ObjectiveOn May 1, 1996, Ontario, Canada, amended the Liquor Licence Act to extend the hours of alcohol sales and service in licensed establishments from 1 AM to 2 AM. The purpose of this study was to evaluate the impact of extended... more
ObjectiveOn May 1, 1996, Ontario, Canada, amended the Liquor Licence Act to extend the hours of alcohol sales and service in licensed establishments from 1 AM to 2 AM. The purpose of this study was to evaluate the impact of extended drinking hours in Ontario on motor-vehicle collision (MVC) and other injuries admitted to regional trauma units based on Ontario Trauma Registry data.MethodA quasi-experimental design using interrupted time series was used to assess changes in admissions to Ontario trauma units. The analyzed data sets were monthly data on number of admissions from MVC and other causes of injury during the 11 PM-12 AM, 12-1 AM, 1–2 AM, and 2–3 AM time windows for 4 years before and 3 years after the policy change (May 1992-April 1999).ResultsFor MVC injuries, no significant pre-post increases were found for the 2–3 AM period commensurate with the introduction of the extended drinking hours, but decreases were found for the 11 PM-12 AM and 1–2 AM periods. For non-MVC injuries, a significant increase was found for the 2–3 AM period.ConclusionsThe data sets suggest that increased availability of alcohol as a result of extension of closing hours had an impact on non-MVC injuries presenting to Ontario trauma units, but road safety initiatives may have mediated the effects of the extension on MVC injuries. These observations are consistent with those of other studies of small changes in alcohol availability.
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ABSTRACT Crops of winter barley (Hordeum vulgare L.) and winter wheat (Triticum aestivum L.) have been exposed to sulphur dioxide (SO2) concentrations in the range 5–58 nl l−1 using an open-air fumigation system. The treatments did not... more
ABSTRACT Crops of winter barley (Hordeum vulgare L.) and winter wheat (Triticum aestivum L.) have been exposed to sulphur dioxide (SO2) concentrations in the range 5–58 nl l−1 using an open-air fumigation system. The treatments did not have consistent effects on growth and yield but produced a range of crop responses in different years that could be related to the influence of meteorological conditions, saprophytic and parasitic micro-organisms and insect pests. Recent measurements indicating a co-deposition of ammonia (NH3) with SO2 treatments in the open-air may also explain some of these observations. Changes in pest and disease occurrence and the requirement and cost for agrochemical treatments to control them should always be considered when evaluating the economic importance of air pollutant exposure.
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ABSTRACT
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ABSTRACT Stochastic weather generators have evolved as tools for creating long time series of synthetic meteorological data at a site for risk assessments in hydrologic and agricultural applications. Recently, their use has been extended... more
ABSTRACT Stochastic weather generators have evolved as tools for creating long time series of synthetic meteorological data at a site for risk assessments in hydrologic and agricultural applications. Recently, their use has been extended as downscaling tools for climate change impact assessments. Non-parametric weather generators, which typically use a K-nearest neighbour (K-NN) resampling approach, require no statistical assumptions about probability distributions of variables and can be easily applied for multi-site use. Two characteristics of traditional K-NN models result from resampling daily values: (1) temporal correlation structure of daily temperatures may be lost, and (2) no values less than or exceeding historical observations can be simulated. Temporal correlation in simulated temperature data is important for hydrologic applications. Temperature is a major driver of many processes within the hydrologic cycle (for example, evaporation, snow melt, etc.) that may affect flood levels. As such, a new methodology for simulation of climate data using the K-NN approach is presented (named KnnCAD Version 4). A block resampling scheme is introduced along with perturbation of the reshuffled daily temperature data to create 675 years of synthetic historical daily temperatures for the Upper Thames River basin in Ontario, Canada. The updated KnnCAD model is shown to adequately reproduce observed monthly temperature characteristics as well as temporal and spatial correlations while simulating reasonable values which can exceed the range of observations. Copyright © 2012 John Wiley & Sons, Ltd.
