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The sympathetic nervous system plays a major role in blood pressure regulation. Beta 2 (β2) adrenoceptor gene polymorphisms have been associated with hypertension in different populations with conflicting results. We examined the association of three common polymorphisms, Arg16Gly, Gln27Glu, and Thr164Ile, of the β2 adrenoceptor gene in Malaysian hypertensive subjects. A total of 160 hypertensive and control subjects were recruited. Systolic blood pressure (SBP), diastolic blood pressure (DBP), and anthropometric measurements were obtained from each subject. Biochemical analyses of lipid profiles were conducted with an autoanalyzer. DNA samples were extracted from blood and buccal cells. Genotyping was accomplished with polymerase chain reaction-restriction fragment length polymorphism. SBP, DBP, body mass index, and biochemical factors all differed significantly between case and control subjects (P < 0.05). The genotype frequencies of Arg16Arg, Arg16Gly, and Gly16Gly were 22.5, 70, and 7.5% among cases and 33.1, 63.1, and 3.8% among controls, respectively. The genotype frequencies of Gln27Gln, Gln27Glu, and Glu27Glu among cases were 41.1, 50, and 1.9% compared to 77.5, 20.6, and 1.9% among controls, respectively. In this study, the Gln27Glu polymorphism was significantly associated with Malaysian hypertensive subjects (P < 0.05). Therefore, the Gln27Glu polymorphism of the β2 adrenoceptor could be a risk factor associated with hypertension among Malaysians.

International audience; Generally, once-daily milking (ODM) decreases milk yield. This effect may be the consequence of a decrease in mammary epithelial cell (MEC) activity or a reduction in their number. The aim of this study was to determine the effect of ODM on the synthetic activity and rate of apoptosis of MEC using a non-invasive method. Eight Alpine goats were subjected to ODM or twice-daily milking for two 5-week periods. MECs were purified by centrifugation and immunocytochemical binding in milk after 1 and 5 weeks of each period. mRNA levels of some proteins involved in lactose and milk protein synthesis and in apoptosis were evaluated using real-time PCR. Isolation of MEC from milk was a useful method to investigate transcriptional regulation in a timeline study. ODM induced greater decreases in milk, lactose and protein yields after 1 week than after 5 weeks. This suggests an adaptation of the mammary gland to ODM, which reduces the inhibitory effect of this practice. Reductions in milk component yields were associated with lower a-lactalbumin transcripts, suggesting a transcriptional decrease of lactose synthesis during ODM. Glucose transporter GLUT1 transcripts were downregulated under ODM, suggesting that lactose precursor uptake by MEC might be involved in the regulation of lactose synthesis. kappa-Casein mRNA levels tended to be lower during ODM. ODM increased levels of the pro-apoptotic transcript Bax after both 1 and 5 weeks, but no variation was observed in the Bax/Bcl-2 ratio. ODM affected cell synthetic activity through transcriptional regulation and may have induced apoptosis. The reduction of the negative effect of ODM on milk yield suggests that Alpine goats are able to adapt to ODM. Further studies are needed to investigate the effect of ODM on MEC turnover.

This study investigated the combined effects of once-daily milking and feeding level ( ad libitum or adjusted) on goat welfare and milk emission characteristics in late lactation. Forty dairy goats housed in individual pens were managed under twice-daily milking and fed ad libitum during a pre-experimental period (2 weeks). The experiment was then divided into two successive periods: a 1-week period of milking frequency reduction and a 3-week period of feed adjustment. During the first period, half the goats were managed under once-daily milking. During the second period, half the goats of each type of milking treatment was fed ad libitum , whereas the other half received a quantity of feed adjusted weekly to milk production. The following measurements were taken for all goats: milk yield, dry matter intake (DMI), somatic cell count (SCC), plasma cortisol concentrations before morning milking, milk flow parameters [latency (i.e., the time from teat cup attachment to first measurement of the milk with a jar), the maximum milk flow rate (MAXFR) and the time taken to reach this maximum (TMAX)] and goat behaviour at morning milking (number of goats ruminating, back hunching, foot moving or kicking at milking). In addition, the time–budget (time spent drinking, eating, standing, lying or climbing) of 16 goats was measured by video recording. Milk yield was reduced by once-daily milking (18 and 21% in the first and the second period, respectively) but not by feed adjustment. DMI was reduced by once-daily milking (12%) only during the second period or by feed adjustment (28%) during the same period. Both SCC and latency were not modified by once-daily milking nor feed adjustment. MAXFR was increased by once-daily milking but not modified by feed adjustment. TMAX was increased by once-daily milking only during the first period and reduced by feed adjustment during the second one. The time spent eating was reduced by once-daily milking or feed adjustment during the second period, in agreement with the reduction in DMI in this period. There were no effects of milking frequency or feeding level on plasma cortisol concentrations, the behaviour at morning milking or the time spent drinking, standing, lying or climbing. No welfare impairment was demonstrated under our experimental conditions in late lactation dairy goats under a once-daily milking management strategy whatever the feeding level.

