bluuebunny/crossref_metadata_2025_split huggingface dataset:
Decline of Fraxinus excelsior L. in parks of Saint Petersburg: Who is to blame – Hymenoscyphus fraxineus or Diplodia spp.?
Authors: Shabunin Dmitrii A. , Selikhovkin Andrey V. , Varentsova Elena Yu. , Musolin Dmitry L. 
Published: August 2021

Abstract
The weakening and decline of European ash Fraxinus excelsior L. and other ash species have been recorded at different locations in the suburbs of Saint Petersburg, Russia. During the summer of 2019 and spring of 2020, samples from leaves, petioles, and shoots were collected from the weakened and declining ash trees in three parks in Pushkin and Gatchina and maintained in humid chambers to induce the fructification of fungi. In total, 30 taxa of micromycetes belonging to 23 genera were identified using methods of light microscopy. Hymenoscyphus fraxineus, a putative agent of ash dieback, was not recorded in the samples collected in the crowns of trees, but only on the petioles of the fallen leaves in spring. Out of all the micromycetes recorded, only coelomycetes from the genus Diplodia Fr. (in particular, D. mutila) can damage the branches of ash trees and, thus, be considered pathogenic. It is likely that H. fraxineus opens “the entry of infection” and Diplodia spp. cause the major weakening and decline of branches. The data obtained can significantly change our understanding of the causes of ash dieback and possible methods of ash stand preservation. The reason for the low pathogenicity and activity of H. fraxineus, as well as the possible role of ascomycetes Diplodia spp. in the dieback of ash stands requires further research.
Forest cover dynamics of the Bazoy Siberian pine (Pinus sibirica Du Tour) forest from 1915 to 2015
Authors: Debkov Nikita , Sidorenkov Victor , Sidorenkova Elena , Sedykh Vladimir 
Published: August 2021

Abstract
The article considers the long-term (100 years) dynamics of the forest cover of the southernmost unit of Siberian pine forests on the West Siberian plain. A key feature of forest management is that Siberian pine seeds are a valuable food product and, when cutting forests, this tree species, as a rule, is preserved. The basis of the experimental data was the material of the national forest inventories of 1915, 1974 and 2015 for a total area of 1,420.41 ha. During the period from 1915 to 2015, the forested area changed slightly (96.2 and 94.0%), while the share of Siberian pine stands increased significantly from 48.4 to 58.7%. Grassy Siberian pine forests (32.1%) of optimal age (120–140 years), which are characterised by the best seed productivity and the largest share of Siberian pine in the community (77%), predominate. Basically, human economic activity results in an increase in the area of Siberian pine stands, when deciduous stands with Siberian pine undergrowth are used for fuel and as building material. A decrease in the area of Siberian pine forests occurs mainly under the impact of fires. In the conflagrations of 1915–1920, 7 to 38% of silver birch forests have no Siberian pine undergrowth and are considered long-term secondary communities. In the remaining area, the proportion of Siberian pine undergrowth is 20–30% with a density of 800–1200 seedlings ha−1, which is sufficient for the natural formation of Siberian pine forests.
Potential of ecological modelling and smart-drainage development for mitigating adverse effects of future global change-type droughts for the Estonian forest sector
Authors: George Jan-Peter , Lang Mait , Hordo Maris , Metslaid Sandra , Post Piia , Tamm Toomas 
Published: August 2021

Abstract
Global change-type droughts will become more frequent in the future and threaten forest ecosystems around the globe. A large proportion of the Estonian forest sector is currently subject to artificial drainage, which could probably lead to negative feedbacks when water supply falls short because of high temperatures and low precipitation during future drought periods. In this short article, we propose a novel research perspective that could make use of already gathered data resources, such as remote sensing, climate data, tree-ring research, soil information and hydrological modelling. We conclude that, when applied in concert, such an assembled dataset has the potential to contribute to mitigation of negative climate change consequences for the Estonian forest sector. In particular, smart-drainage systems are currently a rare phenomenon in forestry, although their implementation into existing drainage systems could help maintain the critical soil water content during periods of drought, while properly fulfilling their main task of removing excess water during wet phases. We discuss this new research perspective in light of the current frame conditions of the Estonian forest sector and resolve some current lacks in knowledge and data resources which could help improve the concept in the future.
An indirect approach to predict deadwood biomass in forests of Ukrainian Polissya using Landsat images and terrestrial data
Authors: Matsala Maksym , Myroniuk Viktor , Bilous Andrii , Terentiev Andrii , Diachuk Petro , Zadorozhniuk Roman 
Published: August 2021

