Search

The magnetotail lobe region at Mercury is characterized by low plasma density and low magnetic field variability compared to the nightside magnetosheath and central plasma sheet. At Mercury, as well as other planets, lobe magnetic fields play a crucial role in storing and releasing magnetic flux in response to changing upstream solar wind conditions such as interplanetary magnetic field (IMF) orientation and solar wind dynamic pressure (Pdyn). This makes the region significant for studying the magnetospheric interaction with the intense solar wind conditions at Mercury's orbit. Here, we identify and analyze magnetotail lobe observations made by the Mercury Surface, Space Environment, Geochemistry and Ranging (MESSENGER) spacecraft during its 4 years orbital phase. We empirically determined a set of criteria using magnetometer (MAG) and the Fast Imaging Plasma Spectrometer instruments onboard MESSENGER to identify lobe magnetic field intervals. From 3,332 MESSENGER orbits, we identify 1,242 lobe field intervals. We derive an expression for the average lobe magnetic field strength in nanotesla with respect to radial distance downtail: Blobe(r) = (135 ± 8) * r(−2.1±0.3) + (31 ± 8). The lobe magnetic field exhibits both small‐scale (∼3 min) and orbit‐to‐orbit (∼8–12 hr) variability in magnetic field strength compared to this averaged field strength expression. The orbit‐to‐orbit variability in lobe field strength is not significantly correlated with estimated IMF orientation, but is directly correlated with Pdyn. Thus, our findings provide evidence for the pressure balance between the inward facing Pdyn on the nightside magnetopause and the outward facing magnetic pressure supplied by the lobes. Plain Language Summary: Of all the planets in the Solar System, Mercury orbits closest to the Sun. As a result, it is subjected to an extreme interplanetary environment driven by solar dynamics. One consequence of the electro‐magnetic interaction of the Sun and Mercury is the formation of the magnetotail, which is the result of magnetic field lines connected to the planet being dragged toward the nightside. A portion of the magnetotail, known as the lobe, is characterized by a relative lack of plasma density compared to the surrounding environment. The strength of the magnetic field in the lobe is directly correlated with the conditions in the interplanetary space surrounding Mercury, making it an important region to study the response of a planetary environment to the extreme conditions at Mercury's orbit. We identify and analyze times in which the Mercury Surface, Space Environment, Geochemistry and Ranging spacecraft observed this important region of Mercury's plasma environment. We find direct evidence for the magnetic field lobe's response to the plasma properties emanating from the Sun. Key Points: 1,242 intervals in which Mercury Surface, Space Environment, Geochemistry and Ranging observed the southern lobe of Mercury were identified in 4 years of orbital dataThe lobe field strength (in nT) falls off with distance downtail according to Blobe(r) = (135 ± 8) * r(−2.1±0.3) + (31 ± 8)Orbit‐to‐orbit variability in lobe field strength is directly attributable to changing upstream solar wind dynamic pressure [ABSTRACT FROM AUTHOR] more...

Background and purpose: Myotonic dystrophy type 1 (DM1) is the most common form of adult-onset muscular dystrophy and is caused by an repeat expansion [r(CUG)exp] located in the 3' untranslated region of the DMPK gene. Symptoms include skeletal and cardiac muscle dysfunction and fibrosis. In DM1, there is a lack of established biomarkers in routine clinical practice. Thus, we aimed to identify a blood biomarker with relevance for DM1-pathophysiology and clinical presentation. Methods: We collected fibroblasts from 11, skeletal muscles from 27, and blood samples from 158 DM1 patients. Moreover, serum, cardiac, and skeletal muscle samples from DMSXL mice were included. We employed proteomics, immunostaining, qPCR and ELISA. Periostin level were correlated with CMRI-data available for some patients. Results: Our studies identified Periostin, a modulator of fibrosis, as a novel biomarker candidate for DM1: proteomic profiling of human fibroblasts and murine skeletal muscles showed significant dysregulation of Periostin. Immunostaining on skeletal and cardiac muscles from DM1 patients and DMSXL mice showed an extracellular increase of Periostin, indicating fibrosis. qPCR studies indicated increased POSTN expression in fibroblasts and muscle. Quantification of Periostin in blood samples from DMSXL mice and two large validation cohorts of DM1 patients showed decreased levels in animals and diseased individuals correlating with repeat expansion and disease severity and presence of cardiac symptoms identified by MRI. Analyses of longitudinal blood samples revealed no correlation with disease progression. Conclusions: Periostin might serve as a novel stratification biomarker for DM1 correlating with disease severity, presence of cardiac malfunction and fibrosis. [ABSTRACT FROM AUTHOR] more...

