ABSTRACT
There is limited evidence regarding the impact of allograft nephrectomy (AN) on the long-term outcome of subsequent kidney re-transplantation compared with no prior allograft nephrectomy. The aim of the present study was to conduct a systematic review and meta-analysis to estimate the accumulation of evidence over time. Primary outcomes were 5-year graft and patient survival. Cochrane library, Google scholar, PubMed, Medline and Embase were systematically searched. Meta-analysis was conducted using both fixed- and random-effects models. Study quality was assessed in duplicate using the Newcastle-Ottawa scale. Sixteen studies were included, with a total of 2256 patients. All included studies were retrospective and comparative. There was no significant difference in 5-year graft survival (GS) [Hazard Ratio (HR) = 1.11, 95% Confidence Intervals (CI): 0.89, 1.38, P = 0.37, I2 = 10%) or in 5-year patient survival (PS; HR = 0.70, 95% CI: 0.45, 1.10, P = 0.12, I2 = 0%]. Patients in the AN cohort were significantly younger than patients in the nonallograft nephrectomy (NAN) cohort by one year. Prior allograft nephrectomy was associated with a significantly higher risk of delayed graft function (DGF), acute rejection, primary nonfunction (PNF), per cent of panel reactive antibodies (% PRA) and allograft loss of the subsequent transplant. Although, DGF, % PRA, acute rejection and primary nonfunction rates were significantly higher in the AN cohort, allograft nephrectomy prior to re-transplantation had no significant association with five-year graft and patient survival.
Subject(s)
Kidney Transplantation , Allografts , Graft Rejection , Graft Survival , Humans , Nephrectomy , Retrospective StudiesABSTRACT
Children learn words through an accumulation of interactions grounded in context. Although many factors in the learning environment have been shown to contribute to word learning in individual studies, no empirical synthesis connects across factors. We introduce a new ultradense corpus of audio and video recordings of a single child's life that allows us to measure the child's experience of each word in his vocabulary. This corpus provides the first direct comparison, to our knowledge, between different predictors of the child's production of individual words. We develop a series of new measures of the distinctiveness of the spatial, temporal, and linguistic contexts in which a word appears, and show that these measures are stronger predictors of learning than frequency of use and that, unlike frequency, they play a consistent role across different syntactic categories. Our findings provide a concrete instantiation of classic ideas about the role of coherent activities in word learning and demonstrate the value of multimodal data in understanding children's language acquisition.
Subject(s)
Child Development/physiology , Learning/physiology , Speech Intelligibility/physiology , Child, Preschool , Female , Humans , Infant , MaleABSTRACT
Studies investigating the development of tense/aspect in children with developmental disorders have focused on production frequency and/or relied on short spontaneous speech samples. How children with developmental disorders use future forms/constructions is also unknown. The current study expands this literature by examining frequency, consistency, and productivity of past, present, and future usage, using the Speechome Recorder, which enables collection of dense, longitudinal audio-video recordings of children's speech. Samples were collected longitudinally in a child who was previously diagnosed with autism spectrum disorder, but at the time of the study exhibited only language delay [Audrey], and a typically developing child [Cleo]. While Audrey was comparable to Cleo in frequency and productivity of tense/aspect use, she was atypical in her consistency and production of an unattested future form. Examining additional measures of densely collected speech samples may reveal subtle atypicalities that are missed when relying on only few typical measures of acquisition.
Subject(s)
Language Development Disorders/diagnosis , Semantics , Social Environment , Video Recording , Autism Spectrum Disorder/diagnosis , Child, Preschool , Comorbidity , Developmental Disabilities/diagnosis , Female , Humans , Linguistics , Longitudinal Studies , Reference Values , Speech Production Measurement , VocabularyABSTRACT
The rapid evolution of the Internet is reshaping the media landscape, with frequent claims of an accelerated and increasingly outraged news cycle. We test these claims empirically, investigating the dynamics of news spread, decay, and sentiment on Twitter (now known as X) compared to talk radio. Analyzing 2019-2021 data including 517,000 hour of radio content and 26.6 million tweets by elite journalists, politicians, and general users, we identified 1694 news events. We find that news on Twitter circulates faster, fades faster, and is more negative and outraged compared to radio, with Twitter outrage also more short-lived. These patterns are consistent across various user types and robustness checks. Our results illustrate an important way social media may influence traditional media: framing and agenda-setting simply by speaking first. As journalism evolves with these media, news audiences may encounter faster shifts in focus, less attention to each news event, and much more negativity and outrage.
