70 research outputs found

    NASA-KSC\u27S Earth Resources Benefits From Space Exploration

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    The purpose of this paper is to identify the nature and scope of earth resources activities at the Kennedy Space Center (KSC). Because of recent developments from space exploration, NASA and KSC have evolved an earth resources program which focuses on applied R&D activities of direct benefit to a variety of federal, state, and local users. The historical development of this program is traced, and several projects are identified with special emphasis on the use of sidelooking airborne radar in several Brevard County, Florida test areas

    Time lagged information theoretic approaches to the reverse engineering of gene regulatory networks

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    Background: A number of models and algorithms have been proposed in the past for gene regulatory network (GRN) inference; however, none of them address the effects of the size of time-series microarray expression data in terms of the number of time-points. In this paper, we study this problem by analyzing the behaviour of three algorithms based on information theory and dynamic Bayesian network (DBN) models. These algorithms were implemented on different sizes of data generated by synthetic networks. Experiments show that the inference accuracy of these algorithms reaches a saturation point after a specific data size brought about by a saturation in the pair-wise mutual information (MI) metric; hence there is a theoretical limit on the inference accuracy of information theory based schemes that depends on the number of time points of micro-array data used to infer GRNs. This illustrates the fact that MI might not be the best metric to use for GRN inference algorithms. To circumvent the limitations of the MI metric, we introduce a new method of computing time lags between any pair of genes and present the pair-wise time lagged Mutual Information (TLMI) and time lagged Conditional Mutual Information (TLCMI) metrics. Next we use these new metrics to propose novel GRN inference schemes which provides higher inference accuracy based on the precision and recall parameters. Results: It was observed that beyond a certain number of time-points (i.e., a specific size) of micro-array data, the performance of the algorithms measured in terms of the recall-to-precision ratio saturated due to the saturation in the calculated pair-wise MI metric with increasing data size. The proposed algorithms were compared to existing approaches on four different biological networks. The resulting networks were evaluated based on the benchmark precision and recall metrics and the results favour our approach. Conclusions: To alleviate the effects of data size on information theory based GRN inference algorithms, novel time lag based information theoretic approaches to infer gene regulatory networks have been proposed. The results show that the time lags of regulatory effects between any pair of genes play an important role in GRN inference schemes

    It's time for a minimum synoptic operation template in patients undergoing laparoscopic cholecystectomy : a systematic review

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    Background Despite the call to enhance accuracy and value of operation records few international recommended minimal standards for operative notes documentation have been described. This study undertook a systematic review of existing operative reporting systems for laparoscopic cholecystectomy (LC) to fashion a comprehensive, synoptic operative reporting template for the future. Methods A search for all relevant articles was conducted using PubMed version of Medline, Scopus and Web of Science databases in June 2021, for publications from January 1st 2011 to October 25th 2021, using the keywords: laparoscopic cholecystectomy AND operation notes OR operative notes OR proforma OR documentation OR report OR narrative OR audio-visual OR synoptic OR digital. Two reviewers (NOC, GMC) independently assessed each published study using a MINORS score of >= 16 for comparative and >= 10 for non-comparative for inclusion. This systematic review followed PRISMA guidelines and was registered with PROSPERO. Synoptic operative templates from published data were assimilated into one "ideal" laparoscopic operative report template following international input from the World Society of Emergency Surgery board. Results A total of 3567 articles were reviewed. Following MINORS grading 25 studies were selected spanning 14 countries and 4 continents. Twenty-two studies were prospective. A holistic overview of the operative procedure documentation was reported in 6/25 studies and a further 19 papers dealt with selective surgical aspects of LC. A unique synoptic LC operative reporting template was developed and translated into Chinese/Mandarin, French and Arabic. Conclusion This systematic review identified a paucity of publications dealing with operative reporting of LC. The proposed new template may be integrated digitally with hospitals' medical systems and include additional narrative text and audio-visual data. The template may help define new OR (operating room) recording standards and impact on care for patients undergoing LC.Peer reviewe

    Operative management of acute abdomen after bariatric surgery in the emergency setting: the OBA guidelines

