Multicomponent magnetizations in Nipissing diabase near Temagami, Ontario, and structural and thermal history of the Grenville Front

1989 ◽  
Vol 26 (3) ◽  
pp. 467-478 ◽  
Author(s):  
Hironobu Hyodo ◽  
David J. Dunlop
Keyword(s):  
Country Rock ◽  
Unknown Origin ◽  
Vertical Axis ◽  
Hydrothermal Activity ◽  
Natural Remanent Magnetization ◽  
Lake Area ◽  
Block Rotation ◽  
History Of ◽  
Tectonic Rotation ◽  
Late Stages

The Nipissing diabase (ND), sampled 2 km northwest of the Grenville Front near Temagami, Ontario, has four distinct components of natural remanent magnetization (NRM). The lowest unblocking temperature (TUB) component is attributed to the present Earth's field, whereas the second lowest TUB component is due to overprinting during the late stages of the Grenvillian Orogeny (~900 Ma). Similar Grenvillian overprint directions of NRM are found in Archean (~2600 Ma) country rock. The second highest TUB component (B) has an unknown origin. Low-temperature demagnetization (LTD) reveals that this component is significantly contaminated by overlap with the Grenvillian overprint and with the highest TUB component (A). If the A NRM is primary, its direction should agree with previously published ND poles after structural correction for subvertical tilting of sites. However, the structurally corrected A direction does not agree with known ND primary directions without additional rotation about a vertical axis. This may indicate sequential block rotation and tilting or could be caused by a single tectonic rotation about an inclined axis. The ND in the Temagami area shows a variety of characteristic magnetizations, which may reflect a complicated structural history and (or) hydrothermal activity before Grenvillian uplift, whereas west of Lake Temagami and in the Wanapitei Lake area ND results agree with the previously reported N1 paleopole. This contrast suggests quite different tectonic histories east and west of Lake Temagami.

A 200-Year History of the Study of Childhood Language Disorders of Unknown Origin: Changes in Terminology

2020 ◽  
Vol 5 (1) ◽  
pp. 6-11 ◽  
Author(s):  
Laurence B. Leonard
Keyword(s):  
Language Impairment ◽  
Specific Language Impairment ◽  
Scientific Literature ◽  
Language Disorder ◽  
Language Disorders ◽  
Unknown Origin ◽  
Developmental Language Disorder ◽  
The Past ◽  
History Of ◽  
The Many

Purpose The current “specific language impairment” and “developmental language disorder” discussion might lead to important changes in how we refer to children with language disorders of unknown origin. The field has seen other changes in terminology. This article reviews many of these changes. Method A literature review of previous clinical labels was conducted, and possible reasons for the changes in labels were identified. Results References to children with significant yet unexplained deficits in language ability have been part of the scientific literature since, at least, the early 1800s. Terms have changed from those with a neurological emphasis to those that do not imply a cause for the language disorder. Diagnostic criteria have become more explicit but have become, at certain points, too narrow to represent the wider range of children with language disorders of unknown origin. Conclusions The field was not well served by the many changes in terminology that have transpired in the past. A new label at this point must be accompanied by strong efforts to recruit its adoption by clinical speech-language pathologists and the general public.

scholarly journals Inference of the worldwide invasion routes of the pinewood nematodeBursaphelenchus xylophilususing approximate Bayesian computation analysis

2018 ◽  
Author(s):  
Sophie Mallez ◽  
Chantal Castagnone ◽  
Eric Lombaert ◽  
Philippe Castagnone-Sereno ◽  
Thomas Guillemaud
Keyword(s):  
Approximate Bayesian Computation ◽  
Unknown Origin ◽  
Bayesian Computation ◽  
Pinewood Nematode ◽  
Invasion Routes ◽  
The Usa ◽  
History Of ◽  
Abc Method ◽  
Approximate Bayesian ◽  
Inference Methods

ABSTRACTPopulation genetics have been greatly beneficial to improve knowledge about biological invasions. Model-based genetic inference methods, such as approximate Bayesian computation (ABC), have brought this improvement to a higher level and are now essential tools to decipher the invasion routes of any invasive species. In this paper, we performed ABC analyses to shed light on the pinewood nematode (PWN) worldwide invasion routes and to identify the source of European populations. Originating from North America, this microscopic worm has been invading Asia since 1905 and Europe since 1999, causing tremendous damage on pine forests. Using microsatellite data, we demonstrated the existence of multiple introduction events in Japan (one involving individuals originating from the USA and one involving individuals with an unknown origin) and China (one involving individuals originating from the USA and one involving individuals originating from Japan). We also found that Portuguese samples had an American origin. Although we observed some discrepancies between descriptive genetic methods and the ABC method, which are worth investigating and are discussed here, the ABC approach definitely helped clarify the worldwide history of the PWN invasion.

