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Individual hosts are often co-infected with multiple parasite species. Evidence from theoretical and empirical studies supports the idea that co-occurring parasites can impact each other and their hosts via synergistic or antagonistic interactions. The fundamental aim of understanding the consequences of co-infection to hosts and parasites requires an understanding of patterns of species co-occurrence within samples of hosts. We censused parasite assemblages in 755 adult, male fathead minnows collected from 7 lakes/ponds in southern Alberta, Canada between 2018 and 2020. Fifteen species of endoparasites infected fathead minnows, 98% of which were co-infected with between 2 and 9 parasite species (mean species richness: 4.4 ± 1.4). Non-random pairwise associations were detected within the overall parasite community. There were particularly strong, positive associations in the occurrences and intensities of the 2 congeneric larval trematodes Ornithodiplostomum sp. and Ornithodiplostomum ptychocheilus that comprised >96% of the 100 000+ parasites counted in the total sample of minnows. Furthermore, the occurrence of Ornithodiplostomum sp. was a strong predictor of the occurrence of O. ptychocheilus, and vice versa. Positive covariation in the intensities of these 2 dominants likely arises from their shared use of physid snails as first intermediate hosts in these waterbodies. These 2 species represent a predictable and non-random component within the complex assemblage of parasites of fathead minnows in this region.

Identifying factors that drive among-individual variation in mixed parasitic infections is fundamental to understanding the ecology and evolution of host–parasite interactions. However, a lack of non-invasive diagnostic tools to quantify mixed infections has restricted their investigation for host populations in the wild. This study applied DNA metabarcoding on parasite larvae cultured from faecal samples to characterize mixed strongyle infections of 320 feral horses on Sable Island, Nova Scotia, Canada, in 2014 to test for the influence of host (age, sex and reproductive/social status) and environmental (location, local density and social group membership) factors on variation. Twenty-five strongyle species were identified, with individual infections ranging from 3 to 18 species with a mean richness (±1 s.d. ) of 10.8 ± 3.1. Strongyle eggs shed in faeces were dominated by small strongyle (cyathostomins) species in young individuals, transitioning to large strongyles ( Strongylus spp.) in adults. Egg counts were highest in young individuals and in the west or centre of the island for most species. Individuals in the same social group had similar parasite communities, supporting the hypothesis that shared environment may drive parasite assemblages. Other factors such as local horse density, sex, date and reproductive/social status had minimal impacts on infection patterns. This study demonstrates that mixed infections can be dynamic across host ontogeny and space and emphasizes the need to consider species-specific infection patterns when investigating mixed infections.

The dilution effect describes the negative association between host biodiversity and the risk of infectious disease. Tests designed to understand the relative roles of host species richness, host species identity, and rates of exposure within experimental host communities would help resolve ongoing contention regarding the importance and generality of dilution effects. We exposed fathead minnows to infective larvae of the trematode, Ornithodiplostomum ptychocheilus in minnow‐only containers and in mixed containers that held 1–3 other species of fish. Parasite infection was estimated as the number of encysted worms (i.e., brainworms) present in minnows following exposure. The results of exposure trials showed that nonminnow fish species were incompatible with O. ptychocheilus larvae. There was no reduction in mean brainworm counts in minnows in mixed containers with brook sticklebacks or longnose dace. In contrast, brainworm counts in minnows declined by 51% and 27% in mesocosms and aquaria, respectively, when they co‐occurred with emerald shiners. Dilution within minnow + shiner containers may arise from shiner‐induced alterations in minnow or parasite behaviors that reduced encounter rates between minnows and parasite larvae. Alternatively, shiners may act as parasite sinks for parasite larvae. These results highlight the role of host species identity in the dilution effect. Our results also emphasize the complex and idiosyncratic effects of host community composition on rates of parasite infection within contemporary host communities that contain combinations of introduced and native species. The effects of host diversity on rates of parasite infection are context‐dependent. When fathead minnows swim in containers with one non‐host competitor (longnose dace), rates of infection into minnows are the same as when minnows swim in containers by themselves. In contrast, when minnows swim in containers with another species of non‐host competitor (emerald shiners), infection rates decrease by more than 50%.

This thesis aims to determine how parasite transmission responds to temporal, spatial, or ecological factors such as host biodiversity. For this study, I used a fathead minnow/trematode parasite study system and incorporated both field and experimental components. Long-term data on the parasite population sizes in fathead minnows from two lakes in Alberta indicate that parasite population sizes are highly variable. Simultaneous infections by multiple parasite species in fathead minnows is the norm, with closely related parasite species exhibiting similar long-term trends in population dynamics. Increases in host biodiversity is thought to decrease parasite transmission, however, my experiments indicate that biodiversity is not directly causing a decrease in transmission of the trematode Ornithodiplostomum ptychocheilus into fathead minnows. Instead, I suggest that the mechanism behind the decline in transmission is the species-specific modulation of transmission pathways as host biodiversity increases.

In this paper, we proposed an integrated microfluidic device that could demonstrate the non-contact, label-free separation of particles and cells through the combination of inertial microfluidics and acoustophoresis. The proposed device integrated two microfluidic chips which were a PDMS channel chip on top of the silicon-based acoustofluidic chip. The PDMS chip worked by prefocusing the particles/cells through inducing the inertial force of the channel structure. The connected acoustofluidic chips separated particles based on their size through an acoustic radiation force. In the serpentine-shaped PDMS chip, particles formed two lines focusing in the channel, and a trifugal-shaped acoustofluidic chip displaced and separated particles, in which larger particles focused on the central channel and smaller ones moved to the side channels. The simultaneous fluidic works allowed high-efficiency particle separation. Using this novel acoustofluidic device with an inertial microchannel, the separation of particles and cells based on their size was presented and analyzed, and the efficiency of the device was shown. The device demonstrated excellent separation performance with a high recovery ratio (up to 96.3%), separation efficiency (up to 99%), and high volume rate (>100 µL/min). Our results showed that integrated devices could be a viable alternative to current cell separation based on their low cost, reduced sample consumption and high throughput capability.

