Reasonable Certainty Research Articles

Comparative Performance Evaluation of HEC-HMS and SWAT Models in Stream Flow Simulation: the Case of Bilate and Gidabo Watersheds, Ethiopia

Many hydrological models have been developed to simulate watershed hydrology. However, identifying the most cost-effective and efficient hydrological models for a specific watershed with reasonable certainty becomes difficult. The purpose of this study was to compare the stream flow prediction efficiency of the HEC-HMS and SWAT models, as well as the associated uncertainty, in the Bilate and Gidabo watersheds. Model-sensitive parameters being identified, they were calibrated and validated. The parameter uncertainties were analyzed using Markov Chain Monte Carlo (MCMC) for HEC-HMS and Sequential Uncertainty Fitting version two (SUF-2) for SWAT. In the case of the HEC-HMS model, the results showed that constant loss rate (CR) was the most sensitive parameter, followed by lag time (LT) for both watersheds. SWAT detected ALPHA_BF in the Bilate Watershed and CN_2 in the Gidabo Watershed as the most sensitive parameters. Overall, both models could adequately simulate the hydrology of both watersheds. Despite their similar modeling capabilities, a comparison analysis revealed that the HEC-HMS model outperformed the SWAT model in simulating streamflow in both watersheds. The findings of this study can help potential model users make risk-informed decisions by selecting a representative model and quantifying associated uncertainty in the modeling field.

Towards Forest Condition Assessment: Evaluating Small-Footprint Full-Waveform Airborne Laser Scanning Data for Deriving Forest Structural and Compositional Metrics

Spatial data on forest structure, composition, regeneration and deadwood are required for informed assessment of forest condition and subsequent management decisions. Here, we estimate 27 forest metrics from small-footprint full-waveform airborne laser scanning (ALS) data using a random forest (RF) and automated variable selection (Boruta) approach. Modelling was conducted using leaf-off (April) and leaf-on (July) ALS data, both separately and combined. Field data from semi-natural deciduous and managed conifer plantation forests were used to generate the RF models. Based on NRMSE and NBias, overall model accuracies were good, with only two of the best 27 models having an NRMSE > 30% and/or NBias > 15% (Standing deadwood decay class and Number of sapling species). With the exception of the Simpson index of diversity for native trees, both NRMSE and NBias varied by less than ±4.5% points between leaf-on only, leaf-off only and combined leaf-on/leaf-off models per forest metric. However, whilst model performance was similar between ALS datasets, model composition was often very dissimilar in terms of input variables. RF models using leaf-on data showed a dominance of height variables, whilst leaf-off models had a dominance of width variables, reiterating that leaf-on and leaf-off ALS datasets capture different aspects of the forest and that structure and composition across the full vertical profile are highly inter-connected and therefore can be predicted equally well in different ways. A subset of 17 forest metrics was subsequently used to assess favourable conservation status (FCS), as a measure of forest condition. The most accurate RF models relevant to the 17 FCS indicator metrics were used to predict each forest metric across the field site and thresholds defining favourable conditions were applied. Binomial logistic regression was implemented to evaluate predicative accuracy probability relative to the thresholds, which varied from 0.73–0.98 area under the curve (AUC), where 11 of 17 metrics were >0.8. This enabled an index of forest condition (FCS) based on structure, composition, regeneration and deadwood to be mapped across the field site with reasonable certainty. The FCS map closely and consistently corresponded to forest types and stand boundaries, indicating that ALS data offer a feasible approach for forest condition mapping and monitoring to advance forest ecological understanding and improve conservation efforts.

Robustness of reported postacute health outcomes in children with SARS-CoV-2 infection: a systematic review

ObjectiveTo systematically assess the robustness of reported postacute SARS-CoV-2 infection health outcomes in children.MethodsA search on PubMed and Web of Science was conducted to identify studies published up to 22...

