Performance investigation of an ambiguity function-shaped waveform (AFSW) using a photonics-based radar system.

In this work, we investigate the performance of an ambiguity function-shaped waveform (AFSW) using a millimeter-wave photonics-based radar system at 100 GHz. An AFSW is a radar waveform whose ambiguity function can be shaped to increase the peak-to-sidelobe ratio (PSR) for better detectability of targets in a desired range/velocity region. To the best of the authors' knowledge, this paper is the first in the literature that investigates the performance of such a waveform in a photonics-based radar system. We experimentally compare the AFSW performance to the conventional frequency-modulated continuous wave (FMCW). The experimental results show the ability of the AFSW to achieve a PSR of 38.35 dB compared to the PSR of 14.5 dB obtained using the conventional FMCW. Moreover, we investigate the effects of some optical system impairments on the AFSW, such as: (i) optical modulator nonlinearity, (ii) optical modulator bias drift, and (iii) sampling offset error between the transmitter and receiver.

Multievent localization for loop-based Sagnac sensing system using machine learning.

In optical sensing applications such as pipeline monitoring and intrusion detection systems, accurate localization of the event is crucial for timely and effective response. This paper experimentally demonstrates multievent localization for long perimeter monitoring using a Sagnac interferometer loop sensor and machine learning techniques. The proposed method considers the multievent localization problem as a multilabel multiclassification problem by dividing the optical fiber into 250 segments. A deep neural network (DNN) model is used to predict the likelihood of event occurrence in each segment and accurately locate the events. The sensing loop comprises 106.245 km of single-mode fiber, equivalent to ∼50 km of effective sensing distance. The training dataset is constructed in simulation using VPItransmissionMaker, and the proposed machine learning model's complexity is reduced by using discrete cosine transform (DCT). The designed DNN is tested for event localization in both simulation and experiment. The simulation results show that the proposed model achieves an accuracy of 99% in predicting the location of one event within one segment error, an accuracy of 95% in predicting the location of one event out of the two within one segment error, and an accuracy of 78% in predicting the location of the two events within one segment error. The experimental results validate the simulation ones, demonstrating the proposed model's effectiveness in accurately localizing events with high precision. In addition, the paper includes a discussion on extending the proposed model to sense more than two events simultaneously.

Strain FBG-Based Sensor for Detecting Fence Intruders Using Machine Learning and Adaptive Thresholding.

This paper demonstrates an intruder detection system using a strain-based optical fiber Bragg grating (FBG), machine learning (ML), and adaptive thresholding to classify the intruder as no intruder, intruder, or wind at low levels of signal-to-noise ratio. We demonstrate the intruder detection system using a portion of a real fence manufactured and installed around one of the engineering college's gardens at King Saud University. The experimental results show that adaptive thresholding can help improve the performance of machine learning classifiers, such as linear discriminant analysis (LDA) or logistic regression algorithms in identifying an intruder's existence at low optical signal-to-noise ratio (OSNR) scenarios. The proposed method can achieve an average accuracy of 99.17% when the OSNR level is <0.5 dB.

A clinically structured and partnered approach to genetic testing in Trinidadian women with breast cancer and their families.

