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The Hmong are an ethnic group from Southeast Asia who has lived as forced political refugees for the past several hundred years. In the 1960s, the Central Intelligence Agency (CIA) recruited the Hmong to assist them with the Vietnam War. After the United States withdrew from the war, the Hmong were left behind and became the target to the Laotian and Vietnamese communists. This led to them experiencing traumatic events as they walked from Laos to Thailand to escape ethnic cleansing. From the refugee camps in Thailand to arriving in the United States, the Hmong have encountered various mental-health related issues. The purpose of this literature is to explore the mental-health seeking behaviors among the Hmong population and identify the common mental-health issues they encountered. Using a systematic review, a total of 27 articles were picked from PubMed and Hmong Studies Journal to be examined. This literature review found that the Hmong people have a low rate of seeking Western treatments because their community has always consulted a Hmong shaman, herbs or family members when they experience an illness. Findings also revealed common mental problems: depression, anxiety, adjustments issues, and other health concerns related to the work environment in a new country.

Poetry

Poetry

Nanoelectromechanical systems (NEMS) are microelectromechanical systems (MEMS) scaled down to nanometer range. As the size of the NEMS resonators is scaled downward, some fundamental and nonfundamental noise processes will impose sensitivity limits to their performance. In this work, we first present theory of phase noise mechanism of NEMS to examine both fundamental and nonfundamental noise processes. Fundamental noise processes considered here include thermomechanical noise, momentum-exchange noise, adsorption-desorption noise, diffusion noise, and temperature-fluctuation noise. For nonfundamental noise processes, we develop a formalism to consider the Nyquist-Johnson noise from transducer-amplifier implementations. As an initial step to experimental exploration of these noise processes, we describe and analyze several phase-locked loop schemes based on NEMS at very high frequency and ultrahigh frequency bands. In particular, we measure diffusion noise of NEMS arising from xenon atoms adsorbed on the device surface using the frequency modulation phase-locked loop. The observed spectra of fractional frequency noise and Allan deviation agree well with the prediction from diffusion noise theory. Finally, NEMS resonators also provide unprecedented sensitivity for inertial mass sensing. We demonstrate in situ measurement in real time with mass floor of ~20 zg. Our best mass sensitivity corresponds to ~7 zeptograms, equivalent to ~30 xenon atoms or the mass of an individual 4 kDa molecule. Detailed analysis of the ultimate sensitivity of such devices based on these experimental results indicates that NEMS can ultimately provide inertial mass sensing of individual intact, electrically neutral macromolecules with single-Dalton sensitivity.