The Martian crustal magnetic anomalies present a varied, asymmetric obstacle to the imposing draped interplanetary magnetic field (IMF) and solar wind plasma. Magnetic reconnection, a ubiquitous plasma phenomenon responsible for transferring energy and changing magnetic field topology, has been observed throughout the Martian magnetosphere. More specifically, reconnection can occur as a result of the interaction between crustal fields and the IMF, however, the global implications and changes to the overall magnetospheric structure of Mars have yet to be fully understood. Here, we present an analysis to determine these global implications by investigating external conditions that favor reconnection with the underlying crustal anomalies at Mars. To do so, we plot a map of the crustal anomalies' strength and orientation compiled from magnetic field data collected throughout the Mars Atmosphere and Volatile EvolutioN (MAVEN) mission. Then, we create "shear maps" which calculate and plot the angle of shear between the crustal fields and a chosen external field orientation. From there we define a "shear index" to quantify the susceptibility of a region to undergo reconnection based on a given overlaid, external field orientation and the resulting shear map for that region. We demonstrate that the shear analysis technique augments analysis of local reconnection events and suggests southward IMF conditions should favor dayside magnetic reconnection on a more global scale at Mars. Key Points: This study assesses the conditions that favor high‐shear magnetic reconnection between an external magnetic field and the crustal magnetic anomalies at MarsSouthward external fields are most likely to result in magnetic reconnection with the moderate‐to‐strong crustal fields globallyThis suggests large‐scale reconnection‐related phenomena such as the twisted magnetotail are organized by global preference for southward external field conditions [ABSTRACT FROM AUTHOR] more...

Ion precipitation onto Mercury's surface through its magnetospheric cusps acts as a source of planetary atoms to both Mercury's exosphere and magnetosphere. Through the process of ion sputtering, solar wind ions (∼95% protons) impact the surface regolith and liberate material, mostly as neutral atoms. We have identified 2760 northern magnetospheric cusp crossings throughout the MErcury Surface, Space ENvironment, GEochemistry and Ranging (MESSENGER) mission, based on enhancements in proton flux observed by the Fast Imaging Plasma Spectrometer (FIPS). We find cusp crossings spanning 50–85° in magnetic latitude with a geometric center typically at 60–70°. The cusp center is stable about its average but its latitudinal extent varies orbit‐to‐orbit. The mean latitude weakly depends on the magnitude of the interplanetary magnetic field (IMF), dropping by about 1.3° magnetic latitude for each increase of 10 nT in IMF strength. We have used these identified cusp boundaries to estimate the flux of protons which will precipitate onto Mercury's surface. We find an average proton precipitation flux of 1.0 × 107 cm−2 s−1, ranging 3.3 × 104–6.2 × 108 cm−2 s−1, and that this flux can vary substantially between subsequent 10‐s measurements. We also tabulated the peak precipitation fluxes for each cusp crossing. They range 9.8 × 104–1.4 × 109 cm−2 s−1, with a mean of 3.7 × 107 cm−2 s−1. We find strong dependencies on the local time of the cusp crossing as well as on Mercury's orbit around the Sun, which warrant further investigation. Key Points: Mercury's northern cusp was found at 50°–85° magnetic latitude in 2760 MErcury Surface, Space ENvironment, GEochemistry and Ranging orbits, falling by 1.3° per 10 nT increase in interplanetary magnetic fieldAverage proton precipitation flux was 1.0 × 107 cm−2 s−1, ranging 3.3 × 104–6.2 × 108 cm−2 s−1 in the 707 orbits with B vector in viewProton precipitation flux can vary by two orders of magnitude in subsequent 10‐s measurements with peak fluxes up to 1.4 × 109 cm−2 s−1 [ABSTRACT FROM AUTHOR] more...