ABSTRACT
BACKGROUND: Analysis was performed of two patient cohorts who underwent fixation without fusion for unstable thoracolumbar and lumbar fractures: (I) minimally invasive surgery (MIS) group using combined monoaxial-polyaxial pedicle screws inserted percutaneously; (II) open surgery (OS) group using Schanz screw constructs. Our aim was to compare radiographic and clinical indices of the 'gold standard' of open Schanz screw to MIS monoaxial-polyaxial screw constructs. METHODS: There were 13 patients in the MIS group and 19 in the OS group. Primary outcomes were the correction of fracture angulation and percentage loss of reduction until fracture union. Patient demographics, fracture classification, perioperative data and complications were also collected. RESULTS: There was no significant difference in cohorts when comparing demographics and fracture classification. Operative time was 50 minutes less and haemoglobin drop was 9 g/L less in the MIS group. Radiation exposure was significantly higher in the MIS group. Pre-operatively, the mean kyphotic angle was 22° in the MIS and 16° in the OS group. Both groups achieved similar on-table correction. On immediate postoperative erect radiographs, the MIS group lost 15% of correction vs. 55% in the OS group. At final follow-up, both groups had a further loss of position, but significantly higher in the OS group (28% vs. 96%). CONCLUSIONS: Combined polyaxial-monoaxial screw MIS constructs demonstrate favorable radiological and clinical outcomes for treatment of unstable thoracolumbar and lumbar fractures. Our study also demonstrates higher rates of radiological collapse in the OS cohort.
ABSTRACT
We investigated the differential diffusion of all of the verified true and false news stories distributed on Twitter from 2006 to 2017. The data comprise ~126,000 stories tweeted by ~3 million people more than 4.5 million times. We classified news as true or false using information from six independent fact-checking organizations that exhibited 95 to 98% agreement on the classifications. Falsehood diffused significantly farther, faster, deeper, and more broadly than the truth in all categories of information, and the effects were more pronounced for false political news than for false news about terrorism, natural disasters, science, urban legends, or financial information. We found that false news was more novel than true news, which suggests that people were more likely to share novel information. Whereas false stories inspired fear, disgust, and surprise in replies, true stories inspired anticipation, sadness, joy, and trust. Contrary to conventional wisdom, robots accelerated the spread of true and false news at the same rate, implying that false news spreads more than the truth because humans, not robots, are more likely to spread it.
ABSTRACT
BACKGROUND: To compare the outcome of minimally invasive fracture stabilization to traditional open methods in the thoracolumbar region in patients with an ankylosing disorder of the spine. METHODS: A prospective, ethics-approved database (Spine Tango) at a tertiary referral center was retrospectively reviewed for results of surgery on fractures of the ankylosed thoracolumbar spine. These were then split by surgical technique into two cohorts: minimally invasive surgical fixation (MIS group) or standard open surgery (open group). RESULTS: We identified 17 patients who presented with fractures in an ankylosed spine from 2010 to 2017. MIS fixation was performed on 10 and open surgery and fixation on 7. Average age in the MIS group was older than the traditional cohort. There was no difference in the average number of levels stabilized (open =6.9, MIS =7). There was a shorter duration in the operative time and a significant difference in blood loss in favor of the MIS group (P=0.00079). Radiation exposure time and dose were significantly higher in the MIS group (P=0.006). There were no cases of non-union, implant malposition or failure in either group. Two significant complications occurred with the death of one patient in the MIS group, and one death in the open group. CONCLUSIONS: The MIS technique for fractures of the ankylosed spine has shown an acceptable complication rate and good results comparable to open surgery for a high-risk patient population.
