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We report that high-Mg calcite spherulites can undergo a coarsening process to form calcareous spicules of ∼30 microns in width and several hundred microns in length after an aging process in air for a prolonged period. During the aging process, the crystallinity of the calcitic structure has been improved substantially with a significant migration of Mg ions toward the mineral surface. In a thin-foil sample of the spicule aged for 20 months, nanocrystallites of magnesite with minor substitution level of Ca ions have been found near the surface of the spicule.

X-ray micro-computed tomography (micro-CT) is used to resolve the detailed internal architecture of the siliceous skeletons of two well-preserved middle Cambrian (Miaolingian Series) radiolarians from the Inca Formation of the Georgina Basin, Australia. Digital dissections of specimens of Archeoentactinia incaensis and A. tetractinia reveal for the first time that both are exclusively composed of tetractine spicules. A basal layer consisting of robust spicules together with an interwoven meshwork of smaller spicules is observed in both micro-CT models. Detailed structural analysis with the aid of a digitally inserted artificial sphere shows that the framework spicules are likely to have been added one by one as the radiolarian cell enlarged. The timing of spicule genesis may be an important factor controlling the morphology of different groups of spicular radiolarians. Observation of these fundamental skeletal structures suggests that the type genus of Archeoentactiniidae Archeoentactinia belongs to Echidninidae; thus, Archeoentactiniidae is a junior synonym of Echidninidae.

Maldivea Gerlach, 1962 is a possible endemic genus of the Maldivian archipelago for which only M. xarifae Gerlach, 1962 has been described so far. A new species of this genus, M. complexa n.sp., was recently found in Felidhoo atoll. It reveals a more complex structure of gubernaculum than in type species which appears to be divided into two pieces: one is a sort of long wing in the ventral part of the spicule and the other one, more complex, is characterized by several curved stripes which envelop the dorsal side of the spicule distal part. According to the present considerations, diagnoses of Paroxystomininae and Maldivea are emended.

SummaryCryptaphelenchus baujardin. sp. is described and illustrated based on two populations from Golestan province, northern Iran. The new species is characterised by female and male body length of 224 (190-261) and 215 (195-229)μm, respectively, offset cephalic region with a shallow constriction, delicate stylet 6.6 (6.0-7.0)μm long, four incisures in the lateral field, presence of a rudimentary post-uterine sac in the female gonoduct, elongate-conoid female tail ending in an acute to finely rounded terminus, male tail conical, male with seven caudal papillae and delicate spicules. The new species shows a strong resemblance toC. varicaudatusandC. iranicus, but has a sclerotised mass near the tip of the spicule and an indistinct spermatheca. Phylogenetic analyses based on both partial SSU and LSU rDNA sequences confirm its status as a new taxon.

Ektaphelenchus koreanus n. sp. is isolated from Pinus packaging wood from Korea in Ningbo customs. The new species can be characterized by having four incisures in the lateral field, the excretory pore located posterior to nerve ring, female devoid of vulval flap, and having long post-vulval intestinal sac (55–106 μm), tail with a finely rounded terminus. Six caudal papillae in male and spicule short (12.7–13.7 μm), having broad squared to rounded condylus, triangular rounded rostrum, cucullus absent. Morphologically the species is most similar with E. berbericus, E. joyceae, E. oleae, E. ibericus, and E. taiwanensis but it can be differentiated by plenty of morphometrical and morphological characters. In addition, a morphometry table of Ektaphelenchus is also presented.

Silicatein is the main protein responsible for the formation of spicules, tiny structures that constitute the silica skeleton of marine demosponges (Phylum Porifera). A unique innovation in Porifera that evolved from the cathepsin L family of proteins, it has been reported that two amino acids (S and H) are necessary to form the catalytic triad (SHN) to enable silica condensation. However, a diversity of silicatein sequence variants has since been reported with a variable pattern of presence/absence across sponge groups. Variants containing CHN or C/SQN at the active site appear more common in sponges from the Haplosclerida. Here, we report the expression levels of five silicatein variants through different developmental stages in the haplosclerid Haliclona indistincta. All five silicatein variants were expressed at low levels in the free-swimming larvae, which lack spicules and expression significantly increased at the two developmental phases in which spicules were visible. At these two phases, silicateins of CHN and C/SQN types were much more highly expressed than the SHN type indicating a possible ability of active sites with these alternative amino acids to condense silica and a more complex evolutionary story for spicule formation in marine demosponges than previously understood.

