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As major terrestrial carbon sinks, forests play an important role in mitigating climate change. The relationship between the seasonal uptake of carbon and its allocation to woody biomass remains poorly understood, leaving a significant gap in our capacity to predict carbon sequestration by forests. Here, we compare the intra-annual dynamics of carbon fluxes and wood formation across the Northern hemisphere, from carbon assimilation and the formation of non-structural carbon compounds to their incorporation in woody tissues. We show temporally coupled seasonal peaks of carbon assimilation (GPP) and wood cell differentiation, while the two processes are substantially decoupled during off-peak periods. Peaks of cambial activity occur substantially earlier compared to GPP, suggesting the buffer role of non-structural carbohydrates between the processes of carbon assimilation and allocation to wood. Our findings suggest that high-resolution seasonal data of ecosystem carbon fluxes, wood formation and the associated physiological processes may reduce uncertainties in carbon source-sink relationships at different spatial scales, from stand to ecosystem levels.
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Sequestro de Carbono , Carbono , Mudança Climática , Florestas , Estações do Ano , Traqueófitas , Madeira , Carbono/metabolismo , Madeira/metabolismo , Madeira/química , Traqueófitas/metabolismo , Biomassa , Ecossistema , Ciclo do Carbono , Árvores/metabolismoRESUMO
Globally, treelines form a transition zone between tree-dominated forest downslope and treeless alpine vegetation upslope. Treelines represent the highest boundary of "tree" life form in high-elevation mountains and at high latitudes. Recently, treelines have been shifting upslope in response to climate warming, so it has become important to understand global tree diversity and treeline distributions. However, to the best of our knowledge, no global database on tree flora of treelines exists, which limits our capacity to undertake macroecological analyses. Here, for the first time, we present a global data set on the trees of the treeline ecotone, supported by an online ToTE database. We synthesized the database from 1202 studies published over the last 60 years (1962 to 2022) following the Preferred Reporting Items in Systematic Reviews and Meta-Analysis (PRISMA) protocol. We classified the tree species in the database into three categories: treeline tree (TL) species, near to treeline (NTL) tree species, and tree species with an upper montane range limit (TUMR). The ToTE Version-1 presents a total of 208 tree taxa, including 189 species, five subspecies, and 14 varieties, belonging to 54 genera and 26 families distributed across 34 mountain regions worldwide that either grow exactly at the treeline or have a range limit below the treeline. Of the total taxa, 155, 14, and 39 belong to TL, NTL, and TUMR, respectively. Genera such as Abies, Picea, Pinus, Larix, and Juniperus are more represented in the treeline tree category. On the other hand, Acer, Prunus, Populus, and Quercus have more representatives in the near to treeline category, whereas Erica, Nothofagus, and Polylepis contribute more tree species with an upper montane range limit. Furthermore, families such as Rosaceae and Pinaceae include trees that occur both at the treeline and with an upper montane range limit, whereas Sapindaceae includes trees that occur exclusively near to treeline. Our database also includes information on the global distribution patterns of treeline tree species richness across mountains and biomes. The mountains with the highest number of tree species are the Andes (39) followed by the Himalaya (37). Close to 67% of tree species show restricted distributions in different mountains, with the highest endemism in the Andes and the Himalaya. In terms of tree species distribution, Pinus sylvestris was widespread, with a distribution across nine mountain regions, followed by Picea glauca and Fagus sylvatica, both distributed across five mountain regions. In terms of species' distribution across biomes, the temperate biome harbors the highest treeline tree species richness (152 species), which may reflect the fact that the majority of studies are available from the temperate regions of the world. The remaining 56 species are distributed within five other biomes, with the least in dry tropical and subarctic (four species each). Furthermore, currently 40 treeline tree species fall under different International Union for Conservation of Nature threat categories. We anticipate that our database will help advance research on macroecological, biogeographic, evolutionary, climate-change, and conservation aspects of the treeline on a global scale. The data are released under a Creative Commons Attribution 4.0 international license. Please cite this data paper when the data are reused.
