Optimizing feeding regimen of replacement gilts to improve their reproductive performance and retention rate of their first 2 parities

The effects of age,body weight(BW),and backfat thickness(BF)of replacement gilts at first estrus and first mating on their subsequent reproductive performance and retention of their first 2 parities as sows was evaluated.A total of 3,025 Danish replacement gilts were categorized by farm(allocated to 4 farms),cross combination,age,BW and BF at first estrus and first mating,estrous cycle number at first mating,and flush feeding before first mating.The result shows that all the factors mentioned above were significantly associated with reproductive performance and retention rates of the first 2 parities.Farm 3 had more piglets born alive per litter(BA)(P<0.05).Farms 3 and 4 had more healthy piglets per litter(HP)(P<0.05).Farm 4 had the most piglets weaned per litter(PW)(P<0.05).Landrace×Landrace×Yorkshire(L×L×Y)replacement gilts had the most total piglets born per litter(TB),BA,HP,PW and a higher retention rate of the 2 parities than Landrace×Yorkshire(L×Y)replacement gilts(P<0.05).In addition,flush feeding before first mating had the most TB,BA,HP,PW,and a higher retention rate of the 2 parities than no flush feeding(P<0.05).Because the effects of replacement gilts rearing parameters on reproductive performance traits differed,we used 100 replacement gilts as a unit and the total number of weaned piglets from the first 2 parities as a new index.Replacement gilts undergoing their first estrus between 180 and 210 d of age at 115 to 124.9 kg BW and 14 to 15 mm BF had significantly higher reproductive indexes for their first 2 parities per 100 replacement gilts.Replacement gilts that mated between 210 and 230 d of age at 140 to 149.9 kg BW and 15 to 16 mm BF had optimal reproductive indexes.These results provide a new insight into the complex relationships among these reproductive performance traits and may help guide successful management of replacement gilts as a pivotal starting point for future fertility and longevity of rearing herds.

Elaboration of Ceramic Pot Filter from Kaolinite (Cameroon Clay) for the Elimination of Suspended Particles from Domestic Drinking Water

The objective of this work was to elaborate ceramic water filters from Kaolinite (Cameroon) clay for the elimination of suspended particles from domestic drinking water. In Sub-Sahara Africa and in Cameroon in particular health issues have been linked to the consummation of domestic tap water of high turbidity values both in the rural and urban areas. In order to remedy these problems, ceramic water pot filters have been elaborated in a pilot scale unit with aim of putting in place a unit production. The chemical composition, the thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) analyses of the raw materials (clay and rice husks) was determined. The crystal phases and scanning electron microscope of Wack clay was also determined. The ceramic pot filter membranes were fabricated from the formulations 70/20/10 of clay/porogen/chamotte respectively with the particle size of the raw material less than or equal to 500 μm. The formulated ceramic pot filters were then sintered at 900˚C in a furnace. These ceramic pot filters were characterized by determining their porosity, withdrawal percentages, water permeability, mechanical and chemical resistance. The study of the efficiency consisted in evaluating the retention rate and permeate flux with respect to time (days) with synthetic water suspensions of turbidity 100 NTU and particle size of 2 μm. The ceramic pot filters were made aiming at studying the efficiency after physical defouling of filters. Physical defouling consisted in brushing the inner surface of the ceramic pot filters with water and drying them at ambient temperature after being used for 11 days and reusing them under the same initial conditions. The produced ceramic pot filter had a volume of 4 L, an average porosity of 36.15%, shrinkage in mass or withdrawal percentage of 18.23%, a water permeability of 59.6 × 103 L∙h−2∙m−2, mechanical resistance of 6.8 MPa and corrosion resistance of 1.6% in acidic medium and 0.8% in alkaline medium. The evaluation of the retention efficiency reveals that the retention rate of 99.9% was obtained from the 9th day of filtration reducing the turbidity value from 100 NTU to less than 0.1 NTU. From the filtration test carried out during the 11 consecutive days, the flow rate varied between 1.46 L∙h−1 to 2.63 L∙h−1. Similar results of retention and flow rate were obtained after physical defouling of the ceramic pot filter membranes and re-using for 11 consecutive days, showing the efficiency of the ceramic pot filter membranes in eliminating suspended particles from drinking water. Cost evaluation for the production unit reveals a total cost of production for 50 ceramic pot filters of 1593.6 USD consisting of fixed assets and variable assets. An estimated selling price of 3.3 USD was obtained which is affordable for both the urban and rural population in Cameroon and in sub-Saharan Africa.