INTRODUCTION: Breast cancer (BC) is the leading cause of cancer death in Caribbean women. Across the Caribbean islands, the prevalence of hereditary breast cancer among unselected breast cancer patients ranges from 5 to 25%. Moreover, the prevalence of BC among younger women and the high mortality in the Caribbean region are notable. This BC burden presents an opportunity for cancer prevention and control that begins with genetic testing among high-risk women. Measured response to positive genetic test results includes the number of preventive procedures and cascade testing in family members. We previously reported data on an active approach to promote cascade testing in the Bahamas and report on preventive procedures showing moderate uptake. Here, we describe a clinically structured and community-partnered approach to the dissemination and follow-up of genetic test results including family counseling for the promotion of risk mitigation strategies and cascade testing in our Trinidadian cohort of patients tested positive for BC predisposition genes. METHODS: As a part of our initial study of BC genetic testing in Trinidad and Tobago, all participants received pre-test counseling including three-generation pedigree and genetic testing for BRCA1/2, PALB2, and RAD51C. The study was approved by the University of Miami IRB and the Ethics Committee of the Ministry of Health, Trinidad and Tobago. We prospectively evaluated a clinically structured approach to genetic counseling and follow-up of BC mutation carriers in Trinidad and Tobago in 2015. The intervention consisted of (1) engaging twenty-nine BC patients with a deleterious gene mutation (probands), and (2) invitation of their at-risk relatives to attend to a family counseling session. The session included information on the meaning of their results, risk of inheritance, risk of cancer, risk-reduction options, offering of cascade testing to family members, and follow-up of proband decision-making over two years. RESULTS: Twenty-four of twenty-nine mutation carriers (82.8%) consented to enroll in the study. At initial pedigree review, we identified 125 at-risk relatives (ARR). Seventy-seven ARR (62%) attended the family counseling sessions; of these, 76 ARR (99%) consented to be tested for their family gene mutation. Genetic sequencing revealed that of the 76 tested, 35 (46%) ARR were carriers of their family mutation. The ARR received their results and were urged to take preventative measures at post-test counseling. At 2-year follow-up, 6 of 21 probands with intact breasts elected to pursue preventive mastectomy (28.5%) and 4 of 20 women with intact ovaries underwent RRSO (20%). CONCLUSIONS: In Trinidad and Tobago, a clinically structured and partnered approach to our testing program led to a significant rate of proband response by completing the intervention counseling session, executing risk-reducing procedures as well as informing and motivating at-risk relatives, thereby demonstrating the utility and efficacy of this BC control program.

A Survey of BRCA1, BRCA2, and PALB2 mutations in women with breast cancer in Trinidad and Tobago.

The mortality rate from breast cancer in the nation of Trinidad and Tobago is among the highest of any country in the Caribbean region. The contribution of inherited gene mutations to the burden of breast cancer in Trinidad and Tobago has not been studied. We examined the prevalence of mutations in three susceptibility genes (BRCA1, BRCA2, and PALB2) in breast cancer patients in Trinidad and Tobago. We studied 268 unselected breast cancer patients from Trinidad and Tobago and looked for mutations across the entire coding sequences of BRCA1, BRCA2, and PALB2. Overall, 28 of 268 patients (10.4 %) had a mutation in one of the three genes, including 15 in BRCA1, ten in BRCA2, two in PALB2, and one in both BRCA2 and PALB2. There were 25 different mutations identified; of these, four mutations were seen in two patients each. Given the high prevalence of mutations, it is reasonable to offer genetic testing for these three genes to all breast cancer patients in Trinidad and Tobago.

The Advanced Trauma Operative Management course--a two student to one faculty model.

BACKGROUND: The internationally recognized Advanced Trauma Operative Management (ATOM) course uses a 1:1 student-to-faculty teaching model. This study examines a two student to one faculty ATOM teaching model. MATERIALS AND METHODS: We randomly assigned 16 residents to four experienced ATOM faculty members. Half started with the one-student model and the other half with the two-student model and then switched using the same faculty. Students and faculty completed forms on the educational value of the two models (1 = very poor; 2 = poor; 3 = average; 4 = good; and 5 = excellent) and identified educational preferences and recommendations. RESULTS: We assigned educational values for the 13 procedures as follows: All faculty rated the one-student model as excellent; six members rated the two-student model as excellent, and seven as good. Students rated 50%-75% as excellent and 12%-44% as good for the two-student model, and 56%-81% as excellent and 12%-44% as good for the one-student model. Given resource constraints, all faculty and 88% of students preferred the two-student model. With no resource constraints, 75% of students and 50% of faculty chose the two-student model. All faculty and students rated both models "acceptable." Overall, 81% of students and 50% of faculty rated the two-student model better. All faculty members recommended that the models be optional; 94% of students recommended that they be either optional (50%) or a two-student model (44%). Performing or assisting on each procedure twice was considered an advantage of the two-student model. CONCLUSIONS: The two-student teaching model was acceptable and generally preferred in this study. With appropriately trained faculty and students, the two-student model is feasible and should result in less animal usage and possibly wider promulgation.

Perception of Survivorship Needs Among Breast Cancer Patients in Trinidad and Tobago.

