Fishery resource management with migratory prey harvesting in two zones- delay and stochastic approach.

In this work, we looked at a two-zone aquatic habitat where both prey and predators can access the zones. The prey alternates between two zones at random. The growth of prey in the absence of a predator is believed to be logistic in each zone. The inner steady state is determined. Around the interior steady state, the deterministic model's local and global stability is investigated. Furthermore, a stochastic stability study is performed in the neighbourhood of a positive steady state, using analytical estimates of population mean square fluctuations to investigate the system's dynamics in the presence of Gaussian white noise.

A Review Article on Wireless Sensor Networks in View of E-epidemic Models.

Epidemic simulations have recently been used to model the dynamics of malicious codes in the network of wireless sensors. This is because of its open existence, which offers a simple target for malware attacks aimed at disrupting network operations or, worse, causing complete network failure. The Susceptible-Exposed-Infectious-Quarantined-Recovered-Susceptible with Vaccination compartments models like SIR-M, SEIRV, SEIQRV, SEIRS, SITR, SIR with delay are studied by various authors and some of such models that characterize worm dynamics in WSN. After a concise presentation of the wireless sensor network, some primary research consequences of e-pandemic models (of various researchers) are given and assessed. At that point the uses of wireless sensor network in the clinical wellbeing, agribusiness, and military, space and marine investigation are laid out. What's more, we break down the upside of wireless sensor network in these sectors. In this review article, we sum up the fundamental factors that influence the uses of wireless sensor networks in view of e-epidemic models and revived some epidemic models and also discussed some conceivable future works of different epidemic wireless sensor models.

A clinical method for locating the femoral head centre during total knee arthroplasty.

Localisation of the femoral head centre (FHC) during total knee arthroplasty (TKA) is necessary when assessing the overall alignment of the leg using an extramedullary guide for the femur. On-table radiographs for this purpose are time consuming and inconvenient. We describe a clinical method for estimating the FHC: it is marked 1.5 cm lateral to the point where the femoral artery crosses the line joining the pubic tubercle and the anterior superior iliac spine. Using this method the estimated FHC was within 15 mm of the anatomic centre in 84% of cases, and within 24 mm in 99%. This translates into possible knee alignment errors of 2 degrees and 3 degrees, respectively. As alignment error of up to +/-3 degrees is compatible with satisfactory clinical results of TKA, our method provides useful approximation of the FHC. For greater accuracy however, an on-table radiograph is recommended.

Benign meningioma metastasizing through CSF pathways: a case report and review of literature.

Metastasis of intraventricular meningiomas through CSF pathways is a rarity and only 4 cases have been reported in world literature describing meningiomas which were intraventricular and malignant. Here we report a case of benign intraventricular meningioma which had spread through CSF pathways, the recurrences as well as the primary tumor being benign in nature.

Tibial tunnel enlargement following anterior cruciate reconstruction: does post-operative immobilisation make a difference?

The aetiology of tunnel enlargement following anterior cruciate reconstruction is still not fully understood. We studied, with particular reference to the tibial tunnel appearances, a group of 28 patients 1 year from anterior cruciate reconstruction by a four-strand hamstring technique. Fourteen underwent accelerated rehabilitation and 14 were immobilised post-operatively for 2 weeks following reconstruction. Tunnel enlargement was significantly greater in the immobilised group. There was no significant correlation between tunnel enlargement and the clinical result at 1-year post-reconstruction.

Changing concepts in long-term central venous access: catheter selection and cost savings.

BACKGROUND AND OBJECTIVES: Long-term central venous access is becoming an increasingly important component of health care today. Long-term central venous access is important therapeutically for a multitude of reasons, including the administration of chemotherapy, antibiotics, and total parenteral nutrition. Central venous access can be established in a variety of ways varying from catheters inserted at the bedside to surgically placed ports. Furthermore, in an effort to control costs, many traditionally inpatient therapies have moved to an outpatient setting. This raises many questions regarding catheter selection. Which catheter will result in the best outcome at the least cost? It has become apparent in our hospital that traditionally placed surgical catheters (ie, Hickmans and central venous ports) may no longer be the only options. The objective of this study was to explore the various modalities for establishing central venous access comparing indications, costs, and complications to guide the clinician in choosing the appropriate catheter with the best outcome at the least cost. METHODS: We evaluated our institution's central venous catheter use during a 3-year period from 1995 through 1997. Data was obtained retrospectively through chart review. In addition to demographic data, specific information regarding catheter type, placement technique, indications, complications, and catheter history were recorded. Cost data were obtained from several departments including surgery, radiology, nursing, anesthesia, pharmacy, and the hospital purchasing department. RESULTS: During a 30-month period, 684 attempted central venous catheter insertions were identified, including 126 surgically placed central venous catheters, 264 peripherally inserted central catheters by the nursing service, and 294 radiologically inserted peripheral ports. Overall complications were rare but tended to be more severe in the surgical group. Relative cost differences between the groups were significant. Charges for peripherally inserted central catheters were $401 per procedure, compared with $3870 for radiologically placed peripheral ports and $3532 to $4296 for surgically placed catheters. CONCLUSIONS: Traditional surgically placed central catheters are increasingly being replaced by peripherally inserted central venous access devices. Significant cost savings and fewer severe complications can be realized by preferential use of peripherally inserted central catheters when clinically indicated. Cost savings may not be as significant when comparing radiologically placed versus surgically placed catheters. However, significant cost savings and fewer severe complications are associated with peripheral central venous access versus the surgical or radiologic approach.

Persistence and mobility of nitrofen (niclofen, TOK) in mineral and organic soils.

Residues of nitrofen in farm soils, persistence of nitrofen in field microplots, mobility of nitrofen in natural soils and the role of microbial flora in its degradation were studied. Muck soils from vegetable farms in southwestern Ontario contained up to 35 ppm nitrofen in mid-season (August), which decreased to 18 ppm by October. The herbicide was less persistent in sand than in muck. Degradation was slightly faster in sand and muck soils receiving two sprays, than in those sprayed once. From an initial deposit of ca. 2 and 10 ppm resp., in sand and muck field microplots, ca. 2 and 15% persisted after 16 wk. Leaching of nitrofen by water through sand was negligible, and it was even more strongly adsorbed onto organic soil. Natural microbial flora seemed to play an important role in the degradation of nitrofen in soil. Ca. 15 and 38% resp., of the initial concentration persisted in natural sandy loam and muck 16 wk after treatment at 10 ppm, whereas about 94 and 82% resp., persisted in sterilized sandy loam and muck at the same period.

Relative toxicity of endosulfan, its isomers, and formulated products to the freshwater fish Labeo rohita.

The relative toxicity of endosulfan, its isomers, and formulated products to the freshwater fish Labeo rohita was tested. The 96-h LC50 values showed that toxicity decreased in the following order: isomer A, 35% emulsifiable concentrate, technical endosulfan, 4% dust, and isomer B. The principal method of detoxification was by formation of endosulfan ether in the liver, Endosulfant, at both sublethal and lethal doses, enhanced oxygen consumption in L. rohita. Histological studies showed minor changes in the liver only.