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Restoring forest cover is a key action for mitigating climate change. Although monoculture plantations dominate existing commitments to restore forest cover, we lack a synthetic view of how carbon accumulates in these systems. Here, we assemble a global database of 4756 field-plot measurements from monoculture plantations across all forested continents. With these data, we model carbon accumulation in aboveground live tree biomass and examine the biological, environmental, and human drivers that influence this growth. Our results identify four-fold variation in carbon accumulation rates across tree genera, plant functional types, and biomes, as well as the key mediators (e.g., genus of tree, endemism of species, prior land use) of variation in these rates. Our nonlinear growth models advance our understanding of carbon accumulation in forests relative to mean annual rates, particularly during the next few decades that are critical for mitigating climate change.

To constrain global warming, we must strongly curtail greenhouse gas emissions and capture excess atmospheric carbon dioxide.sup.1,2. Regrowing natural forests is a prominent strategy for capturing additional carbon.sup.3, but accurate assessments of its potential are limited by uncertainty and variability in carbon accumulation rates.sup.2,3. To assess why and where rates differ, here we compile 13,112 georeferenced measurements of carbon accumulation. Climatic factors explain variation in rates better than land-use history, so we combine the field measurements with 66 environmental covariate layers to create a global, one-kilometre-resolution map of potential aboveground carbon accumulation rates for the first 30 years of natural forest regrowth. This map shows over 100-fold variation in rates across the globe, and indicates that default rates from the Intergovernmental Panel on Climate Change (IPCC).sup.4,5 may underestimate aboveground carbon accumulation rates by 32 per cent on average and do not capture eight-fold variation within ecozones. Conversely, we conclude that maximum climate mitigation potential from natural forest regrowth is 11 per cent lower than previously reported.sup.3 owing to the use of overly high rates for the location of potential new forest. Although our data compilation includes more studies and sites than previous efforts, our results depend on data availability, which is concentrated in ten countries, and data quality, which varies across studies. However, the plots cover most of the environmental conditions across the areas for which we predicted carbon accumulation rates (except for northern Africa and northeast Asia). We therefore provide a robust and globally consistent tool for assessing natural forest regrowth as a climate mitigation strategy. A one-kilometre-resolution map of aboveground carbon accumulation rates of forest regrowth shows 100-fold variation across the globe, with rates 32% higher on average than IPCC estimates., Author(s): Susan C. Cook-Patton [sup.1] [sup.2] , Sara M. Leavitt [sup.1] , David Gibbs [sup.3] , Nancy L. Harris [sup.3] , Kristine Lister [sup.3] , Kristina J. Anderson-Teixeira [sup.4] [sup.5] [...]

Forests are essential for maintaining the ecological balance of the planet and providing critical ecosystem services. Amidst an increasing rate of global forest loss due to various natural and anthropogenic factors, many countries are committed to battling forest loss by planting new forests. Despite the reported national statistics on the land area in plantations, accurately delineating boundaries of planted forests with remotely sensed data remains a great challenge. In this study, we explored several deep learning approaches based on Convolutional Neural Networks (CNNs) for mapping the extent of planted forests in the Korean Peninsula. Our methodology involved data preprocessing, the application of data augmentation techniques, and rigorous model training, with performance assessed using various evaluation metrics. To ensure robust performance and accuracy, we validated the model's predictions across the Korean Peninsula. Our analysis showed that the integration of the Near Infrared band from 10 m Sentinel-2 remote sensing images with the UNet deep learning model, incorporated with unfrozen ResNet-34 backbone architecture, produced the best model performance. With a recall of 64% and precision of 76.8%, the UNet model surpassed the other pixel-based deep learning models, including DeepLab and Pyramid Sense Parsing, in terms of classification accuracy. When compared to the ensemble-based Random Forest (RF) machine learning model, the RF approach demonstrates a significantly lower recall rate of 55.2% and greater precision of 92%. These findings highlight the unique strength of deep learning and machine learning approaches for mapping planted forests in diverse geographical regions on Earth. [ABSTRACT FROM AUTHOR]

