| 1. |
- Forzati, Marco, et al.
(författare)
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Reduction of intra-channel four-wave mixing using the alternate-phase RZ modulation format
- 2002
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Ingår i: IEEE Photonics Technology Letters. - 1041-1135 .- 1941-0174. ; 14:9
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Tidskriftsartikel (refereegranskat)abstract
- —The authors propose a modulation format in which the phase of the signal pulses alternates, in order to reduce the intrachannel four-wave mixing. They demonstrate numerically that the performance of a 40-Gb/s transmission link can be substantially improved.
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| 2. |
- Glynn, Anders, et al.
(författare)
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Immune cell counts and risks of respiratory infections among infants exposed pre- and postnatally to organochlorine compounds : a prospective study
- 2008
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Ingår i: Environmental Health. - 1476-069X. ; 7, s. 62-
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Early-life chemical exposure may influence immune system development, subsequently affecting child health. We investigated immunomodulatory potentials of polychlorinated biphenyls (PCBs) and p,p'-DDE in infants. METHODS: Prenatal exposure to PCBs and p,p'-DDE was estimated from maternal serum concentrations during pregnancy. Postnatal exposure was calculated from concentrations of the compounds in mother's milk, total number of nursing days, and percentage of full nursing each week during the 3 month nursing period. Number and types of infections among infants were registered by the mothers (N = 190). White blood cell counts (N = 86) and lymphocyte subsets (N = 52) were analyzed in a subgroup of infants at 3 months of age. RESULTS: Infants with the highest prenatal exposure to PCB congeners CB-28, CB-52 and CB-101 had an increased risk of respiratory infection during the study period. In contrast, the infection odds ratios (ORs) were highest among infants with the lowest prenatal mono-ortho PCB (CB-105, CB-118, CB-156, CB-167) and di-ortho PCB (CB-138, CB-153, CB-180) exposure, and postnatal mono- and di-ortho PCB, and p,p'-DDE exposure. Similar results were found for pre- and postnatal CB-153 exposure, a good marker for total PCB exposure. Altogether, a negative relationship was indicated between infections and total organochlorine compound exposure during the whole pre- and postnatal period. Prenatal exposure to CB-28, CB-52 and CB-101 was positively associated with numbers of lymphocytes and monocytes in infants 3 months after delivery. Prenatal exposure to p,p'-DDE was negatively associated with the percentage of eosinophils. No significant associations were found between PCB and p,p'-DDE exposure and numbers/percentages of lymphocyte subsets, after adjustment for potential confounders. CONCLUSION: This hypothesis generating study suggests that background exposure to PCBs and p,p'-DDE early in life modulate immune system development. Strong correlations between mono- and di-ortho PCBs, and p,p'-DDE exposures make it difficult to identify the most important contributor to the suggested immunomodulation, and to separate effects due to pre- and postnatal exposure. The suggested PCB and p,p'-DDE modulation of infection risks may have consequences for the health development during childhood, since respiratory infections early in life may be risk factors for asthma and middle ear infections.
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| 3. |
- Morrell, Jane, et al.
(författare)
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Sperm quality variables as indicators of bull fertility may be breed dependent
- 2017
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Ingår i: Animal Reproduction Science. - : ELSEVIER SCIENCE BV. - 0378-4320 .- 1873-2232. ; 185, s. 42-52
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Tidskriftsartikel (refereegranskat)abstract
- A means of discriminating among bulls of high fertility based on sperm quality is needed by breeding centers. The objective of the study was to examine parameters of sperm quality in bulls of known fertility to identify useful indicators of fertility. Frozen semen was available from bulls of known fertility (Viking Genetics, Skara, Sweden): Swedish Red (n = 31), Holstein (n = 25) and Others (one each of Charolais, Limousin, Blonde, SKB). After thawing, the sperm samples were analyzed for motility (computer assisted sperm analysis), plasma membrane integrity, chromatin integrity, acrosome status, mitochondrial activity and reactive oxygen species. A fertility index score based on the adjusted 56-day non-return rate for > 1000 inseminations was available for each bull. Multivariate data analysis (Partial Least Squares Regression and Orthogonal Partial Least Squares Regression) was performed to identify variables related to fertility; Pearson univariate correlations were made on the parameters of interest. Breed of bull affected the relationship of sperm quality variables and fertility index score, as follows: Swedish Red: %DNA Fragmentation Index, r = -0.56, P < 0.01; intact plasma membrane, r = 0.40, P < 0.05; membrane damaged, not acrosome reacted, r = 0.6, P < 0.01; Linearity, r = 0.37, P < 0.05; there was a trend towards significance for Wobble, r = 0.34, P = 0.08. Holstein: Linearity was significant r = 0.46, P < 0.05; there was a trend towards significance for Wobble, r = 0.45, P = 0.08. In conclusion, breed has a greater effect on sperm quality than previously realized; different parameters of sperm quality are needed to indicate potential fertility in different breeds.
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| 4. |
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| 5. |
- Abraham, Maria Celina, et al.
