An Investigation of a Repeat Breeder Problem in Dairy Cows

Repeat breeding in dairy cows is still a major problem and causes substantial economic loss through increase in calving interval and reduction in milk yield. Although factors related to the bull and the environment have been implicated, the majority of the research has shown that the cow plays a major part in the repeat breeding syndrome. Since Lindhal (1966) first reported the use of ultrasonography in detection of pregnancy in sheep, the technique has gained popularity in veterinary medicine as a diagnostic aid. However, due to the additional equipment cost compared to rectal palpation, it has rarely been used on a commercial basis for diagnosis of reproductive disorders in cows. The purpose of this study was to compare the reproductive events in normal and repeat breeder cows using ultrasonography and plasma progesterone concentration. Cows were divided into two groups and were bled and scanned regularly. Group one consisted of normal cows and group two consisted of repeat breeder cows. The cows that conceived in both groups were observed from day of insemination up to day 42 post-insemination whereas those that did not conceive were only observed till they returned to service again. All the cows in group one and two cows from group two conceived, though one of the repeat breeder cows had lost an earlier conceptus but held to the next service. One cow from group two lost the conceptus and developed a luteal cyst during the period of observation. Three other cows from group two did not conceive. Two of them returned to service between day 20 and day 23 while the third cow was not seen on heat by the herdsman during the period of observation. In the pregnant cows, the area, height and width of the corpus luteum, as measured by ultrasound, fluctuated throughout the period of observation but the plasma progesterone concentration remained elevated. In the cows that did not conceive, the corpus luteum, as seen by ultrasound, reduced in size, decreased in echogenicity and its outline became blurred as the next oestrus drew nearer. In addition, in these cows the plasma progesterone concentration declined rapidly and reached basal levels as the next oestrus approached. More follicular activity was evident in non-pregnant cows than in pregnant cows. In the pregnant cows the ovary contra-lateral to the corpus luteum bearing ovary showed more follicular activity. The uterus in oestrus, dioestrus and pregnancy was found to exhibit characteristic images. These included a distinct folding of the endometrium and accumulation of intra-uterine fluid during oestrus and lack of folding and fluid during dioestrus. The embryonic vesicle was seen as early as day 13 in the pregnant cows and the embryo proper was detected by day 20. This study demonstrated that ultrasonography in collaboration with plasma progesterone concentration was useful in monitoring the reproductive events in both normal and repeat breeder cows. Although additional cost of the equipment currently precludes the complete replacement of bovine rectal palpation by ultrasound, ultrasonography can augment rectal palpation and endocrinology in individual animals that present diagnostic problems. Further studies are needed to confirm, clarify and extend the findings reported and to justify the commercial use of ultrasonography in monitoring herd fertility

Trial Sequential Analysis Comparing Bleeding and Major Adverse Cardiovascular Events in Patients with Atrial Fibrillation and Acute Coronary Syndrome on Dual versus Triple Therapy

Objective To assess efficacy and safety of dual therapy (DT) and triple therapy (TT) in patients with atrial fibrillation (AF) and acute coronary syndrome (ACS) with or without percutaneous coronary intervention (PCI) and evaluate the quality of evidence with respect to said outcomes based on contemporary randomized trials (RCTs). The efficacy outcome taken was major adverse cardiovascular events (MACE) while safety outcome was major bleeding events. Introduction Appropriate anti-thrombotic therapy is still controversial in patients with AF and concomitant ACS or PCI. We conducted a conventional meta-analysis pooling data from major RCTs to assess the efficacy and safety of DT and TT. Additionally, we utilized advanced analytic properties of trial sequential analysis (TSA) to assess for quality of evidence in this realm. Methods and results A total of 8,732 patients from five major RCTs were enrolled in this study. There was a statistically significant reduction in major bleeding on the DT group compared to the TT group (RR 0.65, 95% CI 0.48, 0.86). The incidence of major adverse cardiovascular events (MACE) was similar in both groups (RR 0.97, 95% CI 0.8,1.17). The trial sequential analysis showed strong evidence supporting reduction in bleeding from current major RCTs while being inconclusive based on MACE outcome. Conclusion Sufficient quality evidence could be ascertained from contemporary RCTs on reduced incidence of bleeding in DT patients compared to TT patients. Further adequately powered RCTs are needed to ensure non-inferiority of DT over TT with respect to MACE outcome

Accounting B

Exam paper for second semeste

Effects of Chronic Low Dose Anti-Telomerase and Chemotherapeutic Drugs on Breast Cancer Cells

