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Retrievals of thick cloud optical depth from the Geoscience Laser Altimeter System (GLAS) by calibration of solar background signal
Laser beams emitted from the Geoscience Laser Altimeter System (GLAS), as well as other spaceborne laser instruments, can only penetrate clouds to a limit of a few optical depths. As a result, only optical depths of thinner clouds (< about 3 for GLAS) are retrieved from the reflected lidar signal. This paper presents a comprehensive study of possible retrievals of optical depth of thick clouds using solar background light and treating GLAS as a solar radiometer. To do so one must first calibrate the reflected solar radiation received by the photon-counting detectors of the GLAS 532-nm channel, the primary channel for atmospheric products. Solar background radiation is regarded as a noise to be subtracted in the retrieval process of the lidar products. However, once calibrated, it becomes a signal that can be used in studying the properties of optically thick clouds. In this paper, three calibration methods are presented: (i) calibration with coincident airborne and GLAS observations, (ii) calibration with coincident Geostationary Opera- tional Environmental Satellite (GOES) and GLAS observations of deep convective clouds, and (iii) cali- bration from first principles using optical depth of thin water clouds over ocean retrieved by GLAS active remote sensing. Results from the three methods agree well with each other. Cloud optical depth (COD) is retrieved from the calibrated solar background signal using a one-channel retrieval. Comparison with COD retrieved from GOES during GLAS overpasses shows that the average difference between the two retriev- als is 24%. As an example, the COD values retrieved from GLAS solar background are illustrated for a marine stratocumulus cloud field that is too thick to be penetrated by the GLAS laser. Based on this study, optical depths for thick clouds will be provided as a supplementary product to the existing operational GLAS cloud products in future GLAS data releases
Pre-operative Emotional Health Affects Post-operative Patient Function but not Patient Satisfaction Following Primary Total Hip Arthroplasty
Introduction: Total hip (THA) and knee (TKA) arthroplasty are highly successful treatments for end-stage arthritis. However, a subset of patients experience suboptimal post-operative gain in function. 1, 2 Previous studies have shown that pre-operative emotional health influences outcomes after TKA,3 but there is limited evidence on THA patients. We hypothesized that pre-operative emotional health does not affect patient satisfaction in THA patients.
Methods: A secondary analysis of an existing registry at UMass of primary THA patients between 2008 and 2011 was conducted. Baseline demographic, clinical, emotional health (SF-36 MCS), and physical health (SF-36 PCS) data were collected electronically at the pre-operative visit. Post-operative SF-36 MCS, SF-36 PCS, and satisfaction scores were collected electronically between 6 months through 2 years follow-up. Bivariate analyses and multivariate logistic regression models were used.
Results: The analysis included 316 primary THA patients with mean age 62±11 years, 55% female, mean BMI 30±5, mean PCS 31±8, and mean MCS 51±11. Patients with lower baseline emotional health scores reported significantly reduced mean post-operative physical function and emotional health (p45 (indicating excellent function, national norm = 50); whereas patients with baseline MCS≥50 had a mean 17±11 point increase in post-operative PCS with 71% of these patients reporting PCS\u3e45 (p\u3c0.001).
Conclusion: In THA patients, post-operative emotional health and physical health are positively correlated with baseline emotional health, however post-operative patient satisfaction remains independent of baseline emotional health
Racial Differences in the Effectiveness of Total Knee Arthroplasty (TKA) on Postoperative Pain and Function
Objective: African Americans are less likely than Caucasians to perceive TKA as an effective treatment option. We examined post-TKA pain and function by race, with and without adjusting for demographic and clinical factors on determining racial differences.
Methods: We analyzed data from FORCE-TJR, a national cohort of TJR patients. Patients had primary and unilateral TKA surgeries 07/01/2011-12/31/2014, and completed surveys on demographic and clinical information, including a pre- and 6-month postoperative Knee Injury and Osteoarthritis Outcome Score (KOOS). The KOOS pain and function scores ranged from 0-100 (higher=better). We examined baseline, 6-month, and 6-month change in pain and function by race, and estimated the association between race and outcomes, adjusting for demographic and clinical factors.