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Bases de Dados Factuais , Árvores , Biodiversidade , Florestas , EcossistemaRESUMO
Investigating the microbial communities associated with invasive plant species can provide insights into how these species establish and thrive in new environments. Here, we explored the fungal species associated with the roots of the invasive species Anthemis cotula L. at 12 sites with varying elevations in the Kashmir Himalaya. Illumina MiSeq platform was used to identify the species composition, diversity, and guild structure of these root-associated fungi. The study found a total of 706 fungal operational taxonomic units (OTUs) belonging to 8 phyla, 20 classes, 53 orders, 109 families, and 160 genera associated with roots of A. cotula, with the most common genus being Funneliformis. Arbuscular mycorrhizal fungi (AMF) constituted the largest guild at higher elevations. The study also revealed that out of the 12 OTUs comprising the core mycobiome, 4 OTUs constituted the stable component while the remaining 8 OTUs comprised the dynamic component. While α-diversity did not vary across sites, significant variation was noted in β-diversity. The study confirmed the facilitative role of the microbiome through a greenhouse trial in which a significant effect of soil microbiome on height, shoot biomass, root biomass, number of flower heads, and internal CO2 concentration of the host plant was observed. The study indicates that diverse fungal mutualists get associated with this invasive alien species even in nutrient-rich ruderal habitats and may be contributing to its spread into higher elevations. This study highlights the importance of understanding the role of root-associated fungi in invasion dynamics and the potential use of mycobiome management strategies to control invasive species.(AU)
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Humanos , Micobioma , Anthemis , Microbiota , Raízes de Plantas/microbiologia , Micorrizas/genética , Microbiologia , Técnicas Microbiológicas , Microbiologia do SoloRESUMO
Investigating the microbial communities associated with invasive plant species can provide insights into how these species establish and thrive in new environments. Here, we explored the fungal species associated with the roots of the invasive species Anthemis cotula L. at 12 sites with varying elevations in the Kashmir Himalaya. Illumina MiSeq platform was used to identify the species composition, diversity, and guild structure of these root-associated fungi. The study found a total of 706 fungal operational taxonomic units (OTUs) belonging to 8 phyla, 20 classes, 53 orders, 109 families, and 160 genera associated with roots of A. cotula, with the most common genus being Funneliformis. Arbuscular mycorrhizal fungi (AMF) constituted the largest guild at higher elevations. The study also revealed that out of the 12 OTUs comprising the core mycobiome, 4 OTUs constituted the stable component while the remaining 8 OTUs comprised the dynamic component. While α-diversity did not vary across sites, significant variation was noted in ß-diversity. The study confirmed the facilitative role of the microbiome through a greenhouse trial in which a significant effect of soil microbiome on height, shoot biomass, root biomass, number of flower heads, and internal CO2 concentration of the host plant was observed. The study indicates that diverse fungal mutualists get associated with this invasive alien species even in nutrient-rich ruderal habitats and may be contributing to its spread into higher elevations. This study highlights the importance of understanding the role of root-associated fungi in invasion dynamics and the potential use of mycobiome management strategies to control invasive species.
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Anthemis , Microbiota , Micobioma , Micorrizas , Humanos , Raízes de Plantas/microbiologia , Micorrizas/genética , Microbiologia do Solo , Fungos/genéticaRESUMO
Reliable predictions of future distribution ranges of ecologically important species in response to climate change are required for developing effective management strategies. Here we used an ensemble modelling approach to predict the distribution of three important species of Abies namely, Abies pindrow, Abies spectabilis and Abies densa in the Hindu Kush Himalayan region under the current and two shared socioeconomic pathways (SSP245 and SSP585) and time periods of 2050 and 2090s. A correlative ensemble model using presence/absence data of the three Abies species and 22 environmental variables, including 19 bioclimatic variables and 3 topographic variables, from known distributions was built to predict the potential current and future distribution of these species. The individual models used to build the final ensemble performed well and provided reliable results for both the current and future distribution of all three species. For A. pindrow, precipitation of the driest month (Bio14) was the most important environmental variable with 83.3% contribution to model output while temperature seasonality (Bio4) and annual mean diurnal range (Bio2) were the most important variables for A. spectabilis and A. densa with 48.4% and 46.1% contribution to final model output, respectively. Under current climatic conditions, the ensemble models projected a total suitable habitat of about 433,003 km2, 790,837 km2 and 676,918 km2 for A. pindrow, A. spectabilis and A. densa, respectively, which is approximately 10.36%, 18.91% and 16.91% of the total area of Hindu Kush Himalayan region. Projections of habitat suitability under future climate scenarios for all the shared socioeconomic pathways showed a reduction in potentially suitable habitats with a maximum overall loss of approximately 14% of the total suitable area of A. pindrow under SSP 8.5 by 2090. A decline in total suitable habitat is predicted to be 9.6% in A. spectabilis by 2090 under the SSP585 scenario while in A. densa 6.67% loss in the suitable area is expected by 2050 under the SSP585 scenario. Furthermore, there is no elevational change predicted in the case of A. pindrow while A. spectabilis is expected to show an upward shift by about 29 m per decade and A. densa is showing a downward shift at a rate of 11 m per decade. The results are interesting, and intriguing given the occurrence of these species across the Hindu Kush Himalayan region. Thus, our study underscores the need for consideration of unexpected responses of species to climate change and formulation of strategies for better forest management and conservation of important conifer species, such as A. pindrow, A. spectabilis and A. densa.
