scholarly journals Assessing pyrite-derived sulfate in the Mississippi River with four years of sulfur and triple-oxygen isotope data

2021 ◽  
Author(s):  
Bryan Killingsworth ◽  
Huiming Bao ◽  
Issaku Kohl
Keyword(s):  
Oxygen Isotope ◽  
Oxygen Isotopes ◽  
Mississippi River ◽  
Temporal Variability ◽  
Pyrite Oxidation ◽  
Sampling Period ◽  
First Year ◽  
Dominant Process ◽  
Severe Flooding

Riverine dissolved sulfate (SO42−) sulfur and oxygen isotope variations reflect their controls such as SO42− reduction and re-oxidation, and source mixing. However, unconstrained temporal variability of riverine SO42− isotope compositions due to short sampling durations may lead to mischaracterization of SO42− sources, particularly for the pyrite-derived sulfate load. We measured the sulfur and triple-oxygen isotopes (δ34S, δ18O, and ∆’17O) of Mississippi River SO42− with biweekly sampling between 2009-2013 to test isotopic variability and constrain sources. Sulfate δ34S and δ18O ranged from −6.3‰ to −0.2‰ and −3.6‰ to +8.8‰, respectively. Our sampling period captured the most severe flooding and drought in the Mississippi River basin since 1927 and 1956, respectively, and a first year of sampling that was unrepresentative of long-term average SO42−. The δ34SSO4 data indicate pyrite-derived SO42− sources are 74 ±10% of the Mississippi River sulfate budget. Furthermore, pyrite oxidation is implicated as the dominant process supplying SO42− to the Mississippi River, whereas the ∆’17OSO4 data shows 18 ±9% of oxygen in this sulfate is sourced from air O2.

Long-term recovery in the soil profile of 15N from Douglas-fir needles decomposing in the forest floor

1995 ◽  
Vol 25 (5) ◽  
pp. 833-837 ◽  
Author(s):  
CM. Preston ◽  
D.J. Mead
Keyword(s):  
Soil Profile ◽  
Forest Floor ◽  
Mineral Soil ◽  
Sampling Period ◽  
Douglas Fir ◽  
First Year ◽  
N Recovery ◽  
Inorganic N ◽  
Almost All

To follow the movement and transformations of litter-fall N in a forest ecosystem, Douglas-fir (Pseudotsugamenziesii (Mirb.) Franco) foliage labelled with 15N was mixed into the forest floor and left to decompose in steel cylinders of 15 cm diameter X 60 cm length. There were four treatments: 15N-labelled foliage only, foliage plus 200 kg N•ha−1 as urea or NH4NO3, and unamended control. The addition of fertilizer N had no significant effects on 15N recovery or distribution in the soil profile. The overall recovery of 15N to 60 cm depth was 53.7%, 24.9%, and 19.9% after 1, 3, and 7.5 years, respectively. After the first year almost all of the recovered 15N was in the L layer. At 3 years, a higher proportion was found in the FH layer, and by 7.5 years, approximately one-third of the 15N was found in mineral soil horizons. There was very little recovery of 15N in inorganic form (1% or less) after 1 year; in subsequent years inorganic N was found at background levels. Recoveries in soil after 1 and 3 years were similar to those reported for 15N added as inorganic fertilizer in the absence of plant uptake. However, very low losses in the next sampling period (3 to 7.5 years) indicated stabilization of 15N in increasingly recalcitrant forms.

CARDIOLOGICAL PROBLEMS IN THE LONG-TERM PERIOD IN CHILDREN AFTER AORTIC COARCTATION SURGERY TREATMENT IN THE FIRST YEAR OF LIFE

2018 ◽  
Vol 97 (3) ◽  
pp. 24-28
Author(s):  
M.R. Tumanyan ◽  
◽  
A.A. Svobodov ◽  
E.G. Levchenko ◽  
A.G. Anderson ◽  
...  
Keyword(s):  
Aortic Coarctation ◽  
First Year ◽  
First Year Of Life