Results: Analyses included 5028 white (63% female, 65% income\u3e45k; mean age of 67. BMI of 31) and 270 black patients (80% female, 39% income\u3e45k; mean age of 63, BMI of 34). At baseline, black compared with white patients reported worse knee pain (mean: 39vs.48), and poorer function (mean: 46vs.54). While all patients reported significant gains at 6-month post-surgery, black patients had lower postoperative pain (mean: 71vs.82) and function scores (mean: 73vs.84) than white patients. Although not statistically significant, black patients on average had lower 6-month change than white patients in pain -1.9 (95%CI: -4.4, 0.6) and function -1.6 (95%CI: -3.9, 0.7). Adjusting for covariates, racial differences were significantly more pronounced in change in pain -5.5 (95%CI: -8.3, -2.7) and function -5.6 (95%CI: -8.2, -3.0).
Conclusions: TKAs were as effective in reducing pain and improving functions in blacks as in whites. Adjusting for certain demographic and clinical factors can impact assessment of racial differences and the effectiveness of TKA on postoperative outcomes, as black patients were very different from white patients on these important factors
MYCN Amplification Is Associated with Repressed Cellular Immunity in Neuroblastoma: An In Silico Immunological Analysis of TARGET Database
Purpose: RNA and DNA sequencing data are traditionally used to discern intrinsic cellular pathways in cancer pathogenesis, their utility for investigating the tumor microenvironment (TME) has not been fully explored. This study explores the use of sequencing data to investigate immunity within the TME.
Experimental design: Here, we use immune cell fraction estimation analysis to determine the immune profiles in the microenvironment of neuroblastoma (NB) based on RNA-seq data in the TARGET database. The correlation between immune cell transcripts and prognosis in pediatric NB is also investigated.
Results: In silico analysis revealed a strong inverse correlation between MYCNamplification and leukocyte infiltration. This finding was validated by immunohistochemistry analysis in tumor samples. Moreover, the abundance of CD4 T cells strongly associated with better patient survival regardless of MYCN gene amplification, while those of CD8 T cells, NK or B cells do not. Based on characteristic cytokine expression of CD4 subsets in tumors, the Th2 rather than Th1 levels were associated with better prognosis.
Conclusion: We found that the in silico analysis of TARGET database reflected tumor immunity and was validated by the immunohistochemical tumor data. Our results reveal the association of MYCN amplification with repressed cellular immunity and the potential prognostic value of infiltrating CD4 T cell transcripts in pediatric NB. This analysis illustrates the potential role of MYCN in NB as a regulator of immune privilege and characterizes the power of in silico analysis for delineating cancer immunology and risk stratification
Refractory lympho-epithelial carcinoma of the nasopharynx: a case report illustrating a protracted clinical course
Nasopharyngeal carcinoma is an uncommon cancer in North America. Its clinical course is typified by locally advanced disease at diagnosis and has a high propensity for both regional and distant spread. It is, therefore, typically treated with a combination of radiation and chemotherapy. This report describes our 10-year clinical and radiological findings in a 48-year-old Vietnamese male patient with locally-advanced T4N1M0 lympho-epithelial carcinoma of the nasopharynx. Despite a long remission period after his initial course of aggressive chemoradiation, his tumor recurred locally after 4 years. Thereafter, throughout a period of over 10 years, he has been treated with multiple courses of re-irradiation and three different trials of chemotherapy. He was ultimately provided with over 30 months of progression-free tumor control with the epidermal growth factor receptor (EGFR)-inhibitor cetuximab. This case illustrates the commonly protracted course of this disease and its responsiveness to multiple treatment modalities
Interplay between ferromagnetism, surface states, and quantum corrections in a magnetically doped topological insulator
The breaking of time-reversal symmetry by ferromagnetism is predicted to
yield profound changes to the electronic surface states of a topological
insulator. Here, we report on a concerted set of structural, magnetic,
electrical and spectroscopic measurements of \MBS thin films wherein
photoemission and x-ray magnetic circular dichroism studies have recently shown
surface ferromagnetism in the temperature range 15 K K,
accompanied by a suppressed density of surface states at the Dirac point.