ABSTRACT
We introduce a computational theory of situated language understanding in which the meaning of words and utterances depends on the physical environment and the goals and plans of communication partners. According to the theory, concepts that ground linguistic meaning are neither internal nor external to language users, but instead span the objective-subjective boundary. To model the possible interactions between subject and object, the theory relies on the notion of perceived affordances: structured units of interaction that can be used for prediction at multiple levels of abstraction. Language understanding is treated as a process of filtering perceived affordances. The theory accounts for many aspects of the situated nature of human language use and provides a unified solution to a number of demands on any theory of language understanding including conceptual combination, prototypicality effects, and the generative nature of lexical items. To support the theory, we describe an implemented system that understands verbal commands situated in a virtual gaming environment. The implementation uses probabilistic hierarchical plan recognition to generate perceived affordances. The system has been evaluated on its ability to correctly interpret free-form spontaneous verbal commands recorded from unrehearsed game play between human players. The system is able to "step into the shoes" of human players and correctly respond to a broad range of verbal commands in which linguistic meaning depends on social and physical context. We quantitatively compare the system's predictions in response to direct player commands with the actions taken by human players and show generalization to unseen data across a range of situations and verbal constructions.
ABSTRACT
We have developed components of an automated system that understands and follows navigational instructions. The system has prior knowledge of the geometry and landmarks of specific maps. This knowledge is exploited to infer complex paths through maps based on natural language descriptions. The approach is based on an analysis of verbal commands in terms of elementary semantic units that are composed to generate a probability distribution over possible spatial paths in a map. An integration mechanism based on dynamic programming guides this language-to-path translation process, ensuring that resulting paths satisfy continuity and smoothness criteria. In the current implementation, parsing of text into semantic units is performed manually. Composition and interpretation of semantic units into spatial paths is performed automatically. In the evaluations, we show that the system accurately predicts the speakers' intended meanings for a range of instructions. This paper provides building blocks for a complete system that, when combined with robust parsing technologies, could lead to a fully automatic spatial language interpretation system.
Subject(s)
Algorithms , Artificial Intelligence , Language , Man-Machine Systems , Natural Language Processing , Pattern Recognition, Automated/methods , User-Computer Interface , Geographic Information Systems , Movement , Vocabulary, ControlledABSTRACT
We use words to communicate about things and kinds of things, their properties, relations and actions. Researchers are now creating robotic and simulated systems that ground language in machine perception and action, mirroring human abilities. A new kind of computational model is emerging from this work that bridges the symbolic realm of language with the physical realm of real-world referents. It explains aspects of context-dependent shifts of word meaning that cannot easily be explained by purely symbolic models. An exciting implication for cognitive modeling is the use of grounded systems to 'step into the shoes' of humans by directly processing first-person-perspective sensory data, providing a new methodology for testing various hypotheses of situated communication and learning.
Subject(s)
Cognition/physiology , Computer Simulation , Learning/physiology , Perception/physiology , Communication Methods, Total , Humans , Neural Networks, Computer , PsycholinguisticsABSTRACT
The patient's own palm is used as a template in assessing small patchy burns and is traditionally believed to be 1% of body surface area. This does alter with the patient's age, sex and BMI and there have been suggestions that it can also differ between ethnic groups. We undertook this study to see if there were any differences in the hand surface area between Caucasians, Orientals and Asians. It was done by tracing the hand outline and calculating the surface area. The study showed that there was no significant difference between the three ethnic groups in terms of hand surface area.
