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Recent advances in miniaturization and commercial availability of critical satellite subsystems and detector technology have made small satellites (SmallSats, including CubeSats) an attractive, low-cost potential solution for space weather research and operational needs. Motivated by the 1st International Workshop on SmallSats for Space Weather Research and Forecasting, held in Washington, DC on 1-4 August 2017, we discuss the need for advanced space weather measurement capabilities, driven by analyses from the World Meteorological Organization (WMO), and how SmallSats can efficiently fill these measurement gaps. We present some current, recent missions and proposed/upcoming mission concepts using SmallSats that enhance space weather research and provide prototyping pathways for future operational applications; how they relate to the WMO requirements; and what challenges remain to be overcome to meet the WMO goals and operational needs in the future. With additional investment from cognizant funding agencies worldwide, SmallSats -- including standalone missions and constellations -- could significantly enhance space weather research and, eventually, operations, by reducing costs and enabling new measurements not feasible from traditional, large, monolithic missions., 24 pages, 5 figures, 2 tables; accepted for publication by Space Weather Journal

We investigate two flow bursts in a series of Earthward bursty bulk flows (BBFs) observed by the Magnetospheric Multiscale spacecraft in Earth's magnetotail at (-24, 7, 4) R-E in Geocentric Solar Magnetospheric coordinates. At the leading edges of the BBFs, we observe complex magnetic field structures. In particular, we focus on one BBF which contains large-amplitude magnetic field fluctuations on the time scale of the proton gyroperiod, and another with a large scale dipolarization. For both events, the magnetic field structures are associated with flux increases of supra-thermal ions with energies greater than or similar to 100 keV. We observe that helium ions dominate the ion flux at energies greater than or similar to 150 keV. We investigate the ion acceleration mechanism and its dependence on the mass and charge state of H+ and He2+ ions. We show that for both events, the ions with gyroradii smaller than the dawn-dusk scale of the structure are accelerated by the ion bulk flow. For ions with larger gyroradii, the acceleration is likely due to a localized spatially limited electric field for the event with a large-scale dipolarization. For the event with fluctuating magnetic field, the acceleration of ions with gyroradii comparable with the scale of the magnetic fluctuations can be explained by resonance acceleration.

In July 2017, the MMS constellation was in the magnetotail with an apogee of 25 Earth radii and an average inter satellite distance of 10 km (i.e. at electron scales). On 23 July around 16:19 UT, MMS was located at the edge of the current sheet which was in a quasi-static state. Then, MMS suddenly entered in the central plasma sheet and detected the local onset of a small substorm as indicated by the AE index (~400 nT). Fast earthward plasma flows were measured for about 1 hour starting with a period of quasi-steady flow and followed by a saw-tooth like series of fast flows associated with dipolarization fronts. This plasma transport sequence finished with a flow reversal still occurring close to the magnetic equator. In the present study, we investigate the energy conversion processes at ion and electron scales for these different phases with particular attention on the processes in the vicinity of the dipolarization fronts.

We report on field‐aligned current observations by the four Magnetospheric Multiscale (MMS) spacecraft near the plasma sheet boundary layer (PSBL) during two major substorms on 23 June 2015. Small‐scale field‐aligned currents were found embedded in fluctuating PSBL flux tubes near the separatrix region. We resolve, for the first time, short‐lived earthward (downward) intense field‐aligned current sheets with thicknesses of a few tens of kilometers, which are well below the ion scale, on flux tubes moving equatorward/earthward during outward plasma sheet expansion. They coincide with upward field‐aligned electron beams with energies of a few hundred eV. These electrons are most likely due to acceleration associated with a reconnection jet or high‐energy ion beam‐produced disturbances. The observations highlight coupling of multiscale processes in PSBL as a consequence of magnetotail reconnection., Key Points Multipoint multiscale observations of field‐aligned currents during storm time substormsSmall‐scale intense field‐aligned currents are found embedded in PSBL flux tubes near separatrix regionField‐aligned low‐energy electron beams correlate with short‐lived localized field‐aligned currents

In 2013, breast cancer affected 232,340 women in the US. Of these diagnoses, 52% were in women aged 65 and older. Although age is a risk factor for the development of breast cancer, women diagnosed at an older age generally have a more favorable prognosis due to often less aggressive tumor biology. Elderly women tend to have higher rates of hormone receptor positive tumors and also tumors with lower proliferative indices (Ki-67). Despite these favorable prognostic factors, breast cancer specific mortality has only decreased at a rate of 1.1% per year for women aged 75+ in comparison to 2.4% per year for women aged