Abstract
Spatially explicit and consistent mapping of forest biomass is one of the key tasks towards full and appropriate accounting of carbon budgets and productivity potentials at different scales. Landsat imagery coupled with terrestrial-based data and processed using modern machine learning techniques is a suitable data source for mapping of forest components such as deadwood. Using relationships between deadwood biomass and growing stock volume, here we indirectly map this ecosystem compartment within the study area in northern Ukraine. Several machine learning techniques were applied: Random Forest (RF) for the land cover and tree species classification task, k-Nearest Neighbours (k-NN) and Gradient Boosting Machines (GBM) for the deadwood imputation purpose. Land cover (81.9%) and tree species classification (78.9%) were performed with a relatively high level of overall accuracy. Outputs of deadwood biomass mapping using k-NN and GBM matched quite well (8.4 ± 2.3 t·ha−1 (17% of the mean) vs. 8.1 ± 1.7 t·ha−1 (16% of the mean), respectively mean ± SD deadwood biomass stock), indicating a strong potential of ensemble boosters to predict forest biomass in a spatially explicit manner. The main challenges met in the study were related to the limitations of available ground-based data, thus showing the need for national statistical inventory implications in Ukraine.
Options for estimating horizontal visibility in hemiboreal forests using sparse airborne laser scanning data and forest inventory data
Authors: Lang Mait , Vennik Kersti , Põldma Andrus , Nilson Tiit 
Published: August 2021

Abstract
Horizontal visibility v in hemiboreal forest transects was measured in the field and then predicted, both from forest inventory (FI) data and from airborne laser scanning (ALS) data. Stand density N and mean diameter at breast height D were used as arguments in an FI predictive model assuming Poisson distribution of trees on a horizontal plane. It was found that a lack of FI data on forest regrowth and understorey trees caused v to be overestimated. Point cloud metrics of sparse ALS data from summer 2017 and spring 2019 were used as predictive variables for v in regression models. The best models were based on three variables: the 10th percentile of the point cloud height distribution, relative density of returns in a horizontal layer ranging 0.7–2.2 m above the ground, and canopy cover. The models had a coefficient of determination of up to 67% and a residual standard error of less than 25 m. In forests in which fertile soil produces rapid height growth of understorey woody vegetation after recent thinning, visibility was found to be substantially overestimated because the understorey was not detected by the lidar measurements.
Harvendusraietel toimunud metsaõigusnormide rikkumise juhtumite hindamine
Authors: Korjus Henn , Mets Mihkel , Kangur Ahto 
Published: August 2021

Abstract
Three cases of violation of forest management regulations in Estonia in 2004, 2005 and 2007 are presented in the study where the required lower limit of basal area after thinnings was not followed. These stands were revisited in 2017 to assess the impacts of such thinnings. The actual thinnings were well justified from the silvicultural and economic viewpoints. All three stands were ecologically in good condition in 2017. Also, all three stands had already reached the required age or dimensions allowing regeneration cutting in 2017. Forest management regulations on thinning did not work well in the studied cases and therefore some changes in the current regulations are necessary in Estonia.
The enigmatic continental crust of North-Central Africa: Saharan Metacraton or Central Sahara Shield?
Authors: Shellnutt J.G. 
Published: August 2021

