Multilevel analysis of women's education in Ethiopia.

BACKGROUND: Women's education is the base for faster economic growth, longer life expectancy, lower population growth, improved quality of life, and a high rate of investment return in developing countries. Historically, girls were denied opportunities for schooling in most of the regions and societies of Ethiopia. So this study targeted a multilevel analysis of women's education in Ethiopia using the 2016 Ethiopian Demographic and Health Survey data. METHODS: Secondary data on women's data sets were obtained from the 2016 Ethiopia Demographic and Health Survey. A population-based cross-sectional study design was used for the survey. The sampling technique used for the survey was the two-stage sampling technique, which is stratified in the first stage and equal probability systematic selection technique in the second stage. The multi-level ordinal logistic regression model was fitted to identify the determinants of women's education in Ethiopia. RESULTS: Among the random sample of 17137 women, the majority, 65.6 percent were rural residents. Somali regional state (75.3 percent) and the capital city Addis Ababa (8.6 percent) had the highest and lowest percentages of women illiteracy respectively than the remaining administrative units of Ethiopia. The minimum values for the fit statistics and the indicative value of the intra-class correlation (68.3%) of the multilevel model showed its appropriateness to the data. Among the predictors in the final multilevel ordinal logistic regression analysis, women's age at first marriage, residence, and family's wealth index were significant predictors of women's education in Ethiopia. Moreover, the estimates from the random effect result revealed that there is more variation in women's education between the enumeration areas than within the enumeration areas. CONCLUSION: A multi-level ordinal logistic regression analysis has determined higher-level differences in women's education that could not be addressed by a single-level approach. So, the application of standard models by ignoring this variation ought to embrace spurious results, then for such hierarchical data, multilevel modeling is recommended.

Application of two level count regression modeling on the determinants of fertility among married women in Ethiopia.

BACKGROUND: Fertility is the element of population dynamics that has a vital contribution toward changing population size and structure over time. The global population showed a major increment from time to time due to fertility. This increment was higher in south Asia and sub-Saharan Africa including Ethiopia. So this study targeted the factors affecting fertility among married women in Ethiopia through the framework of multilevel count regression analysis using the 2016 Ethiopian Demographic and Health Survey data. METHODS: Secondary data set on the birth records were obtained from the 2016 Ethiopia Demographic and Health Survey. The survey was a population-based cross-sectional study with a two-stage stratified cluster sampling design, where stratification was achieved by separating every region into urban and rural areas except the Addis Ababa region because it is entirely urban. A two-level negative binomial regression model was fitted to spot out the determinants of fertility among married women in Ethiopia. RESULTS: Among the random sample of 6141 women in the country, 27,150 births were recorded based on the 2016 Ethiopian Demographic and Health Survey report. The histograms showed that the data has a positively skewed distribution not extremely picked at the beginning. Findings from the study revealed that the contraception method used, residence, educational level of women, women's age at first birth, and proceeding birth interval were the major predictors of fertility among married women in Ethiopia. Moreover, the estimates from the random effect result revealed that there is more fertility variation between the enumeration areas than within the enumeration areas. CONCLUSION: Unobserved enumeration area fertility differences that cannot be addressed by a single-level approach were determined using a two-level negative binomial regression modeling approach. So, the application of standard models by ignoring this variation ought to embrace spurious results, then for such hierarchical data, multilevel modeling is recommended.

High methionine, low folate and low vitamin B6/B12 (HM-LF-LV) diet causes neurodegeneration and subsequent short-term memory loss.