Summary Bursaphelenchus rockyi n. sp., isolated in Peking, China, from peat moss imported from Russia, is described. It is characterised by a lateral field with four lines, excretory pore located at the base of the nerve ring or slightly posterior, spicule 15.9 (15.1-17.3) μm long along the chord and with high condylus and a rounded tip, rostrum triangular or conical with bluntly pointed tip, lamina curvature becoming more pronounced at 60% of total length, six caudal papillae with P3 and P4 adjacent to each other, bursa small, starting posterior to P4, vulval lips hemispherical and protruding, and tail conical with finely rounded or mucronated terminus. The new species belongs to the fungivorus-group and is most similar to B. arthuri, B. arthuroides, B. fungivorus and B. seani, but can be distinguished from related species by morphological and sequencing results.

A new nematode species of the genusPhasmarhabditiswas isolated from the body surface of a slug (Philomycus bilineatusBenson, PB). Morphological and molecular analyses confirmed this nematode as a new species. The nematode was namedPhasmarhabditis zhejiangensissp. nov. (Nematoda: Rhabditidae) and is dioecious. In males, the open bursa with genital papillae is characterized by the formula 1-1-1-2-1-3, and the spicule length is 58μm. In female, the vulva is located approximately in the middle of the body. The nematode belongs to papillosa group because of its tail shape pointed with filiform tip. The phasmids are rod-shaped. The posterior anus is slightly swollen.P.zhejiangensiswas further characterized by internal transcribed spacer (ITS), 18S rDNA and 28S rDNA sequences. After the sequencing results were compared with sequences available from the National Center for Biotechnology Information (NCBI), the maximum similarities of ITS, 18S and 28S sequences were 89.81%, 96.22% and 95.28%, respectively. Phylogenetic analyses placedPhasmarhabditis zhejiangensissp. nov. in the genusPhasmarhabditis.

ObjectiveIt was hypothesized that the respective protein profiles of bovine cartilage from sites of localized mild to moderate (GI to GII) degeneration versus adjacent sites of intact tissue would vary in accordance with the tissue microstructural changes associated with a pre-osteoarthritic state.MethodsA total of 15 bovine patellae were obtained for this study. Paired samples of tissue were collected from the lateral region of each patella. If the patella contained a site of degeneration, a paired tissue set involved taking one sample each from the degenerated site and the intact tissue adjacent to it. Sufficient tissue was collected to facilitate 2 arms of investigation: microstructural imaging and proteome analysis. The microstructural analysis used a bespoke tissue preparation technique imaged with differential interference contrast optical microscopy to assess fibrillar scale destructuring and underlying bone spicule formation. An iTRAQ-based proteome analysis was performed using liquid chromatography–tandem mass spectrometry to identify the differential levels of proteins across the intact and degenerated cartilage and further, the results were validated with multiple reaction monitoring assay.ResultsIn the healthy cartilage pairs, there was no significant variation in protein profiles between 2 adjacent sample sites. In pairs of tissue that contained a sample of GI/GII tissue, there were both significant microstructural changes as well as the difference in abundance levels of 24 proteins.ConclusionsFrom the known functions of the 24 proteins, found to be strongly aligned with the specific microstructural changes observed, a unique “proteins ensemble” involved in the initiation and progression of early cartilage degeneration is proposed.

The study presents species composition and abundance of nematodes of the family Capillariidae (Nematoda, Trichocephalida), parasitizing the domestic goose (Anser anser dom. Linnaeus, 1758) in Poltava region, Ukraine. Morphological specifics of adult specimens of collected helminths are examined and new data is obtained for species identification of Capillariidae considering their metric parameters. The pathogens of capillariasis in geese are represented by two species, Baruscapillaria anseris (Madsen, 1945) Moravec, 1982 and B. obsignata (Madsen, 1945) Moravec, 1982 with the former predominant. Prevalence of infection by B. anseris in domestic fowl was up to 46.8%, the abundance index reached 17.9 specimens. The proportion of geese infected with B. obsignata was 23.9%, and the abundance index was 3.8 specimens. Morphological study of the collected mature male and female nematodes revealed the significant similarity of both species in the general body structure and in identification characters: vulva and vagina structure in females, tail end, spicule and spicule sheath in males. Statistically significant differences were determined in the metric parameters of male and female B. anseris and B. obsignata nematodes. Those differences can be used to improve species identification. Males of B. anseris were larger than males of B. obsignata by 16 metric parameters including the length and width of body, spicule and spicule sheath, width of pseudobursa, and distance between the rays of pseudobursa. Females of B. anseris and B. obsignata were significantly different by seven metric parameters. By five parameters (length and width of various body regions) the B. anseris females were larger than B. obsignata. Metric parameters of the studied species are also of interest for taxonomic identification: the eggs of B. obsignata are longer and narrower than those of B. anseris.

