•RF denervation of intervertebral facets has a low success rate for pain relief.•PRF treatment of the DRG was theorized being better for treating chronic LBP.•Patients were 3 groups; PRF treatment of ...the DRG, RF facet ablation and control.•PRF treatment of the DRG resulted in a higher incidence and an extended pain relief.
Percutaneous radiofrequency denervation of the medial dorsal branch is often used for treatment of chronic low back pain originating from intervertebral facets, which is sometimes associated with a low success rate and a higher incidence of recurrence of pain. We theorized that implementing pulsed radiofrequency treatment to dorsal root ganglion would increase the probability of successful pain relief.
150 patients diagnosed with CLBP of a confirmed facet origin were included in a prospective randomized controlled trial and were randomly divided into three equal groups, the first was submitted to percutaneous pulsed radiofrequency treatment of the dorsal root ganglia, the second underwent percutaneous radiofrequency denervation of the medial dorsal branch and the third was a control group that did not receive any radiofrequency treatment. Local injection of a mixture of local anesthetic and a steroid was given to the three groups. Cases were followed for a maximum of 3 years.
98 (65.3 %) patients were females. By 3 months' post procedure, improvement in VAS was significantly better than pretreatment levels in all groups (p= 0.026); the pulsed radiofrequency treatment group, however, had significantly better incidence of improvement when compared to the other two groups (p= 0.014).The control group lost improvement by 1-year follow-up (p=0.63). At 2 years' follow-up, the pulsed radiofrequency treatment of the dorsal root ganglia group maintained significant improvement (p= 0.041) whereas the medial branch denervation group lost its significant effect (p=0.32).By the end of follow-up period, only pulsed radiofrequency treatment of the dorsal root ganglia group kept significant improvement (p=0.044).
In CLBP of facet origin, pulsed radiofrequency treatment of the dorsal root ganglia provides both a higher incidence as well as an extended period of pain relief compared to radiofrequency ablation of the medial dorsal branch of the facet joint.
Background
Penetrating head injuries with impacted foreign bodies are rare, associated with a high incidence of morbidity and potentially life-threatening. In this study, we aimed at investigating ...the outcome of these cases as well as analyzing the factors affecting the prognosis.
Methods
A retrospective study in which the records of 16 patients who had penetrating head injuries caused by low-velocity impacted foreign bodies were revised. All patients were males with a mean age of 28.9 years (range, 18 to 50 years). The follow-up period ranged from 4 to 13 months with a mean of 8.1 months. Causes of injury were construction accidents in 6 (37.5 %) patients, assault in 6 (37.5 %) and road traffic accidents in 4 (25 %). The impacted objects included a bar of iron, a piece of wood, a nail, a sickle and a piece of glass. Diagnostic computerized tomography (CT) of the brain was carried out on admission in all patients. Thirteen (81.3 %) patients were submitted to surgery, and all had the appropriate management in the form of antibiotics and dehydrating measures as required. The primary outcome measure was the Glasgow Outcome Scale (GOS) at the end of follow-up.
Results
At the end of follow-up, ten (62.5 %) patients had a GOS score of 5, two (12.5 %) patients had a score of 4, and four (25 %) patients had a score of 1.
Conclusions
Low-velocity penetrating head injuries are most common in young adult males. With the appropriate management, a majority of even the most severe cases can have a favorable outcome.
Star forage chopper machine (SFCM) was modified and tested to reduce the power required and to improve forage cutting efficiency, also, it will reduce the environmental and health impacts by ...replacing diesel-based farm machines with electrically operated ones. Power transmission assembly, rotating cutter head knives and straw outlet position modified, and newly constructed feed rollers were added and positioned to control plant material chopping process. The performance of SFCM was evaluated based on its ability to chop rice straw and cotton stalks under three different feed rates 0.8, 1.2 and 1.5 t/h four different knife speed, 78.6 (750), 91.1 (1000), 115.2 (1250) and 136.2 (1500) m/s (rpm). Minimum cut lengths were 1.35 and 1.27 cm for rice straw and were achieved by using the highest feed rate of 1.5 t/h with the maximum of knife speed 136.2 m/s with using toothed blades and normal (flail) blades respectively. At higher feed rates, either power required cutting rice straw or cotton stalks increased with increasing knife speed under the two types of new knifes. Minimum power required to cut rice straw were 1.81 and 1.76 kW and were achieved by using feeding rate of 0.8 t/h with knife speed of 78.6 m/s for toothed blades and normal (flail) blades respectively. Rice straw and cotton stalks cutting efficiency decreased with increasing feeding rates and increased with increasing knife speeds. Specific energy for cutting rice straw and cotton stalks decreased with increasing feeding rates and decreased also with increasing knife speeds.
