A CNN-LSTM model using elliptical constraints for temporally consistent sun position estimation.

More accurate sun position estimation could transform the design and operation of solar power systems, weather forecasting services, and outdoor augmented reality systems. Although several image-based approaches to sun position estimation have been proposed, their performance is significantly affected by momentary disruptions in cloud cover because they use only a single image as input. This study proposes a deep learning-based sun position estimation system that leverages spatial, temporal, and geometric features to accurately regress sun positions even when the sun is partially or entirely occluded. In the proposed approach, spatial features are extracted from an input image sequence by applying a separate Resnet-based convolution network to each frame. To ensure that the temporal changes in the brightness distribution across frames are considered, the spatial features are concatenated and passed on to a stack of LSTM layers prior to regressing the final sun position. The proposed network is also trained with elliptical (geometric) constraints to ensure that predicted sun positions are consistent with the natural elliptical path of the sun in the sky. The proposed approach's performance was evaluated on the Sirta and Laval datasets along with a custom dataset, and an R2 Score of 0.98 was achieved, which is at least 0.1 higher than that of previous approaches. The proposed approach is capable of identifying the position of the sun even when occluded and was employed in a novel sky imaging system consisting of only a camera and fisheye lens in place of a complex array of sensors.

Metastatic intestinal adenocarcinoma with osseous metaplasia in two Domestic Korean Shorthair cats.

Two Domestic Korean Shorthair cats presented with dyschezia and vomiting. Computed tomography revealed a colonic mass with calcification and lymph node metastasis in case 1, and a small intestinal mass with disseminated mesenteric metastasis and calcification in case 2. Histopathology revealed intestinal adenocarcinoma with osseous metaplasia. Case 1 died two months after surgery from distant metastasis; and case 2 showed no metastasis for five months but presented with anorexia, euthanized seven months after diagnosis. Metastatic intestinal adenocarcinoma with bone formation should be considered as differential diagnosis for calcification on imaging, and lymph node metastasis at diagnosis may indicate poor prognosis.

Flow cytometric characterization of the hemocytes of sea hares from tidal pools in Jeju Island off the south coast of Korea.

The members in the family Aplysidae known as sea hares play a crucial role as a grazer in small tidal pools or shallow subtidal hard bottoms. Like other marine gastropods, hemocyte types and functions of sea hares are limitedly known. This study identified and characterized the hemocytes of common Aplysia species Aplysia kurodai, A. juliana, and A. oculifera in rocky tidal pools in Jeju Island off the south coast of Korea using flow cytometry and light microscopy. The flow cytometry identified three different hemocytes in the hemolymph of the three sea hare species: granulocytes, hyalinocytes, and blast-like cells. The granulocytes exhibited pseudopodia on the cell surface and granules in the cytoplasm. Morphology of the hyalinocyte was similar to that of the granulocytes, while they lack cytoplasmic granules. The blast-like cells were small and round, with very thin cytoplasm. The hyalinocytes were the most abundant in the hemolymph, accounting for 89.8-92.6% of the total hemocytes. Flow cytometry indicated that the granulocytes and blast-like cells were less than 5.6% and 5.4% of the total hemocyte populations. Flow cytometry also revealed that the granulocytes and hyalinocytes are engaged in cellular defensive activities such as intra-cellular lysosomal content, phagocytosis, and ROS production. The mean lysosomal contents of the granulocytes (0.4 × 105-0.2 × 105 A U.) were 2-3 times higher than that of hyalinocytes (0.2 × 105-0.6 × 105 A U.). In addition, the ROS production of the granulocytes (0.98 × 106-1.95 × 106 A U.) was about twice higher than that of the hyalinocytes (0.62 × 106-1.14 × 106 A U.). Of the three species of sea hares, the granulocytes showed comparatively higher phagocytosis capacity (70.4-92.3%) than that of the hyalinocytes (34.8-46.0%). Flow cytometry and microscopy indicated that the hemocyte types and their functions were identical, regardless of the species.

Effects of spawning stress on the immune capacity of blood cockle Tegillarca granosa occurring on the south coast of Korea.