The Martian magnetotail exhibits a highly twisted configuration, shifting in response to changes in polarity of the interplanetary magnetic field's (IMF) dawn‐dusk (BY) component. Here, we analyze ∼6000 MAVEN orbits to quantify the degree of magnetotail twisting (θTwist) and assess variations as a function of (a) strong planetary crustal field location, (b) Mars season, and (c) downtail distance. The results demonstrate that θTwist is larger for a duskward (+BY) IMF orientation a majority of the time. This preference is likely due to the local orientation of crustal magnetic fields across the surface of Mars, where a +BY IMF orientation presents ideal conditions for magnetic reconnection to occur. Additionally, we observe an increase in θTwist with downtail distance, similar to Earth's magnetotail. These findings suggest that coupling between the IMF and moderate‐to‐weak crustal field regions may play a major role in determining the magnetospheric structure at Mars. Plain Language Summary: MAVEN magnetic field data are analyzed to understand factors that may influence the magnetotail structure at Mars. The Martian magnetotail lobes are observed to be twisted and the degree of this twist can vary. In this work, we calculate the degree of tail twist and monitor how it changes. To understand how the twist changes, we examine these variations as a function of Mars crustal field location, Mars season, and downtail distance away from Mars. Key Points: Mars' magnetotail can be twisted up to 60 deg away from its expected location based on interplanetary magnetic field (IMF) draping, much greater than Earth's tail twistMAVEN observations show that Mars' tail exhibits larger twisting for +BY IMF orientation, compared to −BY IMFMars crustal magnetic fields may play a significant role in shaping the twisted structure of the Martian magnetotail [ABSTRACT FROM AUTHOR] more...

Objective: This study sought to assess whether diabetes affects coronary microvascular function in individuals with normal body weight. Methods: Seventy‐five participants (30 patients with type 2 diabetes [T2D] who were overweight [O‐T2D], 15 patients with T2D who were lean [LnT2D], 15 healthy volunteers who were lean [LnHV], and 15 healthy volunteers who were overweight [O‐HV]) without established cardiovascular disease were recruited. Participants underwent magnetic resonance imaging for assessment of subcutaneous, epicardial, and visceral adipose tissue areas, adenosine stress myocardial blood flow (MBF), and cardiac structure and function. Results: Stress MBF was reduced only in the O‐T2D group (mean [SD], LnHV = 2.07 [0.47] mL/g/min, O‐HV = 2.08 [0.42] mL/g/min, LnT2D = 2.16 [0.36] mL/g/min, O‐T2D = 1.60 [0.28] mL/g/min; p ≤ 0.0001). Accumulation of visceral fat was evident in the LnT2D group at similar levels to the O‐HV group (LnHV = 127 [53] cm2, O‐HV = 181 [60] cm2, LnT2D = 182 [99] cm2, O‐T2D = 288 [72] cm2; p < 0.0001). Only the O‐T2D group showed reductions in left ventricular ejection fraction (LnHV = 63% [4%], O‐HV = 63% [4%], LnT2D = 60% [5%], O‐T2D = 58% [6%]; p = 0.0008) and global longitudinal strain (LnHV = −15.1% [3.1%], O‐HV= −15.2% [3.7%], LnT2D = −13.4% [2.7%], O‐T2D = −11.1% [2.8%]; p = 0.002) compared with both control groups. Conclusions: Patients with T2D and normal body weight do not show alterations in global stress MBF, but they do show significant increases in visceral adiposity. Patients with T2D who were overweight and had no prior cardiovascular disease showed an increase in visceral adiposity and significant reductions in stress MBF. [ABSTRACT FROM AUTHOR] more...

This review paper summarizes the research of Mercury's magnetosphere in the Post-MESSENGER era and compares its dynamics to those in other planetary magnetospheres, especially to those in Earth's magnetosphere. This review starts by introducing the planet Mercury, including its interplanetary environment, magnetosphere, exosphere, and conducting core. The frequent and intense magnetic reconnection on the dayside magnetopause, which is represented by the flux transfer event "shower", is reviewed on how they depend on magnetosheath plasma β and magnetic shear angle across the magnetopause, following by how it contributes to the flux circulation and magnetosphere-surface-exosphere coupling. In the next, Mercury's magnetosphere under extreme solar events, including the core induction and the reconnection erosion on the dayside magnetosphere, the responses of the nightside magnetosphere, are reviewed. Then, the dawn-dusk properties of the plasma sheet, including the features of the ions, the structure of the current sheet, and the dynamics of magnetic reconnection, are summarized. The last topic is devoted to the particle energization in Mercury's magnetosphere, which includes the energization of the Kelvin-Helmholtz waves on the magnetopause boundaries, reconnection-generated magnetic structures, and the cross-tail electric field. In each chapter, the last section discusses the open questions related to each topic, which can be considered by the simulations and the future spacecraft mission. We end this paper by summarizing the future BepiColombo opportunities, which is a joint mission of ESA and JAXA and is en route to Mercury. [ABSTRACT FROM AUTHOR] more...

