Surgical site infection after gastrointestinal surgery in high-income, middle-income, and low-income countries: a prospective, international, multicentre cohort study

Background: Surgical site infection (SSI) is one of the most common infections associated with health care, but its importance as a global health priority is not fully understood. We quantified the burden of SSI after gastrointestinal surgery in countries in all parts of the world. Methods: This international, prospective, multicentre cohort study included consecutive patients undergoing elective or emergency gastrointestinal resection within 2-week time periods at any health-care facility in any country. Countries with participating centres were stratified into high-income, middle-income, and low-income groups according to the UN's Human Development Index (HDI). Data variables from the GlobalSurg 1 study and other studies that have been found to affect the likelihood of SSI were entered into risk adjustment models. The primary outcome measure was the 30-day SSI incidence (defined by US Centers for Disease Control and Prevention criteria for superficial and deep incisional SSI). Relationships with explanatory variables were examined using Bayesian multilevel logistic regression models. This trial is registered with ClinicalTrials.gov, number NCT02662231. Findings: Between Jan 4, 2016, and July 31, 2016, 13 265 records were submitted for analysis. 12 539 patients from 343 hospitals in 66 countries were included. 7339 (58·5%) patient were from high-HDI countries (193 hospitals in 30 countries), 3918 (31·2%) patients were from middle-HDI countries (82 hospitals in 18 countries), and 1282 (10·2%) patients were from low-HDI countries (68 hospitals in 18 countries). In total, 1538 (12·3%) patients had SSI within 30 days of surgery. The incidence of SSI varied between countries with high (691 [9·4%] of 7339 patients), middle (549 [14·0%] of 3918 patients), and low (298 [23·2%] of 1282) HDI (p < 0·001). The highest SSI incidence in each HDI group was after dirty surgery (102 [17·8%] of 574 patients in high-HDI countries; 74 [31·4%] of 236 patients in middle-HDI countries; 72 [39·8%] of 181 patients in low-HDI countries). Following risk factor adjustment, patients in low-HDI countries were at greatest risk of SSI (adjusted odds ratio 1·60, 95% credible interval 1·05–2·37; p=0·030). 132 (21·6%) of 610 patients with an SSI and a microbiology culture result had an infection that was resistant to the prophylactic antibiotic used. Resistant infections were detected in 49 (16·6%) of 295 patients in high-HDI countries, in 37 (19·8%) of 187 patients in middle-HDI countries, and in 46 (35·9%) of 128 patients in low-HDI countries (p < 0·001). Interpretation: Countries with a low HDI carry a disproportionately greater burden of SSI than countries with a middle or high HDI and might have higher rates of antibiotic resistance. In view of WHO recommendations on SSI prevention that highlight the absence of high-quality interventional research, urgent, pragmatic, randomised trials based in LMICs are needed to assess measures aiming to reduce this preventable complication

Kuliamo kukurūzų srauto judėjimas tarpe tarp būgno ir pobūgnio

Experimental results shown, that with the increase the momentum of inertia of the threshing cylinder the rotation speed was less shifting by variable load of threshing unit. The threshing crescent of the laboratory threshing unit was filmed using high speed camera Photron Fastcam 1024 PCI (2000 frames per second) through a transparent side panel. The cylinder peripheral speed was 14.7 ms-1. When threshed cobs were moved in threshing crescent perpendicular whit the cylinder shaft the average speed of cobs was 2.93 ms-1, and when parallel – 4.85 ms-1. It has been noted, from observation of high speed movie film of the threshing of corn, that the kernels once threshed encounter difficulty in passing through the concave. That is, the damage occurred whilst the kernels were mowing within the threshing crescent prior to passing the concave or from the threshing crescent. It is desirable to remove the kernels from the threshing crescent as soon as possible after threshingVytauto Didžiojo universitetasŽemės ūkio akademij

Kuliamo kukurūzų srauto judėjimas tarpe tarp būgno ir pobūgnio

Experimental results shown, that with the increase the momentum of inertia of the threshing cylinder the rotation speed was less shifting by variable load of threshing unit. The threshing crescent of the laboratory threshing unit was filmed using high speed camera Photron Fastcam 1024 PCI (2000 frames per second) through a transparent side panel. The cylinder peripheral speed was 14.7 ms-1. When threshed cobs were moved in threshing crescent perpendicular whit the cylinder shaft the average speed of cobs was 2.93 ms-1, and when parallel – 4.85 ms-1. It has been noted, from observation of high speed movie film of the threshing of corn, that the kernels once threshed encounter difficulty in passing through the concave. That is, the damage occurred whilst the kernels were mowing within the threshing crescent prior to passing the concave or from the threshing crescent. It is desirable to remove the kernels from the threshing crescent as soon as possible after threshingVytauto Didžiojo universitetasŽemės ūkio akademij

Būgno inercijos momento įtaka kūlimo ir grūdų separacijos procesams

Combines perform four operations: cutting, threshing, separating, and cleaning. Acceptable grain losses from each operation limit the throughput capacity and performance of a combine. The objective of this research was to investigate the influence of inertia momentum of threshing cylinder on grain separation through concave. Grain damage is closely related to cylinder speed, cylinder clearance, and grain moisture content. Grain damage increased from 3.10+0.43% to 4.91+0.34% as the momentum of inertia of the ±sreshing cylinder was increased from 8.34 kg-m2 to 15.73 kg-m2. However as the momentum of inertia was greater the grain separation through concave increased about 7.7%, i.e. less of threshed grains thrown from the threshing unit on to straw walkersVytauto Didžiojo universitetasŽemės ūkio akademij