AbstractThe continental crust of North-Central Africa between the Tuareg and Arabian-Nubian shields and south to the Central African Orogenic Belt is enigmatic due to the few bedrock exposures especially within the central region. The current understanding, based on a review of geochronology and isotope geochemistry, is that the central Sahara region is a large, coherent craton that was ‘highly remobilized’ during the Late Neoproterozoic amalgamation of Gondwana and referred to as the Saharan Metacraton. However, new data from the Guéra, Ouaddaï, and Mayo Kebbi massifs and the Lake Fitri inlier of Chad suggest that it may be a composite terrane of older cratonic blocks or microcontinents with intervening Mesoproterozoic to Neoproterozoic domains and referred to as the ‘Central Sahara Shield’. It is postulated that the older crust and juvenile crust were sutured together along a Pan-Gondwana collisional belt (Central Sahara Belt) that bisects the central Sahara region. The ‘Central Sahara Shield’ hypothesis suggests the Chad Lineament, a narrow arcuate gravity anomaly within central Chad, could be a collisional belt suture zone and that it may explain the existence of the relatively juvenile crust that typifies southern and eastern Chad. The new data improves upon the existing knowledge and challenges the lithotectonic paradigm of the Saharan Metacraton. Further investigations are required to fully characterize the crust of the central Sahara region and to test the contrasting hypotheses.
Geochemical reconnaissance of the Guéra and Ouaddaï Massifs in Chad: evolution of Proterozoic crust in the Central Sahara Shield
Authors: de Wit M.J. , Bowring S. , Buchwaldt R. , Dudas F.Ö. , MacPhee D. , Tagne-Kamga G. , Dunn N. , Salet A.M. , Nambatingar D. 
Published: August 2021

Abstract
In 1964, W.Q. Kennedy suggested that the crust of Saharan Africa is different from the rest of Africa. To date, the geologic evolution of this region remains obscure because the age and composition of crystalline basement are unknown across large sectors of the Sahara. Most of Africa comprises Archaean cratons surrounded by Palaeo- to Mesoproterozoic orogenic belts, which together constitute Africa’s three major shields (the Southern, Central and West African Shields), finally assembled along belts of Pan-African rocks. By contrast, central Saharan Africa (5.3x106 km2), an area just over half the size of Europe, is considered either as a Neoproterozoic region constructed of relatively juvenile crust (0.5 to 1.0 Ga), or as an older (North African) shield that was reactivated and re-stabilized during that time, a period commonly referred to as “Pan African”. Here, using U-Pb zircon age determinations and Nd isotopic data, we show that remote areas in Chad, part of the undated Darfur Plateau stretching across ¾ million km2 of the central Sahara, comprise an extensive Neoproterozoic crystalline basement of pre-tectonic gabbro-tonalite-granodiorite and predominantly post-tectonic alkali feldspar granites and syenites that intruded between ca. 550 to 1050 Ma. This basement is flanked along its western margin by a Neoproterozoic continental calc-alkaline magmatic arc coupled to a cryptic suture zone that can be traced for ~2400 km from Tibesti through western Darfur into Cameroon. We refer to this as the Central Saharan Belt. This, in a Gondwana framework, is part of a greater arc structure, which we here term the Great Central Gondwana Arc (GCGA). Inherited zircons and Nd isotopic ratios indicate the Neoproterozoic magmas in the central Sahara were predominantly derived from Mesoproterozoic continental lithosphere. Regional deformation between 613 to 623 Ma marks the onset of late alkaline granite magmatism that was widespread across a much larger area of North Africa until about 550 Ma. During this magmatism, the region was exhumed and eroded, leaving a regional peneplain on which early Palaeozoic (Lower-Middle Cambrian) siliciclastic sediments were subsequently deposited, as part of a thick and widespread cover that stretched across much of North Africa and the Arabian Peninsula. Detrital zircons in these cover sequences provide evidence that a substantial volume of detritus was derived from the central Sahara region, because these sequences include ‘Kibaran-age’ zircons (ca. 1000 Ma) for which a source terrain has hitherto been lacking. We propose that, in preference to calling the central Sahara a “ghost” or “meta” craton, it should be called the Central Sahara Shield.
Location of hemorrhage with nontraumatic acute subdural hematoma due to ruptured microaneurysm
Authors: Yanagawa Taro , Yamashita Keiichi , Harada Yoichi , Hatayama Toru , Kono Takuji 
Published: August 2021

Background:
Nontraumatic acute subdural hematoma (ASDH) may be caused by rupture of a microaneurysm of a cortical artery. In some cases, microaneurysms may have been caused by earlier trauma. Although it is difficult to detect microaneurysms on contrast-enhanced computed tomography (CT) angiography or digital subtraction angiography, it may be suspected based on the plain CT scan results and the clinical course.