The perception of survivorship among the cancer communities of the Caribbean is largely unknown. This study focused on determining the perception and interest in cancer survivorship among breast cancer (BC) patients in Trinidad and Tobago, as a preliminary, to introducing a pilot survivorship program and evaluating its impact on this patient population. Participants were given a questionnaire to determine needs, expectations and interest in survivorship care. Baseline measurable outcomes reported in this article include the following: 1. Participants' satisfaction with their medical care follow-up plan (if any), 2. Participants' satisfaction with the amount of information provided by healthcare providers, and 3. Participants' satisfaction with their physician's overall concern about their well-being, ranked on a 5-point Likert scale. Participants also reported on the advice/ guidelines provided by their physicians, after surgery and/or on completion of treatment, what they did to cope with BC, and their expectations of what could have been done to improve the quality of care received. A second questionnaire was then used to measure the level of interest in participating in a Cancer Survivorship Program (CSP) with components such as: nutrition, psychosocial development, spiritual well-being, and yoga and mindfulness. The level of interest was ranked by participants on a 5-point Likert scale. Fifteen themes emerged from participants' responses to the first questionnaire. Nutrition stood out as the module of highest interest, followed by psychosocial development among BC patients.

Prostate Cancer in the Caribbean.

Prostate cancer (PC) is one of the principal causes of cancer death worldwide. The mortality rate for PC in the Caribbean is higher than in many developed countries, and there is a difference in the incidence among the various Caribbean nations. Besides surveillance and screening, these factors increase concerns about genetic and other risk factors causing PC incidence. PC research is limited in scope and regularity in the Caribbean, creating a literature gap. This literature review aims to examine the PC situation in the Caribbean to highlight where further studies are needed. This review includes all available studies on PC in the specified Caribbean population from 1958 to 2023 utilising the keywords "Prostate Cancer and Caribbean" on PubMed, Scopus, and ScienceDirect databases. The information is then structured by Caribbean countries and by seven themes. These themes are PC incidence and mortality, demographics, clinicopathology, genetics, non-genetic risks, diagnosis and treatment, and PC control. The findings demonstrated that countries with low resources are burdened by more severe illnesses with worse PC outcomes. Furthermore, territories with national cancer registries seemed to have enhanced methods for PC management. In conclusion, this review is significant because it provides initial support for researchers, administrators, and planners for PC healthcare. Additionally, it gives an opportunity for further epidemiological analyses that can supply more significant insights into the PC situation in the Caribbean. Further research should focus on prevention strategies and the standardisation of treatment procedures to enhance surveillance and improve patient outcomes.

AEVAE: Adaptive Evolutionary Autoencoder for Anomaly Detection in Time Series.

Anomaly detection (AD) has witnessed substantial advancements in recent years due to the increasing need for identifying outliers in various engineering applications that undergo environmental adaptations. Consequently, researchers have focused on developing robust AD methods to enhance system performance. The primary challenge faced by AD algorithms lies in effectively detecting unlabeled abnormalities. This study introduces an adaptive evolutionary autoencoder (AEVAE) approach for AD in time-series data. The proposed methodology leverages the integration of unsupervised machine learning techniques with evolutionary intelligence to classify unlabeled data. The unsupervised learning model employed in this approach is the AE network. A systematic programming framework has been devised to transform AEVAE into a practical and applicable model. The primary objective of AEVAE is to detect and predict outliers in time-series data from unlabeled data sources. The effectiveness, speed, and functionality enhancements of the proposed method are demonstrated through its implementation. Furthermore, a comprehensive statistical analysis based on performance metrics is conducted to validate the advantages of AEVAE in terms of unsupervised AD.

Association between organ donation awareness and willingness among Saudi university students.

BACKGROUND: As the global incidence of end-stage organ failure increases, the gap between organ donors and recipients continues to widen. This study was conducted to determine the association between organ donation awareness and organ donation willingness among students of a Saudi university. DESIGN AND METHODS: This analytical cross-sectional study was conducted in King Faisal University, Al-Ahsa, Saudi Arabia. Multi-stage stratified random sampling was used to select the required 723 sample size. Estimation of proportion of students who were aware about organ donation and those who were willing to donate their organs was performed using EpiInfo© Version 7. Association between organ donation awareness and willingness was determined using multivariate logistic regression. RESULTS: Nearly 98% of the participants were aware that organ donation saves lives (95% CI: 96.27%-98.53%); 84.09% were aware that Islam allows organ donation (95% CI: 81.25%-86.58%); 64.87% were aware that organ donation is successfully done in Saudi Arabia (95% CI: 61.32%-68.26%); 32.64% were aware that the government gives incentives to the family of an organ donor (95% CI: 29.32%-36.14%). Over half (56.71%) of the students (95% CI: 53.07 - 60.28%) expressed willingness to donate their organs. Positive association was found between awareness on the position of Islam on organ donation (OR=2.7023, p<0.0001) and awareness of that organ donation can be successfully performed in Saudi Arabia (OR=1.9447, p=0.0001). CONCLUSIONS: Awareness that Islam allows organ donation and awareness that organ donation is successfully done in Saudi Arabia increased the students' willingness to donate.