The geochemical evolution of Nb–Ta–Sn oxides from pegmatites of the Cape Cross–Uis pegmatite belt, Namibia

2018 ◽  
Vol 83 (02) ◽  
pp. 161-179 ◽  
Author(s):  
Warrick C. Fuchsloch ◽  
Paul A. M. Nex ◽  
Judith A. Kinnaird
Keyword(s):  
Country Rock ◽  
Minor Element ◽  
Aqueous Fluid ◽  
Geochemical Evolution ◽  
Rare Element ◽  
Fractionation Process ◽  
North Central ◽  
Mineral Inclusions ◽  
Late Stages ◽  
Zonation Patterns

AbstractThe Cape Cross–Uis pegmatite belt, Damara Orogen, north-central Namibia hosts multiple Ta–Nb- and Sn-oxide-bearing pegmatites. Columbite-group minerals, tapiolite, cassiterite and minor ixiolite and wodginite occur in abundance within pegmatites and display various compositional and internal structural mineralogical variations. Ta–Nb oxides display various zonation patterns indicative of multiple crystallisation phases, whereas cassiterite is dominantly homogeneous with minor euhedral columbite-group mineral inclusions. Ta–Nb oxides are mostly rich in Fe, with fractionation patterns in the columbite quadrilateral being sub parallel to the Ta/(Ta + Nb) axis; increasing Ta/(Ta + Nb) with little change in Mn/(Mn + Fe), which is consistent with classical trends in beryl-to-spodumene rare-element pegmatites. In addition, these trends suggest that co-crystallising minerals compete with Ta–Nb oxides for elements such as Mn, preventing Ta–Nb oxides from attaining Mn-rich compositions during the fractionation process. Cassiterite shows similar fractionation patterns with Fe > Mn and notable increases in the Ta content. Minor-element substitution in Ta–Nb oxides shows sharp decreases with increasing fractionation supporting the hypothesis that newly stabilised co-occurring minerals compete with columbite-group minerals for certain elements. Tapiolite shows the same minor-element trend, however, only for Sn and Ti suggesting cassiterite was a dominant competing mineral. Although crystallisation of Ta–Nb oxides from an aqueous fluid at the late-stages of pegmatite genesis is highly debated, significantly elevated Ta contents in metasomatised country rock, compared to unaltered country rock, may give new insight, suggesting that Ta may indeed partition into, and be transported by, an exsolved aqueous fluid. However, further studies of the country rock metasomatic contacts are required as currently the dataset is limited. The degree of fractionation as depicted by Ta–Nb and Sn oxides within pegmatites, indicate that a zonation from primitive to evolved pegmatites surrounding granites is not present and that pegmatites are probably not related to granites in the typical parent–daughter relationship.

scholarly journals FTIR-Based Crystallinity Assessment of Aragonite–Calcite Mixtures in Archaeological Lime Binders Altered by Diagenesis

Minerals ◽  
2019 ◽  
Vol 9 (2) ◽  
pp. 121 ◽  
Author(s):  
Michael Toffolo ◽  
Lior Regev ◽  
Stéphan Dubernet ◽  
Yannick Lefrais ◽  
Elisabetta Boaretto
Keyword(s):  
Unknown Origin ◽  
Infrared Light ◽  
Infrared Spectrometry ◽  
Atomic Order ◽  
Range Atomic Order ◽  
Mechanisms Of Formation ◽  
History Of ◽  
Lime Plaster ◽  
Archaeological Sediments ◽  
Diagenetic History