Errors in Initial Pressure Measurement Affect Rate-Transient Analysis

This article, written by JPT Technology Editor Chris Carpenter, contains highlights of paper URTeC 208321, “Effect of Errors in Initial Pressure Measurement on Rate-Transient Analysis in Unconventional Reservoirs,” by Himanshu S. Jha, SPE, Texas A&M University; Aaditya Khanal, The University of Texas at Tyler; and W. John Lee, SPE, Texas A&M University. The paper has not been peer reviewed. This paper presents a mathematical analysis of how incorrect estimates of initial reservoir pressure (pi) may affect rate-transient analysis (RTA) in ultralow-permeability reservoirs. Measured values of pi are rarely available, and the value estimated using alternative approaches, such as a diagnostic fracture injection test (DFIT), can be time-consuming and expensive and also may be inaccurate. In the complete paper, the authors examine what can and cannot be achieved with accuracy when reliable estimates of pi are not available. Introduction RTA and production forecasting using historical production data require flow-regime identification for model parameter calculation. The task of flow-regime identification is best achieved under constant-rate flowing conditions. However, field conditions and operational changes almost always cause flowing bottomhole pressure (BHP) to change during production. Use of rate-normalized pressure (RNP) can help mitigate the effect of changing BHP under smoothly changing conditions. Calculation of RNP requires an accurate estimate of pi, which often is unavailable. The authors’ work shows that the slope of a log-log plot of RNP vs. time or material balance time (MBT) is relatively insensitive to the value of pi. However, a Cartesian plot of RNP vs. timen (where n may be 0.5 for transient linear flow or a different value for more general “power-law behavior”) rotates the expected straight line for different values of pi or used in calculation of RNP. Therefore, the task of flow-regime identification can be achieved with reasonable certainty with only an estimate of initial pressure, but analysis with RNP vs. timen Cartesian plots may be unreliable.

Sobre dos traducciones de la Constitución de los Estados Unidos atribuidas a Mariano Moreno

This work analyzes the problems presented by two manuscripts from the time of the May Revolution with translations of the United States Constitution attributed to Dr. Mariano Moreno. It indicates the provenance of both documents and in what circumstances they were attributed to Dr. Moreno. Then the article presents unknown or scattered evidence that challenges this widespread belief. It reviews some inaccuracies in the historiography and reveals the true author of the version contained in one of these documents that still remains unpublished in private hands. Regarding the second and best known, that is kept in the Treasury of the Argentine National Library, it presents novel arguments that allow with reasonable certainty to question its attribution to Moreno. It proposes alternative attributions according to the available historical documentation, which opens new paths for research and critical reflection on this Argentine constitutional antecedent.

Ratio Between Outsourcing Management Efficiency and Financial Results: Case Study in Brazilian Companies

The objective of this article was to investigate the impact of the efficiency level in the management of outsourcing on corporate financial results. For this, two companies in the industrial sector that adopted the outsourcing method in their operations were selected, considering the period from 2015 to 2019. The research is a descriptive exploratory case study with a quali-quantitative method. For the data collection, an instrument was used consisting of 8 (eight) management process efficiency indicators (iTEPG), 4 (four) analysis criteria and 5 (five) evaluation standards, intended for the formation of the Efficiency Rate. To define the Efficiency Rate, a mathematical model built from the literature studied was used. In order to reach the research objective, analyses were carried out in the financial and management reports, based on the Business Process Outsourcing (BPO) method. The results showed that the negative impacts on these company's financial results are directly related to the low level of efficiency in the BPO management process, and it can be said with reasonable certainty that poor outsourcing management contributes decisively to negatively impact in the financial results of organizations.

The Role of Mid-Regional Proadrenomedullin in the Differential Diagnosis between Culture-Negative and Culture-Positive Sepsis at Emergency Department Admission.