Purpose To determine rate of bone spicule pigmentation appearance in patients with retinitis pigmentosa (RP). Design Retrospective, observational case series. Participants A total of 240 patients were analyzed for this study. Methods A retrospective analysis was conducted at the Electrodiagnostic Clinic at Columbia University Medical Center of all patients' medical records with a diagnosis of RP between July 2017 and January 2018. The medical records of these patients were analyzed to determine whether the patients presented with pigment migration on their first and last visit to our clinic. Among those who did not have bone spicule at first visit, we examined the time to appearance of newly formed bone spicule. The survival distribution was then estimated using the Kaplan-Meier estimator, where the event is bone spicule and time starts at first visit. Results From the 240 patients analyzed, 213 patients presented with intraretinal pigmentation on the first visit to our clinic, and 27 patients presented without intraretinal pigmentation. Of these 27 patients, 10 patients developed pigmentation by their follow-up, with a median time to appearance of bone spicule of 5.4 years from first visit, according to the Kaplan-Meier estimates. Conclusions The timeline of bone spicule pigment appearance in RP has important implications in the natural history characterization of disease progression and application as a biomarker for interventional trials.

Two new species of free-living marine nematodes of the genera Hopperia and Nemanema are described from the sublittoral sediment of the East China Sea. Hopperia macramphida sp. nov. is characterized by having large amphidial fovea with five turns; arcuate spicules with enlarged proximal end and central internal lamella extending one third of spicule length from proximal end; gubernaculum with bent apophyses, six papilliform precloacal supplements; and conico-cylindrical tail with swollen tip and terminal setae. Nemanema minutum sp. nov. is characterized by relatively smaller body size in the genus; large oval amphidial fovea; conical tail; slender spicules with alae and hooked proximal end; ring-like gubernaculum; and papilliform precloacal supplements with three short setae. An updated dichotomous key is provided for the 17 species of Hopperia.

Actinonema falciforme sp. nov. was discovered from the continental-shelf sediments of the East China Sea. It is characterized by six outer labial setae and four cephalic setae in one circle, complex and heterogeneous cuticular ornamentation with lateral differentiation, large and conspicuous amphideal fovea which is transversely ovalshaped, a single anterior testis, two opposed reflexed ovaries, falciform telamon (lateral pieces of gubernaculum), and the lack of spicule and gubernaculum. Within the genus Actinonema, only A. longicaudatum and the new species possess telamon and lack spicule and gubernaculum. Actinonema falciforme sp. nov. can be easily differentiated from A. longicaudatum by its much shorter body length, the peculiar shape of the telamon and a shorter tail.

Aphelenchoides manipurensis sp. nov. was collected from two different localities of Manipur. Though the specimens collected from two different areas show some variations in their morphology and morphometric data, it was taken as the same species due to similarities in many characters. A. manipurensis sp. nov. had females with L = 294.1–461.91 µm, a = 24.28–38.14, b = 6.3–8.65, b′ = 3.61–4.68, c = 12.47–16.46, c′ = 3–4.25, stylet = 10.38–13.84 µm, V = 68.88–71.69, post uterine sac = 25.98–53.63 µm long and two lateral lines. Males were common with spicule of 10.38–17.3 µm. Mucro were present in both sexes. Species presented with illustrations and morphometrics.

Four strains of entomopathogenic nematodes were isolated with a live trap method in southern Poland. The isolates were identified asSteinernema silvaticumbased on morphological, morphometric and molecular data. Infective juveniles of PolishS. silvaticumisolates differ in body length fromS. weiseri(951 vs 740 μm, respectively), and in the hyaline tail portion fromS. kraussei(48 vs 38%, respectively). First-generation males ofS. silvaticumare longer than those ofS. kraussei,S. weiseriandS. ichnusae(1829 vs 1400, 1180 and 1341 μm, respectively). Males ofS. silvaticumand a sister speciesS. krausseican be distinguished by the distance from the anterior end to the nerve ring (142 vs 105 μm), spicule (66 vs 49 μm) and gubernaculum length (45 vs 33 μm), and the presence of a mucron. The analysis of internal transcribed spacer (ITS), D2-D3 andcox1sequences of the tested nematodes revealed differences of 3–5%, 3% and 12–13%, respectively, fromS. krausseistrains. The phylogeny of both nuclear and mitochondrial genes indicated close relationships of the PolishS. silvaticumisolates withS. kraussei,S. oregonenseandS. cholashanense. The reproductive isolation of the studied isolates was confirmed by hybridization tests with other Europeanfeltiae–krausseigroup representatives. This study has supplemented the original description ofS. silvaticumwith morphological and morphometric characterization of the first-generation males and females. This is also the first molecular study of this species based on a multi-gene approach.