Muenke syndrome: long-term outcome of a syndrome-specific treatment protocol

2019 ◽  
Vol 24 (4) ◽  
pp. 415-422 ◽  
Author(s):  
Bianca K. den Ottelander ◽  
Robbin de Goederen ◽  
Marie-Lise C. van Veelen ◽  
Stephanie D. C. van de Beeten ◽  
Maarten H. Lequin ◽  
...  
Keyword(s):  
Treatment Protocol ◽  
First Year ◽  
Ventricular Size ◽  
Term Outcome ◽  
Long Term Outcome ◽  
Skull Growth ◽  
Muenke Syndrome ◽  
First Year Of Life

OBJECTIVEThe authors evaluated the long-term outcome of their treatment protocol for Muenke syndrome, which includes a single craniofacial procedure.METHODSThis was a prospective observational cohort study of Muenke syndrome patients who underwent surgery for craniosynostosis within the first year of life. Symptoms and determinants of intracranial hypertension were evaluated by longitudinal monitoring of the presence of papilledema (fundoscopy), obstructive sleep apnea (OSA; with polysomnography), cerebellar tonsillar herniation (MRI studies), ventricular size (MRI and CT studies), and skull growth (occipital frontal head circumference [OFC]). Other evaluated factors included hearing, speech, and ophthalmological outcomes.RESULTSThe study included 38 patients; 36 patients underwent fronto-supraorbital advancement. The median age at last follow-up was 13.2 years (range 1.3–24.4 years). Three patients had papilledema, which was related to ophthalmological disorders in 2 patients. Three patients had mild OSA. Three patients had a Chiari I malformation, and tonsillar descent < 5 mm was present in 6 patients. Tonsillar position was unrelated to papilledema, ventricular size, or restricted skull growth. Ten patients had ventriculomegaly, and the OFC growth curve deflected in 3 patients. Twenty-two patients had hearing loss. Refraction anomalies were diagnosed in 14/15 patients measured at ≥ 8 years of age.CONCLUSIONSPatients with Muenke syndrome treated with a single fronto-supraorbital advancement in their first year of life rarely develop signs of intracranial hypertension, in accordance with the very low prevalence of its causative factors (OSA, hydrocephalus, and restricted skull growth). This illustrates that there is no need for a routine second craniofacial procedure. Patient follow-up should focus on visual assessment and speech and hearing outcomes.

Engineering for good: A case of community driven engineering innovation

2018 ◽  
Vol 6 (1) ◽  
Author(s):  
Chinweike Eseonu ◽  
Martin A Cortes
Keyword(s):  
Engineering Students ◽  
Technology Innovation ◽  
Local Communities ◽  
First Year ◽  
Engineering Curriculum ◽  
Engineering Design Process ◽  
The World ◽  
The University ◽  
Social Consideration

There is a culture of disengagement from social consideration in engineering disciplines. This means that first year engineering students, who arrive planning to change the world through engineering, lose this passion as they progress through the engineering curriculum. The community driven technology innovation and investment program described in this paper is an attempt to reverse this trend by fusing community engagement with the normal engineering design process. This approach differs from existing project or trip based approaches – outreach – because the focus is on local communities with which the university team forms a long-term partnership through weekly in-person meetings and community driven problem statements – engagement.

The ontogeny of long-term memory over the first year-and-a-half of life

1998 ◽  
Vol 32 (2) ◽  
pp. 69-89 ◽  
Author(s):  
Kristin Hartshorn ◽  
Carolyn Rovee-Collier ◽  
Peter Gerhardstein ◽  
Ramesh S. Bhatt ◽  
Teresa L. Wondoloski ◽  
...  
Keyword(s):  
Long Term Memory ◽  
First Year ◽  
Term Memory

Long-Term Follow-Up of Early Cochlear Implant Device Activation

2021 ◽  
pp. 1-11
Author(s):  
Stefanie Bruschke ◽  
Uwe Baumann ◽  
Timo Stöver
Keyword(s):  
Speech Recognition ◽  
Side Effects ◽  
Cochlear Implant ◽  
Surgical Techniques ◽  
Control Group ◽  
First Year ◽  
Safe Procedure ◽  
Sound Processor