Spawning in marine bivalves is a great energy-demanding process, and it often results in lethal and sublethal stresses during the post-spawning period, including depressed immune capacity. The blood cockle Tegillarca granosa (Linnaeus, 1758) distributes widely in silty-mud tidal flats on the south coast of Korea, and they spawn in late summer. To understand the impacts of spawning on immune parameters, we analyzed the total hemocyte count (THC), hemocyte mortality, phagocytosis capacity, and reactive oxygen species (ROS) production of T. granosa in pre-, and post-spawning condition using a flow cytometer. Histology indicated that the blood cockles occurring on the south coast of Korea ripe and ready to spawn in July, and they spawned in August and September. The THC in the blood cockle hemolymph declined from pre-spawning (1.2 × 108 cell mL-1) to post-spawning (0.9 × 108 cell mL-1), possibly due to the spawning stress and the massive infiltration of hemocytes in the gonad to phagocytose and resorb the residual gametes during the post-spawning period. The hemocyte mortality increased linearly from August (4.1%) to November (9.1%), as the histology revealed that the blood cockle completed spawning, and they resorbed the relict gametes. The granulocyte phagocytosis capacity declined dramatically from July (12.7%) to September (6.0%), when the cockles were engaged in active spawning. The flow cytometry revealed that the production of reactive oxygen species (ROS) from the granulocytes and the erythrocytes type II increased linearly from August (0.8-0.9 × 105 A U.) to December (2.1-2.8 × 105 A U.), which may cause stresses at a cellular level during this period. As the data indicated, spawning is a stressful activity inducing depressed immunological capacities in the blood cockles.

Flow cytometric characterization of the hemocytes of blood cockles Anadara broughtonii (Schrenck, 1867), Anadara kagoshimensis (Lischke, 1869), and Tegillarca granosa (Linnaeus, 1758) as a biomarker for coastal environmental monitoring.

Marine bivalves are often used as a sentinel species in coastal environmental monitoring since changes in the environmental quality are often well preserved in their cells and tissues. Anadara and Tegillarca species of Arcidae, the blood cockles, are considered to be good sentinel species in monitoring coastal pollution and ecosystem health because they are distributed widely in the subsurface of intertidal mudflats. Internal cellular defense of the blood cockles to physical and biological stresses is mediated by the circulating hemocytes, while their hemocyte types and functions are poorly studied. In this study, we first characterized morphology and immune-related activities of hemocytes of three common blood cockles Anadara broughtonii, A. kagoshimensis, and Tegillarca granosa using flow cytometry. Based on cell morphology and immunological functions, we described five types of hemocytes identically in the three blood cockles: erythrocytes type-I (erythrocytes-I), erythrocytes type-II (erythrocytes-II), granulocytes, hyalinocytes, and blast-like cells. Erythrocytes were round cells containing hemoglobin with numerous granules in the cytoplasm and these cells consist of two central populations. Erythrocytes-I were the most abundant cells accounting for 80-89% of the total circulating hemocytes and exhibited a certain level of lysosome and oxidative capacity. Erythrocytes-II were the largest cells and displayed high lysosome content and the most active oxidative capacity. Both erythrocytes-I and erythrocytes-II did not show phagocytosis capacity. Granulocytes were intermediated-sized hemocytes characterized by granules in the cytoplasm and long pseudopodia on the cell surface, and these cells were mainly engaged in the cellular defense exhibiting the largest lysosome content, the most active phagocytosis, and high oxidative capacity. Contrary to granulocytes, hyalinocytes were comparatively small and round cells and exhibited no granules in the cytoplasm. Hyalinocytes displayed a certain level of lysosome and phagocytosis and oxidative capacities. Blast-like cells characterized by the smallest size and small quantity of cytoplasm and exhibited an absence of phagocytosis and extremely low oxidative capacity, suggesting that this population is not directly involved in the cell-mediated immune activities. In conclusion, flow cytometry indicated that three blood cockles had five types of hemocytes, and the erythrocytes and granulocytes were mainly involved in the immunological activities.

Temporal changes in hemocyte functions of the oyster Saccostrea kegaki (Torigoe & Inaba, 1981) on Jeju Island off the south coast of Korea are closely associated with annual gametogenesis.