Background: The host response in culture-negative sepsis (CnS) has been marginally explored upon emergency department (ED) admission. It would be of paramount importance to create a clinical prediction rule to support the emergency department physician in identifying septic patients who can be treated with antibiotics immediately without waiting time to draw cultures if they are unlikely to provide useful diagnostic information. Methods: A multivariable logistic regression analysis was applied to identify the independent clinical variables and serum biomarkers of the culture-negative status among 773 undifferentiated septic patients. Those predictors were combined to build a nomogram predictive of CnS. Results: The serum concentrations of six biomarkers, among the eight biomarkers assayed in this study, were significantly lower in the patients with CnS (449) than in those with culture-positive sepsis (324). After correction for co-variates, only mid-regional proadrenomedullin (MR-proADM) was found to be independently correlated with culture-negative status. Absence of diabetes, hemoglobin concentrations, and respiratory source of infection were the other independent clinical variables integrated into the nomogram—its sensitivity and specificity for CnS were 0.80 and 0.79, respectively. Conclusions: Low concentrations of MR-proADM were independently associated with culture-negative sepsis. Our nomogram, based on the MR-proADM levels, did not predict culture-negative status with reasonable certainty in patients with a definitive diagnosis of sepsis at ED admission.

Recovery of damages in the form of lost profits in the USA

Initially American law rejected any possibility of recovering lost profits as consequential damages, but ultimately agreed. The lost profits claim is for net income from lost business activity, less expenses that would have been attributable to that activity. Generally accepted approaches in calculating lost profits are Yardstick method, Before and After method, Projection method. In addition to the mentioned measures it is admissible to use statistical methods: multivariate regression analysis, matching analysis, stratification, analysis of variance, probit analysis, logit analysis, discriminant analysis, factor analysis and so on. Consequential damages aim to put the non-breaching party in the position that they would have been in if the breach had not occurred. The court is to estimate the reasonable size of compensation needed after a breach to restore the offended party losses yet avoid overcompensation. The lost profits award is limited by the principles of foreseeability, certainty, causation and mitigation. The award isreduced when a portion of the promisee’s loss profit is attributable to circumstances that the promisor could not ordinarily foresee (foreseeability). In order for damages to be recoverable, the loss must have been proximately caused by the breach (causation). Damages are not recoverable for loss beyond an amount that the evidence permits to be established with reasonable (certainty). The non-breaching party is to avoid loss wherever possible (mitigation). Also parties are free to include in a contract an exclusion clause which seeks to exclude or restrict their liability to one another in the event of default. All these rules are not rigid. A court may limit damages for consequential damages if it concludes that in the circumstances justice so requires in order to avoid disproportionate compensation. Keywords: consequential damages; lost profits; foreseeability; reasonable certainty; mitigation; causation; exclusion clause.

Predictors of Airway Hyperresponsiveness in Symptomatic Children with Normal Spirometry and Suspicious of Possible Asthma

Background: Asthma diagnosis may be challenging particularly in patients with mild symptoms without an obstructive pattern in spirometry. Detection of airway hyperresponsiveness (AHR) by a positive methacholine challenge (MCC) is still an important diagnostic tool to confirm the presence of asthma with reasonable certainty. However, it is time consuming and could be exhausting for patients. We aimed to identify the predictive factors for AHR in children with respiratory symptoms without obstructive pattern in spirometry. Methods: Data from children who had undergone MCC were analyzed retrospectively. The demographic features of patients along with laboratory results were collected. Results: A total of 123 children with a median age of 10.5 years were enrolled. AHR was detected in 81 children (65.8%). The age of the children with AHR was significantly younger. The prevalences of aeroallergen sensitization, nocturnal cough, wheezing, and a baseline forced expiratory flow at 75% of vital capacity (FEF75) <65% were significantly more frequent in children with AHR. Multivariate logistic regression analysis revealed age, ever wheezing, nocturnal cough, tree pollen allergy, and FEF75 <65% as independent predictors of AHR. A weighted clinical risk score was developed (range, 0–75 points). At a cutoff point of 35, the presence of AHR is predicted with a specificity of 90.5% and a positive predictive value of 91.5%. Conclusion: In children suspected of having asthma, but without an obstructive pattern in the spirometry, combining independent predictors, which can be easily obtained in clinical practice, might be used to identify children with AHR.