Emotions in speech are expressed in various ways, and the speech emotion recognition (SER) model may perform poorly on unseen corpora that contain different emotional factors from those expressed in training databases. To construct an SER model robust to unseen corpora, regularization approaches or metric losses have been studied. In this paper, we propose an SER method that incorporates relative difficulty and labeling reliability of each training sample. Inspired by the Proxy-Anchor loss, we propose a novel loss function which gives higher gradients to the samples for which the emotion labels are more difficult to estimate among those in the given minibatch. Since the annotators may label the emotion based on the emotional expression which resides in the conversational context or other modality but is not apparent in the given speech utterance, some of the emotional labels may not be reliable and these unreliable labels may affect the proposed loss function more severely. In this regard, we propose to apply label smoothing for the samples misclassified by a pre-trained SER model. Experimental results showed that the performance of the SER on unseen corpora was improved by adopting the proposed loss function with label smoothing on the misclassified data.

This study presents an equivalent circuit model for the analysis of wireless power transfer (WPT) through both electric and magnetic couplings using merely a resonant coupler. Moreover, the frequency split phenomenon, which occurs when transmitting couplers are near receiving couplers, is explained. This phenomenon was analyzed using simple circuit models derived via a mode decomposition technique. To verify the proposed method, a resonant coupler using mixed coupling was designed and its efficiency was compared with the result obtained using a commercial electromagnetic solver. The results of this study are expected to aid in designing various WPT couplers or sensor antennas by selecting electric, magnetic, or mixed couplings. Furthermore, the results of this study are expected to be applied to technologies that sense objects, or simultaneously transmit and receive information and power wirelessly.

We used 3D printed-breast surgical guides (3DP-BSG) to designate the original tumor area from the pre-treatment magnetic resonance imaging (MRI) during breast-conserving surgery (BCS) in breast cancer patients who received neoadjuvant systemic therapy (NST). Targeting the original tumor area in such patients using conventional localization techniques is difficult. For precise BCS, a method that marks the tumor area found on MRI directly to the breast is needed. In this prospective study, patients were enrolled for BCS after receiving NST. Partial resection was performed using a prone/supine MRI-based 3DP-BSG. Frozen biopsies were analyzed to confirm clear tumor margins. The tumor characteristics, pathologic results, resection margins, and the distance between the tumor and margin were analyzed. Thirty-nine patients were enrolled with 3DP-BSG for BCS. The median nearest distance between the tumor and the resection margin was 3.9 cm (range 1.2–7.8 cm). Frozen sections showed positive margins in 4/39 (10.3%) patients. Three had invasive cancers, and one had carcinoma in situ; all underwent additional resection. Final pathology revealed clear margins. After 3-year surveillance, 3/39 patients had recurrent breast cancer. With 3DP-BSG for BCS in breast cancer patients receiving NST, the original tumor area can be identified and marked directly on the breast, which is useful for surgery. Trial Registration : Clinical Research Information Service (CRIS) Identifier Number: KCT0002272. First registration number and date: No. 1 (27/04/2016).

Purpose Local anesthetic adjuvants have been studied previously in an attempt to prolong the duration of analgesia after peripheral nerve blockade. Magnesium has been shown to have an antinociceptive effect in animal and human pain models. We evaluated the effects of adding magnesium sulphate to long-acting local anesthetics for interscalene nerve block to prolong the duration of analgesia and improve the analgesic quality. Methods We enrolled 66 patients undergoing arthroscopic rotator cuff repair. The interscalene nerve block was performed with 0.5% bupivacaine 20 mL with epinephrine (1:200,000) plus either 10% magnesium sulphate 2 mL (Magnesium Group) or normal saline 2 mL (Saline Group). The following data were recorded for 24 hr after surgery: onset times and durations of sensory and motor blocks, analgesic duration, the pain numeric rating scale (NRS), postoperative fentanyl consumption, and complications. Results The duration of analgesia was longer in the Magnesium Group than in the Saline Group [mean and (standard deviation) 664 (188) min vs 553 (155) min, respectively; P  = 0.017]. Patients in the Magnesium Group had significantly reduced pain NRS scores at 12 hr ( P  = 0.012), but the cumulative fentanyl consumption was similar in both groups. The onset times and durations of sensory and motor blocks were not significantly different between the two groups. Conclusion The addition of magnesium sulphate to a bupivacaine-epinephrine mixture for interscalene nerve block prolongs the duration of analgesia and reduces postoperative pain.

Spiegelmers are enantiomers of natural D-oligonucleotides that bind to targets with distinct structures such as aptamers. The high susceptibility of natural D-form aptamers to nucleases greatly hinders their application in biological environments. Here, a nonbiodegradable spiegelmer-based platform for the sensitive detection of bisphenol A (BPA) was developed. Due to the symmetric molecule of BPA, the D-form aptamer can be directly converted into mirror forms via chemical synthesis. Aptamer–target interactions that involve chemically synthesized spiegelmers were characterized by biolayer interferometry, and their stabilities were tested in various biological fluids by exposure to nucleases. We demonstrate for the first time the use of a nuclease-resistant spiegelmer in a simple, label-free gold nanoparticle-based colorimetric assay to detect BPA in a highly sensitive and selective manner. The aptasensor exhibits an LOD of 0.057 ng/mL and dynamic range of 105 (100 pg/mL to 10 mg/mL). With sensing capacity and biological stability, the developed aptasensor shows great potential to utilize in in-field applications such as water quality monitoring.