OBJECTIVE Our experience in children with visual pathway glioma (VPG) was reviewed to delineate its clinical characteristics. DESIGN The charts and imaging studies of 21 children with VPG who were followed up in our centre during the last 12 years were reviewed and summarised. RESULTS VPG accounted for 13.1% of all brain tumours treated during this period. Sixty two per cent of the children with VPG had neurofibromatosis type 1 (NF-1). Among these, more than 60% were detected as part of routine work up. In some cases decreasing visual function preceded the appearance of the VPG on imaging studies. Tumour growth rate was markedly unpredictable. All treatment modalities employed led to tumour shrinkage and stabilisation for a variable period, but none was successful in totally eradicating the tumour. Complications were less severe after chemotherapy compared with radiotherapy. Three children died, none with NF-1, with a globular hypothalamic/chiasmatic tumour and accompanying electrolyte abnormalities. CONCLUSIONS NF-1 is a favourable prognostic marker for VPG. Whenever possible a period of observation is necessary before treatment is initiated, during which time tumour size and visual function should be closely followed up; an untoward change in either of these is an indication for the start of treatment, preferably chemotherapy first. The combination of a globular hypothalamic/chiasmatic glioma and electrolyte abnormalities in a child without NF-1 are related to a poor prognosis. Key messages The growth rate of VPG is unpredictable and erratic, especially in children with NF-1 Follow up needs both MRI of brain and visual function studies (funduscopic examination, visual fields and acuity, if possible) Only symptomatic or growing tumours need treatment Although both chemotherapy and radiotherapy should decrease or stabilise tumour growth, chemotherapy, with less side effects, should be used initially Tumour progression is treated with chemotherapy, surgery, or radiotherapy Patients without NF-1 who have globular tumours and electrolyte abnormalities may have a poor prognosis

BACKGROUND: Glutathione S-transferase (GST) enzymes are involved in detoxifying chemotherapy agents and clearing reactive oxygen species formed by radiation. In this study, we explored the relationship between the host GSTP1-105 polymorphism (rs1695), tumor GSTpi protein expression, and clinical outcomes in pediatric medulloblastoma. We hypothesized that the GSTP1-105 G-allele and increased tumor GSTpi expression would be associated with lower progression-free survival and fewer adverse events. METHODS: The study included 106 medulloblastoma/primitive neuroectodermal tumor (PNET) patients seen at Texas Children’s Cancer Center. Genotyping was performed using an Illumina HumanOmni1-Quad BeadChip and tumor GSTpi expression was assessed using immunohistochemistry. We used the Kaplan-Meier method for survival analyses and multivariable logistic regression for toxicity comparisons. RESULTS: Patients with a GSTP1-105 AG/GG genotype or who had received a higher dose of craniospinal radiation (median 36 Gy) had a greater risk of requiring hearing aids than their respective counterparts (OR 4.0, 95%CI 1.2 - 13.6, and OR 3.1, 95%CI 1.1 - 8.8, respectively). Additionally, there was a statistically significant interaction between the two variables. Compared with the lowest risk group (GSTP1-105 AA-lower dose radiation) patients with a GSTP1-105 AG/GG genotype who received a higher dose radiation were 8.4 times more likely to require hearing aids (95%CI 1.4 - 49.9, p-trend ¼ 0.005). When adjusted for age, gender, and amifostine use, the association remained. CONCLUSIONS: The GSTP1-105 G-allele is associated with permanent ototoxicity in pediatric medulloblastoma/PNET and strongly interacts with radiation dose. A possible mechanism for this finding is that the GSTP1-105 G-allele leads to reduced GSTpi free radical detoxification in the setting of multimodality therapy including cisplatin and radiation. Patients with this allele should be considered for clinical trials employing radiation dose modifications and more targeted cytoprotectant strategies than are currently being used with amifostine.

Of thirty-four occurrences of bone pain in seventeen children and young adults who had type-I Gaucher disease, twenty-five were finally diagnosed as bone crises. On the basis of a bone scan with technetium-99m methylene diphosphonate, a correct diagnosis of bone crisis was made for twenty-three occurrences, with a sensitivity of 0.92. At the onset of a crisis, the bone scan typically showed decreased uptake of radionuclide at the involved site. After six weeks, a repeat bone scan of the long bones showed a ring of increased uptake surrounding an area of decreased uptake. At six months, the appearance of the bones on the radionuclide scan was normal.