Background: The cochlear implant (CI) is a standard procedure for the treatment of patients with severe to profound hearing loss. In the past, a standard healing period of 3–6 weeks occurred after CI surgery before the sound processor was initially activated. Advancements of surgical techniques and instruments allow an earlier initial activation of the processor within 14 days after surgery. Objective: Evaluation of the early CI device activation after CI surgery within 14 days, comparison to the first activation after 4–6 weeks, and assessment of the feasibility and safety of the early fitting over a 12 month observation period were the objectives of this study. Method: In a prospective study, 127 patients scheduled for CI surgery were divided into early fitting group (EF, n = 67) and control group (CG, n = 60). Individual questionnaires were used to evaluate medical and technical outcomes of the EF. Medical side effects, speech recognition, and follow-up effort were compared with the CG within the first year after CI surgery. Results: The early fitting was feasible in 97% of the EF patients. In the EF, the processor was activated 25 days earlier than in the CG. No major complications were observed in either group. At the follow-up appointments, side effects such as pain and balance problems occurred with comparable frequency in both groups. At initial fitting, the EF showed a significantly higher incidence of medical minor complications (p < 0.05). When developing speech recognition within the first year of CI use, no difference was observed. Furthermore, the follow-up effort within the first year after CI surgery was comparable in both groups. Conclusions: Early fitting of the sound processor is a feasible and safe procedure with comparable follow-up effort. Although more early minor complications were observed in the EF, there were no long-term wound healing problems caused by the early fitting. Regular inspection of the magnet strength is recommended as part of the CI follow-up since postoperative wound swelling must be expected. The early fitting procedure enabled a clear reduction in the waiting time between CI surgery and initial sound processor activation.

scholarly journals Depression following traumatic brain injury: a comprehensive overview

2020 ◽  
Vol 0 (0) ◽  
Author(s):  
Marc Fakhoury ◽  
Zaynab Shakkour ◽  
Firas Kobeissy ◽  
Nada Lawand
Keyword(s):  
Traumatic Brain Injury ◽  
Brain Injury ◽  
Health Concern ◽  
First Year ◽  
Comprehensive Overview ◽  
Symptoms Of Depression ◽  
Current State ◽  
Post Traumatic ◽  
Brain Changes

Abstract Traumatic brain injury (TBI) represents a major health concern affecting the neuropsychological health; TBI is accompanied by drastic long-term adverse complications that can influence many aspects of the life of affected individuals. A substantial number of studies have shown that mood disorders, particularly depression, are the most frequent complications encountered in individuals with TBI. Post-traumatic depression (P-TD) is present in approximately 30% of individuals with TBI, with the majority of individuals experiencing symptoms of depression during the first year following head injury. To date, the mechanisms of P-TD are far from being fully understood, and effective treatments that completely halt this condition are still lacking. The aim of this review is to outline the current state of knowledge on the prevalence and risk factors of P-TD, to discuss the accompanying brain changes at the anatomical, molecular and functional levels, and to discuss current approaches used for the treatment of P-TD.

scholarly journals Efficacy of implementing intermittent STOP THE BLEED® reviews on long term retention of hemorrhage control skills of first year medical students

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Enkhtsogt Sainbayar ◽  
Nathan Holt ◽  
Amber Jacobson ◽  
Shalini Bhatia ◽  
Christina Weaver
Keyword(s):  
Medical Students ◽  
Intervention Group ◽  
Training Session ◽  
Likert Scale ◽  
Control Group ◽  
First Year ◽  
Hemorrhage Control ◽  
Term Retention ◽  
Long Term Retention