Tubercular Retinal Vasculitis: Diagnostic Dilemma and Management Strategies.

Ocular tuberculosis (OTB) is a rare, extrapulmonary manifestation of systemic TB, which has been a global etiology of uveitis for centuries, though concentrated in the developing world. OTB remains difficult to diagnose clinically despite a plethora of conventional and modern investigations. Tubercular retinal vasculitis (TRV) is a common and specific presentation of OTB but is variably defined in the literature in terms of clinical profile and the investigations essential for diagnosis and treatment. Ironically, the need and duration of antitubercular treatment is uncertain for this manifestation of ocular TB. The rationale and utility for corticosteroids is similarly equivocal for TRV. This review attempts to tease out a commonsense approach from the best available evidence and consensus in the literature to suspect, investigate and diagnose TRV with reasonable certainty, and institute appropriate treatment with due ethnic and geographic considerations.

Application of Machine Learning Algorithm in Managing Deviant Consumer Behaviors and Enhancing Public Service.

Consumer-deviant behavior costs global utility firms USD 96 billion yearly, attributable to Non-Technical Losses (NTLs). NTLs affect the operations of power systems by overloading lines and transformers, resulting in voltage imbalances and, thereby, impacting services. They also impact the electricity price paid by the honest customers. Traditional meters constitute 98 % of the total electricity meters in India. This paper argues that while traditional meters have their limitation in checking consumer-deviant behavior, this issue can be resolved with ML-based algorithms. These algorithms can predict suspected cases of theft with reasonable certainty, thereby enabling distribution companies to save money and provide consistent and dependable services to honest customers at reasonable costs. The key learning from this paper is that even if data is noisy, it is possible to create a Machine Learning Model to detect NTL with 80 percentage plus accuracy.

The Use of Postnatal Weight Gain Algorithms to Predict Severe or Type 1 Retinopathy of Prematurity

The currently recommended method for screening for retinopathy of prematurity (ROP) is binocular indirect ophthalmoscopy, which requires frequent eye examinations entailing a heavy clinical workload. Weight gain-based algorithms have the potential to minimize the need for binocular indirect ophthalmoscopy and have been evaluated in different setups with variable results to predict type 1 or severe ROP. To synthesize evidence regarding the ability of postnatal weight gain-based algorithms to predict type 1 or severe ROP. PubMed, MEDLINE, Embase, and the Cochrane Library databases were searched to identify studies published between January 2000 and August 2021. Prospective and retrospective studies evaluating the ability of these algorithms to predict type 1 or severe ROP were included. Two reviewers independently extracted data. This meta-analysis was performed according to the Cochrane guidelines and reported according to the Preferred Reporting Items for Systematic Reviews and Meta-analysis of Diagnostic Test Accuracy Studies (PRISMA-DTA) guidelines. Ability of algorithms to predict type 1 or sever ROP was measured using statistical indices (pooled sensitivity, specificity, and summary area under the receiver operating characteristic curves, as well as pooled negative likelihood ratios and positive likelihood ratios and diagnostic odds ratios). A total of 61 studies (>37 000 infants) were included in the meta-analysis. The pooled estimates for sensitivity and specificity, respectively, were 0.89 (95% CI, 0.85-0.92) and 0.57 (95% CI, 0.51-0.63) for WINROP (Weight, IGF-1 [insulinlike growth factor 1], Neonatal, ROP), 1.00 (95% CI, 0.88-1.00) and 0.60 (95% CI, 0.15-0.93) for G-ROP (Postnatal Growth and ROP), 0.95 (95% CI, 0.71-0.99) and 0.52 (95% CI, 0.36-0.68) for CHOP ROP (Children's Hospital of Philadelphia ROP), 0.99 (95% CI, 0.73-1.00) and 0.49 (95% CI, 0.03-0.74) for ROPScore, 0.98 (95% CI, 0.94-0.99) and 0.35 (95% CI, 0.22-0.51) for CO-ROP (Colorado ROP). The original PINT (Premature Infants in Need of Transfusion) ROP study reported a sensitivity of 0.98 (95% CI, 0.91-0.99) and a specificity of 0.36 (95% CI, 0.30-0.42). The pooled negative likelihood ratios were 0.19 (95% CI, 0.13-0.27) for WINROP, 0.0 (95% CI, 0.00-0.32) for G-ROP, 0.10 (95% CI, 0.02-0.53) for CHOP ROP, 0.03 (95% CI, 0.00-0.77) for ROPScore, and 0.07 (95% CI, 0.03-0.16) for CO-ROP. The pooled positive likelihood ratios were 2.1 (95% CI, 1.8-2.4) for WINROP, 2.5 (95% CI, 0.7-9.1) for G-ROP, 2.0 (95% CI, 1.5-2.6) for CHOP ROP, 1.9 (95% CI, 1.1-3.3) for ROPScore, and 1.5 (95% CI, 1.2-1.9) for CO-ROP. This study suggests that weight gain-based algorithms have adequate sensitivity and negative likelihood ratios to provide reasonable certainty in ruling out type 1 ROP or severe ROP. Given the implications of missing even a single case of severe ROP, algorithms with very high sensitivity (close to 100%) and low negative likelihood ratios (close to zero) need to be chosen to safely reduce the number of unnecessary examinations in infants at lower risk of severe ROP.