Purpose: Telomerase is considered a molecular marker for malignancy. The aim of this study was to determine telomerase activity (TA) as a prognostic factor at diagnosis and as a marker for minimal residual disease during therapy and follow-up in nonmetastatic Ewing family of tumors (EFT). Patients and Methods: Primary tumor specimens and 97 peripheral blood (PBL) samples from 31 EFT patients were analyzed for TA by the Telomeric Repeat Amplification Protocol (TRAP assay). The telomerase catalytic subunit (human telomerase reverse transcriptase [hTERT]) gene expression was evaluated by quantitative reverse transcriptase polymerase chain reaction (RT-PCR) and telomere length was determined by Southern blotting. The presence of the EFT chimeric transcripts was analyzed by RT-PCR. Correlations with progression-free survival were evaluated. Results: At diagnosis, TA in primary tumors did not correlate with outcome. During therapy and follow-up, highly significant correlation was observed between high TA in PBL samples and adverse prognosis (P < .0001). None of the patients harboring low TA progressed, with a long follow-up (median, 60 months) and a progression-free survival (PFS) of 100%. In nine patients, high TA actually could predict relapse, long before overt clinical relapse. The group of patients with high TA and positive RT-PCR had the most adverse outcome; PFS of 20% (P = .0025). TA was found to be a better prognostic factor than RT-PCR and histopathologic response at surgery. Conclusion: The results suggest that TA is a significant prognostic variable, superior to the established clinical prognostic parameters during therapy and tumor surveillance. It could be used in combination with RT-PCR for a new risk classification.

BACKGROUND AND PURPOSE: Despite the benign histology of optic pathway glioma (OPG) (low-grade astrocytoma), its biological behavior is unpredictable, and it is unclear whether specific morphologic or anatomic patterns may be predictive of prognosis. It is also unclear whether OPG associated with neurofibromatosis (NF) is a distinct entity from non–NF-OPG. Our purpose was to describe the MR imaging features of OPG, compare the findings between patients with and those without NF, and identify prognostic imaging signs. METHODS: MR examinations of 91 patients with OPG (47 with NF and 44 without) were reviewed at presentation and during follow-up. The images were evaluated for size and extension of tumor, and imaging parameters. Statistical bivariate analysis was used to compare the patients with and those without NF, and Pearson correlation was used to evaluate the correlation between the different imaging parameters and prognosis. Kappa values were calculated to determine intraobserver and interobserver variability. RESULTS: The most common site of involvement in the NF group was the orbital nerve (66%), followed by the chiasm (62%). In the non-NF group, the chiasm was the most common site of involvement (91%); the orbital nerves were involved in only 32%. Extension beyond the optic pathway at diagnosis was uncommon in the NF group (2%) but frequent in the non-NF group (68%). In the NF group, the tumor was smaller and the original shape of the optic pathways was preserved (91% vs. 27% in the non-NF group). The presence of cystic components was significantly more common in the non-NF patients (66% vs. 9% in the NF group). During follow-up, half the NF patients remained stable, in contrast to 5% of the non-NF group. No statistical correlation was found between imaging features and biological behavior of the tumor. CONCLUSION: NF-OPG is a separate entity from non–NF-OPG, with different imaging features and prognosis, thereby warranting a specific diagnostic, clinical, and therapeutic approach.

Growth retardation in childhood was only recently recognized as a prominent feature of Gaucher disease type 1, but there are few data on both the pubertal development and the final outcome of growth and sexual maturation.To investigate the natural pattern of growth and puberty in patients with Gaucher disease type 1 and the effect of splenectomy and enzyme replacement therapy.We retrospectively analyzed growth and puberty in 57 patients with Gaucher disease type 1; 52 were followed since childhood and/or prepuberty and 42 have reached sexual maturity and final height. In the analysis we considered severity of disease, time of splenectomy, and start of enzyme replacement therapy.Deceleration of growth at age 3-5 years was observed in 30 of 57 patients followed since early childhood while untreated: height-SDS decreased from -0.34 +/- 0.42 at age 0-3 years to -1.93 +/- 0.95 (P0.01) at age 7-10 years and was more pronounced with severe disease. A high prevalence (59.6%) of delayed puberty, which was more frequent with severe disease, was observed in 47 patients followed before and throughout puberty. No primary endocrine pathology was found. All patients, untreated as well as treated, with growth and pubertal delay had a spontaneous catch-up, achieved full sexual maturation, and most (83.3%) reached a final height within the range of parental height-standard deviation score. Splenectomy (partial and/or total) performed in 20 patients while still growing had a beneficial effect on growth, which was temporary in some and did not affect puberty. ERT improved growth in 11 patients who started therapy before puberty, as evidenced by a progressive increase in the height-SDS, and seemed to normalize the onset of puberty.Growth retardation in childhood and delay of puberty are characteristic of Gaucher disease type 1 and are more frequent with severe disease. There is a spontaneous catch-up later in life and most patients reach a final height within their genetic growth potential. Enzyme replacement therapy apparently normalizes growth and possibly also the onset of puberty.