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In Uganda, control of vector-borne diseases is mainly in form of vector control, and chemotherapy. There have been reports that acaricides are being misused in the pastoralist systems in Uganda. This is because of the belief by scientists... more
In Uganda, control of vector-borne diseases is mainly in form of vector control, and chemotherapy. There have been reports that acaricides are being misused in the pastoralist systems in Uganda. This is because of the belief by scientists that intensive application of acaricide is uneconomical and unsustainable particularly in the indigenous cattle. The objective of this study was to investigate the strategies, rationale and effectiveness of vector-borne disease control by pastoralists. To systematically carry out these investigations, a combination of qualitative and quantitative research methods was used, in both the collection and the analysis of data. Cattle keepers were found to control tick-borne diseases (TBDs) mainly through spraying, in contrast with the control of trypanosomosis for which the main method of control was by chemotherapy. The majority of herders applied acaricides weekly and used an acaricide of lower strength than recommended by the manufacturers. They used very little acaricide wash, and spraying was preferred to dipping. Furthermore, pastoralists either treated sick animals themselves or did nothing at all, rather than using veterinary personnel. Oxytetracycline (OTC) was the drug commonly used in the treatment of TBDs. Nevertheless, although pastoralists may not have been following recommended practices in their control of ticks and tick-borne diseases, they were neither wasteful nor uneconomical and their methods appeared to be effective. Trypanosomosis was not a problem either in Sembabule or Mbarara district. Those who used trypanocides were found to use more drugs than were necessary.
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Metastasis of cancer cells from the primary tumor is associated with poor prognosis and decreased overall survival. One protein implicated in inhibiting metastasis is the tumor metastasis suppressor nonmetastatic protein 23 homologue 1... more
Metastasis of cancer cells from the primary tumor is associated with poor prognosis and decreased overall survival. One protein implicated in inhibiting metastasis is the tumor metastasis suppressor nonmetastatic protein 23 homologue 1 (NM23-H1). NM23-H1 is a multifunctional protein, which, in addition to limiting metastasis, has DNase and histidine protein kinase activities. We have identified new functions for NM23-H1 in
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Since the first description of choanal atresia (CA) in 1755, multiple surgical techniques have been proposed to repair the malformation. Today, the transnasal endoscopic method is the most widely accepted repair technique. The bony... more
Since the first description of choanal atresia (CA) in 1755, multiple surgical techniques have been proposed to repair the malformation. Today, the transnasal endoscopic method is the most widely accepted repair technique. The bony choanal plates are perforated, the lateral choanae are drilled, and a portion of the vomer removed. Unfortunately, the problem of re-stenosis is a significant issue, and as a result, revision surgery may be a recurring theme in some children. We describe a successful revision endoscopic technique utilizing a microdebrider with straight and 120 degrees telescopes, image guided surgery, and topical mitomycin-C to permanently open the choanae without stenting. Described are six children (1-15 years old) with CA or stenosis who have collectively undergone 25 choanal procedures at various institutions. A microdebrider carefully removes the bony septum under direct nasal and intraoral telescopic visualization. No lateral drilling is performed. Image guidance is helpful when excessive scar tissue is present. Topical mitomycin-C minimizes post-operative scarring. The cartilaginous septum is left intact. 2-4-year clinical and endoscopic follow-up on all children revealed a widely patent nasal airway with no complications (epistaxis, crusting, or re-stenosis). Synechiae or re-stenosis did not occur as circumferential mucosal stripping was avoided. No stenting was needed since the bony septum is removed. Near total endoscopic removal of the bony septum provides long-term nasal patency for revision CA/stenosis repairs. The endoscopic 'common choanae' technique is aided by transnasal and transoral telescopic visualization with precise microdebrider removal of the bony septum. The technique is safe with no complications in our case series.