Elaboration of Ceramic Pot Filter from Kaolinite (Cameroon Clay) for the Elimination of Suspended Particles from Domestic Drinking Water

The objective of this work was to elaborate ceramic water filters from Kaolinite (Cameroon) clay for the elimination of suspended particles from domestic drinking water. In Sub-Sahara Africa and in Cameroon in particular health issues have been linked to the consummation of domestic tap water of high turbidity values both in the rural and urban areas. In order to remedy these problems, ceramic water pot filters have been elaborated in a pilot scale unit with aim of putting in place a unit production. The chemical composition, the thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) analyses of the raw materials (clay and rice husks) was determined. The crystal phases and scanning electron microscope of Wack clay was also determined. The ceramic pot filter membranes were fabricated from the formulations 70/20/10 of clay/porogen/chamotte respectively with the particle size of the raw material less than or equal to 500 μm. The formulated ceramic pot filters were then sintered at 900˚C in a furnace. These ceramic pot filters were characterized by determining their porosity, withdrawal percentages, water permeability, mechanical and chemical resistance. The study of the efficiency consisted in evaluating the retention rate and permeate flux with respect to time (days) with synthetic water suspensions of turbidity 100 NTU and particle size of 2 μm. The ceramic pot filters were made aiming at studying the efficiency after physical defouling of filters. Physical defouling consisted in brushing the inner surface of the ceramic pot filters with water and drying them at ambient temperature after being used for 11 days and reusing them under the same initial conditions. The produced ceramic pot filter had a volume of 4 L, an average porosity of 36.15%, shrinkage in mass or withdrawal percentage of 18.23%, a water permeability of 59.6 × 103 L∙h−2∙m−2, mechanical resistance of 6.8 MPa and corrosion resistance of 1.6% in acidic medium and 0.8% in alkaline medium. The evaluation of the retention efficiency reveals that the retention rate of 99.9% was obtained from the 9th day of filtration reducing the turbidity value from 100 NTU to less than 0.1 NTU. From the filtration test carried out during the 11 consecutive days, the flow rate varied between 1.46 L∙h−1 to 2.63 L∙h−1. Similar results of retention and flow rate were obtained after physical defouling of the ceramic pot filter membranes and re-using for 11 consecutive days, showing the efficiency of the ceramic pot filter membranes in eliminating suspended particles from drinking water. Cost evaluation for the production unit reveals a total cost of production for 50 ceramic pot filters of 1593.6 USD consisting of fixed assets and variable assets. An estimated selling price of 3.3 USD was obtained which is affordable for both the urban and rural population in Cameroon and in sub-Saharan Africa.

Multi-Location Investigation of Optimum Planting Density and Boll Distribution of High-Yielding Cotton (G.hirsutum L.) in Hubei Province,China

Cotton yield per unit ground area has stagnated for a dozen years in Hubei Province, China, although a series of new high- yielding varieties have been commercialized. A multi-location investigation was carried out in 2008 and 2009 in 13 counties to determine if increased planting population density （PPD） would break the stagnant yield. The results showed that significant differences among the fields existed in theoretical yield, PPD, and bolls per square meter （BPM）. The lowest yield of 1 641.1 kg ha-I was resulted from the lowest PPD of 1.7 plants m-2 and the lowest BPM of 71.8 bolls m-2, while the highest yield of 2 779.7 kg ha-~ was resulted from the highest PPD of 2.5 plants m-2, and the highest BPM of 129.4 bolls m-z. Plant mapping revealed that boll retention rate （BRR） was maintained over 30 or 40% for the first 17-18 fruiting branches （FBs） and decreased dramatically thereafter, rotten boll rate （RBR） decreased, but open boll rate （OBR） rose first and dropped later with rising FB from the bottom to the top. But BRR, RBR, and OBR were all dropped with the fruiting positions （FPs） extending outwards. The optimum range of plant density would be 2-3 plants m-2 and the proper individual plant structure would be 16-19 FBs with 5-7 FPs for cotton production in Hubei Province.

Insights from coastline survey in Shandong Province,China

The coastline,as the boundary between land and sea,is shaped by both natural factors and human activities.Based on concrete practice from coastline survey in Shandong Province,this study discusses the applicability of the local standard Specification for Coastline Survey(DB 37/T 3588-2019).The coastline classification system takes into account the coastline characteristics and marine management requirements in Shandong Province.To be specific,the coastline with natural beach morphology and ecological function is involved,and its delimitation method is innovated.The coastline delimitation of sandy beach,aquaculture pond and salt pan follows the trace line of the mean high water springs(MHWS),but the coastline location of sandy beach can also be at the base of cliffs or at the foot of seawalls and roads considering the dynamic changes of the beach in different seasons and the integrity of the beach topography.The delineation of estuarial coastline is to achieve the complete coastline,and should not be used for the statistics of natural coastline retention rate.At present,the review of survey results has been completed.With the promulgation of survey results next,the formulation of relevant mechanisms and policies should promptly be put on the agenda,including regular investigation and data updating,natural coastline assessment,natural coastline requisition-compensation,and coastline protection planning.

