Symptoms Mulberry roots are infected by root-knot nematodes and cause root tissue to overgrow, form tumors of varying sizes, small like bean, large as eggs, and irregular spherical appearance. At the beginning of nodule formation, it was yellow-white, with a smooth surface. It was firm, and the nodule was dissected. The translucent milky white granular material, namely the female nematode, was visible to the naked eye, and the nodule turned brown to black and rotted. The disease causes the plants to appear as a deficiency or lack of water in the aboveground parts of the plant. The growth of the diseased plant is slow, dwarf, the branches are small and slender, the leaves are small and thin, the parietal lobe is difficult to stretch, the serious leaf color turns yellow, and the leaf margin folds. Or dry off, branches dry and dead. Both the north and south of China's sangzhi area have occurred. General mulberry seedlings will begin to develop after 2-3 years of cultivation. Production will be reduced significantly, and will gradually die in 4-5 years. After 2-3 years of planting in severe areas, growth will decline and even die. Transmission routes and conditions Peanut root-knot nematodes, Northern root-knot nematodes are 3-4 generations old, and M. incognita is 7 generations old. Meloidogyne nematophila adults, larvae and eggs overwinter in diseased roots or diseased soils, and the eggs began to hatch at a temperature of 11.3°C in late spring. The larvae began to invade mulberry roots at 2nd instar, and gradually formed nodules. Once mulberry trees are infected with root-knot nematodes, various nematodes often overlap from generation to generation. Suitable for the activity temperature range of 11.3-34 °C, the infection temperature of 20 to 25 °C, suitable soil moisture of about 70%. The rainy season is suitable for the warm season. The production of hillside, hilly and sandy soils is heavy. Prevention methods (1) Breed disease-free seedlings and implement rotation. (2) Deal with the mulberry seedlings infected with seedlings of the southern root-knot nematode. Before planting, seedlings with a growth period of more than two months should be soaked in warm water of 48-52°C for 20-30 minutes to effectively kill intra-tumor nematodes. (3) Soil disinfection Every 1,000m2 of soil is evacuated with 225kg of lime uniformly after sowed in the ditch. It is also possible to use ammonia water 150-200kg. After the trench is opened, the cover soil is compacted and sowed every 10 days.
Ventilator block diagram Medical Positive Pressure Breathing Machine Positive Pressure Breathing Machine,Continuous Positive Pressure Ventilation,Intermittent Positive Pressure Ventilation,Intermittent Positive Pressure Breathing Machine Guangzhou Zhongzhinan Supply Chain Co.,Ltd. , https://www.gzzhongzhinan.com
Pathogen Meloidogyne arenaria (Neal.) Chitwood. Peanut root knot nematodes, M. hapla Chitwood called northern root knot nematodes, M. incognita (Kofoid and White) Chitwood called southern root knot nematodes, M. Mali Ito said that apple root knot nematode, M. javanica (Treub) Chitwood called Java root knot nematode. Peanut root knot nematodes are mainly found in Jiangsu, Zhejiang, or north of China, and southern root-knot nematodes are mainly found in the Guangdong silkworm area. After the nematode invades the mulberry tree, it continuously absorbs nutrients from the roots. At the same time, the nematode secretes saliva and contains a secretion that stimulates the increased deformation of the root cells, producing giant cells that cause the root tissue to overgrow and form tumors of varying sizes. Things, namely root nodules. Peanut root knot nematode morphology see this book peanut root knot nematode disease.
One. Main mechanical ventilation modes
(1) Intermittent Positive Pressure Ventilation (IPPV): positive pressure in the inspiratory phase and zero pressure in the expiratory phase. 1. Working principle: The ventilator generates positive pressure in the inspiratory phase and presses the gas into the lungs. After the pressure rises to a certain level or the inhaled volume reaches a certain level, the ventilator stops supplying air, the exhalation valve opens, and the patient's thorax Passive collapse of the lungs and exhalation. 2. Clinical application: Various patients with respiratory failure mainly based on ventilation function, such as COPD.
