Drain Openings Research Articles

Endoscopic Endonasal Anterior Skull Base Meningoencephalocele and Cerebrospinal Fluid Leak Repair: Our Intraoperative and Postoperative Protocol and Long-term Outcomes

Abstract Objective We evaluated the long-term outcomes from a single neurosurgeon and otolaryngologist team using a specific operative protocol for repair and postoperative evaluation. Design The charts of patients undergoing endoscopic endonasal repair of meningoencephaloceles (MECs) and cerebrospinal fluid (CSF) leaks were retrospectively reviewed from 2015 to 2023. Intraoperative steps of the repair and reconstruction were analyzed. Patients' postoperative assessments and complications were analyzed. Setting Loyola University Medical Center's electronic medical record database. Participants Forty-three patients (32 female) aged between 11 and 81 years. Main Outcome Measures Long-term outcomes of patients who underwent endoscopic endonasal repair of MECs and CSF leaks by a single team and protocol. We hypothesized that there would be minimal complications and no recurrences, requiring secondary operation. Results The most common site for MECs was the cribriform plate. Lumbar drain opening pressures ranged from 10 to 35 cm H2O with 18 out of 34 patients having the lumbar drain removed immediately postoperatively. The median hospital stay was 3 days. The average length of follow-up was 3.8 years. No recurrences or secondary operations were noted in all patients. One patient had a sinonasal infection that was successfully treated. Eight patients were noted to have venous stenosis and underwent further evaluation. Conclusion This study represents one of the largest long-term analyses of outcomes by a single team. Our specific protocol for the endoscopic endonasal repair of anterior skull base MECs and CSF leaks is safe and effective. These patients should be evaluated and treated for elevated intracranial pressure following the repair.

Improper use of the drain opener poses a serious risk of explosion and poisoning!

Improper use of the drain opener poses a serious risk of explosion and poisoning!

Effects of geotextile envelope and perforations on the performance of corrugated drain pipes

Subsurface drainage is an important agriculture drainage measure. It is primary to select suitable drain pipes and envelopes for efficient subsurface drainage. And now, corrugated drains and geotextile envelopes are widely used. However, the effects of geotextile envelopes and perforations on the drainage of corrugated drains are not well understood. This study conducted a series of sand tank experiments of steady-state flow with or without geotextile envelopes and with different perforation patterns. The drainage flow and the profile head distributions were analyzed and compared. Furthermore, the applicability of theoretical formulas, which are used to calculate effective radius considering the resistance of different perforation patterns, was evaluated. Results showed that the geotextile envelope weakened the effect of perforations on streamlines, thereby causing the value of effective radiuses to be close to that of the actual radius. The drainage flow of the drain with a geotextile envelope was six times that of the bare drain. The relationship between drainage flow and opening area could be described by inverse proportional function. Meanwhile, the drainage flow was affected by the perforation arrangement. Drain with small longitudinal perforation spacing had a drainage flow of approximately 15% larger than that with wider longitudinal perforation spacing. The bottom perforations drained out first and most, and the drainage flow of the drain opened at the bottom could be 11% higher than that at the top. Low-efficiency perforations cause higher head loss near the pipe wall. Existing formulas of entrance resistance were not suitable for geotextile-wrapped corrugated drains, the effect of geotextile envelope and orifice entrance loss at perforations should be considered. Keywords: geotextile envelope, perforation, corrugated drain, effective radius, drain opening, entrance resistance, drainage material DOI: 10.25165/j.ijabe.20231601.7574 Citation: Yang H Y, Wu J W, Guo C Y, Li H, Wu Z. Effects of geotextile envelope and perforations on the performance of corrugated drain pipes. Int J Agric & Biol Eng, 2023; 16(1): 36–44.

ШНЕКОВЫЙ ТРАНСПОРТЕР-РАСПРЕДЕЛИТЕЛЬ ЗЕРНА

The construction of a solar dryer-grain storage facilities is described. The design of a auger conveyor-distributor of grain for its loading is offered. The dependence of the width of the discharge opening in the casing of the auger conveyor-distributor on its length is obtained. The results of laboratory tests of the auger conveyor-distributor of grain are presented. It is established that the minimum initial width of the drain opening for wheat grain should be not less than 9 mm. The conditions of uniform distribution of grain by the auger conveyor-distributor are justified: the filling factor of the auger interturn space in its loading zone – 0.35; the length of the discharge opening of the charging hopper should be equal to the doubled value of the auger pitch size. In this case, the uneven distribution of grain along the discharge opening will be no more than 5%.