Hemocyte parameters have been used as a proxy to characterize the health condition of marine bivalves, as the effects of external and internal stresses are reflected well in these parameters. Marine bivalve hemocyte functions are often depressed during the post-spawning period due to physiological stress and energy depletion. In this study, we analyzed temporal changes in hemocyte parameters of the oyster Saccostrea kegaki on Jeju Island, off the south coast of Korea, using flow cytometry. Total hemocyte count (THC), hemocyte types, hemocyte mortality, and phagocytosis capacity were analyzed. S. kegaki spawned during June and August, when the sea surface temperature increased from 18 to 23 °C. Most of the oysters were in the spent and resting phases from September to January. THC dropped dramatically from September to October, when most oysters completed spawning. Histology revealed that the residual eggs or sperm were actively resorbed through phagocytosis by hemocytes during the spent stage. Hemocyte mortality also showed its annual peak in October, possibly due to increased resorbing activities. The phagocytosis capacities of the granulocytes decreased dramatically from September to February. The level of energy reserves (glycogen) in post-spawning tissues was significantly lower than that prior to spawning. The low energy level reserve during the post-spawning period likely reduced the THC and immune capacities, as oysters may have been unable to acquire sufficient food from the ambient environment.

Neural correlates of anxiety under interrogation in guilt or innocence contexts.

Interrogation elicits anxiety in individuals under scrutiny regardless of their innocence, and thus, anxious responses to interrogation should be differentiated from deceptive behavior in practical lie detection settings. Despite its importance, not many empirical studies have yet been done to separate the effects of interrogation from the acts of lying or guilt state. The present fMRI study attempted to identify neural substrates of anxious responses under interrogation in either innocent or guilt contexts by developing a modified "Doubt" game. Participants in the guilt condition showed higher brain activations in the right central-executive network and bilateral basal ganglia. Regardless of the person's innocence, we observed higher activation of the salience, theory of mind and sensory-motor networks-areas associated with anxiety-related responses in the interrogative condition, compared to the waived conditions. We further explored two different types of anxious responses under interrogation-true detection anxiety in the guilty (true positive) and false detection anxiety in the innocent (false positive). Differential neural responses across these two conditions were captured at the caudate, thalamus, ventral anterior cingulate and ventromedial prefrontal cortex. We conclude that anxiety is a common neural response to interrogation, regardless of an individual's innocence, and that there are detectable differences in neural responses for true positive and false positive anxious responses under interrogation. The results of our study highlight a need to isolate complex cognitive processes involved in the deceptive acts from the emotional and regulatory responses to interrogation in lie detection schemes.

Combination Therapy Comprising a Static Magnetic Field with Contractility Improves Skin Wounds.

Cutaneous wounds can present significant clinical problems because of abnormal healing after deep dermal damage. Despite technical advances in wound care, there are still unmet needs that result from inefficient treatment. In this study, we aimed to improve skin wound healing using a contractibility band with static magnetic field (SMF), termed a magnetic band (Mb). To examine the effect of the Mb on wound healing, full-thickness 15 × 35 mm excision wounds were surgically created on the dorsum of rats. An elastic and contractile band (nontreatment), or one neodymium magnet (Nd-1) or two magnets with an elastic and contractile band (Nd-2) were topically applied to the wound daily and the wound size was measured from day 1 to 7 after surgery. Nd-2 showed a significant (95%) reduction in the wound size on day 3. Histological analysis showed that proinflammatory cytokine levels were diminished by Nd-2, and granulation tissue and microvessels were increased compared with those in the sham group. During Mb-induced wound healing, apoptosis was significantly reduced and matrix remodeling-related factors were initially regulated. The results suggest that combination therapy comprising an SMF and an elastic and contractile band could be a promising tool to heal cutaneous wounds rapidly.

Hierarchical Stereo Matching in Two-Scale Space for Cyber-Physical System.

Dense disparity map estimation from a high-resolution stereo image is a very difficult problem in terms of both matching accuracy and computation efficiency. Thus, an exhaustive disparity search at full resolution is required. In general, examining more pixels in the stereo view results in more ambiguous correspondences. When a high-resolution image is down-sampled, the high-frequency components of the fine-scaled image are at risk of disappearing in the coarse-resolution image. Furthermore, if erroneous disparity estimates caused by missing high-frequency components are propagated across scale space, ultimately, false disparity estimates are obtained. To solve these problems, we introduce an efficient hierarchical stereo matching method in two-scale space. This method applies disparity estimation to the reduced-resolution image, and the disparity result is then up-sampled to the original resolution. The disparity estimation values of the high-frequency (or edge component) regions of the full-resolution image are combined with the up-sampled disparity results. In this study, we extracted the high-frequency areas from the scale-space representation by using difference of Gaussian (DoG) or found edge components, using a Canny operator. Then, edge-aware disparity propagation was used to refine the disparity map. The experimental results show that the proposed algorithm outperforms previous methods.