The biomineralization process offers novel principles for crystal engineering and solid-state chemistry, but to achieve this we must first understand how organisms such as the mollusk and sea urchin craft skeletal elements such as the shell and embryonic spicule, respectively. In vitro studies of mollusk- and sea urchin-associated proteins reveal that these proteins form hydrogel particles that control the nucleation process, assemble mineral nanoparticles, and modify the surfaces and interiors of existing crystals. However, visualization of these processes is hampered by destructive and invasive methods such as those used for conventional scanning electron microscopy/transmission electron microscopy. In this report we detail the novel use of microcomputerized X-ray tomography (μCT) imaging to nondestructively investigate the in vitro calcium carbonate mineralization process in the presence of a recombinant sea urchin spicule matrix protein, rSpSM50, and a recombinant mollusk shell nacre protein, rPif97. ...

Summary Bursaphelenchus geraerti n. sp., isolated in Tianjin, P.R. China, from packaging wood made of Pinus sp. imported from the United Arab Emirates, is described. It is characterised by the lateral field with three lines, a stylet 13-14 μm long with small basal swellings, excretory pore located posterior to nerve ring, spicule mitten-shaped, ventrally arcuate with lamina smoothly tapering towards distal tip, with a distinct bend near 60% of total length, condylus elongated with rounded tip, rostrum conical with finely rounded tip, and cucullus weakly developed or absent. The bursal flap is wide and spade-like with the posterior margin truncate or rounded and starts posterior to P6 gland papillae. A vulval flap is absent and the tail is conical, strongly ventrally curved with the terminus pointed and sometimes appearing as a mucron. The new species is characterised by morphological and molecular analysis and is close to B. decraemerae, B. gerberae and B. sakishimanus.

Bursaphelenchus decraemeraen. sp., isolated in Ningbo, China, from packaging wood made ofPinussp. imported from the USA, is described. It is characterised by the lateral field with three lines, a stylet 10-12 μm long with small basal swellings, excretory pore located 4-12 μm posterior to median bulb, spicule small, ventrally arcuate with lamina gradually tapering to distal tip, rostrum triangular pointed to conical, condylus elongated with bluntly rounded tip, and cucullus minute, barely visible. There are seven caudal papillae arranged as a single ventral precloacal papilla, one adcloacal pair and two postcloacal pairs. The bursal flap is narrow and oval. A small vulval flap is present in lateral view of the female and the tail is conical, strongly ventrally curved with the terminus finely pointed and sometimes appearing like a mucron. The new species is characterised by morphological and molecular analysis and is close toB. gerberaeandB. sakishimanus.

Gracilacus paralatescens n. sp., isolated in Anji County, Zhejiang Province, China from the rhizospheric soil of bamboo. The new species can be characterized by the female lateral field with three incisures, stylet 71.5 to 78.8 µm long, lip region truncated, excretory pore located anterior to basal knobs. Vulval lips non-protruding and without vulval flap, spermatheca large, elongated squarish shaped filled with sperms. Tail slender, relatively straight having wedge shape terminus. The spicule slender, slightly curved and 17.5 to 18.9 µm long. In the phylogenetic analysis based on 18S, D2-D3 of 28S and ITS regions of rDNA, the new species is clustered with Paratylenchid species having longer stylet length. Morphologically, the new species belongs to Group 9 of Paratylenchus sensu lato and is most similar to G. latescens. Gracilacus paralatescens n. sp., isolated in Anji County, Zhejiang Province, China from the rhizospheric soil of bamboo. The new species can be characterized by the female lateral field with three incisures, stylet 71.5 to 78.8 µm long, lip region truncated, excretory pore located anterior to basal knobs. Vulval lips non-protruding and without vulval flap, spermatheca large, elongated squarish shaped filled with sperms. Tail slender, relatively straight having wedge shape terminus. The spicule slender, slightly curved and 17.5 to 18.9 µm long. In the phylogenetic analysis based on 18S, D2-D3 of 28S and ITS regions of rDNA, the new species is clustered with Paratylenchid species having longer stylet length. Morphologically, the new species belongs to Group 9 of Paratylenchus sensu lato and is most similar to G. latescens.