Case Description:
We experienced three cases presumed to be ASDH due to rupture of a microaneurysm. Plain CT scan showed that the midline shift was smaller than the hematoma thickness, and we judged from the clinical course that there was no trauma immediately before the onset. All three patients had decreased consciousness after arrival and underwent craniotomy for hematoma removal. The source of hemorrhage was in the distal part of the cortical artery, and a microaneurysm was found. In one case, histopathological examination was performed, and traumatic pseudoaneurysm was diagnosed. The postoperative course was good in all three cases.

Conclusion:
If nontraumatic ASDH is suspected, the source of hemorrhage may be located more distally to the middle cerebral artery than in traumatic ASDH; hence, extensive craniotomy is required to search for the location of hemorrhage.
Traumatic brain injury caused by Brazil-nut fruit in the Amazon: A case series
Authors: Ideta Mylena Miki Lopes , Oliveira Louise Makarem , de Castro Gustavo Lopes , Santos Marco Antonio Leal , Simões Erik Leonardo Jennings , Gonçalves Daniel Buzaglo , de Amorim Robson Luis Oliveira 
Published: August 2021

Background:
Traumatic brain injury (TBI) represents one of the leading public health problems and a significant cause of neurological damage. Unintentional causes of TBI are the most frequent. However, fruit falling over the head causing TBI is extremely rare. In the Amazon region, accidents with ouriços, a coconut-like shell fruit, seem relatively common. However, to the best our knowledge, it has never been described in a scientific journal before. Therefore, we aim to evaluate a series of TBI caused by this tropical fruit.

Methods:
This study is a retrospective review of 7 TBI cases due to the fall of ouriços admitted to two tertiary hospitals in the Amazon region from January 2017 to December 2018. The collected data included: age, Glasgow Coma Scale, skull fracture, venous sinus injury, hematoma, surgical treatment, and outcome.

Results:
All patients were men, with an average age of 38, ranging from 8 to 77-years-old. Four out of seven had skull fractures. Five patients developed an epidural hematoma, and two of them had an associated subdural hematoma. Dura mater injury was observed in two patients, whereas four patients were operated. There was one related death.

Conclusion:
This case series is the first to describe an unconventional but potentially fatal cause of TBI in the Amazon: the falling of the Brazil-nut fruit. Most patients were diagnosed with mild TBI. Nevertheless, patients may have cranial fractures and epidural hematomas, leading to death when there’s a delay in medical assistance.
Dentate nucleus deep brain stimulation: Technical note of a novel methodology assisted by tractography
Authors: Diniz Juliete Melo , Cury Rubens Gisbert , Iglesio Ricardo Ferrareto , Lepski Guilherme Alves , França Carina Cura , Barbosa Egberto Reis , de Andrade Daniel Ciampi , Teixeira Manoel Jacobsen , Duarte Kleber Paiva 
Published: August 2021

Background:
The cerebellum has emerged as an attractive and promising target for neuromodulation in movement disorders due to its vast connection with important cortical and subcortical areas. Here, we describe a novel technique of deep brain stimulation (DBS) of the dentate nucleus (DN) aided by tractography.

Methods:
Since 2015, patients with movement disorders including dystonia, ataxia, and tremor have been treated with DN DBS. The cerebellar target was initially localized using coordinates measured from the fastigial point. The target was adjusted with direct visualization of the DN in the susceptibility-weighted imaging and T2 sequences of the MRI and finally refined based on the reconstruction of the dentatorubrothalamic tract (DRTT).

Results:
Three patients were treated with this technique. The final target was located in the anterior portion of DN in close proximity to the DRTT, with the tip of the lead on the white matter and the remaining contacts on the DN. Clinical outcomes were variable and overall positive, with no major side effect.

Conclusion:
Targeting the DN based on tractography of the DRTT seems to be feasible and safe. Larger studies will be necessary to support our preliminary findings.
Indolent nonendemic central nervous system histoplasmosis presenting as an isolated intramedullary enhancing spinal cord lesion
Authors: Recker Matthew J. , Housley Steven B. , Lipinski Lindsay J 
Published: August 2021

Background:
Histoplasma capsulatum infection is largely seen in endemic regions; it results in symptomatic disease in <5% of those infected and is most often a self-limiting respiratory disease. Disseminated histoplasmosis is considered rare in the immunocompetent host. Central nervous system (CNS) dissemination can result in meningitis, encephalitis, and focal lesions in the brain and spinal cord, stroke, and hydrocephalus. An intramedullary spinal cord lesion as the only manifestation of CNS histoplasmosis has been rarely described.