Research Interests: Surgery, Treatment, Treatment Outcome, Adolescent, Instrumentation, and 18 moreEndoscopy, Computer assisted orthopaedic surgery, Humans, Female, Male, Technique, Infant, Pediatric, Clinical Sciences, Topical Drug Administration, Perforation, SURGICAL TECHNIQUE, Debridement, Image Guidance, Image guided surgery, Mitomycin, Nino, and Choanal atresia
Research Interests: Oxidative Stress, Molecular endocrinology, Gene expression, Western blotting, Estrogen Receptor, and 13 moreBiological Sciences, RNA interference, Humans, Potassium, Superoxide Dismutase, Antioxidant enzyme, Fluorescent Antibody Technique, Estrogens, Chromatin Immunoprecipitation, Protein Binding, Superoxides, Breast Cancer Cells, and Estrogen receptor alpha
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Anatomic constraints and instrumentation design characteristics have limited the exploitation of endoscopic surgery in otolaryngology. The move toward less invasive and less morbid procedures has paved the way for the development and... more
Anatomic constraints and instrumentation design characteristics have limited the exploitation of endoscopic surgery in otolaryngology. The move toward less invasive and less morbid procedures has paved the way for the development and application of robotic and computer-assisted systems in surgery. Surgical robotics allows for the use of new instrumentation in our field. We review the operative advantages, limitations, and possible surgical applications of the da Vinci Surgical System in otolaryngology. In the laboratory setting, we explored the setup and use of the da Vinci system in porcine and cadaveric head and neck airway models; the setup was configuredfor optimal airway surgery. Endoscopic cautery, manipulation, and suturing of supraglottic tissues were performed in both the porcine and cadaveric models. We found that the da Vinci system provided the advantages of the lower morbidity associated with endoscopic surgery, more freedom of movement, and three-dimensional open surgical viewing. We also observed that the system has several limitations to use in otolaryngology.
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The da Vinci Surgical System is a new and exciting entrant into the field of robotic technology. This system is undergoing considerable research and is being practically applied in general surgery, cardiothoracic surgery, urology, and... more
The da Vinci Surgical System is a new and exciting entrant into the field of robotic technology. This system is undergoing considerable research and is being practically applied in general surgery, cardiothoracic surgery, urology, and gynecology. We have previously described our experience with the da Vinci system in the laboratory setting, and we have reviewed its potential applications in otolaryngology. Here we present a case report of the first da Vinci-assisted excision of a vallecular cyst in a human. Although we initially encountered some difficulties in the setup, we were able to perform the procedure with moderate ease and without complication. The potential of the da Vinci system in otolaryngology is promising. Further research is needed to explore all of its possible uses in our field.
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Since the first description of choanal atresia (CA) in 1755, multiple surgical techniques have been proposed to repair the malformation. Today, the transnasal endoscopic method is the most widely accepted repair technique. The bony... more
Since the first description of choanal atresia (CA) in 1755, multiple surgical techniques have been proposed to repair the malformation. Today, the transnasal endoscopic method is the most widely accepted repair technique. The bony choanal plates are perforated, the lateral choanae are drilled, and a portion of the vomer removed. Unfortunately, the problem of re-stenosis is a significant issue, and as a result, revision surgery may be a recurring theme in some children. We describe a successful revision endoscopic technique utilizing a microdebrider with straight and 120 degrees telescopes, image guided surgery, and topical mitomycin-C to permanently open the choanae without stenting. Described are six children (1-15 years old) with CA or stenosis who have collectively undergone 25 choanal procedures at various institutions. A microdebrider carefully removes the bony septum under direct nasal and intraoral telescopic visualization. No lateral drilling is performed. Image guidance is...
