mixing time of 27 ms. This USMR-based scale-up strategy facilitated efficient process screening with low sample consumption (2 mL/min, 200 μL/sample) as well as high-throughput production (100 mL/min, 30 g/h). [ABSTRACT FROM AUTHOR]