Methionine is an essential amino acid found in rich quantities in average American diet such as meats, fish and eggs. Excessive consumption of such food often exceeds the normal requirement of the methionine in our body; which found to be related to the development of neurodegenerative disorders. However, the mechanistic pathways of methionine's influence on the brain are unclear. The present study is focus on the effects of high methionine, low folate and low vitamin B6/B12 (HM-LF-LV) diet on the dysfunction of neuronal and vascular specific markers in the brain. C57BL6/J male mice (8-10 week old) were fed with HM-LF-LV diet for a 6 week period. Cognitive function of mice was determine by measuring short-term memory using a Novel Object Recognition test (NORT). Neuronal dysfunction were evaluate by measuring the levels of Neuronal nuclear antigen (NeuN), Neuron-specific-enolase (NSE) and Fluoro-jade C(FJC) fluorescence; while cerebrovascular disruption were evaluate by assessing levels of endothelial junction proteins Vascular Endothelial-Cadherin (VE-Cadherin) and Claudin-5 in harvested brain tissue. Cerebrovascular permeability was assess by evaluating microvascular leakage of fluorescently labeled albumin in vivo. Endothelial and Neuronal Nitric Oxide Synthase (eNOS, nNOS) regulation and vascular inflammation (ICAM: intercellular adhesion molecules) were also evaluate in brain tissue. All assessments were conduct at weekly intervals throughout the study duration. NORT showed a significant temporal decrease in short-term memory of mice fed on HM-LF-LV diet for 6 weeks compared to the wild-type control group. Our experimental data showed that neuronal dysfunction (decreased NeuN levels and increased FJC positive neurons in brain) was more prominent in HM-LF-LV diet fed mice compared to normal diet fed control mice. In experimental mice, cerebrovascular disruption was found to be elevated as evident from increased pial venular permeability (microvascular leakage) and decreased in VE-Cadherin expression compared to control. Slight decrease in nNOS and increase in eNOS in experimental mice suggest a trend towards the decrease in potential for neuronal development due to the long-term HM-LF-LV diet fed. Collectively, our results suggest that a diet containing high methionine, low folate and low vitamin B6/B12 results in increased neuronal degeneration and vascular dysfunction, leading to short-term memory loss. Interestingly, significant neuronal damage precedes vascular dysfunction.

Homocysteine as a Pathological Biomarker for Bone Disease.

In the last few decades, perturbation in methyl-group and homocysteine (Hcy) balance have emerged as independent risk factors in a number of pathological conditions including neurodegenerative disease, cardiovascular dysfunction, cancer development, autoimmune disease, and kidney disease. Recent studies report Hcy to be a newly recognized risk factor for osteoporosis. Elevated Hcy levels are known to modulate osteoclastgenesis by causing detrimental effects on bone via oxidative stress induced metalloproteinase-mediated extracellular matrix degradation and decrease in bone blood flow. Evidence from previous studies also suggests that the decreased chondrocytes mediated bone mineralization in chick limb-bud mesenchymal cells and during the gestational period of ossification in rat model. However, Hcy imbalance and its role in bone loss, regression in vascular invasion, and osteoporosis, are not clearly understood. More investigations are required to explore the complex interplay between Hcy imbalance and onset of bone disease progression. This article reviews the current body of knowledge on regulation of Hcy mediated oxidative stress and its role in bone remodeling, vascular blood flow and progression of bone disease. J. Cell. Physiol. 232: 2704-2709, 2017. © 2016 Wiley Periodicals, Inc.

Multilevel analysis of early initiation of breastfeeding in Ethiopia.

Introduction: Breast milk is the ideal food for the infant and is associated with various public health benefits for both the infant and the mother. The recommended time for early initiation of breastfeeding is within one hour after birth. The prevalence of early initiation of breastfeeding was lower than the plan of the Ethiopian Ministry of Health Sector Development program. Thus, the main objective of this study was to identify individual and group-level factors associated with the early initiation of breastfeeding in Ethiopia. Methods: Secondary data on children was obtained from the 2019 Ethiopia mini-demographic and health survey. The survey was a population-based cross-sectional study and was downloaded from the Measure Demographic and Health Survey website (http://www.measuredhs.com). The study included a random sample of 2,125 last-born infants who were born within 24 months before the survey. A multilevel binary logistic regression analysis was employed to identify the factors associated with the early initiation of breastfeeding in Ethiopia. Statistical data was analyzed using the Statistical Analysis System (SAS 9.4). Results: The prevalence of early breastfeeding initiation was 72%. The higher preceding birth interval (AOR = 1.18, 95% CI: 1.1076, 1.5451), the higher gestational age of infants (AOR = 1.38, 95% CI: 1.2796, 1.4782), the higher number of antenatal care visits (AOR = 1.26, 95% CI: 1.2340, 1.2934), delivery at a health facility (AOR = 1.60, 95% CI: 1.4585, 1.7515), vaginal delivery (AOR = 1.11, 95% CI: 1.1019, 1.1123), mothers with primary education (AOR = 1.14, 95% CI: 1.0204, 1.2738), mothers with secondary education (AOR = 1.54, 95% CI: 1.4678, 1.6190), and mothers with higher education (AOR = 2.62, 95% CI: 2.2574, 3.0526) were associated with higher odds of early initiation of breastfeeding. Being a rural dweller (AOR = 0.63, 95% CI: 0.5684, 0.7038) and the age of mothers (AOR = 0.44, 95% CI: 0.3921, 0.4894) were associated with lower odds of early initiation of breastfeeding. Conclusion: Since the prevalence of early initiation of breastfeeding was minimal among rural mothers who delivered their child by caesarean section, this study strongly suggests special supportive care for these mothers.

