艾叶香中寻玉佩

邹凤岭

    ①催春的雨，引得山茶流红，麦苗铺绿，湖色空蒙。湖岸被雨水浇出一片嫩绿，艾叶散发着清雅的香气。在这氤氲的艾香中，我又想起了儿时的情景。

    ②年幼的我跟在奶奶身后，走过村头的木桥：迎春花一片片，新生芦苇一丛丛。雨水打湿高高晾起的渔网，细细地流进湖里。我学着奶奶的样子，摘下一片嫩芽，仿佛闻到了那贴在锅里的艾饼的香甜。雨后积在艾叶上的水滴从指缝滑落，“滴答”声融入醒来的土地。

    ③沿着当年的田间小路，我又回到了老屋。老屋还是熟悉的模样，泥垒的墙、泥烧的瓦、泥砌的灶，连大门正面的照壁也是泥做的。老屋南墙上，树枝支起的窗棂与木板拼成的门楣上方，挂着菖蒲与艾条。窗棂下摆着老旧的石磨，这磨由上下两块尺寸相同的短圆形石块做成，磨拐是用门前大楝树的枝做成的，一端连接在上磨，一端用绳索系挂在灶房的横梁上。我仿佛又听到石磨“吱吱”转动的响声，看到奶奶教我磨面的身影。奶奶推动磨拐，石磨每转动一周，我就往磨眼里添加一小瓢碎米粒。随着石磨一圈圈转动，细面就落在了磨盘里。奶奶在面粉里加入焯过的艾叶，拌匀，做成小饼，贴在锅灶上。生起红红的灶火，慢慢地煎。随着木制锅盖下滴进铁锅的水溅声，热气带着那艾的香、面的甜，飘满村落。

    ④推开奶奶的房门，那个老旧的木箱子静静地守在屋角。触摸脱去桐油的边框，那些往事愈加清晰。

    ⑤那年新年，奶奶打开木箱子，从箱底下摸出簇新的一角纸币，又从门楣上撕下一片红喜纸，包裹好，放在我贴身衣袋里，是给我的压岁钱。就在打开木箱那一刻，我看到了一支黄亮亮的竹笛，红线系着颗玉心佩。听父亲说，竹笛是爷爷生前留下的，玉心佩是奶奶的奶奶传下来的。

    ⑥再见玉心佩是在那个灾荒年，在遭遇连续的自然灾害后，村里人食不果腹，野菜不够充饥，我再没闻见艾饼的香气。清明节前几天，我看见奶奶戴起那多年未戴的玉心佩，去了一趟老镇。回来后，变戏法似的做出了艾叶饼。我跟随奶奶去上坟，祭祀仪式毕，奶奶给了我一块小艾饼，将剩下的全都分给了跟来的孩子们。

    ⑦奶奶上了年纪后，眼睛已看不见，她常坐在门槛上静静地听雨。有一段日子，奶奶倚在床上，连门槛也少坐。雨细细地下，风轻轻地吹，门楣上枯艾和菖蒲呜呜作响，好似远处隐约传来的竹笛声。我瞧见奶奶脸上浮现出少有的红晕，伸出小手抚摸奶奶的脸。静静地，听见奶奶自言自语小声说：“好你个外人，又来到我面前吹那好听的竹笛。”

    ⑧那之后，奶奶再没下过床。母亲打开奶奶的旧木箱，我看到了那黄亮的竹笛，却不见了系在竹笛上的玉心佩。祖辈以农耕为生，奶奶一世清贫，养育子女多人已属不易。家里原本就没有什么值钱的东西，唯有玉心佩。母亲翻遍了木箱的底，也未找到玉心佩，赶紧走到床前，贴在奶奶耳边问：“娘，那玉心佩呢？”奶奶不言语。母亲说：“是要给您老人家带走的。”奶奶用微弱的声音说：“要走了，还带那东西做啥？”奶奶走了，终究没说玉心佩在哪里。

    ⑨走出房门，雨停了，我又闻到空气中飘来的艾叶的清香。

（选自《做人与处世》，有删改）

    Self-driving vehicles will rely on cameras, sensors and artificial intelligence (AI) to recognize and respond to road and traffic conditions, but sensing is the most effective for objects and movement in the neighborhood of the vehicle. Not everything important in a car's environment will be caught by the vehicle's camera. Another vehicle approaching at high speed on a collision (碰撞) track might not be visible until it's too late. This is why vehicle-to-vehicle communication is undergoing rapid development. Our research shows that cars will need to be able to chat and cooperate on the road, although the technical challenges are considerable.

    Applications for vehicle- to-vehicle communication range from vehicles driving together in a row, to safety messages about nearby emergency vehicles. Vehicles could alert each other to avoid collisions or share notices about passers-by and bicycles.

    From as far as several hundred meters away, vehicles could exchange messages with one another or receive information from roadside units (RSUs) about nearby incidents or dangerous road conditions through 4G network. A high level of AI seems required for such vehicles, not only to self-drive from A to B, but also to react intelligently to messages received. Vehicles will need to plan, reason, strategize and adapt in the light of information received in real time and to carry out cooperative behaviors. For example, a group of autonomous vehicles might avoid a route together because of potential risks, or a vehicle could decide to drop someone off earlier due to messages received, a foreseen crowding ahead.

    Further applications of vehicle- to-vehicle communication are still being researched, including how to perform cooperative behavior.

我国首部慈善法——《中华人民共和国慈善法》的产生过程如下：

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