This paper aims to compare different adaptive responses of the mammary gland of cows, ewes, and goats submitted to extended milking intervals in different systems of management. Depending on the species, these extended milking intervals can be characterized by the following milk removal approaches; 3 milkings every 2 d, elimination of 1 milking per week (i.e., 13 vs. 14 milkings per week), and once-daily milking with additional suckling (i.e., dual purpose system of suckling and milking) or without suckling (exclusive once-daily milking). All the high-yielding animals and breeds adapted without problems to being submitted to intervals between milking less than 20 to 21 h. Under these conditions, all ruminant species demonstrated only low and transitory variations in milk production and quality. Thus, management systems using such an interval are good tools for the dairy producer who wants to save time without important adverse economic impact. When animals have good mammary gland health, these management systems can be applied without preliminary adaptation. However, goats and some breeds of dairy ewes seem to adapt to once-daily milking better than cows. Additionally, goats and ewes with higher production levels demonstrate a lower reduction in milk yield. With goats, there is only a limited variation in milk quality and cheese-making capacity of the milk produced, but ewes and cows show a significant enrichment of milk constituents, especially in fat. This indicates some differences in the regulation of lactose, protein, and fat synthesis depending on the duration of the milking interval and provides interesting models for physiological studies on milk secretion and synthesis regulation. Anatomical and physiological characteristics of lactating cows and ewes, in terms of cisternal vs. alveolar volumes within the mammary glands, could contribute to different abilities in adaptation to different milking systems. In goats, however, other mechanisms, such as compliancy of the mammary gland and regulation of tight junction impermeability, could be involved in milk secretion regulation and, thus, could become new targets for genetic selection of animals better adapted to accept extended milking intervals.

Two experiments were conducted to determine the milk loss of high-yielding Alpine goats resulting from once-daily milking (ODM) and its relationship to udder cisternal size. We investigated the effects of application of this management strategy on milk yield, composition, and technological parameters: lipolysis, fat globule size, and cheese yield. In a second experiment, we investigated the effect of repeated periods of ODM management during lactation. Goats at the beginning of both experiments were at 25 d in milk on average and were previously milked twice daily (twice-daily milking; TDM). In experiment 1, which was conducted for 2 periods (P) of 9 wk (P1, P2), 48 goats were grouped (1, 2, 3, and 4) according to milk yield, parity, and somatic cell count (SCC). Over the 2 periods, goats from group 1 were managed with TDM and those from group 2 were managed with ODM. In group 3, goats were assigned to TDM during P1 and ODM during P2, conversely, those in group 4 were assigned to ODM in P1 and TDM in P2. During P1, the 12 goats from group 3 underwent 2 distinct morning machine milkings to measure milk repartition (cisternal and alveolar) in the udder based on the "atosiban method." On P1 plus the P2 period of 18 wk, milk loss caused by ODM (compared with TDM) was 16%. In our condition of 24-h milk accumulation, there was no correlation between milk loss and udder cisternal size. Milk fat content, fat globule size, or apparent laboratory cheese yield was not modified by ODM, but milk protein content (+2.7 g/kg), casein (+1.8 g/kg), milk soluble protein concentration (+1.0 g/kg), and SCC increased, whereas lipolysis decreased (-0.3 mEq/100 g of oleic acid). In experiment 2, which was conducted for 4 periods (P1, P2, P3, P4) of 5 wk each, 8 goats, blocked into 2 homogenous groups (5 and 6), were used to study the effects of a double inversion of milking frequency (TDM or ODM) for 20 wk of lactation. Milk loss was 17% and ODM did not modify milk fat or protein contents, SCC, casein, or milk soluble protein concentration, but lipolysis was decreased (-0.3 mEq/100 g of oleic acid). Neither experiment showed the effects of period of ODM management on milk yield, milk fat or protein content, SCC, fat globule size, lipolysis, casein, milk soluble protein concentration, or apparent laboratory cheese yield.