Influence of momentum inertia of threshing cylinder on power consumption

The combine is a machine used to harvest, thresh, and clean grains from a variety of crop and field conditions. The main purpose of combine harvesting is to recover grain with a minimum grain loss, grain damage, and power requirement. The objective of this research was to investigate the influence of inertia momentum of threshing cylinder on power consumption. The power required by the threshing drum can be expressed as the summation of power to operate a machine with no material and power to process material. The power required to process material will vary with many variables: volume flow rate of material, concave clearance and length, cylinder speed, number of bars on the cylinder etc. Experimental results shown, that the rotation frequency and momentum of inertia of the threshing cylinder influence to power consumption for its rotation. With the increase the momentum of inertia of the threshing cylinder from I = 8.34 kgm2 to I = 15.73 kgm2, the power requirement for idle running of threshing cylinder increase about 0.1 kW. When the feederate is changes from 4 kgs-1 to 14 kgs-1, the power consumption for threshing of corn cobs increases from 2.5 kW to 7.7 kWVytauto Didžiojo universitetasŽemės ūkio akademij

Grain separation from pith under quasi-static radial compression ear

Corn yield in hectare can be from 50 to 70 tons of green mass or from 6 to 10 tons of grain. Corn for grain can harvested by several technologies, when the grain in ears is in physiological stage of maturity. The investigations of corn ears threshing process is related to the interaction between rasp bars and com ears. The force of grain connections to the ear was measured with the devices „Instron 4301" and attached writer „YEW 3033 X-Y" and with "FM- 1000". Theoretical equations were developed for calculating the reaction force of the grain to the ear pith arc of corn ear under its quasi-static radial compression. The empirical coefficients of friction, grain weight and measurements were used in theoretical equations. It was established that when the drum rasp bar p grain of ear then the adjacent grains are primarily separated from the pith. Grain separation depends on the acting force of rasp barsVytauto Didžiojo universitetasŽemės ūkio akademij

A theoretical investigation of concave bars for corn ears threshing

The most important constructive parameters by corn ears threshing are design, height, number of concave crossbars and their position in respect of threshing cylinder. There is a lack of research evaluating an impact of concave crossbars design on corn grains detaching from cob, grains damage and separation through the concave. A major hypothesis of the study is that a concave crossbars form has an impact on corn ear threshing efficiency. It is known that the corn ear threshing process depends on effectiveness of first interaction between the cylinder rasp bar and corn ear in threshing apparatus. The theoretical study has been based on investigations of three different forms of concave crossbars: rectangular, rounded and oblique. The force of ear gravity (G); the reaction force (N1) of concave bar on corn ear; the reaction force (N22) of ear cob reaction on grain which is in contact with concave bar; the reaction force (N12) of subsequent grain on grain which is in contact with concave bar; the reaction forces (N2 and N3) of longitudinal rod reaction on ear (based on touch of ear with two grains on longitudinal rod of concave) have been evaluated. Acting frictional forces have been expressed as products of reaction forces and coefficients of friction. Five equilibrium equations with five unknown have been composed. Acting reaction, frictional and gravity forces have been designed to x and y coordinates axes for this reason. Furthermore, moments of acting forces around the chosen points have been fixed. Using the Maple software, numerical values of unknown forces have been found. It has been determined that numerical values of the reaction forces N1 and N12 were the biggest at oblique design of concave bars. Accordingly, it seems possible that then threshing process at the first corn ear contact with the rasp bar will be more effectiveVytauto Didžiojo universitetasŽemės ūkio akademij

The influence of concave design on grain separation and damage

Experimental concave has a positive effect on grain damage during threshing (reduces per-centage of damaged grain by 0.5 percentage units) and grain separation through the concave (in-creases grain separation intensity through concave). Further research is necessary to optimize sur-face form of the cross bars of concave and gaps between themVytauto Didžiojo universitetasŽemės ūkio akademij

The influence of concave crossbar on corn ear in effect of rasp bars impact

The study examines interaction between the corn ear, rasp bar and concave crossbar. Corn ears linear velocity was examined in seven parts. Grain separation also was monitored. Experiments was made in five positions of concave crossbar (0, 3, 6, 9, 12 mm), rasp bar was moving at speed of 14 m∙s-1. Laboratory studies showed that increasing concave crossbar height increases grain separation from pith. The biggest separation (examining the corn ear hits the 12 mm high concave crossbar) is equal to 79.70 ± 3.28%. Studies showed that corn ear pith disintegrates after impact of corn ear at 12 mm position concave crossbar, so it should not be used. Examination of other cases did not show much difference between the different tests. The influence of tested three concave crossbar heights (3, 6, 9 mm) on corn ears at the monitored speed characteristics is minimalVytauto Didžiojo universitetasŽemės ūkio akademij

The influence of design of concave rasp bars on grain separation and damage

The experimental threshing unit was comprised of the corn ears belt-feeder with the length of 10 m and width of 0.8 m, and the tangential threshing cylinder with 10 rasp bars with the diameter of 0.8 m and width of 0.8 m, which was enveloped by the grate-bar type concave at the angle of 130º. The studies have been designed and manufactured five different forms of concave bars, which mounted in the variable radius concave. Rasp bars of concave have a positive effect on grain damage during threshing, grain separa-tion through the concave (increases grain separation intensity through concave) and threshing loss. Studies reasonable that the corn ears threshing rational to use L = 20 mm width and the surfa-ce angle α = 23° rasp bars of variable radius concave. Then threshing grain losses are minimal (0.03 ± 0.02%), while the injured cereal grain damage does not exceed 4%Vytauto Didžiojo universitetasŽemės ūkio akademij