23 research outputs found

    Exploiting Data and Human Knowledge for Predicting Wildlife Poaching

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    Poaching continues to be a significant threat to the conservation of wildlife and the associated ecosystem. Estimating and predicting where the poachers have committed or would commit crimes is essential to more effective allocation of patrolling resources. The real-world data in this domain is often sparse, noisy and incomplete, consisting of a small number of positive data (poaching signs), a large number of negative data with label uncertainty, and an even larger number of unlabeled data. Fortunately, domain experts such as rangers can provide complementary information about poaching activity patterns. However, this kind of human knowledge has rarely been used in previous approaches. In this paper, we contribute new solutions to the predictive analysis of poaching patterns by exploiting both very limited data and human knowledge. We propose an approach to elicit quantitative information from domain experts through a questionnaire built upon a clustering-based division of the conservation area. In addition, we propose algorithms that exploit qualitative and quantitative information provided by the domain experts to augment the dataset and improve learning. In collaboration with World Wild Fund for Nature, we show that incorporating human knowledge leads to better predictions in a conservation area in Northeastern China where the charismatic species is Siberian Tiger. The results show the importance of exploiting human knowledge when learning from limited data.Comment: COMPASS 201

    Pre‐symptomatic transmission of novel coronavirus in community settings

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    We used contact tracing to document how COVID‐19 was transmitted across 5 generations involving 10 cases, starting with an individual who became ill on January 27. We calculated the incubation period of the cases as the interval between infection and development of symptoms. The median incubation period was 6.0 days (interquartile range, 3.5‐9.5 days). The last two generations were infected in public places, 3 and 4 days prior to the onset of illness in their infectors. Both had certain underlying conditions and comorbidity. Further identification of how individuals transmit prior to being symptomatic will have important consequences.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/163478/2/irv12773.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/163478/1/irv12773_am.pd

    Development of a World Health Organization International Reference Panel for different genotypes of hepatitis E virus for nucleic acid amplification testing.

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    Globally, hepatitis E virus (HEV) is a major cause of acute viral hepatitis. Epidemiology and clinical presentation of hepatitis E vary greatly by location and are affected by the HEV genotype. Nucleic acid amplification technique (NAT)-based assays are important for the detection of acute HEV infection as well for monitoring chronic cases of hepatitis E. The aim of the study was to evaluate a panel of samples containing different genotypes of HEV for use in nucleic NAT-based assays. The panel of samples comprises eleven different members including HEV genotype 1a (2 strains), 1e, 2a, 3b, 3c, 3e, 3f, 4c, 4g as well as a human isolate related to rabbit HEV. Each laboratory assayed the panel members directly against the 1 World Health Organization (WHO) International Standard (IS) for HEV RNA (6329/10) which is based upon a genotype 3 a strain. The samples for evaluation were distributed to 24 laboratories from 14 different countries and assayed on three separate days. Of these, 23 participating laboratories returned a total of 32 sets of data; 17 from quantitative assays and 15 from qualitative assays. The assays used consisted of a mixture of in-house developed and commercially available assays. The results showed that all samples were detected consistently by the majority of participants, although in some cases, some samples were detected less efficiently. Based on the results of the collaborative study the panel (code number 8578/13) was established as the "1st International Reference Panel (IRP) for all HEV genotypes for NAT-based assays" by the WHO Expert Committee on Biological Standardization. This IRP will be important for assay validation and ensuring adequate detection of different genotypes and clinically important sub-genotypes of HEV

    Mapping the Wind Hazard of Global Tropical Cyclones with Parametric Wind Field Models by Considering the Effects of Local Factors

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    Abstract Tropical cyclones (TCs) cause catastrophic loss in many coastal areas of the world. TC wind hazard maps can play an important role in disaster management. A good representation of local factors reflecting the effects of spatially heterogeneous terrain and land cover is critical to evaluation of TC wind hazard. Very few studies, however, provide global wind hazard assessment results that consider detailed local effects. In this study, the wind fields of historical TCs were simulated with parametric models in which the planetary boundary layer models explicitly integrate local effects at 1 km resolution. The topographic effects for eight wind directions were quantified over four types of terrain (ground, escarpment, ridge, and valley), and the surface roughness lengths were estimated from a global land cover map. The missing TC parameters in the best track datasets were reconstructed with local regression models. Finally, an example of a wind hazard map in the form of wind speeds under a 100-year return period and corresponding uncertainties was created based on a statistical analysis of reconstructed historical wind fields over seven of the world’s ocean basins

    Adaptive Absolute Attitude Determination Algorithm for a Fine Guidance Sensor

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    In order to ensure the attitude determination accuracy and speed of a fine guidance sensor (FGS) in a space telescope with limited onboard hardware computing resources, an adaptive absolute attitude determination algorithm was proposed. The more stars involved in the attitude determination, the higher the attitude accuracy, but more hardware resources will be consumed. By analyzing the relationship between the attitude determination accuracy and the number of stars (NOS) in the field of view (FOV), and the relationship between the detector exposure time and the NOS, an adaptive method of adjusting the NOS in the FOV was proposed to keep the number of observed stars in the FOV of the detector at a target value. The star map recognition algorithm based on improved log-polar transformation has a higher recognition speed than the traditional algorithm but cannot accurately identify and match the corresponding guide star when the number of observed stars is less than the number of guide stars. Thus, a comparison-AND star identification algorithm based on polar coordinates was proposed. In the case of a given line-of-sight pointing and 100-frame image simulation calculation, the root mean square (RMS) value of the line-of-sight pointing error was less than 37 mas in the direction of a right ascension, and less than 25 mas in the direction of declination, as concluded from the experimental simulation

    The impact of different clinicopathologic factors and salvage therapies on cervical cancer patients with isolated para-aortic lymph node recurrence