Influence of Robust Drain Openings and Insulation Standoffs on Corrosion Under Insulation Behavior of Carbon Steel

Corrosion under insulation (CUI) is among the key concerns for the integrity of process equipment and pipelines. Various measures to detect and fix the damages from CUI pose significant maintenance expenditures in hydrocarbons processing facilities. The key reason behind CUI is the limitation of thermal insulations to absorb the moisture and soak the underneath metal from wicking action. Other than CUI, trapped moisture in the soaked thermal insulations causes heat loss from process systems, thereby posing the risk of additional damage mechanisms and increased operating expenditures. This study addresses the impact of robust drain openings and insulation standoffs on the CUI rate of carbon steel under four different testing conditions, namely isothermal wet, isothermal wet-dry, cyclic wet, and cyclic wet-dry, respectively. Corroded specimens were further characterized using surface topography and scanning electron microscope. The impacts of temperature and moisture cycling on the corrosion attributes were also characterized using the linear polarization resistance method followed by an investigation of corrosion modes via optical microscopy. Insulation standoffs in conjunction with robust drain opening resulted in the lowest corrosion rate. With insulation standoffs and drain openings, the cyclic temperature conditions caused higher metal loss than that in isothermal conditions.

Urine drug-testing tampering approaches: Turkish probationers

The growing numbers of individual and social problems associated with drug abuse necessitate new approaches in drug-testing systems. Equally, drug abusers may attempt to invalidate drug testing using different methods such as adulteration, dilution and substitution. This study aims to investigate tampering methods commonly used by Turkish substance-using probationers and evaluate their effects on toxicological drug-testing results. Initially, probationer urinary screening test results and laboratory substitution documents were evaluated to investigate the dilution and substitution attempt. Additionally, an experimental study was carried out by using readily available household products (bleach, vinegar, drain opener, eye drops) for adulteration. The effect of these agents was investigated for 11-nor-9-carboxy-Δ9-tetrahydrocannabinol (THC-COOH), amphetamine and 3,4-methylenedioxymethamphetamine (MDMA). It was determined that probationers preferred unbranded products (syringes, nylon bottles, etc.) for urine substitution. To detect dilution, screening test results were evaluated along with creatinine values. The variability of mean creatinine values can change the rate of the before-negative and after-positive ratio. For adulteration method, the high amounts of bleach provided false-negative results for THC-COOH and amphetamine, but spiking in any concentration of bleach affected MDMA results, causing a slight increase. Vinegar did not affect the THC-COOH and amphetamine results. However, false-negative results were observed for MDMA, with high amounts of vinegar-spiked urine samples. Drain opener was added in large quantities, and false-negative results were observed for all analytes. Visine eye drops did not have any effect on THC-COOH or amphetamine, but a high quantity of eye drops had a slight decreasing effect for MDMA.

Cutaneous drain opener burns: Report from a tertiary care burns unit

BackgroundChemical burn injuries are generally industrial, but it can happen at home. Drain opener is one of the common causes of this type of burns. Drain openers are available in powder and liquid forms and contain either sodium hydroxide or sulfuric acid which causes burns when it gets in contact with the skin. This article reviews drain opener burns which presented to a tertiary care burns unit. MethodsA retrospective study of all drain opener chemical burns which presented to Khoula hospital, Muscat, Oman between 01.01.2013 and 31.12.2017. ResultsThere were 126 cases of drain opener burns (56% of all chemical burns). 80% of the patients were males. The mean age was 29.6 years. 18% of the patients were children. 93% of the patients had 10% or less of total body surface area (TBSA) affected. Upper limb was most commonly involved followed by lower limb and head and neck area. 37.3% of the patients had superficial dermal burns, 29.4% had mixed superficial and deep dermal burns and 33.3% had deep dermal or full thickness burns. There was no systemic poisoning in any of the cases. One of the patients required escharotomy. Two patients required ventilation. 60% of the patients had first aid given at the time of injury. Washing with tap water was the first aid given for all patients. 38% of the patients required surgery. 38% of the patients had hypertrophic scarring, 14% had hyperpigmented scars and 5% developed contracture. There were no mortalities. ConclusionDrain openers are a common cause of domestic chemical burns in our community. These burns do not usually involve a very large area but can cause significant morbidity. The injury keeps happening despite warning signs on the bottles and the care taken by the users. More awareness needs to be created and clear warning signs must be kept on the bottles in order to reduce this type of injury.