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Abies , Mudança Climática , Ecossistema , Monitoramento Ambiental , FlorestasRESUMO
In the present study hexane, benzene, ethyl acetate and ethanol extracts of Pithecellobium dulce root were prepared using soxhlet extractor. The extracts were evaluated for antibacterial activity against one Gram positive (Staphylococcus aureus) and three Gram negative (Acetobacter aceti, Acetobacter aceti, Klebsiella pneumoniae) strains. Disc diffusion method revealed promising antibacterial activity of the extracts prepared in polar solvents (ethyl acetate and ethanol) compared to non-polar solvents (hexane and benzene). Ethanolic root extract was found to be most active against Acetobacter aceti, Staphylococcus aureus, Klebsiella pneumonia and Enterobacter aerogenes bacterial strains. The zone of inhibition of ethanolic root extract against Acetobacter aceti, Staphylococcus aureus, Klebsiella pneumonia and Enterobacter aerogenes bacterial strains was 15.4, 11.0, 19.0 and 13.0â¯mm, respectively at 100â¯mg concentration. Ethyl acetate extract also exhibited good antibacterial activity against Entrobacter aerogenes, Klebsiella pneumonia and Acetobacter aceti. The zone of inhibition of ethyl acetate root extracts against Entrobacter aerogenes, Acetobacter aceti and Klebsiella pneumonia was 10.5, 18.0 and 10.0â¯mm, respectively. The benzene extract showed some activity against Acetobacter aceti with the zone of inhibition 10.0â¯mm. The antibacterial activity of Pithecellobium dulce root hexane extract was found to be negligible against all the four tested strains of bacteria. These findings suggest that ethanolic and ethyl acetate root extracts of Pithecellobium dulce has potential as effective anti-bacterial agent.
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Antibacterianos/farmacologia , Fabaceae/química , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Extratos Vegetais/farmacologia , Raízes de Plantas/química , Antibacterianos/isolamento & purificação , Testes de Sensibilidade a Antimicrobianos por Disco-Difusão , Extratos Vegetais/isolamento & purificaçãoRESUMO
Brain tumors are not rare in children. The common brain tumors in children are medulloblastomas and craniopharyngiomas. Intraparenchymal meningiomas are very rare. We report a case of intraparenchymal meningioma in a child who was operated with a preoperative impression of a primitive neuroectodermal tumor.
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Calcification and ossification are very rare in primary squamous cell carcinoma of the lung. We report a 55-year-old male with primary squamous cell carcinoma of the lung who on histopathological examination was seen to have extensive calcification and ossification. Squamous carcinoma of the lung rarely presents with osteocartilaginous metaplasia. The case is presented here for its unique presentation.
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Calcinose/patologia , Carcinoma de Células Escamosas/patologia , Neoplasias Pulmonares/patologia , Cartilagem/patologia , Humanos , Masculino , Metaplasia , Pessoa de Meia-IdadeRESUMO
AIM: Primary sacral lymphoma is rare. It usually presents in elderly males as low back ache and radiculopathy. CASE REPORT: We hereby report a case of primary sacral lymphoma in a 53-year-old male who presented with low back pain. Imaging showed a sacral lesion which on histopathology proved to be a non-Hodgkin's lymphoma of B cell lineage. MATERIAL AND METHODS: The case is presented for its rarity and for the reason that it mimicked a primary bone tumor. Its recognition is important because it has an excellent prognosis. CONCLUSION: Primary sacral epidural lymphoma should be considered in the differential diagnosis of a sacral mass.