Research Interests: Surgery, Treatment, Treatment Outcome, Adolescent, Instrumentation, and 18 moreEndoscopy, Computer assisted orthopaedic surgery, Humans, Female, Male, Technique, Infant, Pediatric, Clinical Sciences, Topical Drug Administration, Perforation, SURGICAL TECHNIQUE, Debridement, Image Guidance, Image guided surgery, Mitomycin, Nino, and Choanal atresia
Early diagnosis and treatment of a stroke improves patient outcomes, and knowledge of the cause of the initial event is crucial to identification of the appropriate therapy to maximally reduce risk of recurrence. Assumptions based on... more
Early diagnosis and treatment of a stroke improves patient outcomes, and knowledge of the cause of the initial event is crucial to identification of the appropriate therapy to maximally reduce risk of recurrence. Assumptions based on historical frequency of ischemic subtypes may need revision if stroke subtypes are changing as a result of recent changes in therapy, such as increased use of statins. We analyzed secular trends in stroke risk factors and ischemic stroke subtypes among patients with transient ischemic attack or minor or moderate stroke referred to an urgent transient ischemic attack clinic from 2002 to 2012. There was a significant decline in low-density lipoprotein cholesterol and blood pressure, associated with a significant decline in large artery stroke and small vessel stroke. The proportion of cardioembolic stroke increased from 26% in 2002 to 56% in 2012 (P<0.05 for trend). Trends remained significant after adjusting for population change. With more intensive ...
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Anatomic constraints and instrumentation design characteristics have limited the exploitation of endoscopic surgery in otolaryngology. The move toward less invasive and less morbid procedures has paved the way for the development and... more
Anatomic constraints and instrumentation design characteristics have limited the exploitation of endoscopic surgery in otolaryngology. The move toward less invasive and less morbid procedures has paved the way for the development and application of robotic and computer-assisted systems in surgery. Surgical robotics allows for the use of new instrumentation in our field. We review the operative advantages, limitations, and possible surgical applications of the da Vinci Surgical System in otolaryngology. In the laboratory setting, we explored the setup and use of the da Vinci system in porcine and cadaveric head and neck airway models; the setup was configuredfor optimal airway surgery. Endoscopic cautery, manipulation, and suturing of supraglottic tissues were performed in both the porcine and cadaveric models. We found that the da Vinci system provided the advantages of the lower morbidity associated with endoscopic surgery, more freedom of movement, and three-dimensional open surgi...
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To evaluate the rapid parathyroid hormone assay (rPTH) as a perioperative tool in predicting postoperative symptomatic hypocalcemia following thyroidectomy. We conducted a prospective study of 69 patients undergoing total or completion... more
To evaluate the rapid parathyroid hormone assay (rPTH) as a perioperative tool in predicting postoperative symptomatic hypocalcemia following thyroidectomy. We conducted a prospective study of 69 patients undergoing total or completion thyroidectomy. Rapid PTH levels were obtained preoperatively, intraoperatively, and postoperatively upon arrival in the postanesthesia care unit (PACU). All patients were closely monitored postoperatively for the development of symptomatic or asymptomatic hypocalcemia. Of 60 patients (25%) undergoing thyroidectomy, 15 developed hypocalcemia, 7 (11.7%) were symptomatic, and 8 (13.3%) asymptomatic. An intraoperative rPTH level less than 12 pg/mL was 71% sensitive and 95% specific for predicting postoperative symptomatic hypocalcemia, whereas a PACU rPTH level less than 12 pg/mL was 100% sensitive and 92% specific. A greater than 75% decline in preoperative rPTH level when measured intraoperatively was 71% sensitive and 86% specific, whereas a greater than 75% decline in rPTH level in the PACU was 100% sensitive and 88% specific for predicting symptomatic hypocalcemia. The rPTH assay is a highly accurate and effective tool for predicting symptomatic hypocalcemia immediately after thyroidectomy. Routine utilization of this assay is recommended, because it will allow safe and timely discharge of normocalcemic patients and the early identification of patients requiring treatment of postthyroidectomy hypocalcemia.
