28-GBd 32QAM FMF Transmission With Low Complexity Phase Estimators and Single DPLL

van Uden, Roy G. H.,Okonkwo, Chigo M.,Haoshuo Chen,de Waardt, Hugo,Koonen, Antonius M. J. IEEE 2014 IEEE photonics technology letters Vol.26 No.8

<P>As spatial division multiplexed transmission systems employing few mode fibers (FMFs) rely heavily on digital signal processing (DSP), the impact of computational complexity should be considered. A key DSP process block is the carrier phase estimation (CPE), which consists of a phase estimator and digital phase locked loop (DPLL) per output. In this letter, a low complexity phase estimator is proposed, and the common-mode laser frequency offset is exploited to reduce the number of DPLLs. The combination of a low complexity CPE and single DPLL is experimentally demonstrated for a 28 GBd six-channel transmission over a 41.7-km FMF, carrying up to 32 quadrature amplitude modulation. Thereby, the nonlinear tolerances for the proposed CPE scheme are shown to perform similarly as the more computationally complex conventional CPE scheme.</P>

Current strategies for treatment of intervertebral disc degeneration: substitution and regeneration possibilities

Sebastião van Uden,Joana Silva-Correia,Joaquim Miguel Oliveira,Rui Luís Reis 한국생체재료학회 2017 생체재료학회지 Vol.21 No.4

Background: Intervertebral disc degeneration has an annual worldwide socioeconomic impact masked as low back pain of over 70 billion euros. This disease has a high prevalence over the working age class, which raises the socioeconomic impact over the years. Acute physical trauma or prolonged intervertebral disc mistreatment triggers a biochemical negative tendency of catabolic-anabolic balance that progress to a chronic degeneration disease. Current biomedical treatments are not only ineffective in the long-run, but can also cause degeneration to spread to adjacent intervertebral discs. Regenerative strategies are desperately needed in the clinics, such as: minimal invasive nucleus pulposus or annulus fibrosus treatments, total disc replacement, and cartilaginous endplates decalcification. Main body: Herein, it is reviewed the state-of-the-art of intervertebral disc regeneration strategies from the perspective of cells, scaffolds, or constructs, including both popular and unique tissue engineering approaches. The premises for cell type and origin selection or even absence of cells is being explored. Choice of several raw materials and scaffold fabrication methods are evaluated. Extensive studies have been developed for fully regeneration of the annulus fibrosus and nucleus pulposus, together or separately, with a long set of different rationales already reported. Recent works show promising biomaterials and processing methods applied to intervertebral disc substitutive or regenerative strategies. Facing the abundance of studies presented in the literature aiming intervertebral disc regeneration it is interesting to observe how cartilaginous endplates have been extensively neglected, being this a major source of nutrients and water supply for the whole disc. Conclusion: Several innovative avenues for tackling intervertebral disc degeneration are being reported – from acellular to cellular approaches, but the cartilaginous endplates regeneration strategies remain unaddressed. Interestingly, patientspecific approaches show great promise in respecting patient anatomy and thus allow quicker translation to the clinics in the near future.

Effect of Work and Urea-Molasses Cake Supplementation on Live Weight and Milk Yield of Murrah Buffalo Cows

Van Thu, Nguyen,Uden, Peter Asian Australasian Association of Animal Productio 2000 Animal Bioscience Vol.13 No.9

Two experiments were carried out to investigate the effect of Murrah buffalo cows pulling sledges under field conditions on milk production and milk composition. In Exp. 1, 24 buffaloes in the fourth month of lactation were used. They were allotted to four treatments according to a $2{\times}2$ factorial arrangement: work or no work, and with or without urea-molasses cake supplementation (700 g/animal/day). Feeds consisted of 20 kg fresh elephant grass (18% DM), 2 kg rice bran per day and rice straw ad lib. The animals worked in pairs three hours per day (work done: $3464{\pm}786kJ/d$) five days a week for three months. Three teams worked in the morning and the others worked in the afternoon in the same day. The following day the working times were switched. In Exp. 2, 16 lactating Murrah buffalo cows in the sixth month of lactation were allotted to two groups (work and no work). They were fed with fresh ruzi grass (Brachiaria ruziziensis) ad lib. supplemented with 2 kg rice bran and 700 g urea-molasses cake. The working regime was similar to that of the first experiment (work done: $3753{\pm}879kJ/d$) and they worked for two months. In the first experiment, there was a small but significant drop (p<0.05) in milk yield from 3.5 to 3.0 kg/day due to work, but there was no supplementation effect. The working buffaloes lost 5.2 kg whereas the non-working animals gained 9.7 kg during the three months (p<0.05). Supplementation increased live weight by 9.9 kg as compared to -5.4 kg for those not supplemented (p<0.05). Milk composition was not affected by the treatments. In the second experiment, daily milk production was similar for both treatments and approximately 3 kg. No significant differences were found in milk composition or in live weight changes for working and non-working groups, respectively. It was concluded that work may cause a reduction in milk yield and a loss of live weight on a poor rice straw diet but that an appropriate supplementation can alleviate this situation.