Subject(s)
Asian People , Hand/anatomy & histology , Racial Groups , White People , Adolescent , Adult , Anthropometry , Body Mass Index , Body Surface Area , Female , Humans , Male , Middle AgedABSTRACT
Wegener's granulomatosis (WG) causing spinal cord compression is very rare with only few cases reported in literature. We present a case report with review of literature. A 55-year-old lady with known WG presented with acute on chronic spinal cord compression. MRI scan revealed spinal cord compression anteriorly and posteriorly at T2-T5 level. Patient underwent urgent surgical decompression with excision of the posterior dural lesion with synthetic duraplasty. Patient made good neurological recovery. Histopathology revealed features consistent with WG. A rare case of spinal cord compression from WG is presented. Urgent surgical decompression with duraplasty resulted in good neurological outcome.
ABSTRACT
In estimating small areas of burns, it is traditionally taught that the patient's palm is 1% of the body surface area. Whether the palm means the palmar surface of the whole hand or palm excluding the fingers, has not been very clear and is a source of confusion to many junior doctors. The ATLS teaching has been in contradiction to the evidence from literature and hence we undertook a study to examine the evidence and practices regarding this issue. It was done through a literature search, telephonic interviews and a review of Web-pages related to burns area estimation. The results highlighted the existing confusion on the topic and the need for educating junior doctors.
Subject(s)
Burns/pathology , Hand/anatomy & histology , Trauma Severity Indices , Anthropometry/methods , Body Surface Area , Clinical Competence , Female , Humans , Male , Professional Practice , Sex CharacteristicsABSTRACT
To build robots that engage in fluid face-to-face spoken conversations with people, robots must have ways to connect what they say to what they see. A critical aspect of how language connects to vision is that language encodes points of view. The meaning of my left and your left differs due to an implied shift of visual perspective. The connection of language to vision also relies on object permanence. We can talk about things that are not in view. For a robot to participate in situated spoken dialog, it must have the capacity to imagine shifts of perspective, and it must maintain object permanence. We present a set of representations and procedures that enable a robotic manipulator to maintain a "mental model" of its physical environment by coupling active vision to physical simulation. Within this model, "imagined" views can be generated from arbitrary perspectives, providing the basis for situated language comprehension and production. An initial application of mental imagery for spatial language understanding for an interactive robot is described.
Subject(s)
Algorithms , Artificial Intelligence , Communication , Imagination/physiology , Mental Processes/physiology , Natural Language Processing , Robotics/methods , Image Interpretation, Computer-Assisted/methods , Imaging, Three-Dimensional , User-Computer Interface , Vocabulary, ControlledABSTRACT
BACKGROUND: Computed tomography (CT) requires highest radiation doses in radiology. The collective dose from the use of radiation in medicine is rising, partly due to increase in CT use as well as the growing popularity of multislice scanners. There is growing concern from multiple studies that radiation from repeated CT scans could induce malignancies later in life. Patients with hydrocephalus are unique in that they are often subjected to repeated CT imaging throughout their lives to monitor whether their hydrocephalus is under control. We designed a study to see whether a low dose radiation CT protocol could provide effective information for monitoring hydrocephalus. METHODS: A pilot study was done with 10 patients with hydrocephalus who needed CT scanning to monitor their hydrocephalus. The CT protocol was altered for each patient to sequentially bring down the radiation dose to the minimum level, which would provide sufficient diagnostic information. Based on the pilot study, a new low dose CT scanning protocol was devised and tested on 25 shunted patients who needed monitoring of their hydrocephalus. All images were carefully scrutinized by a consultant neuroradiologist and consultant neurosurgeon to ensure that the following diagnostic information could be analyzed: 1. ventricular size, 2. cisterns, 3. sulcii, and 4. cathet er position RESULTS: All low-dose CT images were diagnostically acceptable and provided sufficient information to the requesting clinician. None of the subjects required repeat imaging. The effective radiation dose was reduced from 2.2 mSv using a conventional CT protocol to 0.29 mSv with the new low dose CT protocol. The new CT protocol provides 87% less effective radiation dose compared with conventional scans. CONCLUSIONS: We propose a new low dose CT protocol which can be used for monitoring shunted hydrocephalus. The radiation to the patient with this protocol is comparable to that of a skull X-ray. However, this protocol should only be requested by a clinician who is aware of its limitations.