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G protein-gated potassium (Kir3) channels are important for controlling neuronal excitability in the brain. Using a proteomics approach, we have identified a unique rodent intracellular protein, sorting nexin 27 (SNX27), which regulates... more
G protein-gated potassium (Kir3) channels are important for controlling neuronal excitability in the brain. Using a proteomics approach, we have identified a unique rodent intracellular protein, sorting nexin 27 (SNX27), which regulates the trafficking of Kir3 channels. Like most sorting nexins, SNX27 possesses a functional PX domain that selectively binds the membrane phospholipid phosphatidylinositol-3-phosphate (PI3P) and is important for trafficking to the early endosome. SNX27, however, is the only sorting nexin to contain a PDZ domain. This PDZ domain discriminates between channels with similar class I PDZ-binding motifs, associating with the C-terminal end of Kir3.3 and Kir3.2c (-ESKV), but not with that of Kir2.1 (-ESEI) or Kv1.4 (-ETDV). SNX27 promotes the endosomal movement of Kir3 channels, leading to reduced surface expression, increased degradation and smaller Kir3 potassium currents. The regulation of endosomal trafficking via sorting nexins reveals a previously unknown mechanism for controlling potassium channel surface expression.
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Research Interests: DNA replication, DNA repair, Molecular endocrinology, Gene expression, Estrogen Receptor, and 16 moreBiological Sciences, Molecular, RNA interference, Humans, Mice, Female, Animals, Deoxyribonucleic Acid, Chromatin Immunoprecipitation, Amino Acid Sequence, Base Sequence, Uterus, Recombinant Proteins, Estradiol, Ovariectomy, and Estrogen receptor alpha
Research Interests: Oxidative Stress, Molecular endocrinology, Gene expression, Western blotting, Estrogen Receptor, and 14 moreBiological Sciences, Molecular, RNA interference, Humans, Potassium, Superoxide Dismutase, Antioxidant enzyme, Fluorescent Antibody Technique, Estrogens, Chromatin Immunoprecipitation, Protein Binding, Superoxides, Breast Cancer Cells, and Estrogen receptor alpha
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Serum creatinine alone can be difficult to interpret as a measure of kidney function such that chronic kidney disease might be under-recognized in the general population. In the province of Ontario, Canada, all outpatient laboratories now... more
Serum creatinine alone can be difficult to interpret as a measure of kidney function such that chronic kidney disease might be under-recognized in the general population. In the province of Ontario, Canada, all outpatient laboratories now report estimated glomerular filtration rate (eGFR) in addition to serum creatinine. To determine the impact of this reporting on clinical practice, we linked health administrative data for more than 8 million adults of age 25 years or older over an almost 10-year period and conducted a population-based intervention analysis with seasonal time-series modeling to determine overall trends in the number and type of patients seen by nephrologists. Compared to the period when only serum creatinines were reported, the number of patients seen in consultation by nephrologists increased after eGFR reporting by an average of 24% (an absolute increase of 2.9 consults per 100,000 adults), an increase of about 23 consults per nephrologist per year. The greatest increases were seen in women (39% increase) and those 80 years of age and older (58% increase). Our study found that eGFR reporting was associated with a sudden increase in the number of nephrology consults. However, it remains to be seen whether the routine reporting of eGFR results in improved treatment and outcomes for those with chronic kidney disease.