In this study, two new species of the genus Callyspongia Duchassaing & Michelotti, 1864: Callyspognia pyeongdaensis sp. nov. and Callyspongia maraensis sp. nov. from Korea are described as new to science. All of the available information is presented in this study including the localities from which the species were collected and illustrations of spicule and skeleton. Keywords: Callyspongiidae, Callyspongia, Korea, New species, Sponge

Based on light and scanning electron microscopical studies, a new nematode parasite, Capillaria appendigera n. sp. (Capillariidae), is described from the intestine of the goldbanded jobfish Pristipomoides multidens (Day) (Perciformes, Lutjanidae) from the Arafura Sea West, off the northern coast of Australia. The new species, belonging to the subgenus Procapillaria Moravec, 1987, differs from other congeneric species from fishes mainly in the length (0.92–1.13 mm), shape and structure of the spicule, obtuse spines on the spicule sheath and the structure of eggs. It is characterised, in the male, by the presence of two well-developed dorsolateral caudal lobes, a pair of lateral papillae, a heavily sclerotised spicule with many rough transverse grooves covering almost the entice spicule surface (except for spicule ends), a spinose spicule sheath, and in the female, by a subterminal anus, mostly the presence of a large vulval appendage and by eggs (size 54–69 × 27–33 µm) encapsulated by a conspicuous light-coloured superficial layer. Capillaria appendigera n. sp. is the 12th nominal species of capillariids recorded from fishes in Australian waters and the second known capillariid species parasitising fishes of the perciform family Lutjanidae. In addition, four unidentifiable, morphologically different types of capillariid females, probably representing undescribed species, were recorded from the intestines of marine fishes off the northern coast of Australia: Capillariidae gen. sp. 1 and Capillariidae gen. sp. 2 from Lutjanus johnii (Bloch) and L. malabaricus (Bloch & Schneider), respectively (both Lutjanidae), Capillariidae gen. sp. 3 from Protonibea diacanthus (Lacepede) (Sciaenidae) and Capillariidae gen. sp. 4 from Rachycentron canadum (Linnaeus) (Rachycentridae).

In the sea urchin embryo spicule, there exists a proteome of >200 proteins that are responsible for controlling the mineralization of the spicule and the formation of a fracture-resistant composite. In this report, using recombinant proteins, we identify that two protein components of the spicule, SM30B/C and SM50, are hydrogelators. Because of the presence of intrinsic disorder and aggregation-prone regions, these proteins assemble to form porous mesoscale hydrogel particles in solution. These hydrogel particles change their size, organization, and internal structure in response to pH and ions, particularly Ca(II), which indicates that these behave as ion-responsive or “smart” hydrogels. Using diffusion-ordered spectroscopy NMR, we find that both hydrogels affect the diffusion of water, but only SM50 affects the diffusion of an anionic solute. Thus, the extracellular matrix of the spicule consists of several hydrogelator proteins which are responsive to solution conditions and can control the diffusion of water and solutes, and these proteins will serve as a model system for designing ion-responsive, composite, and smart hydrogels.

Procyrnea choique n. sp. is described from the lesser rhea, Rhea pennata d'Orbigny (Aves: Rheidae), from the Protected Natural Area Península Valdés, Chubut province, Argentina. The new species resembles P. ficheuri, P. murrayi, P. excisiformis, P. dollfusi, P. haliasturi, P. anterovulvata, P. graculae, P. brevicaudata, P. uncinipenis, P. javaensis, P. ameerae, P. ornata, P. aegotheles, P. spiralis, P. ruschii and P. aptera, mainly in the absence of lateral alae; but differs from its congeners by having a left spicule without barbs, the position of the vulva which is post-equatorial, the absence of lateral ridges, absent median precloacal papilla, asymmetrical caudal alae, males more than 6 mm long, left spicule 1 mm long and spicule ratio 1:3. Our results extend the taxonomy of Procyrnea Chabaud, 1958 and comprise the first report of a habronematid from R. pennata. A key to species of Procyrnea is presented. Fil: Bagnato, Estefanía. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico; Argentina Fil: Frixione, M.. Centro de Investigaciones Biológicas del Noroeste; México Fil: Digiani, Maria Celina. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. División de Zoología Invertebrados; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Cremonte, Florencia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico; Argentina