(författare)
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Effect of sperm preparation on development of bovine blastocyst in vitro
- 2016
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Ingår i: Zygote. - 0967-1994 .- 1469-8730. ; 24, s. 825-830
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Tidskriftsartikel (refereegranskat)abstract
- colloids has been used to select normal sperm for assisted reproduction in several species. Animal models can sometimes be used as a preliminary step to investigate sperm preparation methods that are potentially of use for human fertility treatments. In this study bovine semen was prepared using three variants of the single-layer centrifugation sperm selection technique (Small, Mini, Mini-EP) with Bovicoll (Androcoll-B). Computer-assisted sperm motility analysis, the hypo-osmotic swelling test, and the sperm chromatin structure assay were performed on unselected (control) and SLC-selected sperm samples. Mini and Mini-EP gave the highest yield of motile spermatozoa, progressive motility and membrane integrity. In vitro fertilization trials were performed to investigate the fertilizing ability of the frozen-thawed bovine spermatozoa selected with Bovicoll. Mini-SLC (single-layer centrifugation) and swim-up (Control) were performed and cleavage rate and blastocyst rate did not differ significantly between groups. As there was a trend to an increased number of cells in blastocysts in the SLC group, the Mini-SLC method is at least as good as swim-up for selecting frozen-thawed bull spermatozoa for in vitro fertilization (IVF). This method could potentially be used to prepare human sperm for assisted reproduction.
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| 6. |
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| 7. |
- Al-Essawe, Essraa M, et al.
(författare)
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Addition of seminal plasma to thawed stallion spermatozoa did not repair cryoinjuries
- 2018
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Ingår i: Animal Reproduction Science. - : Elsevier BV. - 0378-4320 .- 1873-2232. ; 196, s. 48-58
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Tidskriftsartikel (refereegranskat)abstract
- Freezing and thawing processes induce structural and functional damage to sperm plasma membranes and internal organelles. Adding seminal plasma (SP) has been found to minimize or repair the cryoinjuries in some species. The objective of this study was to investigate whether adding SP from stallions of known freezability after thawing could repair cryoinjuries. Semen was collected from warmblood stallions (n = 8, three ejaculates/stallion) and processed by Single Layer Centrifugation (SLC) to remove SP prior to freezing. Pooled SP (5%) from bad freezer (BF) or good freezer (GF) stallions was added after thawing. Post-thaw sperm quality was assessed by flow cytometry in terms of chromatin integrity (ßI), membrane integrity, mitochondrial membrane potential (MMP), reactive oxygen species (ROS), and MitoSOX. Sperm kinematics were also assessed by computer-assisted sperm analysis. The ßI was lower in SLC control (C) than in BF or GF (P < 0.0001, P < 0.0003 respectively). The proportion of viable spermatozoa with intact cell membranes was higher in C than in SP treated groups (C vs. BF, P = 0.02; C vs GF, P = 0.05). There were fewer spermatozoa with low MMP and more with high MMP for C than GF (P = 0.006). The spermatozoa treated with SP from good freezers produced more ROS than when treated with SP from bad freezers (P = 0.007). Motility parameters were not affected by adding SP. In conclusion, adding SP after thawing does not have a beneficial effect on sperm quality, suggesting an inability to repair stallion sperm cryoinjuries, regardless of whether the SP originated from stallions semen, which has good or bad quality after thawing.
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| 8. |
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| 9. |
- Al-Essawe, Essraa M, et al.
(författare)
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Improved cryosurvival of stallion spermatozoa after colloid centrifugation is independent of the addition of seminal plasma
- 2018
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Ingår i: Cryobiology. - : Elsevier BV. - 0011-2240 .- 1090-2392. ; 81, s. 145-152
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Tidskriftsartikel (refereegranskat)abstract
- Addition of seminal plasma (SP) prior to cryopreservation may influence stallion sperm cryosurvival. The objective of this study was to investigate the addition of pooled SP from "good" or "bad" freezer stallions to spermatozoa selected by single layer centrifugation (SLC) prior to cryopreservation on post-thaw sperm quality. Semen from 12 stallions was collected; 5 mL was frozen as control (C) and the remainder was processed by SLC to remove SP and was divided into three aliquots: i) SLC sample without SP (SLC); ii) SLC plus pooled SP from "good freezer" stallions (SLC-GF); iii) SLC plus pooled SP from "bad freezer" stallions (SLC-BF). After thawing, the following parameters were evaluated: chromatin integrity (DNA fragmentation index; ßI), mitochondria) membrane potential (MMP), membrane integrity (MI), reactive oxygen species (ROS) and sperm kinematics. The ßI was reduced (P < 0.0001) in SLC samples compared to controls. The SLC group showed a lower proportion of spermatozoa with low MMP and a higher proportion of spermatozoa with high MMP than other groups (P < 0.0001), and had lower hydrogen peroxide content than control. Sperm kinematics were not different. In conclusion, selection by SLC prior to cryopreservation improved post-thaw sperm quality; inclusion of SP from "good" and "bad" freezer stallions did not have an additional beneficial effect.
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| 10. |
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