Long-term Effectiveness of Antiepileptic Drug Monotherapy in Partial Epileptic Patients： A 7-year Study in an Epilepsy Center in China

Background： It is important to choose an appropriate antiepileptic drug （AED） to manage partial epilepsy. Traditional AEDs, such as carbamazepine （CBZ） and valproate （VPA）, have been proven to have good therapeutic effects. However, in recent years, a variety of new AEDs have increasingly been used as first-line treatments for partial epilepsy. As the studies regarding the effectiveness of new drugs and comparisons between new AEDs and traditional AEDs are few, it is determined that these are areas in need of further research. Accordingly, this study investigated the long-term effectiveness of six AEDs used as monotherapy in patients with partial epilepsy. Methods： This is a retrospective, long-term observational study. Patients with partial epilepsy who received monotherapy with one of six AEDs, namely, CBZ, VPA, topiramate （TPM）, oxcarbazepine （OXC）, lamotrigine （LTG）, or levetiracetam （LEV）, were identified and followed up from May 2007 to October 2014, and time to first seizure after treatment, 12-month remission rate, retention rate, reasons for treatment discontinuation, and adverse effects were evaluated. Results： A total of 789 patients were enrolled. The median time of follow-up was 56.95 months. CBZ exhibited the best time to first seizure, with a median time to first seizure of 36.06 months （95% confidential interval： 30.64~4.07）. CBZ exhibited the highest 12-month remission rate （85.55%）, which was significantly higher than those of TPM （69.38%, P = 0.006）, LTG （70.79%, P= 0.001）, LEV （72.54%, P = 0.005）, and VPA （73.33%, P = 0.002）. CBZ, OXC, and LEV had the best retention rate, followed by LTG, TPM, and VPA. Overall, adverse effects occurred in 45.87% of patients, and the most common adverse effects were memory problems （8.09%）, rashes （7.76%）, abnormal hepatic function （6.24%）, and drowsiness （6.24%）. Conclusion： This study demonstrated that CBZ, OXC, and LEV are relatively effective in managing tbcal epilepsy as measured by time to first seizure, 12-month remission rate, and retention rate.

Effects of operating conditions on membrane charge property and nanofiltration

The effects of the operating pressure,crossflow velocity,feed concentration,and temperature on the streaming and Zeta potential of the membranes were studied.The permeateflux and the retention rate under different nanofiltration operating conditions were also investigated.The results show that the higher pressure,feed concentration,temperature,and lower crossflow velocity lead to the higher absolute value of streaming and Zeta potential.The permeateflux of the nanofiltration decreases with the feed concentration and increases with not only the pressure but also the crossflow velocity and temperature.The higher the pressure and the crossflow velocity,the higher the retention rate.The lower feed concentration and higher temperature leads to lower retention rate.The effects of the operating conditions on the permeateflux and the retention rate were explained by the variation of the membrane charge property.

Experimental study on spraying performance of biological pesticides in aerial rotary cage nozzle

Aviation spraying is one of the most important methods for the treatment of forestry pests and diseases,which has a high operation efficiency and effectiveness.The combination of aviation spray and biological pesticides to reduce the impact of pesticide spray on environment has become an important development in the direction of agricultural aviation.In order to explore the effects of aviation spray parameters on particle size distribution and activity retention of biological pesticide droplets,a system of droplets size test and an activity retention rate test system of biological pesticides were constructed.The related experiments were conducted by changing the structural parameters of the rotary cage nozzle(the diameter of nozzle)and the technical parameters of the operation(rotary speed and flow rate).The results showed that the average relative width S of the droplets of the rotary cage nozzle was close to 1,and the droplet distribution was uniform.The influence factors on the particle size distribution of biological pesticide droplets were rotary speed,nozzle diameter,medium and flow rate in descending order.The rotary speed,nozzle diameter,and medium had a significant influence on droplet size distribution.The average activity retention rate of Bacillus thuringiensis was 88.83%,and the germination rate of Beauveria bassiana was 89.80%.The rotary speed had a significant effect on the activity retention rate of bacterial and fungal biological pesticides,and it was negatively correlated.The rotary speed was between 3000-5000 r/min,and the activity retention rate was higher.The research results can provide guidance for spraying biological pesticides in aerial plant protection operations with rotary cage nozzle.