International audience; This study was done to verify if the lack of increase of milk fat content observed in Alpine dairy goats under once daily milking (ODM) compared to twice daily milking (TDM), results from disturbances of animals and/or milk ejection reflex. In this respect, we determined the milk yield and composition in the same 12 multiparous Alpine dairy goats when they were managed first under TDM (period 1: P1) and then under ODM (period 2: P2). Furthermore, oxytocin (OT) and cortisol (CORT) releases and milk emission kinetic of these goats were measured at morning milking 2 and 4 times in P1 and P2, respectively. ODM compared to TDM, caused 18 and 23% reductions, respectively in daily milk yield and milk fat content without milk protein content modification. Although baseline concentration of blood OT was lower under ODM than TDM management (7.0 pg/mL vs 17.8 +/- 2.0 pg/mL, respectively), ODM did not modify the total amount of OT released during milking (15,484 pg/mL/32 min vs 18,996 +/- 2865.3 pg/mL/32 min, respectively), the peak concentration of OT (57.2 pg/mL vs 73.6 +/- 10.5 pg/mL, respectively) or the time to reach it (3.0 min vs 2.0 +/- 0.5 min, respectively) by comparison to TDM. ODM compared to TDM, never modified the baseline concentrations of CORT (6.1 ng/mL vs 7.1 +/- 1.1 ng/mL. respectively), the total amount of CORT released (11,727 ng/mL/32 min vs 10,073 +/- 1522.2 ng/mL/32 min. respectively), the peak concentrations of CORT (16.1 ng/mL vs 15.1 +/- 2.1 ng/mL, respectively) and the time to reach it (13.1 min vs 11.0 +/- 1.5 min). During ODM, milk flow latency was reduced (-61%) while the mean flow rate was increased (+28%) by comparison to TDM. CDM compared to TDM management, did not modify the maximum flow rate (1.6 L/min vs 1.6 +/- 0.2 L/min, respectively) or the time to reach this maximum (103.0 s vs 95.0 +/- 10.0 s, respectively). The total milking duration at morning milking was not different (250.0 s vs 221.0 +/- 22.0 s, respectively) although the morning milk yield was significantly higher under ODM management (2.63 kg/d vs 1.87 +/- 0.1 kg/d. respectively). This results show that milk emission is improved under ODM management in Alpine goats without inhibition or disturbance of neuro-hypophyseal OT release pattern and lack of activation of the hypothalamic-pituitary-ad renal axis and plasma cortisol increase, disproving our initial hypotheses of a disturbance of animals and/or incomplete milk ejection to explain the low fat content of milk under ODM in this breed. (C) 2009 Elsevier B.V. All rights reserved.

International audience; This paper aims to compare different adaptive responses of the mammary gland of cows, ewes, and goats submitted to extended milking intervals in different systems of management. Depending on the species, these extended milking intervals can be characterized by the following milk removal approaches; 3 milkings every 2d, elimination of 1 milking per week (i.e., 13 vs. 14 milkings per week), and once-daily milking with additional suckling (i.e., dual purpose system of suckling and milking) or without suckling (exclusive once-daily milking). All the high-yielding animals and breeds adapted without problems to being submitted to intervals between milking less than 20 to 21 h. Under these conditions, all ruminant species demonstrated only low and transitory variations in milk production and quality. Thus, management systems using such an interval are good tools for the dairy producer who wants to save time without important adverse economic impact. When animals have good mammary gland health, these management systems can be applied without preliminary adaptation. However, goats and some breeds of dairy ewes seem to adapt to once-daily milking better than cows. Additionally, goats and ewes with higher production levels demonstrate a lower reduction in milk yield. With goats, there is only a limited variation in milk quality and cheese-making capacity of the milk produced, but ewes and cows show a significant enrichment of milk constituents, especially in fat. This indicates some differences in the regulation of lactose, protein, and fat synthesis depending on the duration of the milking interval and provides interesting models for physiological studies on milk secretion and synthesis regulation. Anatomical and physiological characteristics of lactating cows and ewes, in terms of cisternal vs. alveolar volumes within the mammary glands, could contribute to different abilities in adaptation to different milking systems. In goats, however, other mechanisms, such as compliancy of the mammary gland and regulation of tight junction impermeability, could be involved in milk secretion regulation and, thus, could become new targets for genetic selection of animals better adapted to accept extended milking intervals.