Lime plaster and mortar are pyrotechnological materials that have been employed in constructions since prehistoric times. They may nucleate as calcite and/or aragonite under different environmental settings. In nature, aragonite and calcite form through biogenic and geogenic processes that lead to different degrees of atomic order. The latter is a result of defects in the crystal lattice, which affect the properties of crystals, including their interaction with infrared light. Using Fourier transform infrared spectrometry (FTIR) with the KBr pellet method, it is possible to exploit these differences and assess the degree of atomic order of aragonite and calcite crystals and thus their mechanisms of formation. Here we use FTIR to characterize the degree of short-range atomic order of a pyrogenic form of aragonite recently observed in experimental and archaeological lime binders. We show that pyrogenic aragonite has a unique signature that allows its identification in archaeological sediments and lime binders of unknown origin. Based on these results, we developed a new FTIR-based method to assess the integrity and degree of preservation of aragonite and calcite when they occur together in the same material. This method allowed a better assessment of the diagenetic history of an archaeological plaster and finds application in the characterization of present-day conservation materials, such as lime plaster and mortar, where different polymorphs may nucleate and undergo recrystallization processes that can alter the mechanical properties of binders.

scholarly journals Isolated tuberculosis of the spleen presenting with fever of unknown origin in a vaccinated child

2020 ◽  
Vol 2020 (10) ◽  
Author(s):  
Ameer Kakaje ◽  
Yousef Mahmoud ◽  
Osama Hosam Aldeen ◽  
Othman Hamdan
Keyword(s):  
Rare Case ◽  
Causes Of Death ◽  
Fever Of Unknown Origin ◽  
Unknown Origin ◽  
Bacillus Calmette Guerin ◽  
Immunocompetent Child ◽  
Mild Anaemia ◽  
History Of ◽  
Unnecessary Procedures ◽  
Immunocompromised Status

Abstract Tuberculosis (TB) is one of the top 10 causes of death worldwide and is more common in developing countries. Isolated splenic TB is typically found in trauma, miliary TB and immunocompromised status. We present a very rare case of an immunocompetent child with an isolated primary TB in the spleen. The child only had fever of unknown origin (FUO), and mild anaemia. The diagnosis was not made until splenectomy was performed. The patient took the quadruple therapy for TB, and follow-ups showed no recurrence. This case is unique because this child was immunocompetent with no history of trauma or active TB. TB diagnosis should never be ignored in FUO as this might prevent unnecessary procedures to the patient. Although the child was vaccinated with Bacillus Calmette–Guérin that usually protects against severe TB in first 5 years of life, it did not prevent from affecting the spleen.

scholarly journals Feline meningioma with extensive nasal involvement

2019 ◽  
Vol 5 (1) ◽  
pp. 205511691983373
Author(s):  
Jorge Pérez-Accino ◽  
Anna Suñol ◽  
Elizabeth Munro ◽  
Adrian W Philbey ◽  
Katia Marioni-Henry
Keyword(s):  
Differential Diagnosis ◽  
Nasal Cavity ◽  
Frontal Lobe ◽  
Unknown Origin ◽  
Mass Effect ◽  
Cribriform Plate ◽  
Case Summary ◽  
Histopathological Evaluation ◽  
Axial Mass ◽  
History Of

Case summary A 9-year-old male neutered domestic longhair cat was presented with a 3 week history of lethargy and pain of unknown origin. A large extra-axial mass was demonstrated on MRI of the head, with cribriform plate destruction, extensive nasal invasion and intracranial expansion, producing a severe mass effect. The mass was isointense on T1-weighted imaging, predominantly hypointense with some hyperintense areas on T2-weighted imaging and fluid attenuation inversion recovery, markedly contrast enhancing, and caused transtentorial and cerebellar herniation. Histopathological evaluation confirmed a transitional (mixed) meningioma. Relevance and novel information To our knowledge this is the first report of a meningioma with extensive nasal involvement in a cat. Based on this case, meningioma should be considered as a differential diagnosis for tumours involving the nasal cavity and frontal lobe with cribriform plate destruction.

scholarly journals Cryotherapy for Lichen Striatus in an Adult – a Case Report

2015 ◽  
Vol 7 (4) ◽  
pp. 163-171
Author(s):  
Slobodan Stojanović ◽  
Marina Jovanović ◽  
Nada Vučković
Keyword(s):  
Inflammatory Infiltrate ◽  
Unknown Origin ◽  
Skin Condition ◽  
First Year ◽  
Linear Distribution ◽  
Lichen Striatus ◽  
Full Resolution ◽  
Lines Of Blaschko ◽  
History Of ◽  
First Year Of Life