Is There a Plateau to the Learning Curve for Acoustic Neuroma Resection?-Experience and Outcomes from a Single Interdisciplinary Team Over Thirty Years.

Objective The evolution of acoustic neuroma (AN) care continues to shift focus on balancing optimized tumor resection and control with preservation of neurological function. Prior learning curve analyses of AN resection have demonstrated a plateau between 20 and 100 surgeries. In this study of 860 consecutive AN surgeries, we investigate the presence of an extended learning curve tail for AN resection. Methods A retrospective cohort study of AN resections by a single interdisciplinary team between 1988 and 2018 was performed. Proportional odds models and restricted cubic splines were used to determine the association between the timing of surgery and odds of improved postoperative outcomes. Results The likelihood of improved postoperative House-Brackmann (HB) scores increased in the first 400 procedures, with HB 1 at 36% in 1988 compared with 79% in 2004. While the probability of a better HB score increased over time, there was a temporary decrease in slope of the cubic spline between 2005 and 2009. The last 400 cases continued to see improvement in optimal HB outcomes: adjusted odds of HB 1 score were twofold higher in both 2005 to 2009 (adjusted odds ratio [aOR]: 2.11, 95% confidence interval [CI]: 1.38-3.22, p < 0.001) and 2010 to 2018 (aOR: 2.18, 95% CI: 1.49-3.19, p < 0.001). Conclusion In contrast to prior studies, our study demonstrates the steepest growth for learning, as measured by rates of preservation of facial function outcomes (HB 1), occurs in the first 400 AN resections. Additionally, improvements in patient outcomes continued even 30 years into practice, underlining the importance of lifelong learning.

Hearing preservation outcomes using direct cranial nerve eight and auditory brainstem response neuromonitoring in the resection of vestibular schwannomas.

OBJECTIVE: Advancements in microsurgical technique and technology continue to improve outcomes in patients with skull base tumor. The primary cranial nerve eight monitoring systems used in hearing preservation surgery for vestibular schwannomas (VSs) are direct cranial nerve eight monitoring (DCNEM) and auditory brainstem response (ABR), although current guidelines are unable to definitively recommend one over the other due to limited literature on the topic. Thus, further research is needed to determine the utility of DCNEM and ABR. The authors performed a retrospective cohort study and created an interactive model that compares hearing preservation outcomes based on tumor size in patients receiving ABR+DCNEM and ABR-only monitoring. METHODS: Twenty-eight patients received ABR+DCNEM and 72 patients received ABR-only monitoring during VS hearing preservation surgery at a single tertiary academic medical center between January 2008 and November 2022. Inclusion criteria consisted of adult patients with a preoperative American Academy of Otolaryngology-Head and Neck Surgery (AAO-HNS) hearing classification of A or B. Tumor size was measured as the maximal medial to lateral length, including the internal auditory canal component. RESULTS: Overall hearing preservation (word recognition score [WRS] > 0%) was achieved in 31 patients with ABR-only monitoring (43.1%) and in 18 patients with ABR+DCNEM (64.3%). Serviceable hearing preservation (AAO-HNS class A or B) was attained in 19 patients with ABR-only monitoring (26.4%) and in 11 patients with ABR+DCNEM (39.3%). There was no difference in overall hearing preservation between the two groups (p = 0.13). Change in tumor size was not associated with the odds of serviceable hearing preservation for the ABR-only group (p = 0.89); however, for ABR+DCNEM, there was some indication of an interaction between tumor size and the association of ABR+DCNEM versus ABR-only monitoring, with the odds of serviceable hearing preservation at p = 0.089. Furthermore, with ABR+DCNEM, every 0.5-cm increase in tumor size was associated with a decreased odds of serviceable hearing preservation on multivariable analysis (p = 0.05). For both overall and serviceable hearing preservation, a worse preoperative AAO-HNS classification was associated with a decreased odds of preservation (OR 0.43, 95% CI 0.19-0.97, p = 0.042; OR 0.17, 95% CI 0.053-0.55, p = 0.0031, respectively). CONCLUSIONS: The result of this interactive model study proposes that there may be a higher chance of hearing preservation when using ABR+DCNEM rather than ABR alone for smaller tumors, with that relationship reversing as tumor size increases.

