Given a context passage, generate a question from the passage such that its answer is shortest continous span from the passage.

Tumors of the nervous system most often occur in both children and adults as sporadic events with no family history of the disease, but they are also among the clinical manifestations of a significant number of familial cancer syndromes, including familial retinoblastoma, neurofibromatosis 1 and 2, tuberous sclerosis, and Cowden, Turcot, Li-Fraumeni and nevoid basal cell carcinoma (Gorlin) syndromes. All of these syndromes involve transmissible genetic risk resulting from loss of a functional allele, or inheritance of a structurally defective allele, of a specific gene. These genes include RB1, NF1, NF2, TSC1, TSC2, TP53, PTEN, APC, hMLH1, hPSM2, and PTCH, most of which function as tumor suppressor genes. The same genes are also observed in mutated and inactive forms, or are deleted, in tumor cells in sporadic cases of the same tumors. The nature of the mutational events that give rise to these inactivated alleles suggests a possible role of environmental mutagens in their causation. However, only external ionizing radiation at high doses is clearly established as an environmental cause of brain, nerve and meningeal tumors in humans. Transplacental carcinogenesis studies in rodents and other species emphasize the extraordinary susceptibility of the developing mammalian nervous system to carcinogenesis, but the inverse relationship of latency to dose suggests that low transplacental exposures to genotoxicants are more likely to result in brain tumors late in life, rather than in childhood. While not all neurogenic tumor-related genes in humans have similar effects in experimental rodents, genetically engineered mice (GEM) increasingly provide useful insights into the combined effects of multiple tumor suppressor genes and of gene-environment interactions in the genesis of brain tumors, especially pediatric brain tumors such as medulloblastoma.
Which is the gene mutated in type 1 neurofibromatosis?

Hello, Listeners. Welcome to Henton Hospital Radio. Before our music programme at four, I'm going to repeat some of our hospital rules. The hospital can sleep 800 patients. There're 8 beds in each ward . The visiting hours are in the afternoon from 2:30 to 3:30 and in the evening from 7:00 to 8:00. But remember only two people can see you at the same time. Sorry about that, but you can see what would happen if we didn't have these rules. The other rules are about our hours. We start quite early---you might not be used to that. We wake you at 6 o'clock, and breakfast is at 8 o'clock, lunch is at noon. There's tea at 3:30 and supper is at 6 o'clock. You can see the non-smoking sign---we don't allow smoking in the wards. I'm sure you understand why. However, if you do need to smoke, there are some smoking rooms where it is allowed. You will find the radio switch on the wall near your bed, with your own headphones, if you want to listen. It's our own hospital radio wishing you a quick recovery.
Who do you think the listeners might be?

Si Renfa's son Si Jifa escaped and continued independent action in another corner of southwest Yunnan. He sent his younger brother Zhaosai to seek pardon from Ming while at the same time he attacked Ming troops in early 1443. However they were defeated and he was forced to flee to Mong Yang. Zhaosai was kept as a hostage and the Ming retreated from Mong Mao. Seeing that Mong Mao was no longer occupied, Si Jifa returned to his father's base of power and began attacking neighboring tribes once again. The third punitive expedition was led by Wang Ji and launched in March 1443. Although the mission was to capture Si Jifa, negotiations on the return of Si Renfa had fallen ill. Ava demanded Ming territory for itself and Hsenwi in return of Si Renfa. Furthermore Ava had made peace with Si Jifa. Therefore, although the Ming army quickly defeated Si Jifa's base of power and captured his family, Si Jifa managed to escape to Mong Yang, and the Ming army decided not to pursue out of consideration of a combined Ava-Hsenwi attack on Ming forces. A compromise was finally reached between Ava and Ming in April 1445. Ava agreed to hand over Si Renfa in return for Ming support in annexing part of Hsenwi's territory. Si Renfa came into Ming custody in August 1445 and was executed in January 1446.

Who attacked Min troops in early 1443?