Correlation of Respiratory Aerosols and Metabolic Carbon Dioxide

Respiratory aerosols from breathing and talking are an important transmission route for viruses, including severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Previous studies have found that particles with diameters ranging from 10 nm to 145 μm are produced from different regions in the respiratory system and especially smaller particles can remain airborne for long periods while carrying viral RNA. We present the first study in which respiratory aerosols have been simultaneously measured with carbon dioxide (CO2) to establish the correlation between the two concentrations. CO2 concentrations are easily available through low-cost sensors and could be used to estimate viral exposure through this correlation, whereas source-specific aerosol measurements are complicated and not possible with low-cost sensors. The increase in both respiratory aerosols and CO2 was linear over ten minutes in a 2 m3 chamber for all participants, suggesting a strong correlation. On average, talking released more particles than breathing, with 14,600 ± 16,800 min−1 (one-σ standard deviation) and 6210 ± 5630 min−1 on average, respectively, while CO2 increased with 139 ± 33 ppm min−1 during talking and 143 ± 29 ppm min−1 during breathing. Assuming a typical viral load of 7×106 RNA copies per mL of oral fluid, ten minutes of talking and breathing are estimated to produce 1 and 16 suspended RNA copies, respectively, correlating to a CO2 concentration of around 1800 ppm in a 2 m3 chamber. However, viral loads can vary by several orders of magnitude depending on the stage of the disease and the individual. It was therefore concluded that, by measuring CO2 concentrations, only the number and volume concentrations of released particles can be estimated with reasonable certainty, while the number of suspended RNA copies cannot.

Parasite DNA detection in water samples enhances crayfish plague monitoring in asymptomatic invasive populations

Invasive species can facilitate the spread of pathogens by first providing asymptomatic host reservoirs, and then driving disease outbreaks in native populations through pathogen spillover. An example of this are invasive crayfish species in Europe (Faxonius limosus, Pacifastacus leniusculus, Procambarus clarkii), which carry the deadly plague agent (Aphanomyces astaci). Effective disease management requires comprehensive monitoring, however, pathogen detection in carrier populations with low pathogen prevalence and intensities is challenging. We simultaneously collected and analysed crayfish tissue samples of invasive crayfish populations and water samples to compare A. astaci detection in different sample types using quantitative PCR. Combined, the two sampling methods revealed A. astaci presence with DNA concentrations above limit of detection (LOD; the lowest concentration which can be detected with reasonable certainty) in 13 of 23 invasive crayfish populations. In four additional sites, A. astaci DNA concentrations below LOD were found in water. In four populations only were A. astaci concentrations above LOD detected in both sample types and in three populations in concentrations above LOD in tissue but below LOD in water. The likely reason for these discrepancies is the low A. astaci prevalence and concentration in resistant invasive crayfish, which limit detection reliability. Consistency may be improved by timing surveys with seasonal periods of high A. astaci abundance and by increasing water sampling effort. Considering the ease of collecting eDNA samples, compared to crayfish tissue sampling, eDNA methods would facilitate frequent and comprehensive surveys. However, remaining uncertainties in eDNA-based detection reveal the relevance of combining monitoring tools to improve detection of invasive pathogens and their management.