This study explored the impact of a learner-centered, mid-semester course evaluation process called the small group instructional diagnosis (SGID) on student perceptions of dimensions of teaching that promote effective learning. Classes where instructors requested the SGID were randomly assigned to either traditional or learner-centered SGIDs and then students from these classes were surveyed at the end of the semester. Results reveal that the SGID process, independent of format, favorably affects student perception of the overall learning environment. However, the learner-centered SGID had a significantly higher impact on student perceptions of select dimensions of teaching including understanding of course assignments and tests, interactions with classmates, course preparation, motivation to excel, and enthusiasm. Moreover, students in the learner-centered group were significantly more likely to report positive changes in their own behaviors following the SGID.

A 53-year-old woman was admitted to a hospital with tenderness in her right arm, swelling in her right breast, and enlarged lymph nodes. A mammogram and an MRI scan of her right breast showed evidence of an obstruction of her lymph system. She had been bitten by a dog, so her doctors suspected an infectious process. A biopsy of her right breast showed that she had Hodgkin's disease. She was treated with chemotherapy.

An unusual case of Burkitt's lymphoma that developed in a previously healthy woman is discussed. Burkitt's lymphoma usually affects the jaw in adults and the abdomen in children. It most often occurs in immunodeficient patients. A 41-year-old woman developed abnormal sensations in her legs. She later developed jaw pain which subsided but was followed by swelling. An X-ray revealed a 4 centimeter (cm) bone-destroying tumor. The patient developed nausea and double vision before admission to the hospital. On examination, her lymph nodes were swollen and her spleen was enlarged. A cervical-lymph-node biopsy indicated the presence of Burkitt's lymphoma. The patient initially responded to chemotherapy but then suffered a relapse. Salvage therapy was successful. The patient died of a herpesvirus infection after a bone marrow transplant.

Thrombocytopenic purpura may be a symptom of recurring Hodgkin's disease. Thrombocytopenic purpura is the formation of small hemorrhages in the skin or mucous membrane characterized by the presence of a blood antiplatelet factor. Hodgkin's disease is a cancer of the lymph nodes characterized by enlargement of the lymph nodes, spleen and lymphoid tissues. A 37-year-old woman was diagnosed with recurrent Hodgkin's disease involving the stomach and nearby lymph nodes. She was hospitalized for diagnosis of suspected thrombocytopenic purpura and was treated with prednisone and immune globulin therapy. Further evaluation revealed a soft mass adjacent to the stomach and ulceration of the stomach wall. Biopsy specimens taken from the stomach ulcers revealed evidence of lymphoid tissues and recurrent Hodgkin's disease. Her stomach and spleen were surgically removed and she remains in complete remission with the use of maintenance chemotherapy.

A woman, 62, with a congenital heart murmur, was hospitalized for nausea, vomiting and jaundice two weeks after she had undergone restorative valvular surgery. Splenomegaly had been diagnosed in the patient 11 months earlier, which was followed by patient complaints of breathing difficulties and a feeling of heaviness in the stomach. Cardiac ultrasound showed severe heart valve narrowing with mild regurgitation. During the restorative valvular surgery, a large hematoma developed that was removed and the artery repaired. After discharge, the woman experienced fatigue, night sweats, nausea and vomiting. On admission, x-ray examination revealed widespread splenomegaly, with a bend at the intersection of the transverse with the descending colon. Based on a diagnostic procedure, the clinical diagnoses were a delayed reaction to a transfusion, idiopathic splenomegaly, or lymphoma or nontropical splenomegaly. The anatomical diagnoses were a delayed reaction to a transfusion and splenomegaly of unknown etiology.

A 49-year-old man was diagnosed with granulocytic sarcoma. Granulocytic sarcoma is a malignant tumor arising from bone marrow tissue. The patient was admitted to the hospital with myelofibrosis and myeloid metaplasia. Myelofibrosis is replacement of bone marrow tissue with fibrous tissue. Myeloid metaplasia is the occurrence of bone marrow tissue in other parts of the body. He also had painful lesions in his right femur, the thighbone. He started experiencing symptoms after a minor injury to his right knee 11 months before admission to the hospital. An X-ray of his right leg revealed a soft-tissue mass in his femur. A computed tomographic (CT) scan showed an enlarged spleen. Biopsies of the soft-tissue mass and a lymph node found that he had granulocytic sarcoma. His lymph nodes decreased in size and the lesions healed after several courses of chemotherapy.

