Depression’s Connection to Self-Harming Behavior in Adolescents

Self-harming behavior amongst adolescents has increased in prevalence throughout America. There is a direct connection between depression and self-harming behaviors in adolescent students. The most common reasons why adolescents participate in self-injury are as a coping mechanism, a means of relief, for the regulation of feelings, self-punishment, attention seeking and sensation seeking. There is often a link between depressive symptoms and negative life events or past trauma. Multiple methods of self-harm are often performed by students and may be carried out several times over the course of many months, the techniques used vary greatly. Schools are one of the most important institutions that are in a position to help-self injurers. In this paper I will look at the causes, effects and possible preventative methods of self-injurious behavior

Can Local Stress Enhancement Induce Stability in Fracture Processes? Part I: Apparent Stability

By comparing the evolution of the local and equal load sharing fiber bundle models, we point out the paradoxical result that stresses seem to make the local load sharing model stable when the equal load sharing model is not. We explain this behavior by demonstrating that it is only an apparent stability in the local load sharing model, which originates from a statistical effect due to sample averaging. Even though we use the fiber bundle model to demonstrate the apparent stability, we argue that it is a more general feature of fracture processes.Comment: 7 pages, 8 figure

Rancang Bangun Alat Deteksi Uang Kertas Palsu dengan Metode Template Matching Menggunakan Raspberry Pi

Cara manual yang digunakan untuk mendeteksi keaslian uang kertas memiliki banyak kelemahan. Oleh karena itu, pada penelitian ini dirancang sebuah alat yang dapat mengidentifikasi keaslian uang kertas tanpa mengandalkan penglihatan manusia. Sistem pada alat ini menggunakan mini PC Raspberry Pi, lampu ultraviolet, kamera dan metode Template Matching. Template Matching adalah sebuah teknik pada pengolahan citra digital untuk menemukan bagian-bagian kecil dari gambar yang cocok dengan gambar template. Lampu ultraviolet digunakan untuk memunculkan gambar Invisible Ink dari objek uang kertas pecahan 50.000. Kamera digunakan untuk menangkap gambar uang kertas setelah disinari lampu ultraviolet. Gambar tersebut kemudian diproses di Raspberry Pi menggunakan library OpenCV untuk mendapatkan nilai hasil kemiripan dengan gambar. Keluaran dari sistem ini berupa suara yang memberikan informasi tentang asli atau tidaknya uang kertas tersebut. Dari 16 kali percobaan dengan posisi kamera tetap dan berjarak + 8 cm dari uang, terdapat 2 kali kegagalan yang disebabkan tipisnya perbedaan warna dasar uang dengan gambar template, sehingga didapatkan tingkat keberhasilan sebesar 87,5%. Sedangkan pada jarak + 7 cm dan +6 cm dari uang kertas sistem tidak dapat mendeteksi keaslian uang kertas tersebut. Dari 25 kali percobaan berdasarkan posisi/kemiringan uang kertas didapatkan tingkat 36%. Oleh karena itu Template Matching sangat dipengaruhi oleh template, tresholding, posisi objek, serta posisi/jarak kamera

‘Black like Me’: A Critical Analysis of Arrest Practices Based on Skin Color in the Gauteng Province, South Africa

Objective: This article looks at the everyday life and realities of current practices employed by the South African Police Service (SAPS) officials, by shedding light on the experiences and practices on profiling search and effecting arrest based on race and skin color in the Gauteng Province. Particularly, this article examines the experiences of the SAPS officials to measure police perception of the skin color of foreign nationals, and to establish if wrongful arrests were linked to skin color stereotyping. Methods: The theoretical approach employed the social identity theory (SIT) was used to interpret the results. A survey questionnaire consisting of the New Immigration Survey (NIS) Skin Color Scale with 10 shades of skin color mapped to a pictorial guide, as well as a self-report measure on wrongful arrests, was administered to 80 SAPS officials, who performed visible policing duties. The research sample consisted of two SAPS groups from two different contexts, namely township and urban contexts. The Statistical Package for the Social Sciences (SPSS) software was used to conduct Pearson’s correlation and comparative analyses. Results: The results showed that the SAPS officials stereotyped foreign nationals as dark-skinned. The skin color stereotype was, however, not correlated to wrongful arrests. The study concluded that although respondents perceived that South Africans were distinguishable from foreign nationals based on skin color or tone, identification processes were not influenced by this stereotype belief

Multiple packets of neutral molecules revolving for over a mile

The level of control that one has over neutral molecules in beams dictates their possible applications. Here we experimentally demonstrate that state-selected, neutral molecules can be kept together in a few mm long packet for a distance of over one mile. This is accomplished in a circular arrangement of 40 straight electrostatic hexapoles through which the molecules propagate over 1000 times. Up to 19 packets of molecules have simultaneously been stored in this ring structure. This brings the realization of a molecular low-energy collider within reach

Dense, Fe-rich Ejecta in Supernova Remnants DEM L238 and DEM L249: A New Class of Type Ia Supernova?