Estimating pavement roughness using a low-cost depth camera

ABSTRACT In a continuation of the Wyoming Technology Transfer Center (WYT2/LTAP) efforts to minimise the costs associated with the pavement condition assessment process, this study examined the capability of a low-cost depth camera (D435i) in measuring the International Roughness Index (IRI) as an indicator of pavement roughness. This study was performed on 48 pavement segments with various lengths and geometric features extracted from the Wyoming local roads database. A computer program was written specifically to control the camera, process the acquired data, and to return the final IRI values. The data was collected at posted speed limits. Noise reduction and hole filling techniques were applied to rectify the acquired depth data. It was found that a D435i depth camera can estimate the IRI of paved roads with a reasonable certainty compared to a standard profiler. The D435i depth camera can explain 83% of the variations in the actual IRI values measured using a standard road profiler. Statistical analysis showed no significant difference between both measurement methods at a 95% confidence level. The proposed approach has the potential to be a baseline for an inexpensive data collection system suitable for local agencies with limited budgets.

1291Adapting a randomized trial design to develop epidemiology studies for pesticide exposure

Abstract Focus of Presentation Pesticides are chemicals, synthetic or natural, used to mitigate damage caused by pests. They play an important role in agriculture and public health. For a pesticide to be put on the market it must undergo a series of tests required by regulatory agencies to show with reasonable certainty that human exposures will not result in harm. Randomized trials are considered the gold standard for epidemiological study design. It is not ethical to conduct such studies to investigate human health outcomes of pesticide exposure. With increasing abundance of observational epidemiological literature there is an opportunity to leverage these studies for regulatory decision making. This presentation will describe a hypothetical randomized trial design to identify opportunities to adapt elements of experimental epidemiology to address some of the challenges unique to studies of health outcomes following pesticide exposure. Findings Elements warranting further development include analytic methods mimicking randomization, blinding, defining control groups, and introducing increased precision to outcome and exposure classifications. Efforts should aim to define generalizability and determine ways to report findings appropriate for regulatory use. Conclusions/Implications Epidemiologists must leverage analytic techniques, and increase dialogue among academics, industry stakeholders and regulators to adapt experimental epidemiology methods to ensure safety of agricultural pesticides. Key messages Work is needed to adapt experimental epidemiological methods to investigate human health outcomes of pesticide exposure. Focus areas for adaptation include randomization, blinding, control selection, exposure and outcome definitions, generalizability, and reporting.

Residues of glyphosate in food and dietary exposure.

Glyphosate is the active ingredient in Roundup® brand nonselective herbicides, and residue testing for food has been conducted as part of the normal regulatory processes. Additional testing has been conducted by university researchers and nongovernmental agencies. Presence of residues needs to be put into the context of safety standards. Furthermore, to appropriately interpret residue data, analytical assays must be validated for each food sample matrix. Regulatory agency surveys indicate that 99% of glyphosate residues in food are below the European maximum residue limits (MRLs) or U.S. Environmental Protection Agency tolerances. These data support the conclusion that overall residues are not elevated above MRLs/tolerances due to agricultural practices or usage on genetically modified (GM) crops. However, it is important to understand that MRLs and tolerances are limits for legal pesticide usage. MRLs only provide health information when the sum of MRLs of all foods is compared to limits established by toxicology studies, such as the acceptable daily intake (ADI). Conclusions from dietary modeling that use actual food residues, or MRLs themselves, combined with consumption data indicate that dietary exposures to glyphosate are within established safe limits. Measurements of glyphosate in urine can also be used to estimate ingested glyphosate exposure, and studies indicate that exposure is <3% of the current European ADI for glyphosate, which is 0.5 mg glyphosate/kg body weight. Conclusions of risk assessments, based on dietary modeling or urine data, are that exposures to glyphosate from food are well below the amount that can be ingested daily over a lifetime with a reasonable certainty of no harm.