Risk factors for meningitis in neurosurgical patients with cerebrospinal fluid drains: prospective observational cohort study.

Cerebrospinal fluid (CSF) drainage or intracranial pressure (ICP) monitoring devices are life-saving devices. We examined the risk factors for infections related to them and assessed the effect of an infection control (IC) intervention. A prospective observational study was conducted in the Neurosurgical Department of our hospital between 2014 and 2017. We included all consecutive patients undergoing CSF catheter insertions, including external ventricular drainage (EVD), lumbar drainage (LD), and ICP catheters. An IC intervention was implemented between March and August 2016. We examined risk factors for meningitis or ventriculitis, defined according to Healthcare-associated infections surveillance definitions, on univariate and multivariate analysis. A total of 232 patients with 437 drains (212 EVDs, 92 LDs, and 133 ICPs) were included. On univariate and multivariate analysis, the infection incidence was 13.7 per 1000 drain days (17.3/1000 before IC intervention, 7.9/1000 during, and 9.2/1000 after the intervention). Most episodes were caused by Gram-negative bacteria, and the most common pathogen was Acinetobacter baumanii. Risk factors for infection per patient included diabetes mellitus (p = 0.017), CSF leak (p = 0.032), drain opening (p = 0.027), and the duration of the drain in days (p = 0.035). Risk factors per catheter included drain opening (p < 0.001), drain days (p = 0.001), and the IC intervention period compared to before the intervention period (p = 0.037). When restricting the analysis to EVDs, drain days (p = 0.001) was the only significant risk factor. Strict adherence to IC, shortening drain duration, and avoiding unnecessary opening and manipulation of the drains are crucial to preventing neurosurgical drain infections.

Cerebral Vascular Changes During Acute Intracranial Pressure Drop.

This study applied a new external ventricular catheter, which allows intracranial pressure (ICP) monitoring and cerebral spinal fluid (CSF) drainage simultaneously, to study cerebral vascular responses during acute CSF drainage. Six patients with 34 external ventricular drain (EVD) opening sessions were retrospectively analyzed. A published algorithm was used to extract morphological features of ICP recordings, and a template-matching algorithm was applied to calculate the likelihood of cerebral vasodilation index (VDI) and cerebral vasoconstriction index (VCI) based on the changes of ICP waveforms during CSF drainage. Power change (∆P) of ICP B-waves after EVD opening was also calculated. Cerebral autoregulation (CA) was assessed through phase difference between arterial blood pressure (ABP) and ICP using a previously published wavelet-based algorithm. The result showed that acute CSF drainage reduced mean ICP (P = 0.016) increased VCI (P = 0.02) and reduced ICP B-wave power (P = 0.016) significantly. VCI reacted to ICP changes negatively when ICP was between 10 and 25mmHg, and VCI remained unchanged when ICP was outside the 10-25mmHg range. VCI negatively (r = - 0.44) and VDI positively (r = 0.82) correlated with ∆P of ICP B-waves, indicating that stronger vasoconstriction resulted in bigger power drop in ICP B-waves. Better CA prior to EVD opening triggered bigger drop in the power of ICP B-waves (r = - 0.612). This study demonstrates that acute CSF drainage reduces mean ICP, and results in vasoconstriction which can be detected through an index, VCI. Cerebral vessels actively respond to ICP changes or cerebral perfusion pressure (CPP) changes in a certain range; beyond which, the vessels are insensitive to the changes in ICP and CPP.

Evaluation of esophageal injuries secondary to ingestion of unlabeled corrosive substances: pediatric case series.