Research Interests: Nephrology, Chronic kidney disease, Time series analysis, Clinical Practice, Seasonality, and 17 moreHumans, Kidney, Female, Male, Ontario, Serum Creatinine, Clinical Sciences, Aged, Middle Aged, Adult, Administrative Data, Resource Utilization, General Population, Creatinine, Intervention Analysis, Time Series Model, and Glomerular Filtration Rate
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Research Interests: Immunohistochemistry, Oxidative Stress, Molecular endocrinology, Gene expression, Western blotting, and 15 moreEstrogen Receptor, Molecular, RNA interference, Humans, Ethanol, Immunoprecipitation, Clinical Sciences, Hydrogen Peroxide, Thioredoxin, Chromatin Immunoprecipitation, Veterinary Sciences, Protein Binding, Breast Cancer Cells, Thioredoxin reductase, and Estrogen receptor alpha
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Physician recognition of chronic kidney disease (CKD) in elderly patients has been noted to be poor. These patients are at increased risk of medication dosing errors and acute renal failure. To investigate the effect of reporting... more
Physician recognition of chronic kidney disease (CKD) in elderly patients has been noted to be poor. These patients are at increased risk of medication dosing errors and acute renal failure. To investigate the effect of reporting estimated glomerular filtration rate (GFR) of elderly hospitalized patients on physician recognition of CKD and physician prescribing behaviors. A retrospective combined with a prospective medical record review project. A large academic medical center. Patients included were 65 years of age or older and had creatinine values within the normal laboratory range (&lt; 1.6 mg/dL). Reporting a calculated estimate of GFR to physicians. Rates of recognition of CKD were examined before and after the intervention. The effects of the intervention on prescription of renal-dosed antibiotics and nonsteroidal anti-inflammatory drugs (NSAIDS) and cyclooxygenase- 2 inhibitors (COX-2) at hospital discharge were assessed. A total of 260 and 198 patients were included before and after the intervention, respectively. Recognition of chronic kidney disease was low in both groups but demonstrated a significant increase following reporting of estimated GFR (3.9% to 12.6%, P &lt; .001). Reporting of GFR was not associated with a significant decrease in prescription of NSAID/COX-2 medications or increased rates of correct dosing of antibiotics (P = .10 and P = .81, respectively). Although reporting of estimated GFR was associated with improved physician recognition of CKD in elderly hospitalized patients, it did not lead to a change in physician prescribing. More extensive interventions are necessary to increase recognition and decrease medication dosing errors.
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Research Interests: Surgery, Prospective studies, Humans, Female, Male, and 14 moreYoung Adult, Follow-up studies, Parathyroid Hormone, Clinical Sciences, Aged, Middle Aged, Topical Drug Administration, Adult, Time Factors, Thyroid Diseases, SURGICAL TECHNIQUE, Sodium Chloride, Thyroidectomy, and Predictive value of tests
Research Interests: Dentistry, Surgery, Prediction, Treatment, Calcium, and 24 moreRisk assessment, Probability, Humans, Female, Male, Confidence intervals, Follow-up studies, ENT, Incidence, ROC Curve, Parathyroid Hormone, Registries, Clinical Sciences, Head, Time Factors, Assay, Biological markers, Risk Assessment, Observational Study, Thyroidectomy, Area Under Curve, Predictive value of tests, Cohort Studies, and Postoperative care
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Research Interests: Oxidative Stress, Transcription Factors, Biological Sciences, Saccharomyces cerevisiae, Human Body, and 15 moreNitric oxide, Stress response, Candidiasis, Candida albicans, Fungal Infection, Transcription Factor, Fungal Pathogens, Immune system, Chromatin Immunoprecipitation, Nitrosation, Oral Cavity, Base Sequence, Eukaryotic Cell, Nitric oxide donors, and Host Defense
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Results: Nine patients were excluded from the study. Fifteen of 60 patients (25%) developed postthyroidectomy hypocalcemia, 7 developed laboratory (asymptomatic) hypocalcemia, and 8 developed symptomatic hypocalcemia. The onset of... more
Results: Nine patients were excluded from the study. Fifteen of 60 patients (25%) developed postthyroidectomy hypocalcemia, 7 developed laboratory (asymptomatic) hypocalcemia, and 8 developed symptomatic hypocalcemia. The onset of hypocalcemic symptoms occurred ...
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The function bestglm selects the best subset of inputs for the glm family. The selec- tion methods available include a variety of information criteria as well as cross-validation. Several examples are provided to show that this approach... more
The function bestglm selects the best subset of inputs for the glm family. The selec- tion methods available include a variety of information criteria as well as cross-validation. Several examples are provided to show that this approach is sometimes more accurate than using the built-in R function step. In the Gaussian case the leaps-and-bounds algorithm in leaps is used provided
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Based upon the physical properties of the phenomena being modelled and valid statistical principles, techniques are presented for fitting dynamic models to hydrological time series. Procedures are devised for properly incorporating one or... more
Based upon the physical properties of the phenomena being modelled and valid statistical principles, techniques are presented for fitting dynamic models to hydrological time series. Procedures are devised for properly incorporating one or more covariate series into a dynamic model. ...