關於 extrinsic factor ，我們在網路上蒐集到這些相關的討論、資訊與評價

凝血反應---複習專欄

凝血路徑
血管受傷害時，經由血塊凝集，形成止血作用。凝血反應路徑可分為以下3種：
1. 外在路徑(extrinsic pathway)：是對組織受損的反應。
2. 內在路徑(intrinsic pathway)：是對血管壁受損的反應。
3. 共同路徑(Common Pathway)：內在路徑與外在路徑共同使用的路徑
【外在】：因為反應需要血管以外的成份，即組織因子(tissue factor)；
【內在】：因為反應所需要的成份都存在於血管血液裡。

外在路徑在控制體內的凝血反應佔著比較重要的角色；它的啟動是組織受傷後，透過血管外產生組織因子(tissue factor)，然後與因子(Factor) 7, 10, 5, 2, 1產生連串反應。因此經常是在血管受傷之後，出血量較大的情況下啟動。它的路徑也比較短，因此活化時間也比較短，依序為：Factor 7, 10, 5, 2, 1。
先與第7凝血因子(Factor VII)結合，活化成Factor VIIa。基本上，外在路徑只走到這裡而已。
下面就與內在路徑一起進入共同路徑(Common Pathway)。

內在凝血路徑最終目標是形成活化的第10凝血因子(Xa)。內在路徑源自於第12凝血因子(又稱Hageman因子)，與高分子量之HMWK (High molecule weight kallikrein)、前動素原 (prekallikrein) 等複雜的效應，需要較多的因子才能啟動，因此活化的時間也比較慢。依序活化的順序為：Factors: 12, 11, 9, 8, 10, 5, 2 (Thrombin，凝血酶) 1 (Fibrin, 纖維蛋白)。

由上面說明，我們可以發現內、外凝血路徑中，Factors 10, 5, 2, 1是兩個路徑都會用到的，所以10, 5, 2, 1 的這段，又稱為共同路徑(Common Pathway) 。

繼續閱讀～～

- Luyện Reading, tìm từ vựng hay

MOTIVATIONAL FACTORS AND THE HOSPITALITY INDUSTRY

A critical ingredient in the success of hotels is developing and maintaining superior performance from their employees. How is that accomplished? What Human Resource Management (HRM) practices should organizations invest in to acquire and retain great employees?

Some hotels aim to provide superior working conditions for their employees. The idea originated from workplaces - usually in the non-service sector - that emphasized fun and enjoyment as part of work-life balance. By contrast, the service sector, and more specifically hotels, has traditionally not extended these practices to address basic employee needs, such as good working conditions.

Pfeffer (1994) emphasizes that in order to succeed in a global business environment, organizations must make investment in Human Resource Management (HRM) to allow them to acquire employees who possess better skills and capabilities than their competitors. This investment will be to their competitive advantage. Despite this recognition of the importance of employee development, the hospitality industry has historically been dominated by underdeveloped HR practices (Lucas, 2002).

Lucas also points out that 'the substance of HRM practices does not appear to be designed to foster constructive relations with employees or to represent a managerial approach that enables developing and drawing out the full potential of people, even though employees may be broadly satisfied with many aspects of their work' (Lucas, 2002). In addition, or maybe as a result, high employee turnover has been a recurring problem throughout the hospitality industry. Among the many cited reasons are low compensation, inadequate benefits, poor working conditions and compromised employee morale and attitudes (Maroudas et al., 2008).

Ng and Sorensen (2008) demonstrated that when managers provide recognition to employees, motivate employees to work together, and remove obstacles preventing effective performance, employees feel more obligated to stay with the company. This was succinctly summarized by Michel et al. (2013): '[P]roviding support to employees gives them the confidence to perform their jobs better and the motivation to stay with the organization.' Hospitality organizations can therefore enhance employee motivation and retention through the development and improvement of their working conditions. These conditions are inherently linked to the working environment.

While it seems likely that employees' reactions to their job characteristics could be affected by a predisposition to view their work environment negatively, no evidence exists to support this hypothesis (Spector et al., 2000). However, given the opportunity, many people will find something to complain about in relation to their workplace (Poulston, 2009). There is a strong link between the perceptions of employees and particular factors of their work environment that are separate from the work itself, including company policies, salary and vacations.

Such conditions are particularly troubling for the luxury hotel market, where high-quality service, requiring a sophisticated approach to HRM, is recognized as a critical source of competitive advantage (Maroudas et al., 2008). In a real sense, the services ofhotel employees represent their industry (Schneider and Bowen, 1993). This representation has commonly been limited to guest experiences. This suggests that there has been a dichotomy between the guest environment provided in luxury hotels and the working conditions of their employees.

It is therefore essential for hotel management to develop HRM practices that enable them to inspire and retain competent employees. This requires an understanding of what motivates employees at different levels of management and different stages of their careers (Enz and Siguaw, 2000). This implies that it is beneficial for hotel managers to understand what practices are most favorable to increase employee satisfaction and retention.