(2) Intermittent positive and negative pressure ventilation (IPNPV): the inspiratory phase is positive pressure and the expiratory phase is negative pressure. 1. How it works: The ventilator works both in the inspiratory and exhaled phases. 2. Clinical application: Expiratory negative pressure can cause alveolar collapse and cause iatrogenic atelectasis.
(3) Continuous positive pressure airway ventilation (CPAP): Refers to the patient's spontaneous breathing and artificial positive airway pressure during the entire respiratory cycle. 1. Working principle: Inspiratory phase gives continuous positive pressure air flow, and exhalation phase also gives a certain resistance, so that the airway pressure of inhalation and exhalation phases are higher than atmospheric pressure. 2. Advantages: The continuous positive pressure airflow during inhalation is greater than the inspiratory airflow, which saves the patient's inhalation effort, increases FRC, and prevents the collapse of the airway and alveoli. Can be used for exercise before going offline. 3. Disadvantages: great interference to circulation, large pressure injury of lung tissue.
(4) Intermittent command ventilation and synchronized intermittent command ventilation (IMV / SIMV) IMV: There is no synchronization device, the ventilator air supply does not require the patient's spontaneous breathing trigger, and the time of each air supply in the breathing cycle is not constant. 2. SIMV: There is a synchronization device. The ventilator gives the patient a commanded breath according to the pre-designed breathing parameters every minute. The patient can breathe spontaneously without being affected by the ventilator. 3. Advantages: It exerts its ability to regulate breathing while offline; it has less influence on circulation and lungs than IPPV; it reduces the use of shock medicine to a certain extent. 4. Application: It is generally considered to be used when off-line. When R <5 times / min, it still maintains a good oxygenation state. You can consider off-line. Generally, PSV is added to avoid respiratory muscle fatigue.
(5) Mandatory ventilation per minute (MMV) When spontaneous breathing> preset minute ventilation, the ventilator does not command ventilation, but only provides a continuous positive pressure. 2. When spontaneous breathing is less than the preset minute ventilation volume, the ventilator performs command ventilation to increase the minute ventilation volume to reach the preset level.
(6) Pressure Support Ventilation (PSV) Definition: Under the prerequisite of spontaneous breathing, each inhalation receives a certain level of pressure support, increasing the patient's inhalation depth and inhalation volume. 2. How it works: The inspiratory pressure begins with the patient's inspiratory action, and ends when the inspiratory flow rate decreases to a certain level or the patient attempts to exhale hard. Compared with IPPV, the pressure it supports is constant, and it is adjusted by the feedback of the inspiratory flow rate. Compared with SIMV, it can get pressure support for each inhalation, but the level of support can be set according to different needs. 3. Application: SIMV + PSV: used for preparation before off-line, can reduce breathing work and oxygen consumption Indications: Exercise the ventilator; prepare before going offline; the ventilator is weak due to various reasons; severe flail chest causes abnormal breathing. 5. Note: Generally not used alone, it will produce insufficient or excessive ventilation.
(7) Volume Supported Ventilation (VSV): Each breath is triggered by the patient's spontaneous breathing. The patient can also breathe without any support and can reach the expected TV and MV levels. The ventilator will allow the patient to be truly autonomous Breathing also applies to preparations before going offline.
(8) Capacity control of pressure regulation
(IX) Biphasic or bilevel positive pressure ventilation How it works: P1 is equivalent to inspiratory pressure, P2 is equivalent to breathing pressure, T1 is equivalent to inspiratory time, and T2 is equivalent to exhalation time. 2. Clinical application: (1) When P1 = inspiratory pressure, T1 = inspiratory time, P2 = 0 or PEEP, T2 = expiratory time, which is equivalent to IPPV. (2) When P1 = PEEP, T1 = infinity, P2 = 0, T2 = O, which is equivalent to CPAP. (3) When P1 = inspiratory pressure, T1 = inspiratory time, P2-0 or PEEP, T2 = desired controlled inhalation cycle, equivalent to SIMV.