Secondary ion mass spectroscopy and scanning tunneling microscopy reveal an
inhomogeneous distribution of Mn atoms, with a tendency to segregate towards
the sample surface. Magnetometry and anisotropic magnetoresistance measurements
are insensitive to the high temperature ferromagnetism seen in surface studies,
revealing instead a low temperature ferromagnetic phase at K.
The absence of both a magneto-optical Kerr effect and anomalous Hall effect
suggests that this low temperature ferromagnetism is unlikely to be a
homogeneous bulk phase but likely originates in nanoscale near-surface regions
of the bulk where magnetic atoms segregate during sample growth. Although the
samples are not ideal, with both bulk and surface contributions to electron
transport, we measure a magnetoconductance whose behavior is qualitatively
consistent with predictions that the opening of a gap in the Dirac spectrum
drives quantum corrections to the conductance in topological insulators from
the symplectic to the orthogonal class.Comment: To appear in Phys. Rev.
Temperature dependence of erythromelalgia mutation L858F in sodium channel Nav1.7
BACKGROUND: The disabling chronic pain syndrome erythromelalgia (also termed erythermalgia) is characterized by attacks of burning pain in the extremities induced by warmth. Pharmacological treatment is often ineffective, but the pain can be alleviated by cooling of the limbs. Inherited erythromelalgia has recently been linked to mutations in the gene SCN9A, which encodes the voltage-gated sodium channel Nav1.7. Nav1.7 is preferentially expressed in most nociceptive DRG neurons and in sympathetic ganglion neurons. It has recently been shown that several disease-causing erythromelalgia mutations alter channel-gating behavior in a manner that increases DRG neuron excitability. RESULTS: Here we tested the effects of temperature on gating properties of wild type Nav1.7 and mutant L858F channels. Whole-cell voltage-clamp measurements on wild type or L858F channels expressed in HEK293 cells revealed that cooling decreases current density, slows deactivation and increases ramp currents for both mutant and wild type channels. However, cooling differentially shifts the midpoint of steady-state activation in a depolarizing direction for L858F but not for wild type channels. CONCLUSION: The cooling-dependent shift of the activation midpoint of L858F to more positive potentials brings the threshold of activation of the mutant channels closer to that of wild type Nav1.7 at lower temperatures, and is likely to contribute to the alleviation of painful symptoms upon cooling in affected limbs in patients with this erythromelalgia mutation
Hmong Adults Self-Rated Oral Health: A Pilot Study
Since 1975, the Hmong refugee population in the U.S. has increased over 200%. However, little is known about their dental needs or self-rated oral health (SROH). The study aims were to: (1) describe the SROH, self-rated general health (SRGH), and use of dental/physician services; and (2) identify the factors associated with SROH among Hmong adults. A cross-sectional study design with locating sampling methodology was used. Oral health questionnaire was administered to assess SROH and SRGH, past dental and physician visits, and language preference. One hundred twenty adults aged 18–50+ were recruited and 118 had useable information. Of these, 49% rated their oral health as poor/fair and 30% rated their general health as poor/fair. Thirty-nine percent reported that they did not have a regular source of dental care, 46% rated their access to dental care as poor/fair, 43% visited a dentist and 66% visited a physician within the past 12 months. Bivariate analyses demonstrated that access to dental care, past dental visits, age and SRGH were significantly associated with SROH (P \u3c 0.05). Multivariate analyses demonstrated a strong association between access to dental care and good/excellent SROH. About half of Hmong adults rated their oral health and access to dental care as poor. Dental insurance, access to dental care, past preventive dental/physician visits and SRGH were associated with SROH
Privacy in crowdsourcing:a systematic review
The advent of crowdsourcing has brought with it multiple privacy challenges. For example, essential monitoring activities, while necessary and unavoidable, also potentially compromise contributor privacy. We conducted an extensive literature review of the research related to the privacy aspects of crowdsourcing. Our investigation revealed interesting gender differences and also differences in terms of individual perceptions. We conclude by suggesting a number of future research directions.</p
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