Gallium nitride (GaN) devices as a platform technology for radiation hard inertial confinement fusion diagnostics

Inertial Confinement Fusion (ICF) is undergoing more detailed research to increase neutron yield and will require high resolution imaging near the target. Neutron damage to diagnostics remains a serious issue in understanding and achieving ICF. We have demonstrated that Gallium Nitride (GaN) optoelectronic devices have exceptional neutron radiation hardness, by systematic testing of neutron radiation effects in GaN devices and materials with elevated neutron fluence levels and a broad neutron energy spectrum. During the 2013-2017 run cycles at Los Alamos Neutron Science Center (LANSCE), we irradiated various GaN materials and devices with fast and thermal plus resonance neutrons at several beamlines. This paper presents a radiation hardness study for Aluminum Gallium Nitride and Gallium Nitride (AlGaN/GaN) deep UV LEDs irradiated at the LANSCE 4FP60R beamline. The fluence level was up to 2.4 × 10¹³ neutrons/cm² for neutrons with energies greater than 0.1 MeV. The device performance was monitored in real time. After three years of irradiation studies, we found that the GaN devices maintained operation in the forward active region. The current and voltage relation (I-V curves) varied insignificantly in the linear region. Our results demonstrate the radiation hardness needed for laser fusion diagnostics at least up to 10¹⁷ neutron yield per shot, if the diagnostics is placed 1 m away from the target, where the neutron fluence per shot is approximately 8 × 10¹¹ n/cm². The GaN devices can operate for multiple shots.

The genome sequencing of an albino Western lowland gorilla reveals inbreeding in the wild

Background

The only known albino gorilla, named Snowflake, was a male wild born individual from Equatorial Guinea who lived at the Barcelona Zoo for almost 40 years. He was diagnosed with non-syndromic oculocutaneous albinism, i.e. white hair, light eyes, pink skin, photophobia and reduced visual acuity. Despite previous efforts to explain the genetic cause, this is still unknown. Here, we study the genetic cause of his albinism and making use of whole genome sequencing data we find a higher inbreeding coefficient compared to other gorillas.

Results

We successfully identified the causal genetic variant for Snowflake’s albinism, a non-synonymous single nucleotide variant located in a transmembrane region of SLC45A2. This transporter is known to be involved in oculocutaneous albinism type 4 (OCA4) in humans. We provide experimental evidence that shows that this amino acid replacement alters the membrane spanning capability of this transmembrane region. Finally, we provide a comprehensive study of genome-wide patterns of autozygogosity revealing that Snowflake’s parents were related, being this the first report of inbreeding in a wild born Western lowland gorilla.

Conclusions

In this study we demonstrate how the use of whole genome sequencing can be extended to link genotype and phenotype in non-model organisms and it can be a powerful tool in conservation genetics (e.g., inbreeding and genetic diversity) with the expected decrease in sequencing cost.

Information Program About Organ and Tissue Transplant-Donation Process at the Secondary Schools in the Province of Girona (Spain)

We believe that it is important to spread information about the organ and tissue transplant-donation (T-D) process to obtain the participation of all society. We prepared an information program about the T-D process for secondary school students in collaboration with the Education Department. We chose these students because they wish to receive information about life and are already conscious about its possible loss, and because they take risks practicing sports or driving cars. We spoke about the frequency of the T-D process in our hospitals, the organs and tissues that can be transplanted the number of people on the waiting list, as well as the origin and circumstances of potential donors. During the last 3 years we have done more than 200 lessons at 44 secondary schools. We consider our experience to be pleasant and useful. Students have accepted us and 96.5% of them have recommended the T-D lessons to future classmates.

An assistive home care environment for people with special needs

We have developed a system for supporting people with special needs. It allows remote monitoring of electrocardiographic and other signals together with multimode environmental control. The multimodal approach allows users with disabilities to interact more with the home environment. Telemedicine devices were integrated into the system to provide a link to health services. The system provided support for the independent living of people with special needs. The pilot site was a rehabilitation service attached to the National Paraplegic Hospital of Toledo, Spain. During the six-week trial period, the system did not fail, nor was any unauthorized access reported. Twelve people with special needs and three staff evaluated aspects of the system on a scale from 0 to 9, on which higher scores indicated a positive assessment. The mean score for efficiency was 7.8, for satisfaction 8, for helpfulness 7.4, for controllability 7.2 and for learnability 8.

Familial IgA nephropathy: report of two cases and brief review of the literature

Immunoglobulin A nephropathy developed in two siblings who shared the DRw4 antigen but who were otherwise HLA-A, -B, and -C unrelated. It is suggested that a genetically induced alteration in the immune response can cause some of the cases of mesangial IgA glomerulopathy and that close blood reltaives of patients with this disease should be checked for the possible existence of renal abnormalities.