Foundation Treatment of Embankment Dams With Combination of Consolidation and Compaction Groutings

Treatment of soft or weak foundation in a rockfill dam is of importance due to being susceptible to the large settlements, which may cause the dam body subjected to undesirable deformations and even, catastrophic failures. In this paper the stress- strain behavior of an under construction 58 m embankment dam in North-West of Iran, namely Gerdebin dam, and its soft and weak alluvial thick foundation has been assessed numerically. The effect of combination of consolidation and compaction grouting of the basement (as a remediation method) on the dam deformations and stress levels, is investigated. For this purpose, a finite difference based software (FLAC 2D ver. 4.00) has been used to evaluate the effects of the governing mechanical parameters on the dam body behavior. Results show that for certain values of the mechanical properties of the grouted zone, the dam body deformations reaches to the minimum level. The mechanical properties of the grouted zone materials are dependent on the grouting pattern. Hence, an optimized grouting pattern has been achieved for such a case problem. Such an optimized grouting pattern is already under the executing procedure at the dam site

Neurological manifestations as the predictors of severity and mortality in hospitalized individuals with COVID-19: a multicenter prospective clinical study

BACKGROUNDS: The reports of neurological symptoms are increasing in cases with coronavirus disease 2019 (COVID-19). This multi-center prospective study was conducted to determine the incidence of neurological manifestations in hospitalized cases with COVID-19 and assess these symptoms as the predictors of severity and death. METHODS: Hospitalized males and females with COVID-19 who aged over 18 years were included in the study. They were examined by two neurologists at the time of admission. All survived cases were followed for 8 weeks after discharge and 16 weeks if their symptoms had no improvements. RESULTS: We included 873 participants. Of eligible cases, 122 individuals (13.97%) died during hospitalization. The most common non-neurological manifestations were fever (81.1%), cough (76.1%), fatigue (36.1%), and shortness of breath (27.6%). Aging, male gender, co-morbidity, smoking, hemoptysis, chest tightness, and shortness of breath were associated with increased odds of severe cases and/or mortality. There were 561 (64.3%) cases with smell and taste dysfunctions (hyposmia: 58.6%; anosmia: 41.4%; dysguesia: 100%). They were more common among females (69.7%) and non-smokers (66.7%). Hyposmia/anosmia and dysgeusia were found to be associated with reduced odds of severe cases and mortality. Myalgia (24.8%), headaches (12.6%), and dizziness (11.9%) were other common neurological symptoms. Headaches had negative correlation with severity and death due to COVID-19 but myalgia and dizziness were not associated. The cerebrovascular events (n = 10) and status epilepticus (n = 1) were other neurological findings. The partial or full recovery of smell and taste dysfunctions was found in 95.2% after 8 weeks and 97.3% after 16 weeks. The parosmia (30.9%) and phantosmia (9.0%) were also reported during 8 weeks of follow-up. Five cases with mild headaches and 5 cases with myalgia were reported after 16 weeks of discharge. The demyelinating myelitis (n = 1) and Guillain-Barré syndrome (n = 1) were also found during follow-up. CONCLUSION: Neurological symptoms were found to be prevalent among individuals with COVID-19 disease and should not be under-estimated during the current pandemic outbreak

Neuroimaging in anxiety disorders

Neuroimaging studies have gained increasing importance in validating neurobiological network hypotheses for anxiety disorders. Functional imaging procedures and radioligand binding studies in healthy subjects and in patients with anxiety disorders provide growing evidence of the existence of a complex anxiety network, including limbic, brainstem, temporal, and prefrontal cortical regions. Obviously, “normal anxiety” does not equal “pathological anxiety” although many phenomena are evident in healthy subjects, however to a lower extent. Differential effects of distinct brain regions and lateralization phenomena in different anxiety disorders are mentioned. An overview of neuroimaging investigations in anxiety disorders is given after a brief summary of results from healthy volunteers. Concluding implications for future research are made by the authors

New-Onset Panic, Depression with Suicidal Thoughts, and Somatic Symptoms in a Patient with a History of Lyme Disease

Lyme Disease, or Lyme Borreliosis, caused by Borrelia burgdorferi and spread by ticks, is mainly known to cause arthritis and neurological disorders but can also cause psychiatric symptoms such as depression and anxiety. We present a case of a 37-year-old man with no known psychiatric history who developed panic attacks, severe depressive symptoms and suicidal ideation, and neuromuscular complaints including back spasms, joint pain, myalgias, and neuropathic pain. These symptoms began 2 years after being successfully treated for a positive Lyme test after receiving a tick bite. During inpatient psychiatric hospitalization his psychiatric and physical symptoms did not improve with antidepressant and anxiolytic treatments. The patient’s panic attacks resolved after he was discharged and then, months later, treated with long-term antibiotics for suspected “chronic Lyme Disease” (CLD) despite having negative Lyme titers. He however continued to have subsyndromal depressive symptoms and chronic physical symptoms such as fatigue, myalgias, and neuropathy. We discuss the controversy surrounding the diagnosis of CLD and concerns and considerations in the treatment of suspected CLD patients with comorbid psychiatric diagnoses

Study on the stress path dependency of collapse behavior of Gorgan loess implementing unsaturated oedometer devices

Collapsible soils such as loess are particular types of problematic soils, whose collapse potential have caused severe damages to the buildings and structures. Loess is susceptible to large and sudden volume reduction upon wetting in constant normal stress or upon increasing normal stress in constant water content or a combination of these two stress paths. In this research both of these collapse induced paths: wetting and stress paths are investigated on undisturbed specimens of a Loess to observe the effect of various parameters on the collapse behavior of the tested soil., Seven controlled matric suction unsaturated oedometer tests have been conducted on undisturbed specimens taken from loessial soil of Gorgan, a city in Golestan province in Iran to study the collapse mechanisms of this type of soils. Two identical sets of unsaturated oedometer apparatuses designed and developed at Sharif University of Technology, with the capability of controlling matric suction have been utilized. In these tests, the matric suction, vertical net stress, volumetric water content, and vertical deformation of the samples have been controlled and recorded. Tests have been performed under two separate stress paths: constant matric suction with varying vertical net stress (loading and unloading) and constant vertical net stress with varying matric suction (wetting and drying). Obtained results show the high collapse potential of the tested soil and significant effects of stress path, matric suction, and vertical net stress on the collapse behavior of the tested soil