Breast cancer is the second leading cause of death among women in the United States. Among the different molecular sub-groups of breast cancer, the most invasive is Triple-Negative Breast Cancer (TNBC). TNBC has the worst prognosis, decreased overall survival rate and no targeted therapy available. On-going research is investigating new strategies and therapies for TNBC. Therefore, this study’s objective was to compare and contrast the effects of continuous low-dose of BIBR 1532, a novel analogue of BIBR1532 (GV6), Paclitaxel and Doxorubicin on breast cancer (MDA-MB 231) cells. Culture flasks (T-25) were seeded with approximately 5.0x105 cells/ml and supplemented with GV6 (n=4-8) or BIBR 1532 (n=4-8) or Doxorubicin (n=4-8) or Paclitaxel (n=4-8) or non-drug supplemented media (Control, n=4-8) for 21 days. Trypan Blue (Gibco) exclusion test was utilized to assess the viability of the cells. BIBR 1532, Doxorubicin and Paclitaxel reduced (P\u3c0.05) proliferation of the cancer cells by approximately 20-35% by day 7 of treatment compared to the Control. By day 21 of low-dose GV6, BIBR1532, Doxorubicin and Paclitaxel supplementation, the cell counts dropped to about 25% (P\u3c0.05), 55% (P\u3c0.05), 75% (P\u3c0.05) and 50% (P\u3c0.05) of Control, respectively. Our results indicate that continuous low dose anti-telomerase and chemotherapeutic drugs do inhibit breast cancer cell proliferation and merits further investigation

Formal reliability analysis of combinational circuits using theorem proving

Reliability analysis of combinational circuits has become imperative these days due to the extensive usage of nanotechnologies in their fabrication. Traditionally, reliability analysis of combinational circuits is done using simulation or paper-and-pencil proof methods. But, these techniques do not ensure accurate results and thus may lead to disastrous consequences when dealing with safety-critical applications. In this paper, we mainly tackle the accuracy problem of these traditional reliability analysis approaches by presenting a formal reliability analysis framework based on higher-order-logic theorem proving. We present the higher-order-logic formalization of the notions of fault and reliability for combinational circuits and formally verify the von-Neumann fault models for most of the commonly used logic gates, such as, AND, NOT, OR, etc. This formal infrastructure is then used along with a computer program, written in C++, to automatically reason about the reliability of any combinational circuit within a higher-order-logic theorem prover (HOL). For illustration purposes, we utilize the proposed framework to analyze the reliability of a few benchmark combinational circuits

A CMOS compatible ultracompact silicon photonic optical add-drop multiplexer with misaligned Sidewall Bragg gratings

We experimentally and via simulations demonstrate ultracompact single-stage and cascaded optical add-drop multiplexers using misaligned sidewall Bragg grating in a Mach-Zehnder interferometer for the silicon-on-insulator platform. The single-stage configuration has a device footprint of 400 μm × 90 μm, and the cascaded configuration has a footprint of 400 μm × 125 μm. The proposed designs have 3-dB bandwidths of 6 nm and extinction ratios of 25 dB and 51 dB, respectively, and have been fabricated for the transverse electric mode. A minimum lithographic feature size of 80 nm is used in our design, which is within the limitation of 193 nm deep ultraviolet lithography

Engineering Symmetry-Selective Couplings of a Superconducting Artificial Molecule to Microwave Waveguides

Tailoring the decay rate of structured quantum emitters into their environment opens new avenues for nonlinear quantum optics, collective phenomena, and quantum communications. Here, we demonstrate a novel coupling scheme between an artificial molecule comprising two identical, strongly coupled transmon qubits and two microwave waveguides. In our scheme, the coupling is engineered so that transitions between states of the same (opposite) symmetry, with respect to the permutation operator, are predominantly coupled to one (the other) waveguide. The symmetry-based coupling selectivity, as quantified by the ratio of the coupling strengths, exceeds a factor of 30 for both waveguides in our device. In addition, we implement a Raman process activated by simultaneously driving both waveguides, and show that it can be used to coherently couple states of different symmetry in the single-excitation manifold of the molecule. Using that process, we implement frequency conversion across the waveguides, mediated by the molecule, with efficiency of about 95%. Finally, we show that this coupling arrangement makes it possible to straightforwardly generate spatially separated Bell states propagating across the waveguides. We envisage further applications to quantum thermodynamics, microwave photodetection, and photon-photon gates