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    Background: Patients presenting with acute abdominal pain that occurs after months or years following bariatric surgery may present for assessment and management in the local emergency units. Due to the large variety of surgical bariatric techniques, emergency surgeons have to be aware of the main functional outcomes and long-term surgical complications following the most performed bariatric surgical procedures. The purpose of these evidence-based guidelines is to present a consensus position from members of the WSES in collaboration with IFSO bariatric experienced surgeons, on the management of acute abdomen after bariatric surgery focusing on long-term complications in patients who have undergone laparoscopic sleeve gastrectomy and laparoscopic Roux-en-Y gastric bypass. Method: A working group of experienced general, acute care, and bariatric surgeons was created to carry out a systematic review of the literature following the Preferred Reporting Items for Systematic Review and Meta-analysis Protocols (PRISMA-P) and to answer the PICO questions formulated after the Operative management in bariatric acute abdomen survey. The literature search was limited to late/long-term complications following laparoscopic sleeve gastrectomy and laparoscopic Roux-en-Y gastric bypass. Conclusions: The acute abdomen after bariatric surgery is a common cause of admission in emergency departments. Knowledge of the most common late/long-term complications (> 4 weeks after surgical procedure) following sleeve gastrectomy and Roux-en-Y gastric bypass and their anatomy leads to a focused management in the emergency setting with good outcomes and decreased morbidity and mortality rates. A close collaboration between emergency surgeons, radiologists, endoscopists, and anesthesiologists is mandatory in the management of this group of patients in the emergency setting

    3D finite element electrical model of larval zebrafish ECG signals

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    Assessment of heart function in zebrafish larvae using electrocardiography (ECG) is a potentially useful tool in developing cardiac treatments and the assessment of drug therapies. In order to better understand how a measured ECG waveform is related to the structure of the heart, its position within the larva and the position of the electrodes, a 3D model of a 3 days post fertilisation (dpf) larval zebrafish was developed to simulate cardiac electrical activity and investigate the voltage distribution throughout the body. The geometry consisted of two main components; the zebrafish body was modelled as a homogeneous volume, while the heart was split into five distinct regions (sinoatrial region, atrial wall, atrioventricular band, ventricular wall and heart chambers). Similarly, the electrical model consisted of two parts with the body described by Laplace’s equation and the heart using a bidomain ionic model based upon the Fitzhugh-Nagumo equations. Each region of the heart was differentiated by action potential (AP) parameters and activation wave conduction velocities, which were fitted and scaled based on previously published experimental results. ECG measurements in vivo at different electrode recording positions were then compared to the model results. The model was able to simulate action potentials, wave propagation and all the major features (P wave, R wave, T wave) of the ECG, as well as polarity of the peaks observed at each position. This model was based upon our current understanding of the structure of the normal zebrafish larval heart. Further development would enable us to incorporate features associated with the diseased heart and hence assist in the interpretation of larval zebrafish ECGs in these conditions

    Enhanced perioperative care in emergency general surgery:the WSES position paper

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    Enhanced perioperative care protocols become the standard of care in elective surgery with a significant improvement in patients' outcome. The key element of the enhanced perioperative care protocol is the multimodal and interdisciplinary approach targeted to the patient, focused on a holistic approach to reduce surgical stress and improve perioperative recovery. Enhanced perioperative care in emergency general surgery is still a debated topic with little evidence available. The present position paper illustrates the existing evidence about perioperative care in emergency surgery patients with a focus on each perioperative intervention in the preoperative, intraoperative and postoperative phase. For each item was proposed and approved a statement by the WSES collaborative group.</p

    The acute phase management of spinal cord injury affecting polytrauma patients : the ASAP study

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    Publisher Copyright: © 2022, The Author(s).Background: Few data on the management of acute phase of traumatic spinal cord injury (tSCI) in patients suffering polytrauma are available. As the therapeutic choices in the first hours may have a deep impact on outcome of tSCI patients, we conducted an international survey investigating this topic. Methods: The survey was composed of 29 items. The main endpoints of the survey were to examine: (1) the hemodynamic and respiratory management, (2) the coagulation management, (3) the timing of magnetic resonance imaging (MRI) and spinal surgery, (4) the use of corticosteroid therapy, (5) the role of intraspinal pressure (ISP)/spinal cord perfusion pressure (SCPP) monitoring and (6) the utilization of therapeutic hypothermia. Results: There were 171 respondents from 139 centers worldwide. A target mean arterial pressure (MAP) target of 80–90 mmHg was chosen in almost half of the cases [n = 84 (49.1%)]. A temporary reduction in the target MAP, for the time strictly necessary to achieve bleeding control in polytrauma, was accepted by most respondents [n = 100 (58.5%)]. Sixty-one respondents (35.7%) considered acceptable a hemoglobin (Hb) level of 7 g/dl in tSCI polytraumatized patients. An arterial partial pressure of oxygen (PaO2) of 80–100 mmHg [n = 94 (55%)] and an arterial partial pressure of carbon dioxide (PaCO2) of 35–40 mmHg [n = 130 (76%)] were chosen in most cases. A little more than half of respondents considered safe a platelet (PLT) count > 100.000/mm3 [n = 99 (57.9%)] and prothrombin time (PT)/activated partial thromboplastin time (aPTT) < 1.5 times the normal control [n = 85 (49.7%)] in patients needing spinal surgery. MRI [n = 160 (93.6%)] and spinal surgery [n = 158 (92.4%)] should be performed after intracranial, hemodynamic, and respiratory stabilization by most respondents. Corticosteroids [n = 103 (60.2%)], ISP/SCPP monitoring [n = 148 (86.5%)], and therapeutic hypothermia [n = 137 (80%)] were not utilized by most respondents. Conclusions: Our survey has shown a great worldwide variability in clinical practices for acute phase management of tSCI patients with polytrauma. These findings can be helpful to define future research in order to optimize the care of patients suffering tSCI.Peer reviewe