Application of joint modeling on the determinants of TB Status and CD4 cell count among antiretroviral therapy attendants in Gondar teaching referral hospital, Gonder, Ethiopia.

Background: East African regions were highly affected by tuberculosis and the human immunodeficiency virus. The main objective was to identifying the associated factors with tuberculosis and CD4 cell count of patients in Gonder teaching referral hospital, Gonder, Ethiopia. Methods: A retrospective cohort study was conducted on AIDS patients from 1st January 2018 - to 30th January 2020. This study used joint mixed model, and individual profile plot to identify factors and the changeability inside and between patients respectively. Results: The mean with a standard deviation of weight and a serum hemoglobin concentration of patients were 55.48 (10.21) kilograms and 18.25 (33.028) grams per decilitre respectively.This study shows an opportunistic infection, weight, and serum hemoglobin concentration were significantly associated with the log CD4 cell count and tuberculosis status of patients. Conclusion: The patient who has other diseases is 5.04 more likely to be co-infected with HIV and TB diseases. And also, the estimated odds of being co-infected in both diseases were increased by 1.14 and 1.05 times when a unit change in weight and hemoglobin respectively. Moreover, the estimated odd of patients who have no other related disease were 51.13% less likely to be co-infected with both diseases.

Predictors of the Size and Surgical Freedom of the Trans-Cribriform and Trans-Clival Corridors, a Radiographic Analysis.

Introduction The transcribriform and transclival corridors are endoscopic endonasal approaches used to treat pathologies of the skull base. We present a predictive model that uses the clival length and ethmoidal width to predict the size and surgical freedom (SF) of these corridors. Methods Adult facial computed tomography scans were reviewed. Exclusion criteria included patients <18 years of age or radiographic evidence of trauma, neoplasm, or congenital deformities of the skull base. The images were analyzed using OsiriX MD (Bernex, Switzerland). Patients' demographics, clival length, ethmoidal width, surface area, and others were collected. Linear regression was used to create prediction models for the size and SF of the transclival and transcribriform corridors. Results A total of 103 patients were included with an average age of 44.9 years and 47% males. Females had a smaller clival surface area (8 vs. 9.2 cm 2 , p = 0.001). For transclival corridor, clival length correlated positively with SF in the sagittal plane (rho = 0.44, p < 0.05) and negatively with SF in the coronal plane (rho = - 0.2, p < 0.05). For transcribriform corridor, ethmoidal width correlated positively with SF in the coronal plane (rho = 0.74, p < 0.05), and negatively with SF in the sagittal plane (rho = - 0.2, p < 0.05). Conclusion A significant variability of the bony anatomy of the anterior and central skull base was found. The use of clival length and ethmoidal width as part of preoperative surgical planning might help to overcome the anatomical variability which could affect the adequacy of surgical corridors.

Assessing Surgical Approaches for Acoustic Neuroma Resection: Do Patients Perceive a Difference in Quality-of-Life Outcomes?

