4 research outputs found

    大鼠氣道負壓對上呼吸道運動神經活動之影響

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    [[abstract]]To study the effect of changes in airway pressure on upper airway motor nerve activities, adult rats of Wistar were used. The rat was anesthetized with urethane, paralyzed, and artificially ventilated. Catheterization was performed in the trachea, femoral artery and vein. The phrenic, recurrent laryngeal (RLN), and hypoglossal nerves, as well as the abducent (Abd) and adducent (Add) branches of the RLN were separated and their activities were recorded under normocapnia in hyperoxia. The outlet of the ventilator was placed under water surface with a deep of 3 cm such that a 3-cmH2O positive end-expired pressure (PEEP) was obtained to be used as the control. The airway pressure measured by the tracheal pressure (TP) was decreased to a level of continuous negative airway pressure (CNAP) and of negative end-expired pressure (NEEP) at -1 and -3 cmH2O with a water trap system, and then increased to PEEP at 6 cmH2O. The observed results showed that blood pressure and respiratory frequency were increased, and phrenic burst was not changed in immediate response to CNAP and PEEP, and that activity of the entire RLN was significantly increased during inspiratory and expiratory period. Data from the recording of the intralaryngeal branches showed that activity of the Add RLN was increased and also extended to the inspiratory duration such that it transformed into a tonic discharge pattern with CNAP and NEEP. Activity of the hypoglossal nerve was significantly and immediately decreased with CNAP and NEEP. Increase in PEEP at 6 cmH2O produced a decrease of blood pressure and respiratory frequency without conspicuous change in phrenic burst. Activity of the Add RLN and Abd RLN was decreased. There was no change in hypoglossal activity but displayed an advancement in onset. All these reflexive responses were totally abolished after bilateral vagotomy. These results showed that airway resistance may be increased due to the increase of activity of the Add RLN and the decrease of hypoglossal discharge and that this increase in airway resistance may benefit for the maintenance of lung volume.

    The economic analysis of Taiwan''s rice support policy

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    台灣歷年來之農業政策皆以稻米政策為主,為穩定糧食生產及保障農民所得,政府採取保價收購政策、水旱田利用調整計畫等稻米支持政策,以達到維護農民權益、糧食安全等政策目標。 由於目前我國稻米政策大多直接影響土地,所以過去文獻大多探討相關政策對土地要素市場之影響,對其他要素市場之探討相對較少,因此本研究欲利用OECD發展之政策評估矩陣(PEM)模型,其作物市場與要素市場之連動關係,透過土地與其他要素,如農藥、肥料之替代關係,對國內農業支持政策,如保價收購、肥料補貼、對地補貼、價差給付等措施進行比較分析,以探討各支持政策對各變數,如國內產出、市場價格、土地、肥料與農藥等要素投入、農民所得、環境污染等造成之影響,進而作為評比各項政策工具抉擇之依據。 本文之研究結果整理如下:.在本研究的假設前提下,可得要素間之替代彈性、成本份額、供給彈性與作物需求彈性之大小,會影響各支持政策對各經濟變數之變動。.實施對地給付、肥料補貼與休耕政策對各要素市場之影響,與要素替代彈性及作物需求彈性的大小有關。若要素替代彈性小於作物需求彈性絕對值,則其他要素之價格與使用量會有減少之趨勢;反之,若要素間之替代程度高,則對其他要素之需求可能會有不減反增之現象。.在政府財政支出總額相同之前提下,保價收購政策與價差給付政策其生產效果較大,在全球糧食短缺、糧食價格飆漲之局勢下,為可讓政府有效充分掌握糧源、穩定糧價,進而達成維護糧食安全之政策。.在政府財政支出總額相同之前提下,價差給付政策對各要素市場之影響最大,其次是保價收購政策。對地給付政策、休耕給付政策與肥料補貼政策對各要素市場之影響則視支持政策主要補貼之對象而定。.在政府財政支出總額相同之前提下,價差給付政策其環境效果較差,其次是保價收購政策、肥料補貼政策,這些支持政策之實施皆會造成單位面積農化資材密集度增加,增加對環境之壓迫。至於土地給付政策其環境效果較佳,為維護環境上較有效率之政策。.休耕給付政策與對地給付政策補貼之對象皆為農民擁有之土地,因此該政策可將給付最有效率地轉移至農民所得上,所得效果相較其他政策大,其次是價差給付政策、保價收購政策。.要素補貼政策之所得效果,則視投入要素為自有或購買的而定,若投入要素為農民自有的,則對農民造成之所得效果相對較大,如對地給付政策,若投入要素為購買的,則該給付大部分會轉移至要素供給者,因此對農民造成之所得效果最小,如肥料補貼政策對農民之所得效果較小,對肥料供應者之所得效果較大。 農業政策之實施不只會影響到稻米作物之價格與產量,進而影響農民所得,亦或透過與要素市場之連結、要素間之替代關係影響肥料、農藥要素之使用,進而影響人體健康與生態環境。因此未來農業支持政策之研擬除了考量農民權益之維護、糧食安全及符合國際規範外,更應重視各政策對要素市場之影響,了解政策之補貼是否會造成肥料與農藥之過度使用,進而對生態環境造成無法彌補之傷害。第一章 緒論1一節 研究背景與動機1二節 研究目的與資料來源4二章 台灣稻作生產結構與政策演變6一節 台灣稻作概況6二節 台灣稻米政策之演變11三章 農業補貼政策及其相關之國際規範31一節 國內重要之農業補貼政策31二節 WTO農業協定對境內支持之規範36三節 OECD對農業支持政策之分類45四章 文獻回顧50一節 台灣稻米支持政策相關文獻50二節 世界各國農業支持政策相關文獻57五章 理論模型63一節 農業支持政策之圖形分析63二節 農業支持政策之經濟模型70三節 多投入下農業支持政策之經濟模型91六章 稻米支持政策之實證分析101一節 各支持政策對各經濟變數影響效果104二節 各支持政策之比較分析 114七章 結論與建議 117錄121考文獻 12
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