Breast Cancer in the Caribbean.

Breast cancer (BC) is one of the leading causes of death among women globally. In the Caribbean, there is a higher mortality rate compared with North American and European countries which have higher incidence rates. We conducted a literature review to examine the BC dynamic in the Caribbean and determine the areas where further investigations are needed. The PubMed database was used for identifying relevant studies using a combination of specific keyword searches. All studies focusing on BC within the defined Caribbean population were selected for this review. A total of 117 papers were included. The data were organized and presented under the following headings and reported according to the country where available: BC incidence and mortality, patient demographics, clinicopathology, genetics, behavioral risks, diagnosis and treatment, and BC control. Our review uncovered major variability in the incidence, management, etiology, and mortality of BC among Caribbean countries. Low-resource countries are burdened by more advanced disease with expected poorer BC outcomes (i.e., shorter periods of disease-free survival). Countries with established national cancer registries seem to have a better approach to the management of BC. The introduction of cancer treatment programs in association with international nonprofit groups has shown tremendous improvement in quality, accessible cancer care for patients, particularly in low- and middle-income settings. BC research is relatively limited in the Caribbean, lacking in both scope and consistency. The unique Caribbean BC population of diverse ethnicities, environmental influence, immigrants, socioeconomic status, and sociocultural practices allows an optimal opportunity for epidemiological investigations that can provide deeper insights into the status of BC.

Comparison of the accuracy of intraoral digital impression system and conventional impression techniques for multiple implants in the full-arch edentulous mandible.

BACKGROUND: Several impression techniques, especially in combination with computer-aided design and computer-aided manufacturing (CAD/CAM), are used in increasing the accuracy of dental implantology and decreasing patient discomfort. The study was designed to examine the accuracy of the digital impression (DI) of multiple implants with an intraoral scanner (IOS) and compared with that of a conventional impression (CI). MATERIAL AND METHODS: Four dental implants were placed in teeth area #33, #36, #43 and 46# of the mandibular full-arch model. The implanted model was replicated by IOS and CI after fitting of scannable abutments over the implant screws. Then, a small hole was made on the scan region (as a reference point). Two types of CI techniques were used; dual-phase (DP) and monophase (MP). Stone casts were produced through a conventional close tray impression technique using die stone. The casts were scanned with a laboratory scanner. DI was attained by scanning the implanted model with the IOS. The control sample was accomplished by scanning the implanted model directly with a laboratory scanner. Dimensional accuracy was calculated by measuring the distances between the reference points of four measuring parameters as follows; A-B, B-C, C-D, and A-D using CAD software. RESULTS: The mean values and standard deviation between the four parameters of different impression techniques (CI and DI) and the control group showed convergent value. One-way ANOVA test showed all CI techniques, except IOS, showed a significant differences from the control group. CONCLUSIONS: Compared with CI, the IOS was more accurate because no differences were observed between its measurements and those of the control model. CI is simple and reduces patient discomfort when used in fabricating multiple implants and allowing communication with dental technicians. Key words:Dimension accuracy, conventional impressions, digital impressions, multiple implants.

Gene Sequencing for Pathogenic Variants Among Adults With Breast and Ovarian Cancer in the Caribbean.

