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<informationTable xmlns="http://www.sec.gov/edgar/document/thirteenf/informationtable" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
<infoTable><nameOfIssuer>AXT INC</nameOfIssuer><titleOfClass>COM</titleOfClass><cusip>00246W103</cusip><value>190</value><shrsOrPrnAmt><sshPrnamt>43900</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><votingAuthority><Sole>0</Sole><Shared>0</Shared><None>43900</None></votingAuthority></infoTable>
<infoTable><nameOfIssuer>BANK OZK</nameOfIssuer><titleOfClass>COM</titleOfClass><cusip>06417N103</cusip><value>588</value><shrsOrPrnAmt><sshPrnamt>25790</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><votingAuthority><Sole>0</Sole><Shared>0</Shared><None>25790</None></votingAuthority></infoTable>
<infoTable><nameOfIssuer>BROOKFIELD ASSET MGMT INC</nameOfIssuer><titleOfClass>CL A LTD VT SH</titleOfClass><cusip>112585104</cusip><value>1201</value><shrsOrPrnAmt><sshPrnamt>31337</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><votingAuthority><Sole>0</Sole><Shared>0</Shared><None>31337</None></votingAuthority></infoTable>
<infoTable><nameOfIssuer>CHARTER COMMUNICATIONS INC N</nameOfIssuer><titleOfClass>CL A</titleOfClass><cusip>16119P108</cusip><value>1517</value><shrsOrPrnAmt><sshPrnamt>5326</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><votingAuthority><Sole>0</Sole><Shared>0</Shared><None>5326</None></votingAuthority></infoTable>
<infoTable><nameOfIssuer>DISH NETWORK CORP</nameOfIssuer><titleOfClass>CL A</titleOfClass><cusip>25470M109</cusip><value>834</value><shrsOrPrnAmt><sshPrnamt>33417</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><votingAuthority><Sole>0</Sole><Shared>0</Shared><None>33417</None></votingAuthority></infoTable>
<infoTable><nameOfIssuer>DORCHESTER MINERALS LP</nameOfIssuer><titleOfClass>COM UNIT</titleOfClass><cusip>25820R105</cusip><value>5442</value><shrsOrPrnAmt><sshPrnamt>371762</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><votingAuthority><Sole>0</Sole><Shared>0</Shared><None>371762</None></votingAuthority></infoTable>
<infoTable><nameOfIssuer>DOWDUPONT INC</nameOfIssuer><titleOfClass>COM</titleOfClass><cusip>26078J100</cusip><value>208</value><shrsOrPrnAmt><sshPrnamt>3898</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><votingAuthority><Sole>0</Sole><Shared>0</Shared><None>3898</None></votingAuthority></infoTable>
<infoTable><nameOfIssuer>ECHOSTAR CORP</nameOfIssuer><titleOfClass>CL A</titleOfClass><cusip>278768106</cusip><value>374</value><shrsOrPrnAmt><sshPrnamt>10193</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><votingAuthority><Sole>0</Sole><Shared>0</Shared><None>10193</None></votingAuthority></infoTable>
<infoTable><nameOfIssuer>EXXON MOBIL CORP</nameOfIssuer><titleOfClass>COM</titleOfClass><cusip>30231G102</cusip><value>497</value><shrsOrPrnAmt><sshPrnamt>7303</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><votingAuthority><Sole>0</Sole><Shared>0</Shared><None>7303</None></votingAuthority></infoTable>
<infoTable><nameOfIssuer>FACEBOOK INC</nameOfIssuer><titleOfClass>CL A</titleOfClass><cusip>30303M102</cusip><value>800</value><shrsOrPrnAmt><sshPrnamt>6107</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><votingAuthority><Sole>0</Sole><Shared>0</Shared><None>6107</None></votingAuthority></infoTable>
<infoTable><nameOfIssuer>FORTINET INC</nameOfIssuer><titleOfClass>COM</titleOfClass><cusip>34959E109</cusip><value>563</value><shrsOrPrnAmt><sshPrnamt>8000</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><votingAuthority><Sole>0</Sole><Shared>0</Shared><None>8000</None></votingAuthority></infoTable>
