Red Imported Fire Ant Impacts on Upland Arthropods in Southern Mississippi

Red imported fire ants (Solenopsis invicta) have negative impacts on a broad array of invertebrate species. We investigated the impacts of fire ants on the upland arthropod community on 20-40 ha study sites in southern Mississippi. Study sites were sampled from 1997–2000 before, during, and after fire ant bait treatments to reduce fire ant populations. Fire ant abundance was assessed with bait transects on all sites, and fire ant population indices were estimated on a subset of study sites. Species richness and diversity of other ant species was also assessed from bait transects. Insect biomass and diversity was determined from light trap samples. Following treatments, fire ant abundance and population indices were significantly reduced, and ant species diversity and richness were greater on treated sites. Arthropod biomass, species diversity and species richness estimated from light trap samples were negatively correlated with fire ant abundance, but there were no observable treatment effects. Solenopsis invicta has the potential to negatively impact native arthropod communities resulting in a potential loss of both species and function

Red Imported Fire Ant Impacts on Upland Arthropods in Southern Mississippi

Red imported fire ants (Solenopsis invicta) have negative impacts on a broad array of invertebrate species. We investigated the impacts of fire ants on the upland arthropod community on 20-40 ha study sites in southern Mississippi. Study sites were sampled from 1997–2000 before, during, and after fire ant bait treatments to reduce fire ant populations. Fire ant abundance was assessed with bait transects on all sites, and fire ant population indices were estimated on a subset of study sites. Species richness and diversity of other ant species was also assessed from bait transects. Insect biomass and diversity was determined from light trap samples. Following treatments, fire ant abundance and population indices were significantly reduced, and ant species diversity and richness were greater on treated sites. Arthropod biomass, species diversity and species richness estimated from light trap samples were negatively correlated with fire ant abundance, but there were no observable treatment effects. Solenopsis invicta has the potential to negatively impact native arthropod communities resulting in a potential loss of both species and function

Differences in Relative Abundance of GnRH-I and GnRH-II in Granulosa Cells of Bovine Antral Follicles at Specific Stages of Follicular Development

Increased estradiol is the primary signal to initiate standing estrus, and cows that exhibit estrus prior to fixed-time artificial insemination have greater pregnancy rates than cows that do not. Therefore, understanding what factors may be present at the ovary that may regulate estradiol production is critical. A previous study reported that bovine follicles with greater follicular fluid concentrations of estradiol had decreased expression of GnRH-I and GnRH-II in granulosa cells (GC). The objective of this study was to characterize relative abundance of GnRH-I and -II mRNA within GC of follicles at specific stages of development. Beef cows were synchronized, and ovaries were collected at specific stages of follicular development [pre-selection (PRE), post-selection (POST), and post-selection 24 h after luteal regression (POST-PG)]. All surface follicles were classified as small (\u3c 5mm), medium (5 - 8mm), or large (\u3e 8mm) and aspirated to collect GC. Large follicles from each animal were kept separate and all other follicles were pooled by size within animal (n = 27, 27, and 18 for small, medium, and large). Total cellular RNA was extracted, and RT-PCR was performed for GnRH-I, GnRH-II, and GAPDH. Data were analyzed using the MIXED procedure of SAS. Across all follicles, GnRH-I and GnRH-II expression were not influenced by stage (P = 0.27) but were influenced by size (P \u3c 0.01). Smalls (4.55 ± 0.39 and 3.91 ± 0.44, respectively) had greater expression (P ≤ 0.01) of GnRH compared to mediums (0.83 ± 0.39 and 1.41 ± 0.44, respectively) and larges (0.52 ± 0.47 and 2.12 ± 0.54, respectively). There was also a stage by size interaction (P \u3c 0.01). POST (P \u3c 0.01) and POST-PG (P ≤ 0.08) smalls had or tended to have increased expression compared to PRE smalls, but PRE mediums had increased expression (P \u3c 0.03) compared to POST-PG mediums. When only the largest follicle for each animal was evaluated, stage of development influenced expression of GnRH-I (P = 0.03) but not GnRH-II (P = 0.91). For GnRH-I, PRE tended (P = 0.09; 2.29 ± 0.55) to have increased expression compared to POST (0.92 ± 0.55) and did have greater expression compared to POST-PG (P = 0.01; 0.11 ± 0.55). Thus, GnRH within antral follicles may be a key regulator of the follicle’s ability to produce estradiol

Influence of Bovine Viral Diarrhea Virus Infection on Artificial Insemination Conception and Breeding Season Pregnancy Success in Vaccinated Beef Herds

Bovine Viral Diarrhea Virus (BVDV) causes reproductive economic losses in cattle. The objective of this study was to evaluate the influence of BVDV infection on reproductive success. Vaccinated cows (n = 370) and heifers (n = 528) from nine different herds were synchronized using the 7-day CO-Synch + CIDR protocol and were bred using fixed-time artificial insemination (FTAI). On d 28 following insemination, blood samples were collected and pregnancy status was determined. Non-pregnant animals were resynchronized and FTAI occurred a second time. In six herds, bulls were comingled with females beginning 10-15 d after the second AI. Final pregnancy status was determined 33-80 d following the first pregnancy diagnosis. Blood samples were tested for the presence of BVDV antigen using the IDEXX BVDV PI X2 Kit. Animals that tested positive were considered infected with BVDV at the time of blood collection. Herds were determined to be BVDV infected by the presence of at least one animal having a positive test for antigen (n = 4 infected herds, n = 5 non-infected herds). Statistical analyses were performed using the GLIMMIX procedure of SAS with herd as a random variable. Herds that had evidence of BVDV infection at d 28 following insemination had significantly decreased (P \u3c 0.01) first service AI conception rates compared to herds that had no evidence of infection (34 ± 2.3% vs. 54 ± 2.3%, respectively). Additionally, breeding season pregnancy rates were decreased (P \u3c 0.01) in BVDV infected herds compared to non-infected herds (69 ± 3.4% vs. 80 ± 3.6%, respectively). There was no significant effect of BVDV infection status on embryonic loss (P = 0.42) or percentage of animals which lost a pregnancy and rebred by the end of the breeding season (P = 0.63). In conclusion, BVDV infection in well vaccinated herds had a significant negative impact on both first service AI conception rate and overall breeding season pregnancy success