In this study, we have analyzed Mars Atmosphere and Volatile EvolutioN (MAVEN) observations of fields and plasma signatures associated with an encounter of fully developed Kelvin–Helmholtz (K–H) vortices at the northern polar terminator along Mars' induced magnetosphere boundary. The signatures of the K–H vortices event are: (a) quasi‐periodic, "bipolar‐like" sawtooth magnetic field perturbations, (b) corresponding density decrease, (c) tailward enhancement of plasma velocity for both protons and heavy ions, (d) co‐existence of magnetosheath and planetary plasma in the region prior to the sawtooth magnetic field signature (i.e., mixing region of the vortex structure), and (e) pressure enhancement (minimum) at the edge (center) of the sawtooth magnetic field signature. Our results strongly support the scenario for the non‐linear growth of K–H instability along Mars' induced magnetosphere boundary, where a plasma flow difference between the magnetosheath and induced‐magnetospheric plasma is expected. Our findings are also in good agreement with 3‐dimensional local magnetohydrodynamics simulation results. MAVEN observations of protons with energies greater than 10 keV and results from the Walén analyses suggests the possibility of particle energization within the mixing region of the K–H vortex structure via magnetic reconnection, secondary instabilities or other turbulent processes. We estimate the lower limit on the K–H instability linear growth rate to be ∼5.84 × 10−3 s−1. For these vortices, we estimate the instantaneous atmospheric ion escape flux due to the detachment of plasma clouds during the late non‐linear stage of K–H instability to be ∼5.90 × 1026 particles/s. Extrapolation of loss rates integrated across time and space will require further work. Key Points: Mars Atmosphere and Volatile EvolutioN (MAVEN) observed magnetic field and plasma signatures consistent with the encounter of fully developed Kelvin–Helmholtz (K–H) vortices along Mars' induced magnetospheric boundary (IMB)Close agreement between 3‐D magnetohydrodynamics simulation result and MAVEN observation support the scenario for K–H instability occurrence along Mars' IMBWe estimated the instantaneous atmospheric ion escape flux due to detachment of plasma clouds from K–H instability to be ∼5.9 × 1026 s−1 [ABSTRACT FROM AUTHOR] more...

Filgrastim prophylaxis, both primary and secondary, was rapidly incorporated into clinical practice in the 1990s. When pegfilgrastim became available in 2002, it quickly replaced filgrastim as the colony-stimulating factor (CSF) of choice for prophylaxis. Use of prophylaxis increased markedly in the first decade of this century and has stabilized during the present decade. Data concerning real-world CSF prophylactic practice patterns are limited but suggest that both primary and secondary prophylaxis are common, and that use is frequently inappropriate according to guidelines. The extent of inappropriate use is controversial, as are issues concerning the cost-effectiveness of prophylaxis versus no prophylaxis and the cost-effectiveness of primary prophylaxis versus secondary prophylaxis. Nevertheless, CSF prophylaxis is firmly established as a valuable adjunct to chemotherapy and will almost certainly continue to be widely used for the foreseeable future. In this article, we chronicle the use and impact of CSF prophylaxis in US patients receiving myelosuppressive chemotherapy for non-myeloid malignancies. We emphasize the interplay of expert opinion, clinical evidence, and economic factors in shaping the use of CSFs in clinical practice over time, and, with the recent introduction of new CSF agents and options, we aim to provide useful clinical and economic information for healthcare decision makers. [ABSTRACT FROM AUTHOR] more...