<infoTable><nameOfIssuer>ISHARES TR</nameOfIssuer><titleOfClass>CORE S&amp;P500 ETF</titleOfClass><cusip>464287200</cusip><value>68669</value><shrsOrPrnAmt><sshPrnamt>272921</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><votingAuthority><Sole>0</Sole><Shared>0</Shared><None>272921</None></votingAuthority></infoTable>
<infoTable><nameOfIssuer>ISHARES TR</nameOfIssuer><titleOfClass>RUS 2000 GRW ETF</titleOfClass><cusip>464287648</cusip><value>413</value><shrsOrPrnAmt><sshPrnamt>2459</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><votingAuthority><Sole>0</Sole><Shared>0</Shared><None>2459</None></votingAuthority></infoTable>
<infoTable><nameOfIssuer>ISHARES TR</nameOfIssuer><titleOfClass>S&amp;P 500 GRWT ETF</titleOfClass><cusip>464287309</cusip><value>447</value><shrsOrPrnAmt><sshPrnamt>2973</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><votingAuthority><Sole>0</Sole><Shared>0</Shared><None>2973</None></votingAuthority></infoTable>
<infoTable><nameOfIssuer>ISHARES TR</nameOfIssuer><titleOfClass>RUS 1000 ETF</titleOfClass><cusip>464287622</cusip><value>519</value><shrsOrPrnAmt><sshPrnamt>3748</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><votingAuthority><Sole>0</Sole><Shared>0</Shared><None>3748</None></votingAuthority></infoTable>
<infoTable><nameOfIssuer>ISHARES TR</nameOfIssuer><titleOfClass>MSCI EAFE ETF</titleOfClass><cusip>464287465</cusip><value>231</value><shrsOrPrnAmt><sshPrnamt>3933</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><votingAuthority><Sole>0</Sole><Shared>0</Shared><None>3933</None></votingAuthority></infoTable>
<infoTable><nameOfIssuer>ISHARES TR</nameOfIssuer><titleOfClass>1 3 YR TREAS BD</titleOfClass><cusip>464287457</cusip><value>1440</value><shrsOrPrnAmt><sshPrnamt>17232</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><votingAuthority><Sole>0</Sole><Shared>0</Shared><None>17231</None></votingAuthority></infoTable>
<infoTable><nameOfIssuer>ISHARES TR</nameOfIssuer><titleOfClass>SHORT TREAS BD</titleOfClass><cusip>464288679</cusip><value>777</value><shrsOrPrnAmt><sshPrnamt>7047</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><votingAuthority><Sole>0</Sole><Shared>0</Shared><None>7047</None></votingAuthority></infoTable>
<infoTable><nameOfIssuer>KINDER MORGAN INC DEL</nameOfIssuer><titleOfClass>COM</titleOfClass><cusip>49456B101</cusip><value>3260</value><shrsOrPrnAmt><sshPrnamt>212024</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><votingAuthority><Sole>0</Sole><Shared>0</Shared><None>212024</None></votingAuthority></infoTable>
<infoTable><nameOfIssuer>LIBERTY GLOBAL PLC</nameOfIssuer><titleOfClass>SHS CL C</titleOfClass><cusip>G5480U120</cusip><value>566</value><shrsOrPrnAmt><sshPrnamt>27463</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><votingAuthority><Sole>0</Sole><Shared>0</Shared><None>27463</None></votingAuthority></infoTable>
<infoTable><nameOfIssuer>LIBERTY LATIN AMERICA LTD</nameOfIssuer><titleOfClass>COM CL C</titleOfClass><cusip>G9001E128</cusip><value>526</value><shrsOrPrnAmt><sshPrnamt>36143</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><votingAuthority><Sole>0</Sole><Shared>0</Shared><None>36143</None></votingAuthority></infoTable>
<infoTable><nameOfIssuer>MAGELLAN MIDSTREAM PRTNRS LP</nameOfIssuer><titleOfClass>COM UNIT RP LP</titleOfClass><cusip>559080106</cusip><value>1693</value><shrsOrPrnAmt><sshPrnamt>29683</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><votingAuthority><Sole>0</Sole><Shared>0</Shared><None>29683</None></votingAuthority></infoTable>
<infoTable><nameOfIssuer>MERCK &amp; CO INC</nameOfIssuer><titleOfClass>COM</titleOfClass><cusip>58933Y105</cusip><value>228</value><shrsOrPrnAmt><sshPrnamt>2986</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><votingAuthority><Sole>0</Sole><Shared>0</Shared><None>2986</None></votingAuthority></infoTable>