Importance: Rates of breast and ovarian cancer are high in the Caribbean; however, to date, few published data quantify the prevalence of inherited cancer in the Caribbean population. Objective: To determine whether deleterious variants in genes that characterize the hereditary breast and ovarian cancer syndrome are associated with the development of breast and ovarian cancer in the English- and Creole-speaking Caribbean populations. Design, Setting, and Participants: This multisite genetic association study used data from germline genetic test results between June 2010 and June 2018 in the Bahamas, Cayman Islands, Barbados, Dominica, Jamaica, Haiti, and Trinidad and Tobago. Next-generation sequencing on a panel of 30 genes and multiplex ligation-dependent probe amplification (BRCA1 and BRCA2) were performed. Medical records were reviewed at time of study enrollment. Women and men diagnosed with breast and ovarian cancer with at least 1 grandparent born in the participating study sites were included; 1018 individuals were eligible and consented to participate in this study. Data were analyzed from November 4, 2019, to May 6, 2020. Exposures: Breast and/or ovarian cancer diagnosis. Main Outcomes and Measures: Rate of inherited breast and ovarian cancer syndrome and spectrum and types of variants. Results: Of 1018 participants, 999 (98.1%) had breast cancer (mean [SD] age, 46.6 [10.8] years) and 21 (2.1%) had ovarian cancer (mean [SD] age, 47.6 [13.5] years). Three individuals declined to have their results reported. A total of 144 of 1015 (14.2%) had a pathogenic or likely pathogenic (P/LP) variant in a hereditary breast and ovarian cancer syndrome gene. A total of 64% of variant carriers had P/LP variant in BRCA1, 23% in BRCA2, 9% in PALB2 and 4% in RAD51C, CHEK2, ATM, STK11 and NBN. The mean (SD) age of variant carriers was 40.7 (9.2) compared with 47.5 (10.7) years in noncarriers. Individuals in the Bahamas had the highest proportion of hereditary breast and ovarian cancer (23%), followed by Barbados (17.9%), Trinidad (12%), Dominica (8.8%), Haiti (6.7%), Cayman Islands (6.3%), and Jamaica (4.9%). In Caribbean-born women and men with breast cancer, having a first- or second-degree family member with breast cancer was associated with having any BRCA1 or BRCA2 germline variant (odds ratio, 1.58; 95% CI, 1.24-2.01; P < .001). A BRCA1 vs BRCA2 variant was more strongly associated with triple negative breast cancer (odds ratio, 6.33; 95% CI, 2.05-19.54; P = .001). Conclusions and Relevance: In this study, among Caribbean-born individuals with breast and ovarian cancer, 1 in 7 had hereditary breast and ovarian cancer. The proportion of hereditary breast and ovarian cancer varied by island and ranged from 23% in the Bahamas to 4.9% in Jamaica. Each island had a distinctive set of variants.

Comparing the standardized live trauma patient and the mechanical simulator models in the ATLS initial assessment station.

BACKGROUND: Mechanical simulators may be an acceptable substitute for the live patient model in trauma skills teaching and assessment. We compare these models in the initial assessment station of the Advanced Trauma Life Support (ATLS) course. METHODS: After a pilot project utilizing both models in a provider ATLS course it appeared that the mechanical model would be satisfactory for ATLS teaching and assessment. Instructors (n = 32) and ATLS Students (n = 64) were randomly selected from our database and completed a questionnaire evaluating the patient model and the simulator after viewing a video in which the simulator replaced the patient model. The evaluators indicated whether the patient and simulator models were satisfactory and then compared them by indicating whether there was any difference between the models, indicating which was more challenging, interesting, dynamic, enjoyable, realistic, and better overall. Comments were also written in the evaluation form. RESULTS: All 32 instructors and 64 students indicated that both the patient and simulator models were satisfactory for teaching and testing ATLS resuscitation skills. At least 62 of the 64 students rated the simulator higher in all categories. Two students rated the patient model as more realistic and two noted no difference in terms of being more interesting. All 32 instructors indicated that the simulator was more challenging, interesting, dynamic, and better overall. Two of the 32 instructors indicated that the patient model was more enjoyable and two indicated that there was no difference as far as the models being realistic. Comments included inability to hear breath sounds that were changing in the patient model as opposed to the simulator model, and the simulator was more interesting and dynamic because the hemodynamic and physiologic parameters could be witnessed without being prompted by the instructor. One main concern expressed by the participants was the more costly simulator, and two instructors indicated that the scenarios could be improved to fit the superior capabilities of the simulator. CONCLUSIONS: There was strong support from both students and instructors for the use of the simulator as a satisfactory substitute for the live patient model. The cost of the simulator is considered a significant issue. However, in centers where simulators are readily available, it appears from our data that it is a very satisfactory substitute for the patient model in teaching and assessing trauma resuscitation skills in the ATLS program.

Primary Osteosarcoma of the Breast in a Patient Treated Previously for Invasive Ductal Carcinoma: An Unusual Presentation of a Very Rare Primary Breast Malignancy.