Abstract Context Some medical schools integrate STOP THE BLEED® training into their curricula to teach students how to identify and stop life threatening bleeds; these classes that are taught as single day didactic and hands-on training sessions without posttraining reviews. To improve retention and confidence in hemorrhage control, additional review opportunities are necessary. Objectives To investigate whether intermittent STOP THE BLEED® reviews were effective for long term retention of hemorrhage control skills and improving perceived confidence. Methods First year osteopathic medical students were asked to complete an eight item survey (five Likert scale and three quiz format questions) before (pretraining) and after (posttraining) completing a STOP THE BLEED® training session. After the surveys were collected, students were randomly assigned to one of two study groups. Over a 12 week intervention period, each group watched a 4 min STOP THE BLEED® review video (intervention group) or a “distractor” video (control group) at 4 week intervals. After the 12 weeks, the students were asked to complete an 11 item survey. Results Scores on the posttraining survey were higher than the pretraining survey. The median score on the five Likert scale items was 23 points for the posttraining survey and 14 points for the pretraining survey. Two of the three knowledge based quiz format questions significantly improved from pretraining to posttraining (both p<0.001). On the 11 item postintervention survey, both groups performed similarly on the three quiz questions (all p>0.18), but the intervention group had much higher scores on the Likert scale items than the control group regarding their confidence in their ability to identify and control bleeding (intervention group median = 21.4 points vs. control group median = 16.8 points). Conclusions Intermittent review videos for STOP THE BLEED® training improved medical students’ confidence in their hemorrhage control skills, but the videos did not improve their ability to correctly answer quiz-format questions compared with the control group.

A Long-Term Study of What Best Predicts Graduating From University Versus Leaving Prior to Graduation

2021 ◽  
pp. 152102512098799
Author(s):  
Teena Willoughby ◽  
Victoria W. Dykstra ◽  
Taylor Heffer ◽  
Joelle Braccio ◽  
Hamnah Shahid
Keyword(s):  
Mental Health ◽  
Social Engagement ◽  
Retention Rates ◽  
First Year ◽  
Long Term Study ◽  
Enrollment Status ◽  
Mental Health Difficulties ◽  
University Degree ◽  
The University

Despite the importance of obtaining a university degree, retention rates remain a concern for many universities. This longitudinal study provides a multi-domain examination of first-year student characteristics and behaviors that best predict which students graduate. Graduation status was assessed seven years after students entered university. Participants (N = 1017; 71% female; mean age in Year 1 was 19 years) enrolled in a Canadian mid-sized university completed a survey, provided their enrollment status over the next 6 years (regardless of whether they left university), and consented to have their grades and status provided by the Registrar. Overall, 79% of students graduated by Year 7 (44% in 4 years). The strongest predictor of graduation was first-year grades. Social engagement in the university also predicted graduation. Surprisingly, mental health was not a significant predictor of graduation. Only a minority of students may experience mental health difficulties to such an extent that it affects their ability to succeed at university.

Yields and nitrogen uptake of grain sorghum in various rotations, including lucerne, annual legume and long fallow

1989 ◽  
Vol 40 (2) ◽  
pp. 255 ◽  
Author(s):  
ICR Holford
Keyword(s):  
Nitrogen Uptake ◽  
Grain Sorghum ◽  
Grazing Management ◽  
First Year ◽  
Red Clay ◽  
Beneficial Effects ◽  
South Wales ◽  
Establishment Method ◽  
Soil Evidence

Long-term yields, nitrogen uptake and responsiveness of grain sorghum following three lucerne rotations, an annual legume rotation, long fallowing, and continuous wheat growing were measured on a black earth and red clay in northern New South Wales. The three lucerne rotations compared two methods of lucerne establishment (with or without a cover crop) and two methods of grazing management (short or extended grazing).There were large beneficial effects of lucerne leys on the first grain sorghum crop, whether they were measured as grain yield, nitrogen content of the foliage and grain, or nitrogen uptake. The effect was much smaller in the second year but it increased in the third and fourth years, in direct relation to the rainfall during the sorghum flowering period. The effect was larger on the black earth than on the red clay, reflecting the much higher lucerne yields on the former soil. Evidence indicated that the nitrogen contribution from lucerne after the first year was no greater than the nitrogen accumulated by long fallowing, and this was attributed to very low rainfall and lucerne yields during the four year ley period.The annual legume rotation suffered from drought and insect damage in most years, and following sorghum yields tended to be lower than those achieved by long fallowing.Differences in the effects of establishment method and grazing management on total lucerne yields were reflected in the differences in subsequent grain sorghum yields. Largest differences were on the black earth where extended grazing lowered the total yields of lucerne and subsequent grain sorghum. Sowing lucerne under wheat had little effect on total yields of lucerne or sorghum.

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