Purpose: Limited information is available regarding elderly patients experiencing febrile neutropenia (FN). This study evaluated FN-related care among elderly cancer patients who received high/intermediate FN-risk chemotherapy and experienced ≥ 1 FN episodes.Methods: We used Medicare data to identify patients aged ≥ 66 years who initiated high/intermediate FN-risk chemotherapy between 1 January 2008 and 31 August 2015 to treat breast cancer (BC), lung cancer (LC), or non-Hodgkin lymphoma (NHL) and had ≥ 1 FN episodes. We identified within-cycle FN episodes for each chemotherapy cycle on Part A inpatient claims or outpatient or Part B claims. We described the FN-related care setting (inpatient hospital, outpatient emergency department [ED], or outpatient non-ED) and reported mean total cost of FN-related care per episode overall and by care setting (adjusted to 2015 US$).Results: We identified 2138, 3521, and 2862 patients with BC, LC, and NHL, respectively, with ≥ 1 FN episodes (total episodes: 2407, 3840, 3587, respectively). Most FN episodes required inpatient care (BC, 88.1%; LC, 93.0%; NHL, 93.2%) with mean hospital length of stay (LOS) 6.2, 6.5, and 6.8 days, respectively. Intensive care unit admission was required for 20.4% of BC, 29.0% of LC, and 25.7% of NHL hospitalizations (mean LOS: 4.7, 4.7, 5.5 days, respectively). The mean total cost of FN care per episode was $11,959 BC, $14,388 LC, and $15,006 NHL, with inpatient admission the costliest care component ($11,826; $14,294; and $14,873; respectively).Conclusions: Among elderly patients with BC, LC, or NHL who experienced FN, most FN episodes required costly hospital care, highlighting the FN burden on healthcare systems. [ABSTRACT FROM AUTHOR] more...

Background: Two recent evaluations reported that many cancer chemotherapy patients discontinue pegfilgrastim prophylaxis (PP) following the first cycle, and that these patients have a higher subsequent risk of febrile neutropenia (FN). Such evidence is based principally on the experience of younger adults with private healthcare coverage, and the generalizability of results to elderly Medicare patients is unknown.Methods: A matched-cohort design and data from the Medicare Claims Research Identifiable Files were employed. The source population comprised cancer patients aged ≥65 years who received chemotherapy with intermediate/high-risk for FN and first-cycle PP. From the source population, beginning with the second cycle, all patients who received PP in all previous cycles were identified. From this sub-set, patients who did not receive PP in the cycle of interest ("comparison patients") were matched to those who received PP in that cycle ("PP patients"); the same process was repeated for subsequent cycles. Odds ratios (OR) for FN (broad and narrow definitions) were estimated using generalized estimating equations.Results: Among 77,616 elderly patients in the source population, 5.3% did not receive second-cycle PP and were matched to those who did. In cycle 2, FN odds were significantly higher among comparison patients vs PP patients when employing the broad definition (OR = 1.9, p < .001) and the narrow definition (OR = 2.1, p < .001). Results for subsequent cycles (broad definition: OR = 2.0, p < .001; narrow definition: OR = 2.1, p < .001) and for the last cycle (broad definition: OR = 1.4, p = .060; narrow definition: OR = 1.7, p = .055) were largely comparable.Conclusions: In this large-scale evaluation of elderly Medicare patients who received myelosuppressive chemotherapy and first-cycle PP in recent US clinical practice, FN risk was substantially lower among patients who continued to receive PP in subsequent cycles vs those who discontinued PP. [ABSTRACT FROM AUTHOR] more...

Objective: Granulocyte colony-stimulating factors (G-CSFs) decrease the incidence of febrile neutropenia (FN) in patients receiving myelosuppressive chemotherapy. This study examines the impact patient travel burden has on administration of prophylactic G-CSFs and the subsequent impact on FN incidence.Methods: Medicare claims data were used to identify a cohort of beneficiaries age 65+ with non-myeloid cancers at high risk for FN between January 2012 and December 2014. Driving distance and time were calculated from patient residence ZIP code to the location of G-CSF and/or chemotherapy administration. Regression models were used to estimate the odds of G-CSF prophylaxis relative to patient driving distance and time, and odds of FN incidence relative to timing of G-CSF administration (optimal [days 2-4 after chemotherapy], sub-optimal [same day], or none).Results: The 52,389 study patients had a mean age of 73.5 years, and were 82% female and 89% white race; 49% had female breast cancer, 12% lung cancer, 15% ovarian cancer, and 24% non-Hodgkin's lymphoma. Of these high FN risk patients, 69% had at least one prophylactic G-CSF administration within at least one chemotherapy cycle. The percentage of patients receiving prophylactic G-CSFs in the first cycle was 56%. Median travel time was slightly longer for patients who did not receive G-CSFs and patients receiving short-acting vs long-acting G-CSFs. The odds of receiving no G-CSFs were 26-52% higher (depending on cancer type) for patients with a >80-min one-way travel time, compared to patients traveling <20-min. Concurrently, the odds of FN (using a "narrow" definition) were 18-93% higher for patients who did not receive G-CSFs in the first cycle of chemotherapy.Conclusions: Travel burden, linked to clinic visits for G-CSF administration following myelosuppressive chemotherapy, is associated with sub-optimal use of G-CSF prophylaxis, which may result in a higher incidence of FN. [ABSTRACT FROM AUTHOR] more...