Flow cytometric characterization of hemocytes of the solitary ascidian, Halocynthia roretzi.

Internal defense of ascidians relies, at least partially, on cells circulating in body fluids and infiltrating in tissues, referred to as hemocytes, although structure and composition of ascidian hemocytes still remain unclear. In the present study, we investigated hemocyte types and their functions of the solitary ascidian Halocynthia roretzi using flow cytometry. Based on morphology, cellular activities and intracellular parameters from the flow cytometry, we identified eight hemocyte types including, three granulocytes (Gr-1, Gr-2, and Gr-3), 4 hyalinocytes (Hy-1, Hy-1', Hy-2, and Hy-3) and lymphocyte-like (Ly-like) cells. The granulocyte Gr-1 accounted for 30% of the total circulating hemocytes and exhibited highest density of lysosomes and oxidative activity. Gr-1 was deeply involved in phagocytosis and degradation of foreign material. Hyalinocytes consist of two main populations, Hy-1 and Hy-2, and each accounted for 30% of the circulating hemocyte. Hy-1 displayed lysosomal content, an inducible oxidative activity, and no proteases, while Hy-2 expressed highest density of intracellular proteases, no lysosomes and a low oxidative activity. It was believed that Hy-2 may represent an important link between cellular and humoral immune reactions. Hy-1 did not show phagocytosis activity. Hy-3 and the Ly-like cells presented a similar profile except for their size and complexity, and Hy-3 may represent an intermediate differentiation/maturation step between Ly-like cells and other hemocyte populations. This first characterization of the hemocyte populations of H. roretzi provides a solid basis to investigate further their respective roles and functions in physiological and pathological contexts.

First report of Perkinsus honshuensis in the variegated carpet shell clam Ruditapes variegatus in Korea.

The recent discovery of Perkinsus honshuensis, a new Perkinsus species infecting Manila clams Ruditapes philippinarum (Sowerby, 1852), in Japan, suggested that, based on proximity, P. honshuensis could also be in Korean waters, where to date, P. olseni was believed to be the only Perkinsus species present. Perkinsus sp. infections consistently occurred among Ruditapes variegatus clams on a pebble beach on Jeju Island, off the south coast of Korea. The typical 'signet ring' morphology of the parasite was observed in the connective tissue of the digestive gland, and infection intensity was comparatively low (3.3 × 103 ± 1.2 × 104 to 1.3 × 104 ± 6.1 × 104 cells g-1 gill weight). Further DNA analyses of internal transcribed spacer (ITS-1, 5.8S and ITS-2) and non-transcribed spacer (NTS) regions of the parasite showed 98.9-99.8 and 98.5-99.5% similarity to those of P. honshuensis from Japan, respectively. Phylogenetic analyses using ITS and NTS sequences indicated that Perkinsus sp. from Jeju formed a highly supported clade with P. honshuensis. This is the first report of P. honshuensis infections in clams in Korean waters and the first report of R. variegatus as a host for that parasite.

Assessment of the fitness of the mussel Mytilus galloprovincialis two years after the Hebei Spirit oil spill.

In December 2007, >150km of the West coast of Korea were heavily polluted by crude oil leaked from the oil tanker Hebei Spirit, leading to mass mortality of bivalve mollusks on the intertidal areas. Two years after, mussels Mytilus galloprovincialis were collected from two impacted sites to investigate sub-lethal effects of the oil spill. Tissue content in polycyclic aromatic hydrocarbons (PAHs), hemocyte parameters, reproductive status and energetic reserves were analyzed. PAHs in tissues of mussels as well as hemocyte parameters were not different between impacted and control sites. Energetic reserves were altered in mussels from the impacted sites. Glycogen content remained low at polluted sites, whatever the season. Two years after the Hebei Spirit oil spill, mussels then presented altered energetic metabolism. Further investigations are thus warranted to monitor the sustainability of mussel populations on the oil spilled West coast of Korea.

Substantial changes in hemocyte parameters of Manila clam Ruditapes philippinarum two years after the Hebei Spirit oil spill off the west coast of Korea.