A 73-year-old man with increasing pain in the upper right side of his face and declining vision in his right eye was diagnosed with small lymphocytic lymphoma of the cavernous sinus. Six years prior to hospital admission, he had been diagnosed with chronic lymphocytic lymphoma (CLL). He also had very limited movement of the right eye, and a computed tomographic (CT) scan revealed a mass in the right eye extending into the cavernous sinus. After 13 days in the hospital, he became blind in his right eye. Cavernous sinus syndrome can have several causes, but his was most likely due to inflammation, a tumor or infection. Given the patient's history of CLL and diabetes, an infection was probable, but no infective agents were discovered. Further testing of tissue samples taken from the mass ruled out an inflammatory cause and confirmed the diagnosis of B-cell small-lymphocytic lymphoma. Upon autopsy, he was found to have leukemic meningitis with lymphoma in the cavernous sinus.

A 54-year-old man with lymphoma and fever of unknown origin was diagnosed with chronic lymphocytic leukemia that evolved into Richter's syndrome, which is a type of Hodgkin's disease. He had previously undergone chemotherapy, with mixed results. After completing therapy, he developed a dry cough, fever, weight loss and anemia. He was admitted to the hospital, and his condition steadily deteriorated. A CT scan revealed a moderately enlarged spleen and liver, and enlarged lymph nodes. Tests for bacteria ruled out infectious diseases such as tuberculosis. Progression of the patient's known B-cell tumor would not have produced the rapid deterioration observed. However, Richter's syndrome tumors are thought to have a B-cell origin, and the disease is characterized by high fever, rapid weight loss, rapidly expanding lymph nodes and enlargement of the spleen and liver. These observations are consistent with the patient's symptoms, and the diagnosis was confirmed at autopsy.

A 49-year-old woman was diagnosed with polyneuropathy, organomegaly, endocrinopathy, M proteins and skin changes (POEMS) syndrome with possible follicular lymphoma. POEMS syndrome is a disorder that affects multiple systems of the body. The patient was admitted to the hospital with vomiting, severe abdominal pain and weight loss. She had been diagnosed with polycythemia vera, or increased levels of red blood cells, six years before admission. Four years before admission, she had been diagnosed with systemic lupus erythematosus, a chronic inflammatory disorder. A computed tomographic (CT) scan of the abdomen revealed abnormal enlargement of the liver, spleen and uterus and accumulation of fluid in the body cavity. A blood test revealed that that she was suffering from POEMS syndrome with possible follicular lymphoma.

A 57-year-old man was diagnosed with systemic mastocytosis. He was admitted to the hospital suffering from low blood pressure and tightness in his chest. He had a 20-year history of headaches, flushing, tear discharge, low blood pressure and occasional fainting. The patient had a series of tests in the hospital, but he was discharged without a diagnosis. A follow-up examination found that the patient had an enlarged spleen, and a bone marrow biopsy indicated that he had indolent systemic mastocytosis. Systemic mastocytosis is a disorder in which mast cells, connective tissue cells involved in allergic reactions, move into the skin, lymph nodes, bone, blood, spleen and liver. Patients with this disease have 15- to 30-minute attacks with flushing, lightheadedness and heart palpitations. Other symptoms during attacks include headaches, chest pain, nausea, diarrhea and breathing difficulties. Seventy percent of patients with indolent systemic mastocytosis survive at least 10 years after diagnosis.

A 52-year-old man was admitted to a hospital with weakness, fatigue and pancytopenia - decreased levels of all blood cell types. He had an abnormal blood smear, increased amounts of immunoglobulins in his blood and protein in his urine. A bone marrow biopsy showed infiltration of the marrow by plasma cells, the blood cells that produce antibodies. He was diagnosed with multiple myeloma and secondary myelofibrosis.