Background: Two recent evaluations reported that risk of febrile neutropenia (FN) may be higher when pegfilgrastim prophylaxis (PP) is administered on same day as chemotherapy rather than per recommendation (1-3 days following chemotherapy). Such evidence is based largely on the experience of younger privately insured adults and may not be generalizable to older patients in US clinical practice.Methods: A retrospective cohort design and data from Medicare Claims Research Identifiable Files (January 2008-September 2015) were employed. Patients were aged ≥65 years, had breast cancer or non-Hodgkin's lymphoma, received chemotherapy with intermediate/high risk for FN, and received PP in ≥1 cycle; cycles with PP were stratified based on administration day (same-day ["Day 0"] vs. 1-3 days following chemotherapy ["Days 1-3"]) and were pooled for analyses. Adjusted odds ratios (ORs) for FN during the cycle were estimated for patients who received PP on Day 0 versus Days 1-3.Results: Study population included 65,003 patients who received PP in 261,184 cycles; in 5% of cycles, patients received PP on Day 0. Incidence proportion for FN in cycle 1 was 11.4% for Day 0 versus 8.4% for Days 1-3; adjusted OR was 1.4 (p < .001). Incidence proportion for FN when considering all cycles was 7.7% for Day 0 and 6.0% for Days 1-3; adjusted OR was 1.3 (p < .001). Adjusted ORs when considering all cycles and only inpatient FN episodes (1.3, p < .001) and the narrow definition for FN (1.5, p < .001) were similar.Conclusions: Among Medicare patients receiving chemotherapy and PP in US clinical practice, PP was administered before the recommended timing in 5% of cycles and FN incidence was significantly higher in these cycles. Along with prior research, study findings support recently updated US practice guidelines indicating that PP should be administered the day after chemotherapy. [ABSTRACT FROM AUTHOR] more...

Objective: Prophylaxis with granulocyte colony-stimulating factors (G-CSFs) is recommended for patients receiving myelosuppressive chemotherapy regimens with a high risk of febrile neutropenia (FN). G-CSFs should be administered starting the day after chemotherapy, necessitating return trips to the oncology clinic at the end of each cycle. We examined the travel burden related to prophylactic G-CSF injections after chemotherapy in the US.Methods: We used 2012-2014 Medicare claims data to identify a national cohort of beneficiaries age 65+ with non-myeloid cancers who received both chemotherapy and prophylactic G-CSFs. Patient travel origin was based on residence ZIP code. Oncologist practice locations and hospital addresses were obtained from the Medicare Physician Compare and Hospital Compare websites and geocoded using the Google Maps Application Programming Interface (API). Driving distance and time to the care site from each patient ZIP code tabulation area (ZCTA) were calculated using Open Street Maps road networks. Geographic and socio-economic characteristics of each ZCTA from the US Census Bureau's American Community Survey were used to stratify and analyze travel estimates.Results: The mean one-way driving distance to the G-CSF provider was 23.8 (SD 30.1) miles and the mean one-way driving time was 33.3 (SD 37.8) minutes. When stratified by population density, the mean one-way travel time varied from 12.1 (SD 10.1) minutes in Very Dense Urban areas to 76.7 (SD 72.1) minutes in Super Rural areas. About 48% of patients had one-way travel times of <20 minutes, but 19% of patients traveled ≥50 minutes one way for G-CSF prophylaxis. Patients in areas with above average concentrations of aged, poor or disabled residents were more likely to experience longer travel.Conclusions: Administration of G-CSF therapy after chemotherapy can present a significant travel burden for cancer patients. Technological improvements in the form and methods of drug delivery for G-CSFs might significantly reduce this travel burden. [ABSTRACT FROM AUTHOR] more...