OBJECTIVE: The objective of this study is to further patient-physician discussion regarding postoperative quality of life expectations after surgical acoustic neuroma resection. STUDY DESIGN: This study is retrospective prospective. Qualifying patients were identified and administered Penn Acoustic Neuroma Quality-of-Life (PANQOL) Scale. SETTING: The setting was Loyola University Chicago Health System. PATIENTS: Three hundred twenty-six patients at our center with surgically resected acoustic neuroma between January 1990 and July 2021 completed the PANQOL. INTERVENTIONS: During postresection follow-up visits, patients were administered the PANQOL survey. MAIN OUTCOME MEASURES: The total PANQOL is comprised of questions addressing quality of life in seven domains of hearing, balance, face, energy, pain, health, and anxiety. Univariate and multivariable analyses were performed to test for associations between surgical approach and/or patient characteristics. RESULTS: Patients who were treated with retrosigmoid approach reported slightly higher PANQOL pain scores when compared with translabyrinthine approach. No association was found between responses on hearing PANQOL and surgical approach. No association was found between approach and total PANQOL score. However, on average female patients reported lower total PANQOL compared with male patients. CONCLUSION: The lack of association between patient response on hearing PANQOL and surgical approach illustrates the impact of preoperative patient counseling in appropriately setting patient expectations. The difference in pain PANQOL response may be due to a higher rate of occipital neuralgia due to incision placement and soft tissue retraction in the retrosigmoid patient group. Surgeons may consider alternative surgical incisions and soft tissue dissection to improve patient's quality of life with respect to postoperative pain.

Infectious Complications and Operative Management of Intrathecal Baclofen Pumps in the Pediatric Population: A Systematic Review and Meta-Analysis of 20 Years of Pooled Experience.

BACKGROUND: Intrathecal baclofen (ITB) is a treatment modality used to improve the quality of life of patients with intractable spasticity and dystonia. Although it is an effective solution in patients failing oral interventions, it is associated with potential infectious complications. It is known that pediatric patients with ITB have significantly higher infection rates compared with adult patients. The cause of these higher rates in pediatric patients remains unclear. In the present study, we performed a meta-analysis focusing on the incidence of infection, and clarification of potential risk factors for infection in pediatric patients with ITB. METHODS: This meta-analysis was performed in accordance with the PRISMA guidelines. An electronic database search was performed through PubMed, Web of Science, Embase, and Cochrane Library databases. Eligibility criteria and bias assessment were applied before statistical analysis. RESULTS: The 17 studies identified yielded 2238 pediatric patients treated with implanted ITB pumps between 1994 and 2014. Infection comprised 34% of observed complications, second only to catheter malfunction. Pediatric ITB primary infection ranged between 0% and 44% among included studies (interquartile range, 4.85%-18.85%). A linear mixed-effects regression model showed that subfascial implantation had 12% lower primary infection rates compared with subcutaneous implantations across the literature. The relative risk of infection was 56% lower in pediatric patients with subfascially implanted ITB pumps. CONCLUSIONS: Surgeons and clinicians should use these data to better assess patient risk-benefit when considering ITB pump implantation.

Morphometric Study of the Posterior Fossa: Identification of Practical Parameters for Tailored Selection of Surgical Routes to the Petroclival Region.

Introduction The petroclival region is an integral part of the skull base. It can harbor different pathologies and provides access to the petroclival junction and cerebellopontine angle. We present the results of the morphometric analysis of the posterior fossa and a prediction model to enable skull base surgeons to choose an optimal surgical corridor considering patient's bony anatomy. Methods Ninety patients (14 to assess interobserver reliability) with temporal bone computed tomography were selected. Exclusion criteria included patients <18 years of age, radiographic evidence of trauma, infection, or previous surgery. The images were analyzed using OsiriX MD (Bernex, Switzerland). We recorded clival length, vertical angle, and surface area, and petroclival angle, petrous apex, and translabyrinthine corridors volume. Results The average age was 49.5 years (55%) for males. The mean clival length and surface areas were 44.2 mm (standard deviation [SD] ± 4.1) and 8.1 cm 2 (SD ± 1.3). The mean petrous apex and translabyrinthine corridors volumes were 2.2 cm 3 (SD ± 0.6) and 10.1 cm 3 (SD ± 3.7). The mean petroclival angle at the internal auditory canal (IAC) was 154.9 degrees (SD ± 9). The clival length correlated positively with clival surface area (rho = 0.6, p <0.05), petrous apex volume (rho = 0.3, p < 0.05), and translabyrinthine volume (rho = 0.3, p < 0.05). Conclusion The petroclival region is complex and with high variability of surgical significance. The use of preoperative measurements of the clival length and petroclival angle as part of surgical planning that could help the surgeon to choose an optimal surgical corridor by overcoming the anatomical variability elements.