Two years after the Hebei Spirit oil spill occurred off the west coast of Korea, we determined sub-lethal effects of the spilled oil on hemocyte parameters of Ruditapes philippinarum in the damaged areas. Clams in the spilled sites displayed unusually high proportion of granulocytes, which may result in higher phagocytosis capacity and reactive oxygen species production. Hemocytes in clams from the polluted sites also displayed less DNA damage and mortality than in the control site, possibly due to a faster phagocytosis of the impaired cells. Glycogen, the major energetic reserve, was depleted in clams from the spilled sites, potentially due to energetic consumption for maintenance of a large pool of granulocytes, detoxification processes and oxidative stress. Modified hemocyte parameters in clams in the spilled area, may reflect sub-lethal physiological stresses caused by the residual oils in the sediment, in conjunction with environmental modifications such as food availability and pathogens pattern.

First report of Urosporidium sp., a haplosporidian hyperparasite infecting digenean trematode Parvatrema duboisi in Manila clam, Ruditapes philippinarum on the west coast of Korea.

In this study, we first report on the occurrence of Urosporidium sp., a haplosporidian hyperparasite infecting the trematode, Parvatrema duboisi, which parasitizes Manila clams, Ruditapes philippinarum on the west and south coasts of Korea. The larval P. duboisi infected by the sporocyst stage of Urosporidium sp. demonstrated numerous small yellowish spores in their tissues. The heavily infected metacercariae exhibited degenerate bodies and the larvae were often motionless. Clams heavily infected by the metacercariae of P. duboisi also displayed abnormal golden spots on the mantle tissue. In histology, different life stages of Urosporidium sp. could be identified, including the uni-nucleate, plasmodial, sporogonic stages and the acid fast mature spores released from the cyst. In scanning electron microscopy (SEM), the mature spore exhibited a semi-circular rim around the apical end and the orifice was covered internally with a flap. Loop-like filaments ornamentation was also identified from Urosporidium sp. in SEM, suggesting that Urosporidium sp. found in this study is a new member in the genus. Prevalence of Urosporidium sp.-infected trematodes in this study ranged from 2.5% to 24.0% in April 2010 and the infection was observed from 8 sampling sites out of the 26 sites surveyed on the west and south coasts.

The known and unknown sources of reactive oxygen and nitrogen species in haemocytes of marine bivalve molluscs.

Reactive oxygen and nitrogen species (ROS and RNS) are naturally produced in all cells and organisms. Modifications of standard conditions alter reactive species generation and may result in oxidative stress. Because of the degradation of marine ecosystems, massive aquaculture productions, global change and pathogenic infections, oxidative stress is highly prevalent in marine bivalve molluscs. Haemocytes of bivalve molluscs produce ROS and RNS as part of their basal metabolism as well as in response to endogenous and exogenous stimuli. However, sources and pathways of reactive species production are currently poorly deciphered in marine bivalves, potentially leading to misinterpretations. Although sources and pathways of ROS and RNS productions are highly conserved between vertebrates and invertebrates, some uncommon pathways seem to only exist in marine bivalves. To understand the biology and pathobiology of ROS and RNS in haemocytes of marine bivalves, it is necessary to characterise their sources and pathways of production. The aims of the present review are to discuss the currently known and unknown intracellular sources of reactive oxygen and nitrogen species in marine bivalve molluscs, in light of terrestrial vertebrates, and to expose principal pitfalls usually encountered.

Comparative study on the hemocytes of subtropical oysters Saccostrea kegaki (Torigoe & Inaba, 1981), Ostrea circumpicta (Pilsbry, 1904), and Hyotissa hyotis (Linnaeus, 1758) in Jeju Island, Korea: morphology and functional aspects.

We first characterized the morphology and immune-related activities of hemocytes in the subtropical oysters Saccostrea kegaki, Ostrea circumpicta, and Hyotissa hyotis using light microscopy and flow cytometry. Hemocytes of these three oyster species were classified into three main types: 1) granulocytes containing numerous granules in the cytoplasm, 2) hyalinocytes with no or fewer granules, and 3) blast-like cells characterized by the smallest size and very thin cytoplasm. The percentage of each hemocyte population was similar in all species; hyalinocytes were the most abundant cell in the hemolymph accounting for more than 59%, followed by granulocytes (23-31%) and blast-like cells (3-5%). The size of granulocytes of S. kegaki was smaller (P < 0.05) than those of O. circumpicta and H. hyotis. Light microscopy also allowed the description of vacuolated cells characterized by large vacuoles in the cytoplasm. Flow cytometry analysis confirmed that the granulocytes of the three oyster species were the major hemocytes engaged in cellular defense with the largest lysosome content, and the most active phagocytosis activity and oxidative activity, as was previously reported in several marine bivalves. Phagocytic activity was the lowest in S. kegaki hemocytes, and PMA-stimulated oxidative activity was the lowest in H. hyotis hemocytes. Our results provide the basic information of hemocytes population of three subtropical oysters for further investigations associated with various environmental disease stresses.