To aid clinicians in identifying patients with type I Gaucher disease who are at risk of excessive bleeding, we reviewed the coagulation parameters of six affected patients with bone involvement who underwent orthopaedic surgery at two centers, and of 22 patients under treatment at another, seven of whom had total splenectomy. All patients were of Jewish Ashkenazi origin. Among the latter group, prolonged prothrombin time was noted in 81%. Incidence of clotting factor deficiency were as follows: factor XI, 36.3%; V, 31.8%; VIII, 27.2%; IX, 13.6%; and XII, 27.2%. Most of the abnormalities occurred in the non-splenectomized patients. Two of the six orthopaedic surgery patients had excessive intraoperative and postoperative bleeding. One, who underwent spinal decompression had prolonged prothrombin time, and the other, who had total hip replacement, showed a deficiency of factor XI. The second patient's hemoglobin level was maintained with transfusion of fresh frozen plasma during contralateral hip arthroplasty five months later. We suggest that preoperative evaluation of clotting factors and replacement therapy may prevent excessive bleeding in patients with type I Gaucher disease.

Turcot's syndrome is a rare heritable complex that is characterized by an association between a primary neuroepithelial tumor of the central nervous system and multiple colonic polyps. The aim of this study was to analyze genetic alterations in a case of Turcot's syndrome in a 10.5-year-old boy in whom a colorectal tumor developed 3.5 years following astrocytoma. An APC germline non-sense mutation at codon 1284 leading to a truncated protein was identified, as was a somatic p53 mutation in the colorectal carcinoma in exon 7, codon 244. The latter was not identified in the primary astrocytoma. However, immunohistochemistry revealed high p53 protein expression in both tumors, suggesting an additional p53 mutation in the primary astrocytic tumor. The diverse p53 mutations observed in this unique syndrome in two different sites and stages of the disease may shed light on the multistep progression of the malignant events.

The purpose of this study was to evaluate the prognostic significance of variables in osteosarcoma. We performed a retrospective analysis of 35 patients with non-metastatic limb osteosarcoma that were treated between 1973 and 1994. The following variables were evaluated: age, sex, ethnic group, tumor histology and primary site, alkaline phosphatase (ALP) and lactate dehydrogenase (LDH) levels at diagnosis, treatment regimen, and the histologic response to treatment. Three variables showed significant correlation with prognosis: i) histologic response to preoperative treatment. Disease-free survival (DFS) was 89% in patients with grade III-IV histologic response after a median follow-up (MFU) of 64 months, 67% in patients with grade II after an MFU of 64 months, the patients with grade I response died within 15 months (p0.0001); ii) treatment regimen. DFS was 83% after an MFU of 42 months, 62% after an MFU of 82 months, and 30% after an MFU of 177 months in patients treated by the 90's, 80's, and 70's protocols, respectively (p0.05); iii) corrected ALP (cALP) levels at diagnosis. DFS was 78% after an MFU of 88 months in patients with cALP levels200, and 32% after an MFU of 56 months in patients with cALP levels200 (p=0.01). Low ALP levels, good histologic response to preoperative chemotherapy, and the new therapeutic regimen correlated with good prognosis in patients with osteosarcoma.

We reviewed our experience with diffuse brain stem glioma (dBSG) to evaluate whether any improvement of outcome had occurred in our patients over the years. Of the 24 children referred to our department with suspected dBSG from 1981 to 1997, 5 had a different final diagnosis based on the clinical course. Mean survival in the remainder was 16+/-9.8 months from diagnosis. Survival increased with a longer interval from onset of symptoms to diagnosis (12.9+/-9.0 months with an interval of 1-4 weeks; 19.50+/-10.8 months with a longer interval). Visual symptoms at presentation were associated with a poorer prognosis. Survival was better in the 3- to 5-year age group (at diagnosis). Overall, a trend toward a slight improvement in survival was seen over the years, which we presumptively attribute to the introduction of intensive chemotherapy for these patients. We suggest that chemotherapy may be important in the management of dBSG until a better modality is found.