Primary osteogenic sarcoma of the breast is a rare clinical entity with few cases described in the literature. Unfortunately, the prognosis for these patients is poor when compared to invasive carcinomas of the breast. We report a case of a 58-year-old female who developed a primary osteogenic sarcoma of the breast five years after being treated for invasive carcinoma of the ipsilateral breast without the use of radiotherapy.

The standardized live patient and mechanical patient models--their roles in trauma teaching.

BACKGROUND: We have previously demonstrated improved medical student performance using standardized live patient models in the Trauma Evaluation and Management (TEAM) program. The trauma manikin has also been offered as an option for teaching trauma skills in this program. In this study, we compare performance using both models. METHODS: Final year medical students were randomly assigned to three groups: group I (n = 22) with neither model, group II (n = 24) with patient model, and group III (n = 24) with mechanical model using the same clinical scenario. All students completed pre-TEAM and post-TEAM multiple choice question (MCQ) exams and an evaluation questionnaire scoring five items on a scale of 1 to 5 with 5 being the highest. The items were objectives were met, knowledge improved, skills improved, overall satisfaction, and course should be mandatory. Students (groups II and III) then switched models, rating preferences in six categories: more challenging, more interesting, more dynamic, more enjoyable learning, more realistic, and overall better model. Scores were analyzed by ANOVA with p < 0.05 being considered statistically significant. RESULTS: All groups had similar scores (means % +/- SD)in the pretest (group I - 50.8 +/- 7.4, group II - 51.3 +/- 6.4, group III - 51.1 +/- 6.6). All groups improved their post-test scores but groups II and III scored higher than group I with no difference in scores between groups II and III (group I - 77.5 +/- 3.8, group II - 84.8 +/- 3.6, group III - 86.3 +/- 3.2). The percent of students scoring 5 in the questionnaire are as follows: objectives met - 100% for all groups; knowledge improved: group I - 91%, group II - 96%, group III - 92%; skills improved: group I - 9%, group II - 83%, group III - 96%; overall satisfaction: group I - 91%, group II - 92%, group III - 92%; should be mandatory: group I - 32%, group II - 96%, group III - 100%. Student preferences (48 students) are as follows: the mechanical model was more challenging (44 of 48); more interesting (40 of 48); more dynamic (46 of 48); more enjoyable (48 of 48); more realistic (32/48), and better overall model (42 of 48). CONCLUSIONS: Using the TEAM program, we have demonstrated that improvement in knowledge and skills are equally enhanced by using mechanical or patient models in trauma teaching. However, students overwhelmingly preferred the mechanical model.

Predictors of laparotomy and mortality in polytrauma patients with pelvic fractures.

BACKGROUND: The decision to perform laparotomy in blunt trauma patients is often difficult owing to pelvic fractures; however, once the decision is made, delay or failure to perform laparotomy could affect morbidity and mortality. We sought to identify predictors of laparotomy and mortality in polytrauma patients with pelvic fractures. METHODS: We divided 390 blunt polytrauma patients (Injury Severity Score [ISS] >/= 16) with pelvic fractures into laparotomy (n = 56) and nonlaparotomy (n = 334) groups. We assessed the role of the following variables in predicting laparotomy and mortality: age, sex, hypotension, fluid and blood transfusions, positive abdominal computed tomography (CT) scans or focused assessment with sonography for trauma (FAST) examination, pelvic fracture severity and ISS. We analyzed the data using Student t and chi(2) tests, followed by logistic regression analysis. RESULTS: Mortality was higher in the laparotomy group than the nonlaparotomy group (28.6% v. 12.9%; overall mortality 15.1%). The laparotomy group had higher mean ISS (36.9 v. 24.9), higher mean abbreviated injury scores (AIS) for the abdomen (2.6 v. 0.9) and chest (3.4 v. 1.6), lower mean initial hemoglobin levels (105.2 v. 127.0 g/L), higher mean crystalloid (4249 v. 3436 mL) and blood transfusion volumes over 4 hours (12.1 v. 3.9 units), more frequent hypotension (44.6 v. 18.0%) and a higher percentage of positive CT scans (67.9% v. 28.4%) and FAST examination results (42.9% v. 3.3%) than the nonlaparotomy group. Age (mean 53.7 v. 41.5 yr); ISS (mean 39.0 v. 24.4); AIS for the head (mean 3.2 v. 1.7), abdomen (mean 1.6 v. 1.1), chest (mean 2.7 v. 1.8) and pelvis (mean 3.1 v. 2.6); crystalloid (mean 5157.3 v. 3266.4 mL) and blood transfusion volumes over 4 hours (mean 13.1 v. 3.7) and initial hypotension (61% v. 14.8%) were all greater among patients who died than those who survived. Mean initial hemoglobin levels were lower among patients who died than among those who survived (111.1 v. 126.2 g/L). Age, the AIS for the head, initial hypotension and low initial hemoglobin levels were highly predictive of mortality, whereas low initial hemoglobin levels, a positive FAST examination and high AIS for the abdomen and chest were all highly predictive of laparotomy. CONCLUSION: Among the polytrauma patients with pelvic fractures, 14.3% underwent laparotomy, and mortality was higher among these patients than among those who did not have the procedure. The predictors of laparotomy and mortality are similar to those anticipated in patients without pelvic fractures.