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    Abstract Background Cervical cancer patients with isolated para-aortic lymph nodes (PALN) recurrence were mainly associated with treatment failure. For these patients, radiotherapy, chemotherapy, surgery ± adjuvant therapy or chemoradiotherapy may be advised, however, no specific therapy has been proposed yet. This study aimed to explore factors influencing the prognosis of cervical cancer cases with isolated PALN recurrence and to find out an effective salvage therapy. Methods Cervical cancer cases with isolated PALN recurrence who received therapies in Zhejiang Cancer Hospital between January 2013 and June 2021 were analyzed retrospectively. Results Carcinoembryonic antigen (CEA) level > 10 ng/mL and positron emission tomography/computed tomography (PET/CT) imaging method used to detect the recurrence were found to be associated with the local control rate. PALN (positive), squamous-cell carcinoma-antigen (SCC-Ag) level (> 10 ng/mL) upon initial diagnosis, and CEA level (> 10 ng/mL), number of metastatic lymph nodes (several) at recurrence were associated with worse survival. Compared with surgery ± adjuvant therapy, chemotherapy (CT) alone or sequential chemoradiotherapy (SCRT) was associated with worse PFS or OS. Concurrent chemoradiotherapy (CCRT) after PALN recurrence could reduce the risk of the second recurrence. 3-year OS of cases after surgery ± adjuvant therapy was the highest (65%), followed by CCRT (45.7%), SCRT (38.9%), radiotherapy (RT) (33.3%), and CT (20.6%). Conclusion In cervical cancer patients with isolated PALN recurrence, chemoradiotherapy or surgery ± adjuvant therapy may be preferred as the salvage treatment

    Identification of factors that impact recurrence in patients with borderline ovarian tumors

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    Abstract Background The lack of consensus around best practices for management of borderline ovarian tumors (BOT) is, in part, to the lack of available data and of clarity in interpreting relationships among various factors that impact outcomes. The objective of this study was to identify clinicopathological factors that impact prognosis of patients with borderline ovarian tumors (BOT) and to address features of this disease with the objective of providing clarity in decision making around management of BOT. Results A total of 178 BOT patients were included in this study, with a median age of 43 years and a median follow-up time of 37 months. Thirty-two (18.0%) recurrences and 5 (2.8%) deaths were observed in this study group. Multivariate analysis showed that fertility-preserving surgery (P = 0.0223 for bilateral cystectomy) and invasive implants (P = 0.0030) were significantly associated with worse PFS, whereas lymphadenectomy (P = 0.0129) was related to improved PFS. No factors were found to be associated with OS due to the limited number of deaths. In addition, patients with serous BOT more commonly had abnormal levels of CA125, while patients with mucinous BOT more commonly had abnormal levels of CEA. Patients with abnormal levels of CA125, or CA19-9, or HE4 had significantly larger tumor sizes. Conclusions Our study reveals the impact of certain types of fertility-preserving surgery, lymphadenectomy and invasive implants on PFS of BOT patients. Blood cancer markers may be associated with histology and size of BOT. Our findings may assist in selection of optimum treatment for BOT patients

    The impact of clinicopathologic and surgical factors on relapse and pregnancy in young patients (≤40 years old) with borderline ovarian tumors

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    Abstract Background Fertility sparing surgery has been extensively performed among patients with borderline ovarian tumors due to their age and favorable prognosis. Nevertheless, the prognosis and obstetric outcomes in these patients remain uncertain. Thus, the current study was carried out to evaluate the oncological safety and fertility benefits of different fertility sparing surgery subtypes and various clinicopathological parameters. Methods Young borderline ovarian tumor patients with an age of ≤40 years, who were admitted and treated in Zhejiang Cancer Hospital from January 1996 to December 2016, were enrolled in this study and reviewed retrospectively. The prognostic and obstetric effects of clinicopathological and surgical variables were evaluated using univariate/multivariate analyses and survival curves. Results A total of 92 eligible patients were enrolled in the analysis. Among these patients, 22 (24%) patients showed recurrence after a median follow-up of 46.5 months. Within the fertility sparing surgery group, patients at advanced stage (≥stage II), of serous type, with micropapillary and bilateral tumors were associated with a higher recurrence rate and a shorter recurrence interval. In terms of different modalities of fertility sparing surgery, adnexectomy was remarkably favored over cystectomy-including (P = 0.012); unilateral salpingo-oophorectomy had better prognosis than cystectomy and bilateral cystectomy was favored over unilateral salpingo-oophorectomy+contralateral cystectomy. Univariate Cox regression analysis indicated that the International Federation of Gynecology and Obstetrics stage (≥Stage II), the presence of bilateral and micropapillary lesions, and the application of cystectomy-including surgery were correlated with poorer disease-free survival, while the mucinous type of borderline ovarian tumors was related to improved disease-free survival. In this study, a total of 22 patients attempted to conceive and 15 (68%) of these patients achieved successful pregnancy. Conclusions Unilateral salpingo-oophorectomy and bilateral cystectomy should be recommended as the preferred choice of treatment for young patients with unilateral and bilateral borderline ovarian tumor who desire to preserve fertility. In addition, borderline ovarian tumor patients at advanced stage (≥stage II), of serous type, with micropapillary and bilateral tumors should pay more attention to the risk of recurrence. Therefore, these patients should choose fertility sparing surgery carefully and attempt to achieve pregnancy as soon as possible

    Additional file 2: eFigure S1. of Relationship between the extent of resection and the survival of patients with low-grade gliomas: a systematic review and meta-analysis

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    Funnel plot for the 5-year mortality for GTR vs STR meta-analysis. The midline of the studies indicates a slight publication bias of studies showing benefit with GTR over STR. (PDF 12 kb
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