CLOSER TO THE FINISH LINE? Moussa, Wael S.
Education finance and policy,
01/2017, Letnik:
12, Številka:
1
Journal Article
Recenzirano
High school graduation rates are a central policy topic in the United States and have been shown to be stagnant for the past three decades. Using student-level administrative data from New York City ...Public Schools, I examine the impact of compulsory school attendance on high school graduation rates and grade attainment, focusing the analysis on ninth and tenth grade cohorts. I exploit the interaction between the school start-age cutoff and compulsory attendance age requirement to identify the effect of compulsory schooling. I find that an additional year in compulsory attendance leads to an increase of 9 to 12 percent in the probability of progressing to grades 11 and 12, and raises the probability of graduating from high school by 9 to 14 percent, depending on the specification.
Background
Large intraventricular tumors (IVTs) impose technical and surgical challenges, due to their enormous sizes, mass effect, vast extensions, and vascularity.
Objective
The authors aim at ...presenting their results, clinical outcomes, and the surgical strategies in the management of large IVTs through transcortical approaches.
Methods
A prospective trial was conducted at the Main Hospital of Alexandria University, Egypt, between August 2018 and October 2020 on 20 patients harboring IVTs larger than 5 cm or bilaterally represented. The variables evaluated included the extent of resection, postoperative neurological deficits, blood loss, surgical approaches, intraoperative challenges, complications, adjuvant therapies, Glasgow Outcome Scale, hydrocephalus, and cerebrospinal fluid (CSF) diversion.
Results
The study included 20 cases (9 males and 11 females). Mean age at diagnosis was 16.1 years (range 1–45). Mean follow-up was 12 months (range 9–26). Primary tumor locations were ventricular body, atrium, temporal horn, and frontal horn in 11, 5, 3, and 1 cases, respectively. Main pathologies were central neurocytomas (7 patients/35%), ependymomas (3 patients/15%), and subependymal giant cell astrocytoma (SEGA) (3 patients/15%). Excision was gross total (
n
= 19) and near-total (
n
= 1). Significant intraoperative bleeding (
n
= 6). Postoperative minor intraventricular hemorrhage (
n
= 6), subdural collections (
n
= 8), hydrocephalus (
n
= 9), memory affection (
n
= 4), and motor deficits (
n
= 4). Postoperative Glasgow Outcome Scale of 5/5 (
n
= 20), no mortalities were recorded. preoperative seizures (
n
= 7), new onset postoperative seizures (
n
= 2).
Conclusion
Surgical approaches to large tumors of the lateral ventricles should be tailored to the variability of tumor locations, dimensions, extensions, and the individual morbid anatomy, in addition to the surgeon’s experience and preferences. Trans-cortical approaches can provide safe surgical corridors to tackle these challenging subtypes of IVTs with good clinical outcomes, tumor resectability rates, and seizure control.
Research has indicated that reading aloud to young students can enhance their foundational reading skills and their reading motivation, but such research has been lacking in African contexts. In this ...study, we assessed the efficacy of story read-aloud lessons in improving students' foundational reading skills in Nigeria. The experiment took place in a cluster randomized trial of 199 schools in Northern Nigeria. In treatment schools, second-grade teachers conducted weekly read-aloud lessons as an addition to the core learning curriculum. In control schools, second-grade teachers implemented only the core curriculum, without weekly read-aloud lessons. We found that story read-alouds led to positive effects on listening comprehension, letter sound recognition, nonword decoding, and reading fluency, with effect sizes between 0.17 and 0.33 standard deviations. These outcomes suggest that enhanced student motivation from read-alouds may enhance text-based skills. To identify the effects of increased teacher experience on read-aloud effectiveness, we employed a two-period difference-in-differences approach. We found that increased teacher experience explained between 26% and 51% of the overall read-aloud effect, depending on the literacy subskill. We also found that the read-aloud effects coupled with increased teacher experience had an equalizing effect on the reading outcomes of students from divergent home literacy environments.