Summary Two isolates of Steinernema bertusi n. sp. were separately recovered from Tito, Mpumalanga, and Port Edward, Kwa Zulu Natal, South Africa. In this paper, we describe the isolates as a new entomopathogenic nematode (EPN) species using molecular and morphological methodologies. The new species belongs to the cameroonense-clade, which consists of nematodes only isolated from the African continent. Steinernema bertusi n. sp. is characterised by having the longest infective juvenile (IJ) for this clade at 716 (628-814) μm. The IJ is further characterised by a body diam. of 32 (28-36) μm and the pattern for the arrangement of the lateral ridges from head to tail is 2, 4, 5, 4, 2. The first-generation male spicule and gubernaculum length is 82 (72-88) μm and 63 (54-72) μm, respectively. Only 25% of the second-generation males possess a mucron. The first-generation females of S. bertusi n. sp. have a slightly protruding vulva, with double-flapped epiptygmata and a mucron at the posterior end. The new EPN species is most closely related to S. sacchari and is the sixth species to be included in the cameroonense-clade.

Alfv\'en waves are responsible for the transfer of magnetic energy in the magnetized plasma. They are involved in heating solar atmosphere and driving solar wind through various nonlinear processes. Since the magnetic field configurations directly affect the nonlinearity of Alfv\'en waves, it is important to investigate how they relate to the solar atmosphere and wind structure through the nonlinear propagation of Alfv\'en waves. In this study, we carried out the one-dimensional magnetohydrodynamic simulations to realize the above relation. The results show that when the nonlinearity of Alfv\'en waves in the chromosphere exceeds a critical value, the dynamics of the solar chromosphere (e.g., spicule) and the mass loss rate of solar wind tend to be independent of the energy input from the photosphere. In a situation where the Alfv\'en waves are highly nonlinear, the strong shear torsional flow generated in the chromosphere ``fractures'' the magnetic flux tube. This corresponds to the formation of chromospheric intermediate shocks, which limit the transmission of the Poynting flux into the corona by Alfv\'en waves and also inhibits the propagation of chromospheric slow shock., Comment: 25 pages, 22 figures, accepted for the publication in The Astrophysical Journal

Jet phenomena with a bright loop in their footpoint, called anemone jets, have been observed in the solar corona and chromosphere. These jets are formed as a consequence of magnetic reconnection, and from the scale universality of magnetohydrodynamics (MHD), it can be expected that anemone jets exist even in the solar photosphere. However, it is not necessarily apparent that jets can be generated as a result of magnetic reconnection in the photosphere, where the magnetic energy is not dominant. Furthermore, MHD waves generated from the photospheric jets could contribute to chromospheric heating and spicule formation; however, this hypothesis has not yet been thoroughly investigated. In this study, we perform 3D MHD simulation including gravity with the solar photospheric parameter to investigate anemone jets in the solar photosphere. In the simulation, jet-like structures were induced by magnetic reconnection in the solar photosphere. We determined that these jet-like structures were caused by slow shocks formed by the reconnection and were propagated approximately in the direction of the background magnetic field. We also suggested that MHD waves from the jet-like structures could influence local atmospheric heating and spicule formation., Comment: 34 pages, 21 figures, accepted for publication in PASJ

We succeeded in observing two large spicules simultaneously with the Atacama Large Millimeter/submillimeter Array (ALMA), the Interface Region Imaging Spectrograph (IRIS), and the Atmospheric Imaging Assembly (AIA) onboard the Solar Dynamics Observatory. One is a spicule seen in the IRIS Mg II slit-jaw images and AIA 304\AA\ images (MgII/304A spicule). The other one is a spicule seen in the 100GHz images obtained with ALMA (100GHz spicule). Although the 100GHz spicule overlapped with the MgII/304A spicule in the early phase, it did not show any corresponding structures in the IRIS Mg II and AIA 304A images after the early phase. It suggests that the spicules are individual events and do not have a physical relationship. To obtain the physical parameters of the 100GHz spicule, we estimate the optical depths as a function of temperature and density using two different methods. One is using the observed brightness temperature by assuming a filling factor, and the other is using an emission model for the optical depth. As a result of comparing them, the kinetic temperature of the plasma and the number density of ionized hydrogens in the 100GHz spicule are ~6800 K and 2.2 x 10^10 cm^-3. The estimated values can explain the absorbing structure in the 193A image, which appear as a counterpart of the 100GHz spicule. These results suggest that the 100GHz spicule presented in this paper is classified to a macrospicule without a hot sheath in former terminology., Comment: 8 pages, 4 figures, Accepted to ApJL