Esophageal or gastric injuries secondary to caustic substance ingestion is still an important issue in developing countries. Its clinical spectrum can vary from absence of mucosal injury to complications such as severe burns, strictures and perforation. Physical examination and first endoscopic evaluation are very important in the diagnosis. The objective of this study is to present 154 children who were undergone upper gastrointestinal endoscopy because of caustic substance ingestion including descaler, degreaser, unlabeled bleach, drain opener, surface cleaner, dishwasher rinse aid, hydrochloric acid. Sixty-nine children had positive oropharyngeal findings. Sixtythree children were found to have burns in the first endoscopic examination and forty of these burns were severe burn. In the follow-up, twenty children developed strictures that were undergone dilatation program. Fourteen children in the dilatation program had successful dilatation and intralesional steroid injection. However three children had undergone colonic interposition and three undergone laparoscopic gastroduodenostomy and gastrojejunostomy.

Measuring temperature in GaN-based high electron mobility transistors by cathodoluminescence spectroscopy

In this paper, we performed a high-resolution measurement of channel temperature rise in GaN-based high electron mobility transistors (HEMTs). Cathodoluminescence spectroscopy in the scanning electron microscope was used to probe the temperature rise with several tens of nanometers spatial resolution and accuracy better than ±8 °C. We also determined the temperature distribution and peak temperature change with the power density in active AlGaN/GaN HEMTs in the source–gate and gate–drain openings. The measured results agree reasonably well with physical 2D electrothermal simulations and Raman thermography.

Industrial–Organizational Psychologists in Business Schools: Brain Drain or Eye Opener?

We conducted a quantitative and a qualitative study to assess the extent to which industrial and organizational (I–O) psychology has moved to business schools, understand the nature of this move, and offer a balanced discussion of positive and negative consequences of this phenomenon. In quantitative Study 1, we provide evidence that I–O psychologists affiliated with business schools currently constitute a majority of editorial board members and authors of articles published inJournal of Applied PsychologyandPersonnel Psychologybut that I–O psychology, as a field, is growing. These results suggest that it is not the field of I–O psychology but some of the most active and influential I–O psychology researchers who are moving to business schools. In qualitative Study 2, we gathered perspectives from 144 SIOP Fellows and 27 SIOP presidents suggesting different views on Study 1's results ranging from very negative (i.e., “brain drain”) to very positive (i.e., “eye opener”) depending on the affiliation of the respondent. On the basis of these results, we offer 10 admittedly provocative predictions to stimulate follow-up research and serve as a catalyst for an important conversation, as well as the development of action plans, regarding the future of I–O psychology as a field.

Control ofCulex quinquefasciatusin a storm drain system in Florida using attractive toxic sugar baits

Attractive toxic sugar baits (ATSBs) were used to control mosquitoes in the storm drains of a residential area on the outskirts of St Augustine, Florida. The drainage system was newly constructed and no mosquitoes were breeding inside it. The area covered by the storm drains was divided in half; 10 drains served as control drains and 16 drains served as experimental drains. The baits, which consisted of a mixture of brown sugar, fruit juice, green dye marker and boric acid, were presented at the entrances of the treated drains and exit traps were positioned over the drain openings and the connecting tubes leading to retention ponds. Similar baits with orange dye and without toxin were presented at the entrances of control drains. A total of 220 pupae of Culex quinquefasciatus (Diptera: Culicidae) were released in each control and toxin-treated drain, and the numbers of recovered mosquitoes were examined to determine the effectiveness of ATSBs in the storm drain system. An average of 178.2 mosquitoes exited each drain in the control area; 87.0% of these had fed on the baits and were stained orange, whereas 13.0% were unstained. In the toxin-treated drains, 83.7% of hatched females and 86.6% of hatched males were controlled by the baits.

Occlusive dressings and gauze dressings did not differ for healing open wounds in surgical patients

D T Ubbink Dr D T Ubbink, Academic Medical Center, Amsterdam, The Netherlands; d.ubbink@amc.nl How do occlusive dressings compare with gauze dressings for healing open wounds in surgical patients? ###...