Survival time to complications of congestive heart failure patients at Felege Hiwot comprehensive specialized referral hospital, Bahir Dar, Ethiopia.

BACKGROUNDS: Congestive heart failure is a serious chronic condition when the heart's muscles become too damaged and a condition in which one or both ventricles cannot pump sufficient blood to meet the metabolic needs of the body. This study aimed to identify factors affecting the complications time of congestive heart failure patients treated from January 2016 to December 2019 at Felege Hiwot comprehensive specialized referral hospital in Bahir Dar, Ethiopia. METHODS: A hospital-based retrospective data collection was collected from the medical charts of 218 randomly selected congestive heart failure patients. The Kaplan-Meier curve and the Cox proportional hazards model were used to compare and identify the factors associated with time to complication in patients with congestive heart failure. RESULTS: The median complication time of congestive heart failure patients was 22 months [95% CI: 21.98-28.01]. About 194 (88.99%) of the patients were complicated. The Kaplan-Meier curve depicts the survival probability of complicated patients decreasing as the complication time increases. The hazard ratios for serum sodium concentration, left ventricular ejection fraction, patients from rural areas, age of patients, serum hemoglobin concentration, and New York heart association classes I, II, and III were given 0.94 [95% CI: 0.90-1.00], 0.74 [95% CI: 0.65-0.85], 0.75 [95% CI: 0.68-0.84], 1.28 [95% CI: 1.12-1.46], 0.89 [95% CI: 0.85-0.94], 0.44 [95% CI: 0.36-0.53], 0.54 [95% CI: 0.47-0.62] and 0.73 [95% CI: 0.65-0.81] respectively, and they are statistically associated with the complication time of congestive heart failure patients. CONCLUSIONS: The median complication time of congestive heart failure patients was 22 months. This study strongly suggests that healthcare awareness should be strengthened earlier about the potential complications for patients with lower serum sodium concentrations below the threshold and aged congestive heart failure patients to reduce the risk of developing complications.

Management of Pre-existing Ventriculoperitoneal Shunt in Posterior Vault Distraction for Lambdoid Craniosynostosis: A Case Report and Technical Note.

Posterior vault distraction osteogenesis (DO) is an emerging treatment option for craniosynostosis. Operative nuances detailing surgical management are being described with increasing use and experience. In this article, we discuss the surgical management of an 8-month-old male with a ventriculoperitoneal shunt (VPS) diagnosed with bilateral lambdoid craniosynostosis and Chiari I malformation. The patient underwent successful bilateral posterior fossa DO without surgical re-implantation of the shunt. Pre- and post-operative imaging confirmed no migration of the VPS. Intracranial volume increased by 20.1% and posterior fossa volume increased by 39.9%. Our experience illustrates that posterior vault DO can be done safely in the setting of a parieto-occipital VPS, in a single operative setting, without the need of additional procedures.

Combining Hypermethylated RASSF1A Detection Using ddPCR with miR-371a-3p Testing: An Improved Panel of Liquid Biopsy Biomarkers for Testicular Germ Cell Tumor Patients.