    Acute mesenteric ischemia : updated guidelines of the World Society of Emergency Surgery

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    Acute mesenteric ischemia (AMI) is a group of diseases characterized by an interruption of the blood supply to varying portions of the intestine, leading to ischemia and secondary inflammatory changes. If untreated, this process may progress to life-threatening intestinal necrosis. The incidence is low, estimated at 0.09-0.2% of all acute surgical admissions, but increases with age. Although the entity is an uncommon cause of abdominal pain, diligence is required because if untreated, mortality remains in the range of 50%. Early diagnosis and timely surgical intervention are the cornerstones of modern treatment to reduce the high mortality associated with this entity. The advent of endovascular approaches in parallel with modern imaging techniques is evolving and provides new treatment options. Lastly, a focused multidisciplinary approach based on early diagnosis and individualized treatment is essential. Thus, we believe that updated guidelines from World Society of Emergency Surgery are warranted, in order to provide the most recent and practical recommendations for diagnosis and treatment of AMI.Peer reviewe

    Mitochondrial physiology

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    As the knowledge base and importance of mitochondrial physiology to evolution, health and disease expands, the necessity for harmonizing the terminology concerning mitochondrial respiratory states and rates has become increasingly apparent. The chemiosmotic theory establishes the mechanism of energy transformation and coupling in oxidative phosphorylation. The unifying concept of the protonmotive force provides the framework for developing a consistent theoretical foundation of mitochondrial physiology and bioenergetics. We follow the latest SI guidelines and those of the International Union of Pure and Applied Chemistry (IUPAC) on terminology in physical chemistry, extended by considerations of open systems and thermodynamics of irreversible processes. The concept-driven constructive terminology incorporates the meaning of each quantity and aligns concepts and symbols with the nomenclature of classical bioenergetics. We endeavour to provide a balanced view of mitochondrial respiratory control and a critical discussion on reporting data of mitochondrial respiration in terms of metabolic flows and fluxes. Uniform standards for evaluation of respiratory states and rates will ultimately contribute to reproducibility between laboratories and thus support the development of data repositories of mitochondrial respiratory function in species, tissues, and cells. Clarity of concept and consistency of nomenclature facilitate effective transdisciplinary communication, education, and ultimately further discovery

    Mitochondrial physiology

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    As the knowledge base and importance of mitochondrial physiology to evolution, health and disease expands, the necessity for harmonizing the terminology concerning mitochondrial respiratory states and rates has become increasingly apparent. The chemiosmotic theory establishes the mechanism of energy transformation and coupling in oxidative phosphorylation. The unifying concept of the protonmotive force provides the framework for developing a consistent theoretical foundation of mitochondrial physiology and bioenergetics. We follow the latest SI guidelines and those of the International Union of Pure and Applied Chemistry (IUPAC) on terminology in physical chemistry, extended by considerations of open systems and thermodynamics of irreversible processes. The concept-driven constructive terminology incorporates the meaning of each quantity and aligns concepts and symbols with the nomenclature of classical bioenergetics. We endeavour to provide a balanced view of mitochondrial respiratory control and a critical discussion on reporting data of mitochondrial respiration in terms of metabolic flows and fluxes. Uniform standards for evaluation of respiratory states and rates will ultimately contribute to reproducibility between laboratories and thus support the development of data repositories of mitochondrial respiratory function in species, tissues, and cells. Clarity of concept and consistency of nomenclature facilitate effective transdisciplinary communication, education, and ultimately further discovery
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