Density stratified environments: the double-tank method

We present an alternative method of producing density stratifications in the laboratory based on the ‘double-tank’ method proposed by Oster (Sci Am 213:70–76, 1965). We refer to Oster’s method as the ‘forced-drain’ approach, as the volume flow rates between connecting tanks are controlled by mechanical pumps. We first determine the range of density profiles that may be established with the forced-drain approach other than the linear stratification predicted by Oster. The dimensionless density stratification is expressed analytically as a function of three ratios: the volume flow rate ratio n, the ratio of the initial liquid volumes λ and the ratio of the initial densities ψ. We then propose a method which does not require pumps to control the volume flow rates but instead allows the connecting tanks to drain freely under gravity. This is referred to as the ‘free-drain’ approach. We derive an expression for the density stratification produced and compare our predictions with saline stratifications established in the laboratory using the ‘free-drain’ extension of Oster’s method. To assist in the practical application of our results we plot the region of parameter space that yield concave/convex or linear density profiles for both forced-drain and free-drain approaches. The free-drain approach allows the experimentalist to produce a broad range of density profiles by varying the initial liquid depths, cross-sectional and drain opening areas of the tanks. One advantage over the original Oster approach is that density profiles with an inflexion point can now be established.

Does temporary clamping of drains following knee arthroplasty reduce blood loss? A randomised controlled trial

In a randomised, blinded study 76 patients undergoing primary total knee arthroplasty were assigned to either immediate drain opening ( n=45) or drains opened at 2 h ( n=31). No significant differences were found between the groups for the volume of drained blood, transfusion requirements, knee motion or wound status. The authors conclude that the practice of clamping drains has no benefit in routine knee arthroplasty. However, when faced with immediate brisk blood loss, the results suggest that drains can be clamped without any excess morbidity.

Ingestion of lye

This paper reports on the case of a 13-year-old white male who committed suicide by ingestion of heavy duty drain and sewer opener. He left behind a note indicating his suicide. This teenager was grieving over the suicide of one of his friends and was under counseling by a mental health therapist at school. Results of autopsy and toxicological analyses indicated the ingestion of a highly alkaline substance that is consistent with the ingredients of the drain opener mentioned.

The Ability of two lay groups to Judge Product Warning Effectiveness

How well can lay people assess the effectiveness or “adequacy” of product warnings without assistance from expert testimony? To begin to answer this question, two studies were conducted to determine the extent to which law students and engineering students could assess the relative effectiveness of two drain opener warning label designs. In the first experiment, only 18 of the 38 engineering students (47%) correctly identified the warning label design that had, in a previous study, been shown to be significantly more effective with similar subjects who actually used the product. In addition, these subjects did not accurately predict the likelihood that their peers would read and comply with the precautions. In the second experiment, only 14 of the 42 law students (33%) correctly identified the more effective of two label designs. This research contradicts several legal authors who postulate that juries are capable of determining the effectiveness of a warning unaided by well-founded expert testimony. More specifically, these studies do not support the assertion that the “knowledge of ordinary people” is sufficient to 1) distinguish between warnings that differ in their behavioral effectiveness and 2) accurately predict the likelihood that people such as themselves will read and heed safety instructions when using a product.

Effect of location and presentation format on attention to and compliance with product warnings and instructions

Abstract Eighty subjects used a drain opener with one of four labels in an experiment to determine the effect of safety information location relative to usage instructions and the effect of presentation format of usage instructions (prose vs. numbered list) on the attention to and compliance with on-product warnings and instructions. Contrary to current/recommended practice, substantially more subjects read and complied with warnings that appeared in the “Directions for Use” rather than the “Precautions” section. On average, moving a statement from the “Precautions” into the “Directions” increased the reading rate from 37% to 89% and the compliance rate from 48% to 83%. The presentation format did not affect overall label effectiveness. This research is particularly applicable to labeling guidelines and regulations calling for precautions to be separated from usage instructions. This research also illustrates the value of a user-oriented label design approach facilitated by a technique developed for analyzing existing/prototype labels.

Thin-section study of soil materials near perforations in corrugated subsurface drains

Laboratory experiments with drainage simulators were performed using a sample of weakly structured sandy loam and four different types of corrugated subsurface drains. Following the experiments, thin sections were made to investigate the soil arrangement near drain perforations. Results show that soil aggregates can form bridges that will stop the flow of sediment into the drain. Bridges formed of individual soil particles were observed at drain openings. For the weakly structured sandy loam studied, the soil material near the drain is not homogeneous. Preferential channels leading to drain openings were observed near 16 of 38 perforations.