The Effect Of 3d Printing Machine Parameters In Extrusion Process Of Biocomposite Materials (Pmma And Ha) On Dimensional Accuracy

Bone implants are medical procedures involving replacement or reconstruction of missing or damaged bones with the patient's ones, natural substitutes or artificial substitutes. The widely used bone cement is a polymethylmethacrylate (PMMA) based composite material. To improve bioactivity, PMMA is combined with hydroxyapatite (HA). The manual formation can make bone implants during surgery. However, the method requires a longer operation time and raises the possibility of a higher error. Therefore, 3D printing technology is used to improve the quality of bone implants. One of the machines that can be used is the 3D printing machine, the property of the Product Design and Development Laboratory of Universitas Gadjah Mada. This machine needs to be tested to determine the accuracy of the prints, which is one indicator of product quality. Several machine parameters can be set in this machine setting. This study aims to determine the effect of three parameters, those are perimeter speed or edge print speed (20-40 mm / s), infill speed or inner print speed (50 - 70 mm / s), and fill angle or inner slope of inner printing (45 - 90 ° C). Before printing complex shapes, the machine was tested in advance with a more straightforward specimen design, which is a specimen design of flexural strength test. Response surface experiment design is used to determine the effect of three parameters on the dimensional accuracy which is measured through dimensional error. The results show that these three factors have no significant impact on the dimensional error, but the resulting error is still high. Therefore, it is necessary to adjust the design size before printing

Optical pulse-shaping for internal cooling of molecules

We consider the use of pulse-shaped broadband femtosecond lasers to optically cool rotational and vibrational degrees of freedom of molecules. Since this approach relies on cooling rotational and vibrational quanta by exciting an electronic transition, it is most easily applicable to molecules with similar ground and excited potential energy surfaces, such that the vibrational state is usually unchanged during electronic relaxation. Compared with schemes that cool rotations by exciting vibrations, this approach achieves internal cooling on the orders-of- magnitude faster electronic decay timescale and is potentially applicable to apolar molecules. For AlH+, a candidate species, a rate-equation simulation indicates that rovibrational equilibrium should be achievable in 8 \mu s. In addition, we report laboratory demonstration of optical pulse shaping with sufficient resolution and power for rotational cooling of AlH+

A fruticultura como alternativa para a produção familiar no âmbito do Pronaf nos municípios de Campos dos Goytacazes e São Francisco do Itabapoana — RJ.

O trabalho analisa a importância do cultivo de frutas como alternativa para o aumento de renda da agricultura familiar, no contexto dos financiamentos concedidos pelo PRONAF. Os resultados evidenciaram que o recurso financeiro foi a variável que mais limitou a escolha dos agricultores. Maracujá, goiaba e pinha foram identificadas como as melhores alternativas econômicas para os produtores familiares da região. A análise permitiu concluir que a concessão do crédito, pelo PRONAF, contribui para a melhor utilização dos recursos, para a obtenção de maior renda, bem como para a geração de empregos

A Multiwavelength View of a Mass Outflow from the Galactic Center

The Galactic center (GC) lobe is a degree-tall shell of gas that spans the central degree of our Galaxy. It has been cited as evidence for a mass outflow from our GC region, which has inspired diverse models for its origin. However, most work has focused on the morphology of the GC lobe, which has made it difficult to draw strong conclusions about its nature. Here, I present a coherent, multiwavelength analysis of new and archival observations of the GC lobe. Radio continuum emission shows that the GC lobe has a magnetized layer with a diameter of 110 pc and an equipartition field strength ranging from 40 to 100 $\mu$G. Recombination line emission traces an ionized shell nested within the radio continuum with diameter of 80 pc and height 165 pc. Mid-infrared maps at 8 and 15 $\mu$m show that the GC lobe has a third layer of warm dust and PAH-emission that surrounds the radio continuum shell with a diameter of 130 pc. Assuming adiabatic expansion of the gas in the GC lobe, its formation required an energy input of about $5\times10^{52}$ ergs. I compare the physical conditions of the GC lobe to several models and find best agreement with the canonical starburst outflow model. The formation of the GC lobe is consistent with the currently observed pressure and star formation rate in the central tens of parsecs of our Galaxy. Outflows of this scale are more typical of dwarf galaxies and would not be easily detected in nearby spiral galaxies. Thus, the existence of such an outflow in our own Galaxy may indicate that it is relatively common phenomenon in the nuclei of spiral galaxies. (Abridged)Comment: Accepted to ApJ. 15 pages, 8 (compressed) figure