Effect of Urea-Molasses Cake Supplementation of Swamp Buffaloes Fed Rice Straw or Grasses on Rumen Environment, Feed Degradation and Intake

Van Thu, Nguyen,Uden, Peter Asian Australasian Association of Animal Productio 2001 Animal Bioscience Vol.14 No.5

Two experiments were carried out concerning the effects of urea-molasses cake (UMC) and its separate components as supplements on rumen environment, in sacco feed degradability and intake of swamp buffaloes fed rice straw, grasses or a mixture of grasses and rice straw. Experiment 1 was a change-over design with 4 animals and 6 treatments. The buffaloes were fed rice straw ad libitum, and the experimental treatments were: no supplementation (R); 700 g of the complete urea-molasses cake (RUMC); 53.2 g urea (RU); 276 g rice bran and 52.5 coconut meal (RRC); 26.6 g salt, 26.6 g bone meal and 2.1 g trace minerals (RMi); and 25 g molasses (RMo). Experiment 2 was a Latin square design with four diets and four animals. The treatments were: rice straw ad libitum and mixed grass (RG) at 2.5 g dry matter per kg live weight (LW); RG plus 700 g urea-molasses cake (RGUMC); mixed grass ad libitum (G); and G plus 700 g cake (GUMC). In both experiments the supplements were fed once daily. In Exp. 1 although the rumen pH was significantly different (p<0.05) among diets, it varied only from 6.90 to 7.06. The ruminal ammonia was also significantly (p<0.05) different among the diets with RUMC significantly higher than R. Total bacterial and protozoal counts were significantly (p<0.05) higher for the RUMC, RU, RMo and RRC diets. Total feed and rice straw intakes were highest for RUMC (p<0.05) and lowest for the RMi and RMo diets, but in sacco degradability of four different roughages were not significantly different among diets. In Exp. 2, rumen pHs of the diets differed significantly and (p<0.01) ranged from 7.04 - 7.19. Ruminal $NH_3-N$ concentrations (mg/100 ml) were also significantly different (p<0.05), and higher for the RGUMC, G and GUMC diets. The total counts of bacteria and protozoa were significantly (p<0.05) higher for the RGUMC, G and GUMC diets. The total feed intake and roughage intake were significantly (p<0.05) higher for the RGUMC, G and GUMC diets compared to the RG diet. Correspondingly, LW changes also differed among treatments (p=0.06). It was concluded that there were significant increases in rumen $NH_3-N$ concentration, microbial populations and feed intake in the buffaloes by UMC supplementation, whereas the significant difference in in sacco DM degradation was not found by any type of supplementation. There seemed to be a need of a combination of urea, molasses, minerals and other protein nitrogen sources to enhance rice straw intake. Adding grass to the rice straw diet at 0.25% LW (DM) should also be considered to maintain buffalo rumen function and production with UMC supplementation, when rice straw is the main roughage.

Nitrogen Balance in Goats Fed Flemingia (Flemingia Macrophylla) and Jackfruit (Artocarpus Heterophyllus) Foliage Based Diets and Effect of a Daily Supplementation of Polyethylene Glycol (PEG) on Intake and Digestion

Mui, Nguyen Thi,Ledin, Inger,Uden, Peter,Binh, Dinh Van Asian Australasian Association of Animal Productio 2002 Animal Bioscience Vol.15 No.5