The classical serum tumor markers used routinely in the management of testicular germ cell tumor (TGCT) patients-alpha fetoprotein (AFP) and human chorionic gonadotropin (HCG)-show important limitations. miR-371a-3p is the most recent promising biomarker for TGCTs, but it is not sufficiently informative for detection of teratoma, which is therapeutically relevant. We aimed to test the feasibility of hypermethylated RASSF1A (RASSF1AM) detected in circulating cell-free DNA as a non-invasive diagnostic marker of testicular germ cell tumors, combined with miR-371a-3p. A total of 109 serum samples of patients and 29 sera of healthy young adult males were included, along with representative cell lines and tumor tissue samples. We describe a novel droplet digital polymerase chain reaction (ddPCR) method for quantitatively assessing RASSF1AM in liquid biopsies. Both miR-371a-3p (sensitivity = 85.7%) and RASSF1AM (sensitivity = 86.7%) outperformed the combination of AFP and HCG (sensitivity = 65.5%) for TGCT diagnosis. RASSF1AM detected 88% of teratomas. In this representative cohort, 14 cases were negative for miR-371a-3p, all of which were detected by RASSF1AM, resulting in a combined sensitivity of 100%. We have described a highly sensitive and specific panel of biomarkers for TGCT patients, to be validated in the context of patient follow-up and detection of minimal residual disease.

Geographic landscape of foreign medical graduates in US neurosurgery training programs from 2007 to 2017.

OBJECTIVE: Although foreign medical graduates (FMGs) have been essential to the US physician workforce, the increasing competitiveness has made it progressively challenging for FMGs to match in US neurosurgery programs. We describe geographic origins and characteristics associated with successful match into US neurosurgery training programs. METHODS: Retrospective review of AANS membership data (2007-2017). Scopus was used to collect bibliometrics. RESULTS: From 2009 neurosurgical residents, 165 (8.2%) were FMGs. Most were male (n = 148; 89.6%) with a median age of 34.0 years. Top six feeder countries (TFC) included India (13.9%; n = 23), Lebanon and Pakistan (9.1%; n = 15), Caribbean Region (7.2%; n = 12), Mexico (6.67%; n = 11), and Greece (3.6%; n = 6). Compared to FMGs from non-top feeder countries (NTFC), TFC FMGs had higher H-indices (2 vs 4, p = 0.049), greater number of publications (2 vs 5, p = 0.04), were more likely to have an MBBS/MBBCh (n = 38 vs n = 17, p = 0.03), and had twice as many candidates from major feeder medical schools that successfully matched into a US neurosurgery program (n = 43 vs NTFC = 20, p < 0.001). NTFC FMGs were almost 3-times more likely to match at an affiliated neurosurgery program (8 vs TFC = 3, p = 0.03), while TFC FMGs were 1.5-times more likely to match at an NIH Top-40 program (33 vs NTFC = 21, p = 0.03). CONCLUSIONS: TFC graduates have higher bibliometrics, frequently come from major feeder schools, and have greater match success at a broader selection of programs and NIH top-40 programs. Future studies characterizing FMG country and medical school origins may enable foreign students to geographically target institutions of interest and could allow US programs to better evaluate foreign training environments.

Novel Circulating Hypermethylated RASSF1A ddPCR for Liquid Biopsies in Patients With Pediatric Solid Tumors.

Liquid biopsies can be used to investigate tumor-derived DNA, circulating in the cell-free DNA (cfDNA) pool in blood. We aimed to develop a droplet digital polymerase chain reaction (ddPCR) assay detecting hypermethylation of tumor suppressor gene RASSF1A as a simple standard test to detect various pediatric tumor types in small volume blood samples and to evaluate this test for monitoring treatment response of patients with high-risk neuroblastoma. METHODS: We developed a ddPCR assay to sensitively detect tumor-derived hypermethylated RASSF1A DNA in liquid biopsies. We tested this assay in plasma of 96 patients with neuroblastoma, renal tumors, rhabdomyosarcoma, or Hodgkin lymphoma at diagnosis and in cerebrospinal fluid of four patients with brain tumors. We evaluated the presence of hypermethylated RASSF1A in plasma samples during treatment and follow-up in 47 patients with neuroblastoma treated according to high-risk protocol and correlated results with blood mRNA-based and bone marrow mRNA-based minimal residual disease detection and clinical outcomes. RESULTS: The total cfDNA level was significantly higher in patients with metastatic neuroblastoma and nephroblastoma compared with healthy adult and pediatric controls. Hypermethylated RASSF1A was present in 41 of 42 patients with metastatic neuroblastoma and in all patients with nephroblastoma, with the median percentage of 69% and 21% of total RASSF1A, respectively. Hypermethylated RASSF1A levels decreased during therapy and recurred at relapse. CONCLUSION: Our findings demonstrate the value of ddPCR-based detection of hypermethylated RASSF1A as a circulating molecular tumor marker in neuroblastoma. Our preliminary investigation of RASSF1A hypermethylation detection in circulating cfDNA of other pediatric tumor entities demonstrates potential as a pan-tumor marker, but requires investigation in larger cohorts to evaluate its use and limitations.