Revisiting the SN1987A gamma-ray limit on ultralight axion-like particles

We revise the bound from the supernova SN1987A on the coupling of ultralight axion-like particles (ALPs) to photons. In a core-collapse supernova, ALPs would be emitted via the Primakoff process, and eventually convert into gamma rays in the magnetic field of the Milky Way. The lack of a gamma-ray signal in the GRS instrument of the SMM satellite in coincidence with the observation of the neutrinos emitted from SN1987A therefore provides a strong bound on their coupling to photons. Due to the large uncertainty associated with the current bound, we revise this argument, based on state-of-the-art physical inputs both for the supernova models and for the Milky-Way magnetic field. Furthermore, we provide major amendments, such as the consistent treatment of nucleon-degeneracy effects and of the reduction of the nuclear masses in the hot and dense nuclear medium of the supernova. With these improvements, we obtain a new upper limit on the photon-ALP coupling: g_{a\gamma} < 5.3 x 10^{-12} GeV^{-1}, for m_a < 4.4 x 10^{-10} eV, and we also give its dependence at larger ALP masses. Moreover, we discuss how much the Fermi-LAT satellite experiment could improve this bound, should a close-enough supernova explode in the near future.Comment: Accepted for publication in JCAP (December 22nd, 2014

A QUANTITATIVE STUDY ON THE RELATIONSHIP BETWEEN COREQUISITE SUPPORT COURSES AND COLLEGE ALGEBRA SUCCESS

Corequisite support courses have been used as an intervention in higher education to improve gateway college math course completion and reduce the time necessary to do so. While a substantial amount of research on the effectiveness of corequisite support exists, it has largely focused on non-STEM courses. This study was designed to further investigate the effectiveness of corequisite support courses but in the context of STEM courses like College Algebra. Specifically, the study explored the role of taking a corequisite version of College Algebra, with and without the consideration of a student’s initial placement, on both the probability of passing College Algebra as well as re-enrolling at the institution. Additional control variables, including age, entering weighted high school GPA, race, biological sex, and federal financial aid use, were studied using binary logistic regression to determine the relationship between other predictors beyond course approach and initial placement. Key findings include no statistically significant difference in the likelihood of passing nor the likelihood of re-enrolling between students in corequisite and non-corequisite sections. When including initial placement, there was a significant difference in the chance of passing amongst non-corequisite students who had previously taken developmental math courses and those in the corequisite sections. Further quantitative studies are recommended at other types of institutions, including community colleges, with larger numbers of students in both corequisite and non-corequisite sections

State v. Brown: A Test for Local Food Ordinances

For many of us, adding a little milk to our morning coffee is likely one of the more insignificant tasks of the day. For Dan Brown of Blue Hill, Maine, that splash of dairy in his coffee mug is the result of his personal labor and constant, meticulous attention paid to the health and well-being of a single 1,000 pound mammal. Besides fresh raw milk, what does Brown gain from his efforts? He knows the exact source of the milk he puts in his coffee, as well as the butter his daughter spreads on her toast: Sprocket, Brown’s sole dairy cow. However, Sprocket has garnered Brown some wanted attention recently, earning her a new moniker: “Troublemaker.” Whatever dairy Sprocket produces that does not end up in Brown’s family’s coffee or cereal, Dan Brown offers for sale directly from his farm, Gravelwood Farm, or at local farmers’ markets in towns of Blue Hill and nearby Ellsworth. These sales, “which net Brown roughly $8, gained the attention of the Maine Department of Agriculture (“the Department”). The Department, noting that Brown was not properly licensed as either a milk distributor or food establishment, advised him that he was not in compliance with state law and demanded that he cease the sale of all food products until he complied with licensing requirements, or otherwise face legal action. Furthermore, having previously taken samples from Brown’s raw whole milk, butter, and cottage cheese, the Department claimed that his dairy products “failed to meet established standards for quality and safety,” and that Brown was “exposing consumers to serious health risks.” Despite these demands and threats of legal action, Brown continued to sell his food products without a Department license recognizing him as an authorized distributor or food establishment

Personal Jurisdiction in the Data Age: MacDermid v. Deiter\u27s Adaptation of International Shoe Amidst Supreme Court Uncertainty

In MacDermid, Inc. v. Deiter, the Second Circuit held that a Connecticut court may exercise personal jurisdiction over a defendant who allegedly used a computer in Canada to remotely access a computer server located in Connecticut in order to misappropriate proprietary, confidential electronic information belonging to a Connecticut corporation. This Note argues that, given the factual elements before the court, MacDermid was an unsurprising, orthodox, and proper holding in the context of personal jurisdiction jurisprudence. However, the facts in MacDermid, and the corresponding limits inherent in the Second Circuit’s holding, reveal potentially gaping holes in our modern personal jurisdiction framework and its ability to respond to the realities of modern commerce and technology