Abstract Lichen striatus (linear lichenoid dermatosis) is an uncommon, self-limited, inflammatory, linear skin condition of unknown origin. The causes of linear distribution are unknown, though the pattern of lichen striatus (LS) mostly follows the lines of Blaschko (BL). The condition most commonly occurs in children between 5 and 15 years of age, usually after the first year of life. We report a 27-year-old, otherwise healthy flight attendant with LS whose diagnosis was based on: the history of sudden appearance and rapid linear spread of lesions; clinical presentation of small pink, coalescing scaly papules without umbilication or Wickham’s striae, linear distribution following one BL down a lower limb to the ankle, with a band broadening into plaque on the left buttock; histology showed some hyperkeratosis, lichenoid dermatitis similar to lichen planus, but with the presence of inflammatory infiltrate in the papillary dermis and also deeper in the perifollicular region. The inflammatory infiltrate consisted mainly of limphocytes, with some melanophages and histiocytes. There is no standard treatment for LS, and it is given for cosmetic or psychological reasons only, as we have done in our patient due to slight pruritus and occupational reasons. With regard to her occupational demands, in order to achieve satisfying results, she was successfully treated with cryotherapy, which she tolerated well, without any side effects. Cryotherapy was performed twice, with a two-week interval. Full resolution was achieved twelve weeks after cryotherapy. In conclusion, we present an adult female who developed lichen striatus suddenly three months after delivery and was successfully treated with cryotherapy.

scholarly journals Mineralogy of an Appinitic Hornblende Gabbro and Its Significance for the Evolution of Rising Calc-Alkaline Magmas

Minerals ◽  
2020 ◽  
Vol 10 (12) ◽  
pp. 1088
Author(s):  
Georgia Pe-Piper
Keyword(s):  
Oxygen Fugacity ◽  
Gradual Increase ◽  
Country Rock ◽  
Ti Oxides ◽  
Hornblende Gabbro ◽  
Reducing Conditions ◽  
History Of ◽  
Alkaline Magmas ◽  
The Relationship ◽  
Hydrous Magma

The magmatic and sub-solidus evolution of calcic amphiboles and Fe–Ti oxides was investigated in the Neoproterozoic Frog Lake pluton, Nova Scotia, Canada, in order to understand the relationship between the history of hydrous magma and the resulting mineralogy. The pluton occurs as sheet-like bodies of hornblende gabbro and hornblendite, with lesser tonalite dykes and granite bodies, interlayed with screens of medium-grade metamorphic country rock. Small, diffuse clots of felsic minerals are present in the gabbro. The subsolidus growth of actinolite occurs in early clinopyroxenes and amphiboles. Ilmenite is the dominant Fe–Ti oxide, as interstitial magmatic crystals. The increase of Mn towards the margin of the ilmenite crystals indicates a gradual increase in oxygen fugacity with time, leading to the precipitation of titanite and ferrohypersthene. The replacement of titanite by ilmenite and ilmenite lamellae in the amphiboles suggests subsequent reducing conditions during the sub-solidus crystallisation. The gabbros in the coeval, but apparently shallower, Jeffers Brook granodiorite laccolith have dominant magnetite and Mg-rich subsolidus amphiboles, which are indicative of high oxygen fugacity. The differences between the two plutons suggest that there was a greater flux of hydrothermal water through the sheet-like architecture of the Frog Lake pluton.

Spontaneous bilateral internal jugular vein thrombosis: a sign of metastasis

2004 ◽  
Vol 118 (7) ◽  
pp. 570-572 ◽  
Author(s):  
P.P. Cheang ◽  
J. Fryer ◽  
O. Ayoub ◽  
V. Singh
Keyword(s):  
Internal Jugular Vein ◽  
Jugular Vein ◽  
Unknown Origin ◽  
Short History ◽  
Jugular Vein Thrombosis ◽  
Neck Stiffness ◽  
Vein Thrombosis ◽  
Wide Range ◽  
Internal Jugular Vein Thrombosis ◽  
History Of

Head and neck swellings are common referrals to the otolaryngology department, with a wide range of aetiologies. Internal jugular vein thrombosis presenting as swelling in the neck is a rare occurrence. The authors report a case of bilateral internal jugular vein thrombosis secondary to malignant lymphadenopathy of unknown origin. The patient presented with a short history of a diffuse swelling in the neck with neck stiffness. Examination revealed palpable cervical and axillary lymphadenopathy. Causes of spontaneous internal jugular vein thrombosis were discussed.

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