Efficacy of a Novel Surgical Manikin for Simulating Emergency Surgical Procedures.

The practical component of the Advanced Trauma Life Support (ATLS®) course typically includes a TraumaMan® manikin. This manikin is expensive; hence, a low-cost alternative (SurgeMan®) was developed in Brazil. Our primary objective was to compare user satisfaction among SurgeMan, TraumaMan, and porcine models during the course. Our secondary objective was to determine the user satisfaction scores for SurgeMan. This study included 36 ATLS students and nine instructors (4:1 ratio). Tube thoracostomy, cricothyroidotomy, pericardiocentesis, and diagnostic peritoneal lavage were performed on all the three models. The participants then rated their satisfaction both after each activity and after the course. The porcine and TraumaMan models fared better than SurgeMan for all skills except pericardiocentesis. In the absence of ethical or financial constraints, 58 per cent of the students and 66 per cent of the instructors indicated preference for the porcine model. When ethical and financial factors were considered, no preference was evident among the students, whereas 66 per cent of instructors preferred SurgeMan over the others. The students gave all three models an overall adequacy rating of >80 per cent; the instructors gave only the animal models an adequacy rating of <80 per cent. Although the users were more satisfied with TraumaMan than with SurgeMan, both were considered acceptable for the ATLS course.

Molecular spectroscopic study of river nile sediment in the greater cairo region.

The greater Cairo region is the most populated area in Egypt. The aquatic environment of the Nile River in this area is being affected by industrial activities. The study of the molecular structure of sediment may provide a good trace for such changes. Both Fourier transform infrared spectroscopy (FT-IR) and density functional theory (DFT) were used to study the effect of industrial waste disposal south of Cairo on the molecular structure of Nile River sediment. Four seasonal samples were collected from six sites covering 75 km along the Nile River. Grain sizes of 200 microm, 125 microm, 65 microm, and 32 microm, respectively, were examined. The results indicate that hydrated aluminum hydroxide controls the distribution of organic matter in the different grain sizes. Furthermore, the hydration of phenol may take place in grain sizes lower than 200 microm, which is indicated by the OH stretching at 3550 cm(-1) and verified by the obtained model. The formation of metal carboxylate bonds at 1638 cm(-1) (asymmetric) and 1382 cm(-1) (symmetric) indicate the possible interaction between heavy metals and other organic structures, mainly humic substances.

Current concepts in simulation-based trauma education.

The use of simulation-based technology in trauma education has focused on providing a safe and effective alternative to the more traditional methods that are used to teach technical skills and critical concepts in trauma resuscitation. Trauma team training using simulation-based technology is also being used to develop skills in leadership, team-information sharing, communication, and decision-making. The integration of simulators into medical student curriculum, residency training, and continuing medical education has been strongly recommended by the American College of Surgeons as an innovative means of enhancing patient safety, reducing medical errors, and performing a systematic evaluation of various competencies. Advanced human patient simulators are increasingly being used in trauma as an evaluation tool to assess clinical performance and to teach and reinforce essential knowledge, skills, and abilities. A number of specialty simulators in trauma and critical care have also been designed to meet these educational objectives. Ongoing educational research is still needed to validate long-term retention of knowledge and skills, provide reliable methods to evaluate teaching effectiveness and performance, and to demonstrate improvement in patient safety and overall quality of care.