The Indonesian geoid model (INDGED96) has been constructed from the Indonesian gravity database of 5′ grid interval. The accuracy of the geoid height is considered poor in some areas due to the lack of high resolution gravity data in the areas. In order to improve the geoid model, additional gravity data must be performed. Since the data gaps occur mostly in mountainous remote areas, performing terrestrial observation will be very time consuming. In this case, implementing airborne gravimetry is an alternative to accelerate the data acquisition. However, the accuracy of the airborne derived gravity data used for geophysical exploration purposes might not be suitable for the precise geoid determination. A case study of the airborne gravity data aimed at hydrocarbon allocation in Irian Jaya used to calculate the geoid height is undertaken. The preliminary result is presented.

Abstract In light of the inverse solution theory, an efficient solution procedure has been developed to generate reservoir descriptions conditioned to statistics for rock properties, hard data, and dynamic data. The technique yields realizations for wellbore skin factors at each active well, porosity, and permeability which honor a priori information and dynamic production data. The technique uses inverse solution theory to construct the objective function and uses a gradient method to generate the maximum a posteriori estimates. Differing from previous work, we derived and implemented a two-loop iteration method to perform the minimization. By using Krylov space based methods to solve the linear part involved in the minimization, the explicit construction of the sensitivity coefficient matrix is avoided. Complexity analysis indicates that although the limitations suffered by the procedures using GPST or Carter's methods to construct the sensitivity coefficient matrix are completely removed, the new method is as efficient as those procedures. More significantly, the new method can be easily adapted to multi-phase flow conditions. We also developed a modified procedure for computing realizations using a Chebyshev approximation of the decomposed a posteriori covariance matrix. In this way, the expensive computational cost of construction and decomposition of an a posteriori covariance matrix are avoided. When estimating multiple categories of parameters, as is the case in this study, our new procedure produces much more accurate results than the conventional Chebyshev method. Introduction The most commonly encountered and probably the most challenging work in the management of a mature reservoir is to effectively and efficiently implement various feasible IOR techniques and assess the impact of such implementations on the further performance of the reservoir. To this end, an accurate reservoir description is essential. The description should include at least major localized discontinuities such as faults, fractures, and bounding surfaces, as well as facies distributions, rock property distributions within the facies and rock-fluid properties. Due to the complex nature of the multiple scales of heterogeneity inherent to petroleum reservoirs, different production processes may be sensitive to different scales of heterogeneities, therefore, theoretically, we need an infinite dimensional model space to adequately describe the real reservoir. In reality, what we can do, at best, is to generate an equivalent description of the reservoir at a scale that is suitable to the production process in which we are interested. In other words, we partition the reservoir into a proper gridblock system, and then search the discrete reservoir model corresponding to the partitioned system. Limited by technology and expense, generating reservoir description based on the direct measurements of the reservoir properties is impractical. Therefore, we are forced to perform the task of transferring to model space, via theoretical correlation, the prior information and the information carried in indirect data sets. By definition, such a process is referred to as an inverse procedure. The information is usually divided into two classes: prior information and dynamic information. The former includes all the phenomenological information and static data; the later includes production data, pressure transient data, tracer testing data, etc. Although the prior information plays a critical role in the inverse process, both as a mathematical necessity for stabilizing the ill-posed problems and reducing the dimension of the model space and as a requirements for geological and logical consistencies. The reservoir description based on prior information only will usually provide a unrealistic smooth version of the "true" reservoir model with high uncertainty. P. 193