We present observations of two LMC supernova remnants (SNRs), DEM L238 and DEM L249, with the Chandra and XMM-Newton X-ray satellites. Bright central emission, surrounded by a faint shell, is present in both remnants. The central emission has an entirely thermal spectrum dominated by strong Fe L-shell lines, with the deduced Fe abundance in excess of solar and not consistent with the LMC abundance. This Fe overabundance leads to the conclusion that DEM L238 and DEM L249 are remnants of thermonuclear (Type Ia) explosions. The shell emission originates in gas swept up and heated by the blast wave. A standard Sedov analysis implies about 50 solar masses in both swept-up shells, SNR ages between 10,000 and 15,000 yr, low (< 0.05 cm^-3) preshock densities, and subluminous explosions with energies of 3x10^50 ergs. The central Fe-rich supernova ejecta are close to collisional ionization equilibrium. Their presence is unexpected, because standard Type Ia SNR models predict faint ejecta emission with short ionization ages. Both SNRs belong to a previously unrecognized class of Type Ia SNRs characterized by bright interior emission. Denser than expected ejecta and/or a dense circumstellar medium around the progenitors are required to explain the presence of Fe-rich ejecta in these SNRs. Substantial amounts of circumstellar gas are more likely to be present in explosions of more massive Type Ia progenitors. DEM L238, DEM L249, and similar SNRs could be remnants of ``prompt'' Type Ia explosions with young (~100 Myr old) progenitors.Comment: 24 pages, 8 figures, ApJ, in pres

Molecular Cloning and Characterization of a Novel Mouse Macrophage C-type Lectin, mMGL2, Which Has a Distinct Carbohydrate Specificity from mMGL1

A novel mouse macrophage galactose-type C-type lectin 2 (mMGL2) was identified by BLAST analysis of expressed sequence tags. The sequence of mMGL2 is highly homologous to the mMGL, which should now be called mMGL1. The open reading frame of mMGL2 contains a sequence corresponding to a type II transmembrane protein with 332 amino acids having a single extracellular C-type lectin domain. The 3\u27-untranslated region included long terminal repeats of mouse early transposon. The Mgl2 gene was cloned from a 129/SvJ mouse genomic library and sequenced. The gene spans 7,136 base pairs and consists of 10 exons, which is similar to the genomic organization of mMGL1. The reverse transcriptase-PCR analysis indicates that mMGL2 is expressed in cell lines and normal mouse tissues in a macrophage-restricted manner, also very similar to that of mMGL1. The mMGL2 mRNA was also detected in mMGL1-positive cells, which were sorted from thioglycollate-induced peritoneal cells with a mMGL1-specific monoclonal antibody, LOM-8.7. The soluble recombinant proteins of mMGL2 exhibited carbohydrate specificity for alpha- and beta-GalNAc-conjugated soluble polyacrylamides, whereas mMGL1 preferentially bound Lewis X-conjugated soluble polyacrylamides in solid phase assays. These two lectins may function cooperatively as recognition and endocytic molecules on macrophages and related cells

Role of precombustion chamber design in feed-system coupled instabilities of hybrid rockets

Oxidizer feed-system coupled instabilities have been observed in several liquid and hybrid propellant rocket engines, although they are not likely to be catastrophic for the latter. However, severe pressure oscillation in hybrid rocket may result in a significant reduction in the performance of the propulsion system restricting the application of the technology. In this research, feed-system coupled instabilities were studied theoretically and experimentally for hybrid rocket engines. Two test campaigns were performed to investigate the effects of the precombustion chamber and oxidizer injector configurations on engine pressure oscillation. Then, an extended mathematical formulation (including the injector pressure drop, the precombustion chamber residence time, the gas residence time, and the combustion time lag) has been proposed. The investigation was based on a transfer function using the stability limit analysis and the root locus method. It has been found that the configuration of the precombustion chamber plays an important role in the nature of the feed-system coupled instabilities, and a correlation was proposed to predict the fundamental frequency based on the oxidizer precombustion chamber residence time. The work has shown that the precombustion chamber length and the oxidizer injection velocity are key parameters that affect the period of the pressure oscillations in hybrid engines subjected to feed-system coupled instabilities