Existing literacy studies in low-income countries heavily emphasize school factors. This article shifts focus, examining how home-based reading resources and interactions predict children’s reading ...via a non-experimental study. Data involve 2,886 children aged 5–13 in Ghana, selected through a two-stage random sampling. Regression analyses show that siblings and parents reading to the child, reading in front of the child, and assisting with studying positively predict children’s acquisition of varying reading skills, measured by the Early Grade Reading Assessment. The availability of home reading resources similarly predicts these outcomes. The results advocate for more literacy investments in homes, extending beyond schools.
•Improving children’s reading achievement is a central policy goal in Ghana.•Ample reading resources and interactions at home improve children’s reading.•Siblings, besides parents, can help create literacy-rich home environments.•Policies should encourage and support families to create such environments.
Veterinary species cilia sense mechanical vibrations and movements in air as well as in water. They allow fish to locate predators and find prey. Cilium participates in detection of sound vibration ...phonons and determines underwater pathways. In this paper a hybrid software tool packages are used to study, analyze, and determine optimum dimensions of MEMS sensor imitating fish cilia.
The availability of powerful Finite-element software such as COMSOL and the new software generations of computer make it possible to investigate the performance of different types of sensor structures and to propose new ones. MEMS Piezoresistive Vector Hydrophone (MPVH) is one of the recent generations of underwater vibration detection and surveillance devices. In this paper basic design structure of MPVH that is found in many research works is modeled and investigated from points of view of sensor parameters, namely sensor sensitivity, frequency response and linearity. A hybrid optimization technique is deduced to attain sensor's best element dimension and performance.
Background Data: Lumbar disc prolapse is a common neurosurgical diagnosis. A trial of medical treatment, bed rest and physiotherapy is tried at first. Surgical treatment is resorted to if ...conservative treatment fails. However, postoperative complications including recurrent lumbar disc prolapse, postlaminectomy spondylolisthesis and failed back syndrome can occur. This is usually caused by instability at the discectomy level. In a trial to reduce these complications, we will use posterior lumbar interbody fusion together with bilateral facet screw fixation implanted during discectomy to reduce postoperative instability. Purpose: To study the effect of posterior lumbar interbody fusion with bilateral facet screw fixation to decrease the incidence of postoperative complications. Study Design: A prospective randomized controlled trial including 40 patients. Patients and Methods: Forty patients diagnosed with lumbar disc prolapse causing sciatic pain with or without lower limb weakness not responding to conservative treatment were included in the study. Twenty patients (group A) was submitted to PLIF together with bilateral facet screw fixation after having conventional lumbar laminectomy and discectomy, while 20 other patients (group B) was submitted only to conventional lumbar laminectomy and discectomy and will be used as controls. Results: None of group A patients had recurrent LDP, while 8 patient of group B had a significant recurrence at the same level that required surgery (P=0.0364). At 2 years follow-up, 3 patients ofgroup A and 14 of group B had persistent LBP, the difference being statistically significant (P=0.0168).Conclusion: Combined posterior lumbar interbody fusion and bilateral facet screw fixation in lumbar disc prolapse is technically easy to be done and significantly reduce the incidence of recurrent lumbar disc prolapsed, as well as the postoperative lumbar instability and chronic low back pain. (2016ESJ108)
Evidence-based ‘best practices’ from high-resource contexts have motivated some early grade literacy programs in developing countries to hire private literacy specialists as coaches for teachers, ...rather than build coaching into the job description of existing system actors, such as school inspectors. This study poses the question, can education system actors with supervisory responsibilities for schools, who are not necessarily literacy specialists, become effective literacy coaches? Using secondary data from a reading program in Nigeria, we use a fixed-effects regression framework to evaluate the relative effectiveness of external subject matter experts and system actors on teaching and learning outcomes. We find that in Nigeria, system actors are as effective at improving both program implementation and teacher performance as externally hired reading experts. Qualitative data from contrasting coaching models in Nigeria and Ghana provide insight into the reasons why school inspectors may be well-suited for coaching.
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