Grazing exclosures increase soil organic carbon stock at a rate greater than "4 per 1000" per year across agricultural landscapes in Northern Ethiopia.

The establishment of grazing exclosures is widely practiced to restore degraded agricultural lands and forests. Here, we evaluated the potential of grazing exclosures to contribute to the "4 per 1000" initiative by analyzing the changes in soil organic carbon (SOC) stocks and sequestration (SCS) rates after their establishment on degraded communal grazing lands in Tigray region of Ethiopia. We selected grazing areas that were excluded from grazing for 5 to 24 years across the three agroecological zones of the region and used adjacent open grazing lands (OGLs) as control. Soil samples were collected from two depths (0-15 cm and 15-30 cm) and SOC and aboveground C stocks were quantified in both exclosures and OGLs. The mean SOC stock and SCS rate in exclosures (0-30 cm) were 31 Mg C ha-1 and 3 Mg C ha-1 year-1, which were respectively 166% and 12% higher than that in the OGLs, indicating a positive restoration effect of exclosures on SOC storage. With increasing exclosure age, SOC stock and SCS rate increased in the exclosures but decreased in the OGLs. Higher SOC stock and SCS rate were recorded in 0-15 cm than in 15-30 cm. The relative (i.e., to the SOC stock in OGLs) rates of increase in SOC stocks (70-189‰ year-1) were higher than the 4‰ year-1 and were initially high due to low initial SOC stock but declined over time after a maximum value of SOC stock is reached. Factors such as aboveground biomass, altitude, clay content and precipitation promoted SOC storage in exclosures. Our study highlights the high potential of exclosures for restoring SOC in the 0-30 cm soil depth at a rate greater than the 4‰ value. We argue that practices such as grazing exclosure can be promoted to achieve the climate change mitigation target of the "4‰" initiative.

Structural diversity consistently mediates species richness effects on aboveground carbon along altitudinal gradients in northern Ethiopian grazing exclosures.

Grazing exclosures have been promoted as an effective and low-cost land management strategy to recover vegetation and associated functions in degraded landscapes in the tropics. While grazing exclosures can be important reservoirs of biodiversity and carbon, their potential in playing a dual role of conservation of biodiversity and mitigation of climate change effects is not yet established. To address this gap, we assessed the effect of diversity on aboveground carbon (AGC) and the relative importance of the driving biotic (functional diversity, functional composition and structural diversity) and abiotic (climate, topography and soil) mechanisms. We used a dataset from 133 inventory plots across three altitudinal zones, i.e., highland, midland and lowland, in northern Ethiopia, which allowed local- (within altitudinal zone) and broad- (across altitudinal zones) environmental scale analysis of diversity-AGC relationships. We found that species richness-AGC relationship shifted from neutral in highlands to positive in mid- and lowlands as well as across the altitudinal zones. Structural diversity was consistently the strongest mediator of the positive effects of species richness on AGC within and across altitudinal zones, whereas functional composition linked species richness to AGC at the broad environmental scale only. Abiotic factors had direct and indirect effects via biotic factors on AGC, but their relative importance varied with altitudinal zones. Our results indicate that the effect of species diversity on AGC was altitude-dependent and operated more strongly through structural diversity (representing niche complementarity effect) than functional composition (representing selection effect). Our study suggests that maintaining high structural diversity and managing functionally important species while promoting favourable climatic and soil conditions can enhance carbon storage in grazing exclosures.