Molecular and histological identification of Marteilioides infection in Suminoe Oyster Crassostrea ariakensis, Manila Clam Ruditapes philippinarum and Pacific Oyster Crassostrea gigas on the south coast of Korea.

The oyster ovarian parasite Marteilioides chungmuensis has been reported from Korea and Japan, damaging the oyster industries. Recently, Marteilioides-like organisms have been identified in other commercially important marine bivalves. In this study, we surveyed Marteilioides infection in the Manila clam Ruditapes philippinarum, Suminoe oyster Crassostrea ariakensis, and Pacific oyster Crassostrea gigas, using histology and Marteilioides-specific small subunit (SSU) rDNA PCR. The SSU rDNA sequence of M. chungmuensis (1716 bp) isolated from C. gigas in Tongyoung bay was 99.9% similar to that of M. chungmuensis reported in Japan. Inclusions of multi-nucleated bodies in the oocytes, typical of Marteilioides infection, were identified for the first time in Suminoe oysters. The SSU rDNA sequence of a Marteilioides-like organism isolated from Suminoe oysters was 99.9% similar to that of M. chungmuensis. Marteilioides sp. was also observed from 7 Manila clams of 1840 individuals examined, and the DNA sequences of which were 98.2% similar to the known sequence of M. chungmuensis. Unlike Marteilioides infection of Pacific oysters, no remarkable pathological symptoms, such as large multiple lumps on the mantle, were observed in infected Suminoe oysters or Manila clams. Distribution of the infected Manila clams, Suminoe oysters and Pacific oysters was limited to small bays on the south coast, suggesting that the southern coast is the enzootic area of Marteilioides infection.

Comparative study on the toxic effects of red tide flagellates Heterocapsa circularisquama and Chattonella marina on the short-necked clam (Ruditapes philippinarum).

Heterocapsa circularisquama showed much higher toxic effects on short-necked clams than Chattonella marina. Clams exposed to H. circularisquama exhibited morphological changes concomitant with an accumulation of mucus-like substances in the gills, a profound reduction in filtration activity, and lysosomal destabilization in hemocytes. Chattonella marina was less effective than H. circularisquama, and Heterocapsa triquetra was almost harmless in all these criteria. These results suggest that H. circularisquama exerted its lethal effect on short-necked clams through gill tissue damage and subsequent induction of physiological stress.

First characterisation of the populations and immune-related activities of hemocytes from two edible gastropod species, the disk abalone, Haliotis discus discus and the spiny top shell, Turbo cornutus.

The disk abalone Haliotis discus discus and the spiny top shell Turbo cornutus are edible gastropod species of high economic value, mainly in Asia. Mortality outbreaks and variations in worldwide stock abundance have been reported and suggested to be associated, at least in part, with pathogenic infections. Ecology, biology and immunology of both species are currently not well documented. The characterisation of the immune systems of these species is necessary to further assess the responses of H. discus discus and T. cornutus to environmental, chemical and disease stresses. In the present study, we investigated the morphology and immune-related activities of hemocytes in both species using light microscopy and flow cytometry. Two types of hemocytes were identified in the disk abalone hemolymph, blast-like cells and hyalinocytes; whereas four main hemocyte types were distinguished in the spiny top shell, blast-like cells, type I and II hyalinocytes, and granulocytes. Flow cytometric analysis also revealed differences between cell types in immune-related activities. Three subsets of hemocytes, defined by differing lysosomal characteristics, were observed in the hemolymph of the spiny top shell, and only one in the disk abalone. Phagocytic activity was higher in H. discus discus hemocytes than in T. cornutus hemocytes, and the kinetics of PMA-stimulated oxidative activity was different between hemocytes of the disk abalone and the spiny top shell. Finally our results suggest for the first time a predominant mitochondrial origin of oxidative activity in gastropod hemocytes.