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Linfoma de Células B/patologia , Imageamento por Ressonância Magnética , Sacro/patologia , Neoplasias da Coluna Vertebral/patologia , Biópsia , Diagnóstico Diferencial , Humanos , Dor Lombar/patologia , Dor Lombar/cirurgia , Linfoma de Células B/cirurgia , Masculino , Pessoa de Meia-Idade , Sacro/cirurgia , Neoplasias da Coluna Vertebral/cirurgiaRESUMO
Tuberculosis of breast is a rare disease which is difficult to differentiate from carcinoma of breast. The involvement of breast can be primary or secondary to some focus in body. A case of secondary tuberculosis of right breast in a 21-year-old female from Kashmir, India, is being reported. Presentation was as a painless discharging sinus of right breast. A tubercular foci of rib was the affecting source of disease. No other evidence of tuberculosis was present in the body. Resection of involved rib segment, along with the discharging sinus, was performed. The patient had antitubercular therapy for 9 months, with no recurrence seen in followup.
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Solid pseudopapillary tumor (SPT) of the pancreas is a rare benign or low-grade malignant epithelial tumor that occurs mainly in young females in second to fourth decades of life. Pathologic and imaging findings include a well-defined, encapsulated pancreatic mass with cystic and solid components with evidence of hemorrhage. We report a 23-year-old female who presented with upper abdominal pain of long duration and epigastric mass on palpation. Multidetector-row CT (MDCT) demonstrated a large well-defined heterogeneous attenuation mass, containing hyperdense areas of hemorrhage mixed with solid enhancing and cystic non-enhancing areas, arising from the pancreatic body and tail. Splenic vein thrombosis was present with dilated splenoportal collateral vessels between splenic hilum and portal/superior mesenteric veins, with dilated vessels seen in the gastric wall, with patent portal vein, compatible with sinistral portal hypertension. Typical imaging features and age and sex of the patient suggested a diagnosis of SPT of pancreas complicated by segmental portal hypertension due to splenic vein thrombosis. Histopathology of the biopsy material was confirmatory.
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Hipertensão Portal/diagnóstico , Pâncreas/patologia , Neoplasias Pancreáticas/complicações , Neoplasias Pancreáticas/diagnóstico , Biópsia , Feminino , Histocitoquímica , Humanos , Microscopia , Neoplasias , Neoplasias Pancreáticas/patologia , Radiografia Abdominal , Tomografia Computadorizada por Raios X , Adulto JovemRESUMO
Papillary carcinoma of thyroid is the most common type of thyroid neoplasm which is usually confined to the thyroid and tends to metastasize to regional lymph nodes. Distant metastasis occur in up to 15% of cases. Thymic metastasis from any malignant carcinoma is extremely rare with only four cases reported in medical literature. We report a case of papillary carcinoma of thyroid metastasizing to ectopic cervical thymus which has not been previously reported.
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Carcinoma Papilar/secundário , Neoplasias do Timo/secundário , Neoplasias da Glândula Tireoide/patologia , Adulto , Biópsia por Agulha Fina , Carcinoma Papilar/cirurgia , Feminino , Humanos , Timectomia , Neoplasias do Timo/cirurgia , Neoplasias da Glândula Tireoide/cirurgia , Tireoidectomia , Resultado do TratamentoRESUMO
Primary malignant tumours of spermatic cord are rare. The liposarcoma of spermatic cord is a rare entity and only a few cases have been reported in the literature. We report a case of forty five-year-old male with huge left inguinoscrotal swelling. Fine needle aspiration cytology (FNAC) of swelling revealed the diagnosis of a liposarcoma. The patient was subjected to radical orchidectomy and wide excision. Histopathological examination (HPE) of the resected specimen reported a well-differentiated liposarcoma of the spermatic cord and confirmed the diagnosis.
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Teratomas are tumors composed of tissues derived from more than one germ cell line. Pulmonary teratomas are rare and commonly involve the upper lobe of the left lung. Criteria for pulmonary origin are the exclusion of a gonadal or other extragonadal primary site and origin entirely within the lung. We report a case of a giant pulmonary teratoma in a 2-year-old male child and review the relevant literature.