<infoTable><nameOfIssuer>NEXSTAR MEDIA GROUP INC</nameOfIssuer><titleOfClass>CL A</titleOfClass><cusip>65336K103</cusip><value>740</value><shrsOrPrnAmt><sshPrnamt>9415</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><votingAuthority><Sole>0</Sole><Shared>0</Shared><None>9415</None></votingAuthority></infoTable>
<infoTable><nameOfIssuer>PNC FINL SVCS GROUP INC</nameOfIssuer><titleOfClass>COM</titleOfClass><cusip>693475105</cusip><value>350</value><shrsOrPrnAmt><sshPrnamt>3000</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><votingAuthority><Sole>0</Sole><Shared>0</Shared><None>3000</None></votingAuthority></infoTable>
<infoTable><nameOfIssuer>POST HLDGS INC</nameOfIssuer><titleOfClass>COM</titleOfClass><cusip>737446104</cusip><value>1239</value><shrsOrPrnAmt><sshPrnamt>13904</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><votingAuthority><Sole>0</Sole><Shared>0</Shared><None>13904</None></votingAuthority></infoTable>
<infoTable><nameOfIssuer>SELECT SECTOR SPDR TR</nameOfIssuer><titleOfClass>TECHNOLOGY</titleOfClass><cusip>81369Y803</cusip><value>207</value><shrsOrPrnAmt><sshPrnamt>3345</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><votingAuthority><Sole>0</Sole><Shared>0</Shared><None>3345</None></votingAuthority></infoTable>
<infoTable><nameOfIssuer>SPDR S&amp;P 500 ETF TR</nameOfIssuer><titleOfClass>TR UNIT</titleOfClass><cusip>78462F103</cusip><value>293</value><shrsOrPrnAmt><sshPrnamt>1176</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><votingAuthority><Sole>0</Sole><Shared>0</Shared><None>1176</None></votingAuthority></infoTable>
<infoTable><nameOfIssuer>SUNCOR ENERGY INC NEW</nameOfIssuer><titleOfClass>COM</titleOfClass><cusip>867224107</cusip><value>560</value><shrsOrPrnAmt><sshPrnamt>20030</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><votingAuthority><Sole>0</Sole><Shared>0</Shared><None>20030</None></votingAuthority></infoTable>
<infoTable><nameOfIssuer>TEAM INC</nameOfIssuer><titleOfClass>COM</titleOfClass><cusip>878155100</cusip><value>157</value><shrsOrPrnAmt><sshPrnamt>10750</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><votingAuthority><Sole>0</Sole><Shared>0</Shared><None>10750</None></votingAuthority></infoTable>
<infoTable><nameOfIssuer>TRANSDIGM GROUP INC</nameOfIssuer><titleOfClass>COM</titleOfClass><cusip>893641100</cusip><value>7122</value><shrsOrPrnAmt><sshPrnamt>20944</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><votingAuthority><Sole>0</Sole><Shared>0</Shared><None>20944</None></votingAuthority></infoTable>
<infoTable><nameOfIssuer>VANGUARD SCOTTSDALE FDS</nameOfIssuer><titleOfClass>SHORT TERM TREAS</titleOfClass><cusip>92206C102</cusip><value>3472</value><shrsOrPrnAmt><sshPrnamt>57753</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><votingAuthority><Sole>0</Sole><Shared>0</Shared><None>57753</None></votingAuthority></infoTable>
<infoTable><nameOfIssuer>VANGUARD SCOTTSDALE FDS</nameOfIssuer><titleOfClass>SHRT TRM CORP BD</titleOfClass><cusip>92206C409</cusip><value>201</value><shrsOrPrnAmt><sshPrnamt>2581</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><votingAuthority><Sole>0</Sole><Shared>0</Shared><None>2581</None></votingAuthority></infoTable>
<infoTable><nameOfIssuer>VANGUARD STAR FD</nameOfIssuer><titleOfClass>VG TL INTL STK F</titleOfClass><cusip>921909768</cusip><value>225</value><shrsOrPrnAmt><sshPrnamt>4769</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><votingAuthority><Sole>0</Sole><Shared>0</Shared><None>4769</None></votingAuthority></infoTable>
<infoTable><nameOfIssuer>VERIZON COMMUNICATIONS INC</nameOfIssuer><titleOfClass>COM</titleOfClass><cusip>92343V104</cusip><value>252</value><shrsOrPrnAmt><sshPrnamt>4484</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><votingAuthority><Sole>0</Sole><Shared>0</Shared><None>4484</None></votingAuthority></infoTable>
</informationTable>
