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Objective The current global COVID-19 pandemic has disrupted supply chains and the production of essential goods and services. This includes personal protective equipment (PPE) kits, respirators, and other protective devices. Hence efforts were made to prototype and produce 3D-printed N95 respirators to fill the gap in supply. In addition, methods of sterilization were put into place for the respirators. As well as forming standard operating procedures. Methods With the use of vast open-source libraries and collaboration with engineers and doctors fighting the COVID-19 pandemic, respirator prototypes were produced with special consideration to the sizing to fit median facial sizes. Polymer plastics were mixed in various proportions to condition the respirator to be used by frontline workers in austere environments. Due to the shortage of medical-grade filter media, alternative sources were researched. Merv 13 and Merv 15 filters were selected due to their cheap costs, vast abundance, and proven filtration efficacy against particles of 0.03 microns. Studies conducted around the world have also shown its efficacy as an alternative to medical-grade air filter media. After developing standard operating procedures (SOPs) for sterilisation and respirator usage. Emergency approval was obtained and a limited number of healthcare workers were issued with this respirator (n=400). PPE kit satisfaction and self-efficacy scores were calculated from daily questionnaires during donning and doffing Results Qualitative fit-tests in all 400 healthcare workers matched those of a conventional N95 respirator. Almost all of the respondents in the PPE kit satisfaction responded positively. The self-efficacy score calculated from the general self-efficiency scale had an overall positive value, with the average score being 4.29. This demonstrated that the self-efficacy score was above average and indicated a high motivation to overcome obstacles and spend more time solving problems. The average self-efficacy score is defined between 2.5 - 3.5, and a low self-efficacy score is defined as a score below 2.5. Lastly, a regression analysis was done to test the correlation between PPE kit satisfaction and self-efficiency this demonstrated a positive correlation between PPE kit satisfaction using the 3D-printed respirator and self-efficacy (Slope: 0.416, Intercept: -1.066, R-value: 0.872, P-value

The purpose of this investigation is establish eleven year variation in cosmic ray intensity particularly in third harmonic after using cosmic ray intensity neutron monitor data on sixty quiet days. It has been observed that in spite of abrupt variation in amplitude and phase of third harmonic of cosmic ray intensity, the amplitude of third harmonic is relatively larger during the declining phase of solar cycle twenty one as it is observed during the declining phase of earlier solar cycle twenty. Therefore, this enhancement establishes the eleven year variation in third harmonic of cosmic ray intensity on quiet days at equatorial neutron monitoring stations. Further, no systemic change have been noticed in the amplitude and phase of fourth harmonics of cosmic ray intensity on quiet days, but the amplitude of fourth harmonic during the year 1981 and 1991 having the same value at equatorial neutron monitoring stations.

A large Forbush decrease (Fd) has been recorded by Moscow neutron monitoring station on 17th July 2017. An attempt has been made to understand the probable causes which have contributed for the occurrence of the large Fd. During the period of investigation extreme solar and interplanetary events i.e. sun spot numbers, disturbance storm time (Dst) index and Ap index has been investigated. The Dst index is suddenly increased during the event period indicating high geomagnetic activity during event time. The rise in sun spot numbers earlier the onset of forbush decrease reveals that it should have some connection with the occurrence of solar flares which further effects the cosmic ray variation. Probably this decrease is a result of high activity on the sun. The forbush decrease under investigation is probably due to the solar flare generated shock wave magnetic perturbation.

In order to perform the study of cosmic ray long-term modulation, we have used six monthly averaged cosmic ray data from Oulu (Rc = 0.78GV) and Rome (Rc = 6.32GV) neutron monitoring stations for three solar cycles. ( 21 - 23 ) with solar activity index (sunspot numbers). The detailed analysis of hysteresis effect between these two parameters has been done. The area of hysteresis loops and time lag with correlation coefficient between cosmic ray intensity and sunspot numbers have also been calculated and noticeable differences have been found during odd and even number solar cycles. Area of odd cycle loops is much larger than even cycle loop. Each hysteresis loop consists of a small secondary loop near solar maxima. Time lag between cosmic ray intensity and sunspot numbers is different in odd and even cycles. Implication and consequences of observed differences have been discussed in this paper.

Coronal mass ejections (CMEs) hurl huge volumes of magnetized plasma into interplanetary space often referred to as ICMEs or ejecta. They are an important component of solar wind and can cause enhanced geomagnetic activity when they interact with the Earth’s magnetosphere. When the ejecta have an average speed greater than the upstream solar wind speed they create a shock. The large IMF variations due to interplanetary shocks cause depression in the cosmic ray intensity (CRI) called Forbush Decrease (FD). Large FDs caused by fast CMEs are specifically associated with energetic X-ray flares. In the present paper, the author has studied seven largest Forbush decrease events selected from Moscow Neutron Monitor Station during a period of twelve years (1996-2008), i.e., 23rd solar cycle. The analysis of CRI data with interplanetary magnetic field |B|, its southward component Bz, solar wind velocity, Kp and Dst indices shows that all the three phenomena- solar, interplanetary and geomagnetic are connected to FD. The relationship between interplanetary parameters and FDs is discussed in detail. Moreover the solar cycle effect is found to be slightly shifted for large FDs as the frequency of occurrence of major FD events is more in the descending phase of the solar cycle.