Herzberg (1966) proposes that people have two major types of needs, the first being extrinsic motivation factors relating to the context in which work is performed, rather than the work itself. These include working conditions and job security. When these factors are unfavorable, job dissatisfaction may result. Significantly, though, just fulfilling these needs does not result in satisfaction, but only in the reduction of dissatisfaction (Maroudas et al., 2008).

Employees also have intrinsic motivation needs or motivators, which include such factors as achievement and recognition. Unlike extrinsic factors, motivator factors may ideally result in job satisfaction (Maroudas et al., 2008). Herzberg's (1966) theory discusses the need for a 'balance' of these two types of needs.

The impact of fun as a motivating factor at work has also been explored. For example, Tews, Michel and Stafford (2013) conducted a study focusing on staff from a chain of themed restaurants in the United States. It was found that fun activities had a favorable impact on performance and manager support for fun had a favorable impact in reducing turnover.

Their findings support the view that fun may indeed have a beneficial effect, but the framing of that fun must be carefully aligned with both organizational goals and employee characteristics. 'Managers must learn how to achieve the delicate balance of allowing employees the freedom to enjoy themselves at work while simultaneously maintaining high levels of performance' (Tews et al., 2013).

Deery (2008) has recommended several actions that can be adopted at the organizational level to retain good staff as well as assist in balancing work and family life. Those particularly appropriate to the hospitality industry include allowing adequate breaks during the working day, staff functions that involve families, and providing health and well-being opportunities.

Các từ vựng nổi bật:

critical (adj): then chốt
superior (adj): tốt hơn
accomplish (adj): trọn vẹn
retain (v): giữ lại
by contrast: ngược lại
extend (v): kéo dài
emphasize (v): nhấn mạnh
investment (n): đầu tư
competitive (adj): cạnh tranh
recognition (n): sự công nhận
substance (n): cốt lõi
foster (v): thúc đẩy
constructive (adj): có tính xây dựng
managerial (adj): thuộc quản lý
potential (n): tiềm năng
turnover (n): nghỉ việc
compensation (n): lương
morale (n): tinh thần
obstacle (n): chướng ngại
succinctly (adv): súc tích
retention (n): sự duy trì
predisposition (n): khuynh hướng thiên về
separate (adj): riêng biệt
sophisticated (adj): phức tạp
dichotomy (n): sự lưỡng phân
extrinsic (adj): từ bên ngoài
intrinsic (adj): từ bên trong
align (v): sắp hàng
delicate (adj): tinh tế
simultaneously (adv): đồng thời
adequate (adj): đầy đủ
break (n): giờ giải lao

Các bạn cùng tham khảo nhé!

之前介紹過的凝血路徑也一樣，它在上世紀初至中期被提出，它可以很成功地解釋到PT與APTT等凝血檢查。但不能完全解釋到人體中發生的事，例如血友病患者明明有健全的extrinsic pathway，理應可以製造出纖維蛋白（fibrin）去凝血，為何仍會有嚴重流血問題？又例如凝血蛋白XII缺乏症患者理應會流血，為何他們的凝血功能完全正常？

為了解釋這些現象，科學家又提出了一個理應更接近人體中發生事情的凝血路徑模型，這個模型分4部分：

1. 起始（initiation）：血管破裂令到內皮細胞（endothelium）中的tissue factor外露，tissue factor激發凝血因子VII，VIIa再激發凝血因子X，Xa把凝血酶原（prothrombin）轉化成凝血酶（thrombin）。但這個過程只能製造很少的凝血酶，而且過程很短暫，凝血酶很快就會被tissue factor pathway inhibitor所移除。要製造更多凝血酶，就必須進一步加強凝血路徑。

2. 擴大（amplification）：凝血因子VIIa激活凝血因子IX，凝血酶激活凝血因子VIII及V。凝血因子IX及VIII一起激活凝血因子X，凝血因子V加速凝血因子X激活凝血酶原。凝血酶再進一步激活凝血因子VIII及V。這就形成了一個正反饋回路（positive feedback loop）。

3. 增長（propagation）：在正反饋回路的作用下，凝血路徑像雪球一樣越演越烈，最後製造出大量的纖維蛋白。

4. 穩固（stabilization）：纖維蛋白被凝血因子XIIIa（由凝血酶激活）連成纖維蛋白聚合物（polymer），令血栓變得穩固。

所以，請容小弟再提醒大家一次，上次跟大家的凝血路徑其實並不是真正在人體內發生的事。

科學的精神就是這樣，科學家先去觀察現象，然後提出假設去解釋現象，並且收集數據去支持假設，最後變成理論。但一個理論被提出以後，並不等如工作就完成了，如果某個理論未能完全解釋現象，科學家就會提出可以解釋更多現象的新理論，這些理論最終越來越接近現實。就如物理學中的原子模型，就由古希臘模型，演變到J J Thompson模型，再演變到Rutherford模型，再到Bohr模型，再到Schodinger模型。這些模型一個比一個接近現實，每一個都比前者解釋到更多的現象。