The Interactions of Change in Nutrition on Uterine Environment and Cholesterol Concentrations in Beef Cattle

The objective of this study was to evaluate the impact of nutritional changes prior to and after artificial insemination (AI) on uterine environment and plasma cholesterol concentrations

Решение оптимизационных задач для систем массового обслуживання с отказами в условиях неопределенности

Построены математические модели расчета показателей качества функционирования вычислительных сетей, которые можно представить в виде сетей массового обслуживания с отказами. Сформулированы задачи оптимизации показателей качества функционирования таких сетей при заданных ограничениях на максимальную пропускную способность каналов связи и на выделяемые для модернизации сети ресурсы. Построены алгоритмы, которые позволяют решать поставленные оптимизационные задачи в рамках оговоренных ограничений

Revisiting the spectrum of bladder health: Relationships between lower urinary tract symptoms and multiple measures of well-being

Background: Little research to date has investigated the spectrum of bladder health in women, including both bladder function and well-being. Therefore, we expanded our previous baseline analysis of bladder health in the Boston Area Community Health (BACH) Survey to incorporate several additional measures of bladder-related well-being collected at the 5-year follow-up interview, including one developed specifically for women. Methods: At follow-up, participants reported their frequency of 15 lower urinary tract symptoms (LUTS), degree of life impact from and thought related to urinary symptoms or pelvic/bladder pain/discomfort, and perception of their bladder condition. Prevalence ratios were calculated by generalized linear models with robust variance estimation, adjusting for LUTS risk factors and individual LUTS. The BACH Survey was approved by the New England Research Institutes Institutional Review Board and all participants provided written informed consent. Results: Generally similar findings were observed in the 5-year cross-sectional analysis as at baseline, irrespective of how we categorized LUTS or measured bladder-related well-being. Approximately one in five women (16.2%-18.0% of 2527 eligible women) reported no LUTS and no diminished bladder-related well-being, the majority (55.8%-65.7%) reported some LUTS and/or diminished well-being, and a further one in five (16.9%-26.6%) reported the maximum frequency, number, or degree of LUTS and/or diminished well-being. Measures of storage function (urinating again after <2 hours, perceived frequency, nocturia, incontinence, and urgency) and pain were independently associated with bladder-related well-being. Conclusions: Our similar distribution of bladder health and consistent associations between LUTS and bladder-related well-being across multiple measures of well-being, including a female-specific measure, lend confidence to the concept of a bladder health spectrum and reinforce the bothersome nature of storage dysfunction and pain

Matching schemes and public goods : a review

Matching schemes, where a party matches the contribution of others, reduce the effective price of a good and aim to foster its demand. We review the empirical literature on the effectiveness of these schemes in the context of public goods, especially in the field of charitable giving. As different measures of effectiveness are used, we classify results according to (i) the level of public good provision, (ii) the amount of individuals' contributions, (iii) the likelihood to give and (iv) the contribution conditional on contributing a positive amount. Generalizing results is challenging, since context specific factors matter. Predominantly, a match is found to create a significant increase in public good provision without crowding out individuals' contributions, while the effect on the likelihood of giving and contribution condition on contributing a positive amount is nonnegative. The discussion reveals several avenues for future research, as putting stronger emphasizes on long term effects, public good competition or heterogeneity in responses

The spectrum of bladder health: The relationship between lower urinary tract symptoms and interference with activities

Background: Little research to date has focused on lower urinary tract symptom (LUTS) prevention and bladder health promotion in women. To address this gap, the Prevention of LUTS Research Consortium developed the following working bladder health definition: "A complete state of physical, mental, and social well-being related to bladder function [that] permits daily activities [and] allows optimal well-being." To begin to inform and quantify this definition, we used data from the Boston Area Community Health Survey, drawing upon its rare collection of information on LUTS and LUTS-specific interference with activities. Methods: At baseline, participants reported their frequency of 15 LUTS and interference with 7 activities. Prevalence ratios (PRs) were calculated by generalized linear models with robust variance estimation, adjusting for LUTS risk factors and individual LUTS. Results: Of the 3169 eligible participants, 17.5% reported no LUTS or interference, whereas the remaining 82.5% reported some frequency of LUTS/interference: 15.1% rarely; 21.7% a few times; 22.6% fairly often/usually; and 22.9% almost always. LUTS independently associated with interference were urgency incontinence, any incontinence, urgency, nocturia, perceived frequency, and urinating again after <2 hours (PRs = 1.2-1.5, all p < 0.05). Conclusions: Our findings suggest that bladder health exists on a continuum, with approximately one in five women considered to have optimal bladder health (no LUTS/interference), the majority to have intermediate health (LUTS/interference rarely to usually), and a further one in five to have worse or poor health (LUTS/interference almost always). These findings underscore the need for LUTS prevention and bladder health promotion