Case Description:
We present an atypical case of a 44-year-old man from a nonendemic region, on adalimumab therapy for ulcerative colitis who developed an isolated intramedullary spinal cord lesion in the setting of disseminated histoplasmosis. His course was initially indolent with vague systemic symptoms that led to consideration of several other diagnoses including sarcoidosis and lymphoma. Biopsies of several positron emission tomography positive lymph nodes revealed granulomatous inflammation, but no firm diagnosis was achieved. He was ultimately diagnosed with histoplasmosis after an acute respiratory infection in the setting of anti-tumor necrosis factor therapy. With appropriate antifungal therapy, the spinal cord lesion regressed. The previous systemic biopsies were re-reviewed, and rare fungal elements consistent with H. capsulatum were identified. A presumptive diagnosis of CNS histoplasmosis was made in the absence of direct laboratory confirmation in the setting of rapid and complete resolution on antifungal therapy.

Conclusion:
Disseminated histoplasmosis should be considered in granulomatous disease, even if the patient resides in a nonendemic region. Furthermore, clinicians should be mindful that CNS histoplasmosis may present in an atypical fashion.
Sporadic supratentorial hemangioblastoma with meningeal affection: A case report and literature review
Authors: Sánchez-Ortega Juan Francisco , Claramonte Marta , Martín Mónica , Calatayud-Pérez Juan 
Published: August 2021

Background:Hemangioblastomas are vascular tumors, of benign behavior, that originate in the central nervous system. Supratentorial hemangioblastomas are extremely rare and are generally associated with Von Hippel-Lindau disease (VHL). The involvement of structures by contiguity, such as blood vessels or meninges, is something exceptional. There are few references in the literature of supratentorial hemangioblastomas with meningeal involvement and most of them are described in reports or small case series.Methods:We performed a systematic review of the literature to observe the characteristics of patients with supratentorial hemangioblastomas with meningeal involvement. In addition, we present the case of a 43-year-old male patient with a sporadic supratentorial hemangioblastoma with both, meningeal and vascular involvement that recurred years after treatment.Results:The patients presented supratentorial tumors with meningeal involvement, we had a 1.2:1 ratio male-female distribution. The mean age was 50 years. Most tumors were located in the cerebral hemispheres, the lobe affected most frequently was the frontal lobe. About 67% of the cases were sporadic and only 21% were related to VHL disease. There were three cases of recurrence after surgery.Conclusion:Supratentorial hemangioblastomas are extremely rare lesions. It is rare for supratentorial hemangioblastomas to invade adjacent structures such as blood vessels or meninges, however, when this happens, it is recommended a preoperative vascular imaging study, especially in parasagittal hemangioblastomas where superior longitudinal sinus may be involved. In these cases,en blocsurgical resection is difficult and the probability of recurrence is higher. Although clinical trials and studies with a greater casuistry are necessary to establish guidelines for the management of supratentorial hemangioblastomas, nowadays, contribution of new cases is useful for understanding this pathology.
Prepontine intracerebral cyst with spontaneous resolution
Authors: Bajwa Mohammad Hamza , Hussain Nasr , Bari Muhammad Ehsan 
Published: August 2021

Background:
Intracranial cysts in the prepontine region are rare and can lead to various complications if not managed appropriately. Symptomatic prepontine cysts may require surgical intervention. However, spontaneous resolution of such cysts is rarely reported in literature.

Case Description:
We describe the case of a middle-aged lady who presented with headaches and imbalance, with no focal neurological deficits on examination. Magnetic resonance imaging (MRI) of the brain showed a prepontine cyst compressing the brainstem with craniocaudal extension through the foramen magnum. The patient was given symptomatic treatment and followed closely with repeat MRI scans. These scans showed regression and eventual disappearance of the lesion, with complete resolution of symptoms.

Conclusion:
In light of the few reported cases of spontaneous resolution of prepontine cysts, we highlight the possibility of these lesions to self-resolve.