Assessing viability of a minimally invasive autopsy technique in ascertaining the probable cause of death in patients who were SARS CoV19 positive at the time of their demise

BackgroundSARS CoV-19 was declared as a pandemic by the World Health Organization (WHO), raising up challenges on various levels ranging from therapeutics to diagnostics. The conventional autopsy technique may pose a health hazard to health care workers. A minimally invasive autopsy technique can diminish this hazard.Materials and methodsBetween August and November 2020, 51 patients who were suffering from Covid-19 at the time of their demise were included. A novel minimally invasive ultrasound-guided technique for procuring tissue samples of major organs was employed which were thereafter subject to histopathological examination. A detailed review of the course in hospital was noted. An analysis was performed to correlate the cause of death ascertained from our minimally invasive technique with the cause of death ascertained clinically.ResultsThere was adequate tissue sampling in 45 cases, where the minimally invasive autopsy technique confirmed the cause of death in all 45 cases (100%) and made it more specific in 5 cases (11.11%).ConclusionMinimally Invasive Autopsy is an easily reproducible technique which has the potential to strengthen the probable the cause of death with reasonable certainty while ensuring safety and ethics.

Comparative Performance Evaluation of HEC-HMS and SWAT Models in Stream Flow Simulation: the Case of Bilate and Gidabo Watersheds, Ethiopia

Many hydrological models have been developed to simulate watershed hydrology. However, identifying the most cost-effective and efficient hydrological models for a specific watershed with reasonable certainty becomes difficult. The purpose of this study was to compare the stream flow prediction efficiency of the HEC-HMS and SWAT models, as well as the associated uncertainty, in the Bilate and Gidabo watersheds. Model-sensitive parameters being identified, they were calibrated and validated. The parameter uncertainties were analyzed using Markov Chain Monte Carlo (MCMC) for HEC-HMS and Sequential Uncertainty Fitting version two (SUF-2) for SWAT. In the case of the HEC-HMS model, the results showed that constant loss rate (CR) was the most sensitive parameter, followed by lag time (LT) for both watersheds. SWAT detected ALPHA_BF in the Bilate Watershed and CN_2 in the Gidabo Watershed as the most sensitive parameters. Overall, both models could adequately simulate the hydrology of both watersheds. Despite their similar modeling capabilities, a comparison analysis revealed that the HEC-HMS model outperformed the SWAT model in simulating streamflow in both watersheds. The findings of this study can help potential model users make risk-informed decisions by selecting a representative model and quantifying associated uncertainty in the modeling field.

A copper alloy light cannon from Grodno: an example of early firearms from Eastern Europe

The paper discusses a recent find of a copper alloy light cannon discovered at the Old Castle in Grodno, Belarus. The research aim was to analyse the artefact in all its possible aspects, including archaeological and historical contexts, possible analogies, and the gun’s technology of manufacture. This latter was done against a broad comparative background of what is known on manufacturing technologies of late medieval and modern period copper alloy firearms. First, the archaeological and historical contexts of the discovery are dealt with. Then, the morphology and typochronology of the cannon are discussed and relevant analogies are proposed. Next, the technology of manufacture of the cannon is studied on the basis of metallographic examinations and EDS analyses of the metal’s elemental composition. It was found out that the artefact had been made of leaded copper. The cannon can be dated with reasonable certainty to the late 14th c., as implied both by the find context, the morphology and the chemical composition of the artefact. Its deposition can be related to fights over the Old Castle in Grodno in this period, waged by Teutonic, Polish and Lithuanian forces. It can tentatively be proposed that the cannon was manufactured in a Teutonic Order’s workshop, but further research is necessary to verify this supposition.