Diets with foliage of Flemingia (Flemingia macrophylla) or Jackfruit (Artocapus heterophyllus were fed to goats with the objective to study nitrogen (N) balance and effect of a daily supplementation of polyethylene glycol (PEG) on intake and digestion. In experiment 1, three male Alpine${\times}$Jamnapary goats with initial weights varying from 26.9 to 27.7 kg were used in a $3{\times}3$ Latin square design in the dry season. Three Alpine${\times}$Bachthao crosses, 15.3-16.7 kg, were used in the same design in the wet season. The three diets were based on chopped whole sugar cane complemented with the two green foliages, Jackfruit and Flemingia, or soybean meal (SBM). The level of dry matter (DM) offered was 4% of body weight (BW), 2.7% as foliage and 1.3% as chopped whole sugar cane. The amount of SBM offered was calculated to give the same amount of crude protein (CP) as the foliages. Each experimental period lasted 32 days (14 days for adaptation, 7 days for collection and 10 days for rest). Feed intake, apparent digestibility of DM, organic matter (OM), CP, neutral detergent fiber (NDF) and acid detergent fiber (ADF) and retained nitrogen (N) were measured by total faecal and urine collection. In experiment 2, four male goats (Alpine${\times}$Jamnapary) with initial weights from 17.1 to 23.1 kg were used in a $4{\times}4$ Latin square design. The four treatments were Jackfruit or Flemingia with or without addition of PEG, which was fed at a level of 5 g/goat and day by mixing with a small amount of rice bran. Each experimental period lasted 15 days (8 days for adaptation, 7 days for collection). Measurements were done as in experiment 1. The DM digestibility was highest (65.9-74.3%) for goats fed the SBM diet in both the dry and wet season. The DM digestibility of goats fed the Jackfruit and the Flemingia diets was similar in both the dry (58.6-59.2% respectively) and the wet season (53.9-56.1% respectively). The CP digestibility was highest (73.0-73.6%) for the SBM diet followed by the Jackfruit diet (47.0-38.5%) and was lowest (36.8-30.0%) for the Flemingia diet in both dry and wet seasons, respectively. The NDF digestibility was low for both the Jackfruit (36.4%) and Flemingia (38.0%) diets in the wet season. All diets resulted in a positive N balance. The N retention was highest (0.465-0.604 g/kg $W^{0.75}$) in the SBM diets and lowest (0.012-0.250 g/kg $W^{0.75}$) in the Flemingia diet. Addition of PEG had no effect on feed intake for any of the diets. PEG added in the Flemingia diet had a positive effect only on NDF digestibility, but the digestibility of the Jackfruit diet was significantly increased. Supplementation with PEG reduced digestibility and N retention of Flemingia, possibly because of the low tannin level, but increased digestibility and N retention for Jackfruit foliage.

The Foliage of Flemingia (Flemingia macrophylla) or Jackfruit (Artocarpus heterophyllus) as a Substitute for a Rice Bran - Soya Bean Concentrate in the Diet of Lactating Goats

Mui, Nguyen Thi,Ledin, Inger,Uden, Peter,Binh, Dinh Van Asian Australasian Association of Animal Productio 2002 Animal Bioscience Vol.15 No.1

Ninety lactating goats (Bachthao, Barbary, Beetal and Jamnapary breeds) were used in an experiment to investigate the replacement value of the tree fodders Flemingia (Flemingia macrophylla) and Jackfruit (Artocarpus heterophyllus). The foliages were used to replace the concentrate in diets based on chopped whole sugar cane (Sacharatum sp.), Para grass (Brachiaria mutica) and dried cassava root (Manihot esculanta). The concentrate was replaced by foliage of Jackfruit or Flemingia at 0%, 20%, 40%, 60% and 80% based on the crude protein (CP) content in the concentrate and foliages, respectively. Average milk yield was 1,617 g/day for goats fed Jackfruit compared to 1,532 g/day for those fed Flemingia. Increasing amounts of Flemingia foliage resulted in reduced dry matter intake and decreased milk yield but milk composition (CP, casein and fat content) was similar up to 60% replacement. Flemingia showed a poor potential as a supplement for lactating goats and replacement levels should not exceed 20% of the protein in the concentrate or 7.5% of the dry matter in the diet. With respect to the combination of milk production and net return over the control a CP replacement rate of 20% was the most promising. For Jackfruit there was similar feed intake and milk yield at a replacement level of 20% of CP in the concentrate (9.2% of DM intake) compared to the control diet. Milk yield at the level of 40% replacement (15% of the DM) in the diet was slightly reduced. Up to a level of CP replacement rate of 60% (21% DM in the diet) can be suggested for on-farm testing as a higher net return over the control was obtained on station.