Resistance training has become a preferred method for developing muscular strength among various populations. A variety of resistance training modes are available, but there are mixed outcomes regarding strength development among barbells, dumbbells, and weight machines. The purpose of this study was to investigate the differences in strength improvements between dumbbell and FreeMotion machine training. Twenty college-age females were randomly assigned into dumbbell or FreeMotion groups, but only 8 in the dumbbell group completed. Both groups followed a nearly identical progressive strength training program on each of their training modes for 8 weeks. Participants were tested on their one-repetition max (1-RM) on a barbell bench press and barbell back squat before and after the intervention program. A repeated measures ANOVA analysis compared 1-RM changes between groups, and effect sizes were calculated. Significant increases in strength improvements (p < .001) were observed for the dumbbell and FreeMotion groups, with moderate effect size for the 1-RM barbell bench press (d = 0.56) and a moderate to large effect size for the 1-RM barbell back squat (d = 0.73). There was no Group × Time interaction for the strength tests (p = .201 for 1-RM barbell bench press and p = .816 for the 1-RM barbell back squat, respectively). Dumbbells and FreeMotion machines were equally effective in improving strength in college-age females. The findings add to the literature on FreeMotion machines and benefit novice resistance trainers, physical educators, and fitness professionals. The study should be replicated with additional populations. [ABSTRACT FROM AUTHOR] more...

Competitive athletes have goals to optimize performance and to maintain healthy body composition. Sports nutrition is a component of training programs often overlooked by student-athletes and their coaches. The purpose of this study was to examine student-athletes’ sports nutrition knowledge across sex, class level, team, and completion of prior nutrition coursework. Participants included 123 mid-major Division I university student-athletes (47 females and 76 males) from baseball, softball, men’s soccer, track and field, and tennis. The student-athletes completed a survey questionnaire to determine adequate sports nutrition knowledge (mean ≥ 75%). The overall mean sports nutrition knowledge score for the student-athletes was 56.9% which was considered inadequate sports nutrition knowledge (mean < 75%). Only 12 student-athletes achieved adequate sports nutrition knowledge score of 75% or higher. There were no differences by sex, class level, team, and completion of prior nutrition coursework. Student-athletes’ inadequate sports nutrition knowledge may place them at nutrition risk, lead to impaired performance, and affect their lean body mass and energy levels. Athletics personnel should not assume student-athletes have adequate sports nutrition knowledge. Athletic departments may make available a board certified Sports Dietitian or Registered Dietitian and offer classroom or online courses facilitating student-athletes to optimize nutrition knowledge and behaviors. [ABSTRACT FROM AUTHOR] more...

Many contemporary spacecraft materials exhibit cathodoluminescence when exposed to electron flux from the space plasma environment. A quantitative physics-based model has been developed to predict the intensity of the total glow as a function of incident electron current density and energy, temperature, and intrinsic material properties. We present a comparative study of the absolute spectral radiance for more than 20 types of dielectric and composite materials based on this model, which spans more than three orders of magnitude. Variations in intensity are contrasted for different electron environments, different sizes of samples and sample sets, different testing and analysis methods, and data acquired at different test facilities. Together, these results allow us to estimate the accuracy and precision to which laboratory studies may be able to determine the response of spacecraft materials in the actual space environment. It also provides guidance as to the distribution of emissions that may be expected for sets of similar flight hardware under similar environmental conditions. [ABSTRACT FROM PUBLISHER] more...

The inter-conversion of hormonally active cortisol and inactive cortisone is catalyzed by 11 β-hydroxysteroid dehydrogenase (11 β-HSD). This conversion controls the level of active glucocorticoid concentration in tissues. As the fallopian tube plays a major role in the process of fertilization, we wanted to investigate whether 11 β-HSD is present in the human fallopian tube to control the glucocorticoid levels as in other tissues. Isthmic, ampullary and fimbrial portions of the fallopian tube are obtained from patients undergoing hysterectomy and salpingo-oopherectomy for symptomatic leomyomata uteri. 11 β-HSD activities were measured in the homogenates of the tube, cortisol as the steroid substrate. The enzyme activity was expressed as nanomolar cortisone formed per minute per gram of tissue (mean ± S.D.). A significant level of 11 β-HSD activity in oxidation direction was found in all three parts of the tube. There is no significant difference in the distribution of the enzyme activity throughout the tube. When tubal 11 β-HSD activity was compared with endometrial histology, the enzyme activity is significantly lower in proliferative endometrium when compared with secretory endometrium ( P = 0.002). The enzyme activity in inactive endometrium is significantly higher than the active endometrium ( P = 0.05). The presence of 11 β-HSD throughout the fallopian tube and its correlation to endometrial histology is indicative of its probable role in controlling the glucocorticoid levels in the tissue, which in turn may influence the fertilization process. [ABSTRACT FROM AUTHOR] more...